From c0cf6b412ecb099d49fe040d32fd5dd149f770d7 Mon Sep 17 00:00:00 2001 From: Bernhard Beschow Date: Wed, 11 Dec 2024 15:30:51 +0000 Subject: [PATCH 01/72] hw/net/lan9118: Extract lan9118_phy A very similar implementation of the same device exists in imx_fec. Prepare for a common implementation by extracting a device model into its own files. Some migration state has been moved into the new device model which breaks migration compatibility for the following machines: * smdkc210 * realview-* * vexpress-* * kzm * mps2-* While breaking migration ABI, fix the size of the MII registers to be 16 bit, as defined by IEEE 802.3u. Signed-off-by: Bernhard Beschow Tested-by: Guenter Roeck Reviewed-by: Peter Maydell Message-id: 20241102125724.532843-2-shentey@gmail.com Signed-off-by: Peter Maydell --- hw/net/Kconfig | 4 + hw/net/lan9118.c | 137 +++++----------------------- hw/net/lan9118_phy.c | 169 +++++++++++++++++++++++++++++++++++ hw/net/meson.build | 1 + include/hw/net/lan9118_phy.h | 37 ++++++++ 5 files changed, 233 insertions(+), 115 deletions(-) create mode 100644 hw/net/lan9118_phy.c create mode 100644 include/hw/net/lan9118_phy.h diff --git a/hw/net/Kconfig b/hw/net/Kconfig index 7fcc0d7faa..6b2ff2f937 100644 --- a/hw/net/Kconfig +++ b/hw/net/Kconfig @@ -62,8 +62,12 @@ config VMXNET3_PCI config SMC91C111 bool +config LAN9118_PHY + bool + config LAN9118 bool + select LAN9118_PHY select PTIMER config NE2000_ISA diff --git a/hw/net/lan9118.c b/hw/net/lan9118.c index db28a0ef30..99e87b7178 100644 --- a/hw/net/lan9118.c +++ b/hw/net/lan9118.c @@ -16,6 +16,7 @@ #include "net/net.h" #include "net/eth.h" #include "hw/irq.h" +#include "hw/net/lan9118_phy.h" #include "hw/net/lan9118.h" #include "hw/ptimer.h" #include "hw/qdev-properties.h" @@ -139,14 +140,6 @@ do { printf("lan9118: " fmt , ## __VA_ARGS__); } while (0) #define MAC_CR_RXEN 0x00000004 #define MAC_CR_RESERVED 0x7f404213 -#define PHY_INT_ENERGYON 0x80 -#define PHY_INT_AUTONEG_COMPLETE 0x40 -#define PHY_INT_FAULT 0x20 -#define PHY_INT_DOWN 0x10 -#define PHY_INT_AUTONEG_LP 0x08 -#define PHY_INT_PARFAULT 0x04 -#define PHY_INT_AUTONEG_PAGE 0x02 - #define GPT_TIMER_EN 0x20000000 /* @@ -228,11 +221,8 @@ struct lan9118_state { uint32_t mac_mii_data; uint32_t mac_flow; - uint32_t phy_status; - uint32_t phy_control; - uint32_t phy_advertise; - uint32_t phy_int; - uint32_t phy_int_mask; + Lan9118PhyState mii; + IRQState mii_irq; int32_t eeprom_writable; uint8_t eeprom[128]; @@ -274,8 +264,8 @@ struct lan9118_state { static const VMStateDescription vmstate_lan9118 = { .name = "lan9118", - .version_id = 2, - .minimum_version_id = 1, + .version_id = 3, + .minimum_version_id = 3, .fields = (const VMStateField[]) { VMSTATE_PTIMER(timer, lan9118_state), VMSTATE_UINT32(irq_cfg, lan9118_state), @@ -301,11 +291,6 @@ static const VMStateDescription vmstate_lan9118 = { VMSTATE_UINT32(mac_mii_acc, lan9118_state), VMSTATE_UINT32(mac_mii_data, lan9118_state), VMSTATE_UINT32(mac_flow, lan9118_state), - VMSTATE_UINT32(phy_status, lan9118_state), - VMSTATE_UINT32(phy_control, lan9118_state), - VMSTATE_UINT32(phy_advertise, lan9118_state), - VMSTATE_UINT32(phy_int, lan9118_state), - VMSTATE_UINT32(phy_int_mask, lan9118_state), VMSTATE_INT32(eeprom_writable, lan9118_state), VMSTATE_UINT8_ARRAY(eeprom, lan9118_state, 128), VMSTATE_INT32(tx_fifo_size, lan9118_state), @@ -385,9 +370,11 @@ static void lan9118_reload_eeprom(lan9118_state *s) lan9118_mac_changed(s); } -static void phy_update_irq(lan9118_state *s) +static void lan9118_update_irq(void *opaque, int n, int level) { - if (s->phy_int & s->phy_int_mask) { + lan9118_state *s = opaque; + + if (level) { s->int_sts |= PHY_INT; } else { s->int_sts &= ~PHY_INT; @@ -395,33 +382,10 @@ static void phy_update_irq(lan9118_state *s) lan9118_update(s); } -static void phy_update_link(lan9118_state *s) -{ - /* Autonegotiation status mirrors link status. */ - if (qemu_get_queue(s->nic)->link_down) { - s->phy_status &= ~0x0024; - s->phy_int |= PHY_INT_DOWN; - } else { - s->phy_status |= 0x0024; - s->phy_int |= PHY_INT_ENERGYON; - s->phy_int |= PHY_INT_AUTONEG_COMPLETE; - } - phy_update_irq(s); -} - static void lan9118_set_link(NetClientState *nc) { - phy_update_link(qemu_get_nic_opaque(nc)); -} - -static void phy_reset(lan9118_state *s) -{ - s->phy_status = 0x7809; - s->phy_control = 0x3000; - s->phy_advertise = 0x01e1; - s->phy_int_mask = 0; - s->phy_int = 0; - phy_update_link(s); + lan9118_phy_update_link(&LAN9118(qemu_get_nic_opaque(nc))->mii, + nc->link_down); } static void lan9118_reset(DeviceState *d) @@ -478,8 +442,6 @@ static void lan9118_reset(DeviceState *d) s->read_word_n = 0; s->write_word_n = 0; - phy_reset(s); - s->eeprom_writable = 0; lan9118_reload_eeprom(s); } @@ -678,7 +640,7 @@ static void do_tx_packet(lan9118_state *s) uint32_t status; /* FIXME: Honor TX disable, and allow queueing of packets. */ - if (s->phy_control & 0x4000) { + if (s->mii.control & 0x4000) { /* This assumes the receive routine doesn't touch the VLANClient. */ qemu_receive_packet(qemu_get_queue(s->nic), s->txp->data, s->txp->len); } else { @@ -834,68 +796,6 @@ static void tx_fifo_push(lan9118_state *s, uint32_t val) } } -static uint32_t do_phy_read(lan9118_state *s, int reg) -{ - uint32_t val; - - switch (reg) { - case 0: /* Basic Control */ - return s->phy_control; - case 1: /* Basic Status */ - return s->phy_status; - case 2: /* ID1 */ - return 0x0007; - case 3: /* ID2 */ - return 0xc0d1; - case 4: /* Auto-neg advertisement */ - return s->phy_advertise; - case 5: /* Auto-neg Link Partner Ability */ - return 0x0f71; - case 6: /* Auto-neg Expansion */ - return 1; - /* TODO 17, 18, 27, 29, 30, 31 */ - case 29: /* Interrupt source. */ - val = s->phy_int; - s->phy_int = 0; - phy_update_irq(s); - return val; - case 30: /* Interrupt mask */ - return s->phy_int_mask; - default: - qemu_log_mask(LOG_GUEST_ERROR, - "do_phy_read: PHY read reg %d\n", reg); - return 0; - } -} - -static void do_phy_write(lan9118_state *s, int reg, uint32_t val) -{ - switch (reg) { - case 0: /* Basic Control */ - if (val & 0x8000) { - phy_reset(s); - break; - } - s->phy_control = val & 0x7980; - /* Complete autonegotiation immediately. */ - if (val & 0x1000) { - s->phy_status |= 0x0020; - } - break; - case 4: /* Auto-neg advertisement */ - s->phy_advertise = (val & 0x2d7f) | 0x80; - break; - /* TODO 17, 18, 27, 31 */ - case 30: /* Interrupt mask */ - s->phy_int_mask = val & 0xff; - phy_update_irq(s); - break; - default: - qemu_log_mask(LOG_GUEST_ERROR, - "do_phy_write: PHY write reg %d = 0x%04x\n", reg, val); - } -} - static void do_mac_write(lan9118_state *s, int reg, uint32_t val) { switch (reg) { @@ -929,9 +829,9 @@ static void do_mac_write(lan9118_state *s, int reg, uint32_t val) if (val & 2) { DPRINTF("PHY write %d = 0x%04x\n", (val >> 6) & 0x1f, s->mac_mii_data); - do_phy_write(s, (val >> 6) & 0x1f, s->mac_mii_data); + lan9118_phy_write(&s->mii, (val >> 6) & 0x1f, s->mac_mii_data); } else { - s->mac_mii_data = do_phy_read(s, (val >> 6) & 0x1f); + s->mac_mii_data = lan9118_phy_read(&s->mii, (val >> 6) & 0x1f); DPRINTF("PHY read %d = 0x%04x\n", (val >> 6) & 0x1f, s->mac_mii_data); } @@ -1126,7 +1026,7 @@ static void lan9118_writel(void *opaque, hwaddr offset, break; case CSR_PMT_CTRL: if (val & 0x400) { - phy_reset(s); + lan9118_phy_reset(&s->mii); } s->pmt_ctrl &= ~0x34e; s->pmt_ctrl |= (val & 0x34e); @@ -1373,6 +1273,13 @@ static void lan9118_realize(DeviceState *dev, Error **errp) const MemoryRegionOps *mem_ops = s->mode_16bit ? &lan9118_16bit_mem_ops : &lan9118_mem_ops; + qemu_init_irq(&s->mii_irq, lan9118_update_irq, s, 0); + object_initialize_child(OBJECT(s), "mii", &s->mii, TYPE_LAN9118_PHY); + if (!sysbus_realize_and_unref(SYS_BUS_DEVICE(&s->mii), errp)) { + return; + } + qdev_connect_gpio_out(DEVICE(&s->mii), 0, &s->mii_irq); + memory_region_init_io(&s->mmio, OBJECT(dev), mem_ops, s, "lan9118-mmio", 0x100); sysbus_init_mmio(sbd, &s->mmio); diff --git a/hw/net/lan9118_phy.c b/hw/net/lan9118_phy.c new file mode 100644 index 0000000000..b22c3c2855 --- /dev/null +++ b/hw/net/lan9118_phy.c @@ -0,0 +1,169 @@ +/* + * SMSC LAN9118 PHY emulation + * + * Copyright (c) 2009 CodeSourcery, LLC. + * Written by Paul Brook + * + * This code is licensed under the GNU GPL v2 + * + * Contributions after 2012-01-13 are licensed under the terms of the + * GNU GPL, version 2 or (at your option) any later version. + */ + +#include "qemu/osdep.h" +#include "hw/net/lan9118_phy.h" +#include "hw/irq.h" +#include "hw/resettable.h" +#include "migration/vmstate.h" +#include "qemu/log.h" + +#define PHY_INT_ENERGYON (1 << 7) +#define PHY_INT_AUTONEG_COMPLETE (1 << 6) +#define PHY_INT_FAULT (1 << 5) +#define PHY_INT_DOWN (1 << 4) +#define PHY_INT_AUTONEG_LP (1 << 3) +#define PHY_INT_PARFAULT (1 << 2) +#define PHY_INT_AUTONEG_PAGE (1 << 1) + +static void lan9118_phy_update_irq(Lan9118PhyState *s) +{ + qemu_set_irq(s->irq, !!(s->ints & s->int_mask)); +} + +uint16_t lan9118_phy_read(Lan9118PhyState *s, int reg) +{ + uint16_t val; + + switch (reg) { + case 0: /* Basic Control */ + return s->control; + case 1: /* Basic Status */ + return s->status; + case 2: /* ID1 */ + return 0x0007; + case 3: /* ID2 */ + return 0xc0d1; + case 4: /* Auto-neg advertisement */ + return s->advertise; + case 5: /* Auto-neg Link Partner Ability */ + return 0x0f71; + case 6: /* Auto-neg Expansion */ + return 1; + /* TODO 17, 18, 27, 29, 30, 31 */ + case 29: /* Interrupt source. */ + val = s->ints; + s->ints = 0; + lan9118_phy_update_irq(s); + return val; + case 30: /* Interrupt mask */ + return s->int_mask; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "lan9118_phy_read: PHY read reg %d\n", reg); + return 0; + } +} + +void lan9118_phy_write(Lan9118PhyState *s, int reg, uint16_t val) +{ + switch (reg) { + case 0: /* Basic Control */ + if (val & 0x8000) { + lan9118_phy_reset(s); + break; + } + s->control = val & 0x7980; + /* Complete autonegotiation immediately. */ + if (val & 0x1000) { + s->status |= 0x0020; + } + break; + case 4: /* Auto-neg advertisement */ + s->advertise = (val & 0x2d7f) | 0x80; + break; + /* TODO 17, 18, 27, 31 */ + case 30: /* Interrupt mask */ + s->int_mask = val & 0xff; + lan9118_phy_update_irq(s); + break; + default: + qemu_log_mask(LOG_GUEST_ERROR, + "lan9118_phy_write: PHY write reg %d = 0x%04x\n", reg, val); + } +} + +void lan9118_phy_update_link(Lan9118PhyState *s, bool link_down) +{ + s->link_down = link_down; + + /* Autonegotiation status mirrors link status. */ + if (link_down) { + s->status &= ~0x0024; + s->ints |= PHY_INT_DOWN; + } else { + s->status |= 0x0024; + s->ints |= PHY_INT_ENERGYON; + s->ints |= PHY_INT_AUTONEG_COMPLETE; + } + lan9118_phy_update_irq(s); +} + +void lan9118_phy_reset(Lan9118PhyState *s) +{ + s->control = 0x3000; + s->status = 0x7809; + s->advertise = 0x01e1; + s->int_mask = 0; + s->ints = 0; + lan9118_phy_update_link(s, s->link_down); +} + +static void lan9118_phy_reset_hold(Object *obj, ResetType type) +{ + Lan9118PhyState *s = LAN9118_PHY(obj); + + lan9118_phy_reset(s); +} + +static void lan9118_phy_init(Object *obj) +{ + Lan9118PhyState *s = LAN9118_PHY(obj); + + qdev_init_gpio_out(DEVICE(s), &s->irq, 1); +} + +static const VMStateDescription vmstate_lan9118_phy = { + .name = "lan9118-phy", + .version_id = 1, + .minimum_version_id = 1, + .fields = (const VMStateField[]) { + VMSTATE_UINT16(control, Lan9118PhyState), + VMSTATE_UINT16(status, Lan9118PhyState), + VMSTATE_UINT16(advertise, Lan9118PhyState), + VMSTATE_UINT16(ints, Lan9118PhyState), + VMSTATE_UINT16(int_mask, Lan9118PhyState), + VMSTATE_BOOL(link_down, Lan9118PhyState), + VMSTATE_END_OF_LIST() + } +}; + +static void lan9118_phy_class_init(ObjectClass *klass, void *data) +{ + ResettableClass *rc = RESETTABLE_CLASS(klass); + DeviceClass *dc = DEVICE_CLASS(klass); + + rc->phases.hold = lan9118_phy_reset_hold; + dc->vmsd = &vmstate_lan9118_phy; +} + +static const TypeInfo types[] = { + { + .name = TYPE_LAN9118_PHY, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(Lan9118PhyState), + .instance_init = lan9118_phy_init, + .class_init = lan9118_phy_class_init, + } +}; + +DEFINE_TYPES(types) diff --git a/hw/net/meson.build b/hw/net/meson.build index 00a9e9dd51..3bb5d749a8 100644 --- a/hw/net/meson.build +++ b/hw/net/meson.build @@ -19,6 +19,7 @@ system_ss.add(when: 'CONFIG_VMXNET3_PCI', if_true: files('vmxnet3.c')) system_ss.add(when: 'CONFIG_SMC91C111', if_true: files('smc91c111.c')) system_ss.add(when: 'CONFIG_LAN9118', if_true: files('lan9118.c')) +system_ss.add(when: 'CONFIG_LAN9118_PHY', if_true: files('lan9118_phy.c')) system_ss.add(when: 'CONFIG_NE2000_ISA', if_true: files('ne2000-isa.c')) system_ss.add(when: 'CONFIG_OPENCORES_ETH', if_true: files('opencores_eth.c')) system_ss.add(when: 'CONFIG_XGMAC', if_true: files('xgmac.c')) diff --git a/include/hw/net/lan9118_phy.h b/include/hw/net/lan9118_phy.h new file mode 100644 index 0000000000..af12fc33d5 --- /dev/null +++ b/include/hw/net/lan9118_phy.h @@ -0,0 +1,37 @@ +/* + * SMSC LAN9118 PHY emulation + * + * Copyright (c) 2009 CodeSourcery, LLC. + * Written by Paul Brook + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef HW_NET_LAN9118_PHY_H +#define HW_NET_LAN9118_PHY_H + +#include "qom/object.h" +#include "hw/sysbus.h" + +#define TYPE_LAN9118_PHY "lan9118-phy" +OBJECT_DECLARE_SIMPLE_TYPE(Lan9118PhyState, LAN9118_PHY) + +typedef struct Lan9118PhyState { + SysBusDevice parent_obj; + + uint16_t status; + uint16_t control; + uint16_t advertise; + uint16_t ints; + uint16_t int_mask; + qemu_irq irq; + bool link_down; +} Lan9118PhyState; + +void lan9118_phy_update_link(Lan9118PhyState *s, bool link_down); +void lan9118_phy_reset(Lan9118PhyState *s); +uint16_t lan9118_phy_read(Lan9118PhyState *s, int reg); +void lan9118_phy_write(Lan9118PhyState *s, int reg, uint16_t val); + +#endif From c01194e17a01b2a17805dfa0c710aad7c05eab69 Mon Sep 17 00:00:00 2001 From: Bernhard Beschow Date: Wed, 11 Dec 2024 15:30:51 +0000 Subject: [PATCH 02/72] hw/net/lan9118_phy: Reuse in imx_fec and consolidate implementations imx_fec models the same PHY as lan9118_phy. The code is almost the same with imx_fec having more logging and tracing. Merge these improvements into lan9118_phy and reuse in imx_fec to fix the code duplication. Some migration state how resides in the new device model which breaks migration compatibility for the following machines: * imx25-pdk * sabrelite * mcimx7d-sabre * mcimx6ul-evk Signed-off-by: Bernhard Beschow Tested-by: Guenter Roeck Reviewed-by: Peter Maydell Message-id: 20241102125724.532843-3-shentey@gmail.com Signed-off-by: Peter Maydell --- hw/net/Kconfig | 1 + hw/net/imx_fec.c | 146 ++++----------------------------------- hw/net/lan9118_phy.c | 82 ++++++++++++++++------ hw/net/trace-events | 10 +-- include/hw/net/imx_fec.h | 9 ++- 5 files changed, 85 insertions(+), 163 deletions(-) diff --git a/hw/net/Kconfig b/hw/net/Kconfig index 6b2ff2f937..7f80218d10 100644 --- a/hw/net/Kconfig +++ b/hw/net/Kconfig @@ -93,6 +93,7 @@ config ALLWINNER_SUN8I_EMAC config IMX_FEC bool + select LAN9118_PHY config CADENCE bool diff --git a/hw/net/imx_fec.c b/hw/net/imx_fec.c index 6294d29202..4ee6f74206 100644 --- a/hw/net/imx_fec.c +++ b/hw/net/imx_fec.c @@ -203,17 +203,12 @@ static const VMStateDescription vmstate_imx_eth_txdescs = { static const VMStateDescription vmstate_imx_eth = { .name = TYPE_IMX_FEC, - .version_id = 2, - .minimum_version_id = 2, + .version_id = 3, + .minimum_version_id = 3, .fields = (const VMStateField[]) { VMSTATE_UINT32_ARRAY(regs, IMXFECState, ENET_MAX), VMSTATE_UINT32(rx_descriptor, IMXFECState), VMSTATE_UINT32(tx_descriptor[0], IMXFECState), - VMSTATE_UINT32(phy_status, IMXFECState), - VMSTATE_UINT32(phy_control, IMXFECState), - VMSTATE_UINT32(phy_advertise, IMXFECState), - VMSTATE_UINT32(phy_int, IMXFECState), - VMSTATE_UINT32(phy_int_mask, IMXFECState), VMSTATE_END_OF_LIST() }, .subsections = (const VMStateDescription * const []) { @@ -222,14 +217,6 @@ static const VMStateDescription vmstate_imx_eth = { }, }; -#define PHY_INT_ENERGYON (1 << 7) -#define PHY_INT_AUTONEG_COMPLETE (1 << 6) -#define PHY_INT_FAULT (1 << 5) -#define PHY_INT_DOWN (1 << 4) -#define PHY_INT_AUTONEG_LP (1 << 3) -#define PHY_INT_PARFAULT (1 << 2) -#define PHY_INT_AUTONEG_PAGE (1 << 1) - static void imx_eth_update(IMXFECState *s); /* @@ -238,47 +225,19 @@ static void imx_eth_update(IMXFECState *s); * For now we don't handle any GPIO/interrupt line, so the OS will * have to poll for the PHY status. */ -static void imx_phy_update_irq(IMXFECState *s) +static void imx_phy_update_irq(void *opaque, int n, int level) { - imx_eth_update(s); -} - -static void imx_phy_update_link(IMXFECState *s) -{ - /* Autonegotiation status mirrors link status. */ - if (qemu_get_queue(s->nic)->link_down) { - trace_imx_phy_update_link("down"); - s->phy_status &= ~0x0024; - s->phy_int |= PHY_INT_DOWN; - } else { - trace_imx_phy_update_link("up"); - s->phy_status |= 0x0024; - s->phy_int |= PHY_INT_ENERGYON; - s->phy_int |= PHY_INT_AUTONEG_COMPLETE; - } - imx_phy_update_irq(s); + imx_eth_update(opaque); } static void imx_eth_set_link(NetClientState *nc) { - imx_phy_update_link(IMX_FEC(qemu_get_nic_opaque(nc))); -} - -static void imx_phy_reset(IMXFECState *s) -{ - trace_imx_phy_reset(); - - s->phy_status = 0x7809; - s->phy_control = 0x3000; - s->phy_advertise = 0x01e1; - s->phy_int_mask = 0; - s->phy_int = 0; - imx_phy_update_link(s); + lan9118_phy_update_link(&IMX_FEC(qemu_get_nic_opaque(nc))->mii, + nc->link_down); } static uint32_t imx_phy_read(IMXFECState *s, int reg) { - uint32_t val; uint32_t phy = reg / 32; if (!s->phy_connected) { @@ -296,54 +255,7 @@ static uint32_t imx_phy_read(IMXFECState *s, int reg) reg %= 32; - switch (reg) { - case 0: /* Basic Control */ - val = s->phy_control; - break; - case 1: /* Basic Status */ - val = s->phy_status; - break; - case 2: /* ID1 */ - val = 0x0007; - break; - case 3: /* ID2 */ - val = 0xc0d1; - break; - case 4: /* Auto-neg advertisement */ - val = s->phy_advertise; - break; - case 5: /* Auto-neg Link Partner Ability */ - val = 0x0f71; - break; - case 6: /* Auto-neg Expansion */ - val = 1; - break; - case 29: /* Interrupt source. */ - val = s->phy_int; - s->phy_int = 0; - imx_phy_update_irq(s); - break; - case 30: /* Interrupt mask */ - val = s->phy_int_mask; - break; - case 17: - case 18: - case 27: - case 31: - qemu_log_mask(LOG_UNIMP, "[%s.phy]%s: reg %d not implemented\n", - TYPE_IMX_FEC, __func__, reg); - val = 0; - break; - default: - qemu_log_mask(LOG_GUEST_ERROR, "[%s.phy]%s: Bad address at offset %d\n", - TYPE_IMX_FEC, __func__, reg); - val = 0; - break; - } - - trace_imx_phy_read(val, phy, reg); - - return val; + return lan9118_phy_read(&s->mii, reg); } static void imx_phy_write(IMXFECState *s, int reg, uint32_t val) @@ -365,39 +277,7 @@ static void imx_phy_write(IMXFECState *s, int reg, uint32_t val) reg %= 32; - trace_imx_phy_write(val, phy, reg); - - switch (reg) { - case 0: /* Basic Control */ - if (val & 0x8000) { - imx_phy_reset(s); - } else { - s->phy_control = val & 0x7980; - /* Complete autonegotiation immediately. */ - if (val & 0x1000) { - s->phy_status |= 0x0020; - } - } - break; - case 4: /* Auto-neg advertisement */ - s->phy_advertise = (val & 0x2d7f) | 0x80; - break; - case 30: /* Interrupt mask */ - s->phy_int_mask = val & 0xff; - imx_phy_update_irq(s); - break; - case 17: - case 18: - case 27: - case 31: - qemu_log_mask(LOG_UNIMP, "[%s.phy)%s: reg %d not implemented\n", - TYPE_IMX_FEC, __func__, reg); - break; - default: - qemu_log_mask(LOG_GUEST_ERROR, "[%s.phy]%s: Bad address at offset %d\n", - TYPE_IMX_FEC, __func__, reg); - break; - } + lan9118_phy_write(&s->mii, reg, val); } static void imx_fec_read_bd(IMXFECBufDesc *bd, dma_addr_t addr) @@ -682,9 +562,6 @@ static void imx_eth_reset(DeviceState *d) s->rx_descriptor = 0; memset(s->tx_descriptor, 0, sizeof(s->tx_descriptor)); - - /* We also reset the PHY */ - imx_phy_reset(s); } static uint32_t imx_default_read(IMXFECState *s, uint32_t index) @@ -1329,6 +1206,13 @@ static void imx_eth_realize(DeviceState *dev, Error **errp) sysbus_init_irq(sbd, &s->irq[0]); sysbus_init_irq(sbd, &s->irq[1]); + qemu_init_irq(&s->mii_irq, imx_phy_update_irq, s, 0); + object_initialize_child(OBJECT(s), "mii", &s->mii, TYPE_LAN9118_PHY); + if (!sysbus_realize_and_unref(SYS_BUS_DEVICE(&s->mii), errp)) { + return; + } + qdev_connect_gpio_out(DEVICE(&s->mii), 0, &s->mii_irq); + qemu_macaddr_default_if_unset(&s->conf.macaddr); s->nic = qemu_new_nic(&imx_eth_net_info, &s->conf, diff --git a/hw/net/lan9118_phy.c b/hw/net/lan9118_phy.c index b22c3c2855..d2dcd732ac 100644 --- a/hw/net/lan9118_phy.c +++ b/hw/net/lan9118_phy.c @@ -4,6 +4,8 @@ * Copyright (c) 2009 CodeSourcery, LLC. * Written by Paul Brook * + * Copyright (c) 2013 Jean-Christophe Dubois. + * * This code is licensed under the GNU GPL v2 * * Contributions after 2012-01-13 are licensed under the terms of the @@ -16,6 +18,7 @@ #include "hw/resettable.h" #include "migration/vmstate.h" #include "qemu/log.h" +#include "trace.h" #define PHY_INT_ENERGYON (1 << 7) #define PHY_INT_AUTONEG_COMPLETE (1 << 6) @@ -36,59 +39,88 @@ uint16_t lan9118_phy_read(Lan9118PhyState *s, int reg) switch (reg) { case 0: /* Basic Control */ - return s->control; + val = s->control; + break; case 1: /* Basic Status */ - return s->status; + val = s->status; + break; case 2: /* ID1 */ - return 0x0007; + val = 0x0007; + break; case 3: /* ID2 */ - return 0xc0d1; + val = 0xc0d1; + break; case 4: /* Auto-neg advertisement */ - return s->advertise; + val = s->advertise; + break; case 5: /* Auto-neg Link Partner Ability */ - return 0x0f71; + val = 0x0f71; + break; case 6: /* Auto-neg Expansion */ - return 1; - /* TODO 17, 18, 27, 29, 30, 31 */ + val = 1; + break; case 29: /* Interrupt source. */ val = s->ints; s->ints = 0; lan9118_phy_update_irq(s); - return val; + break; case 30: /* Interrupt mask */ - return s->int_mask; + val = s->int_mask; + break; + case 17: + case 18: + case 27: + case 31: + qemu_log_mask(LOG_UNIMP, "%s: reg %d not implemented\n", + __func__, reg); + val = 0; + break; default: - qemu_log_mask(LOG_GUEST_ERROR, - "lan9118_phy_read: PHY read reg %d\n", reg); - return 0; + qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad address at offset %d\n", + __func__, reg); + val = 0; + break; } + + trace_lan9118_phy_read(val, reg); + + return val; } void lan9118_phy_write(Lan9118PhyState *s, int reg, uint16_t val) { + trace_lan9118_phy_write(val, reg); + switch (reg) { case 0: /* Basic Control */ if (val & 0x8000) { lan9118_phy_reset(s); - break; - } - s->control = val & 0x7980; - /* Complete autonegotiation immediately. */ - if (val & 0x1000) { - s->status |= 0x0020; + } else { + s->control = val & 0x7980; + /* Complete autonegotiation immediately. */ + if (val & 0x1000) { + s->status |= 0x0020; + } } break; case 4: /* Auto-neg advertisement */ s->advertise = (val & 0x2d7f) | 0x80; break; - /* TODO 17, 18, 27, 31 */ case 30: /* Interrupt mask */ s->int_mask = val & 0xff; lan9118_phy_update_irq(s); break; + case 17: + case 18: + case 27: + case 31: + qemu_log_mask(LOG_UNIMP, "%s: reg %d not implemented\n", + __func__, reg); + break; default: - qemu_log_mask(LOG_GUEST_ERROR, - "lan9118_phy_write: PHY write reg %d = 0x%04x\n", reg, val); + qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad address at offset %d\n", + __func__, reg); + break; } } @@ -98,9 +130,11 @@ void lan9118_phy_update_link(Lan9118PhyState *s, bool link_down) /* Autonegotiation status mirrors link status. */ if (link_down) { + trace_lan9118_phy_update_link("down"); s->status &= ~0x0024; s->ints |= PHY_INT_DOWN; } else { + trace_lan9118_phy_update_link("up"); s->status |= 0x0024; s->ints |= PHY_INT_ENERGYON; s->ints |= PHY_INT_AUTONEG_COMPLETE; @@ -110,6 +144,8 @@ void lan9118_phy_update_link(Lan9118PhyState *s, bool link_down) void lan9118_phy_reset(Lan9118PhyState *s) { + trace_lan9118_phy_reset(); + s->control = 0x3000; s->status = 0x7809; s->advertise = 0x01e1; @@ -137,8 +173,8 @@ static const VMStateDescription vmstate_lan9118_phy = { .version_id = 1, .minimum_version_id = 1, .fields = (const VMStateField[]) { - VMSTATE_UINT16(control, Lan9118PhyState), VMSTATE_UINT16(status, Lan9118PhyState), + VMSTATE_UINT16(control, Lan9118PhyState), VMSTATE_UINT16(advertise, Lan9118PhyState), VMSTATE_UINT16(ints, Lan9118PhyState), VMSTATE_UINT16(int_mask, Lan9118PhyState), diff --git a/hw/net/trace-events b/hw/net/trace-events index d0f1d8c0fb..6100ec324a 100644 --- a/hw/net/trace-events +++ b/hw/net/trace-events @@ -10,6 +10,12 @@ allwinner_sun8i_emac_set_link(bool active) "Set link: active=%u" allwinner_sun8i_emac_read(uint64_t offset, uint64_t val) "MMIO read: offset=0x%" PRIx64 " value=0x%" PRIx64 allwinner_sun8i_emac_write(uint64_t offset, uint64_t val) "MMIO write: offset=0x%" PRIx64 " value=0x%" PRIx64 +# lan9118_phy.c +lan9118_phy_read(uint16_t val, int reg) "[0x%02x] -> 0x%04" PRIx16 +lan9118_phy_write(uint16_t val, int reg) "[0x%02x] <- 0x%04" PRIx16 +lan9118_phy_update_link(const char *s) "%s" +lan9118_phy_reset(void) "" + # lance.c lance_mem_readw(uint64_t addr, uint32_t ret) "addr=0x%"PRIx64"val=0x%04x" lance_mem_writew(uint64_t addr, uint32_t val) "addr=0x%"PRIx64"val=0x%04x" @@ -428,12 +434,8 @@ i82596_set_multicast(uint16_t count) "Added %d multicast entries" i82596_channel_attention(void *s) "%p: Received CHANNEL ATTENTION" # imx_fec.c -imx_phy_read(uint32_t val, int phy, int reg) "0x%04"PRIx32" <= phy[%d].reg[%d]" imx_phy_read_num(int phy, int configured) "read request from unconfigured phy %d (configured %d)" -imx_phy_write(uint32_t val, int phy, int reg) "0x%04"PRIx32" => phy[%d].reg[%d]" imx_phy_write_num(int phy, int configured) "write request to unconfigured phy %d (configured %d)" -imx_phy_update_link(const char *s) "%s" -imx_phy_reset(void) "" imx_fec_read_bd(uint64_t addr, int flags, int len, int data) "tx_bd 0x%"PRIx64" flags 0x%04x len %d data 0x%08x" imx_enet_read_bd(uint64_t addr, int flags, int len, int data, int options, int status) "tx_bd 0x%"PRIx64" flags 0x%04x len %d data 0x%08x option 0x%04x status 0x%04x" imx_eth_tx_bd_busy(void) "tx_bd ran out of descriptors to transmit" diff --git a/include/hw/net/imx_fec.h b/include/hw/net/imx_fec.h index 2d13290c78..83b21637ee 100644 --- a/include/hw/net/imx_fec.h +++ b/include/hw/net/imx_fec.h @@ -31,6 +31,8 @@ OBJECT_DECLARE_SIMPLE_TYPE(IMXFECState, IMX_FEC) #define TYPE_IMX_ENET "imx.enet" #include "hw/sysbus.h" +#include "hw/net/lan9118_phy.h" +#include "hw/irq.h" #include "net/net.h" #define ENET_EIR 1 @@ -264,11 +266,8 @@ struct IMXFECState { uint32_t tx_descriptor[ENET_TX_RING_NUM]; uint32_t tx_ring_num; - uint32_t phy_status; - uint32_t phy_control; - uint32_t phy_advertise; - uint32_t phy_int; - uint32_t phy_int_mask; + Lan9118PhyState mii; + IRQState mii_irq; uint32_t phy_num; bool phy_connected; struct IMXFECState *phy_consumer; From bbaaee8cc665bbfea1a77f7940b5bb7e02d2a7ef Mon Sep 17 00:00:00 2001 From: Bernhard Beschow Date: Wed, 11 Dec 2024 15:30:52 +0000 Subject: [PATCH 03/72] hw/net/lan9118_phy: Fix off-by-one error in MII_ANLPAR register Turns 0x70 into 0xe0 (== 0x70 << 1) which adds the missing MII_ANLPAR_TX and fixes the MSB of selector field to be zero, as specified in the datasheet. Fixes: 2a424990170b "LAN9118 emulation" Signed-off-by: Bernhard Beschow Tested-by: Guenter Roeck Reviewed-by: Peter Maydell Message-id: 20241102125724.532843-4-shentey@gmail.com Signed-off-by: Peter Maydell --- hw/net/lan9118_phy.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/hw/net/lan9118_phy.c b/hw/net/lan9118_phy.c index d2dcd732ac..d8fc9ddd3a 100644 --- a/hw/net/lan9118_phy.c +++ b/hw/net/lan9118_phy.c @@ -54,7 +54,7 @@ uint16_t lan9118_phy_read(Lan9118PhyState *s, int reg) val = s->advertise; break; case 5: /* Auto-neg Link Partner Ability */ - val = 0x0f71; + val = 0x0fe1; break; case 6: /* Auto-neg Expansion */ val = 1; From 212a52c8f2e4ce13251ed998db57af22b34e7e6f Mon Sep 17 00:00:00 2001 From: Bernhard Beschow Date: Wed, 11 Dec 2024 15:30:52 +0000 Subject: [PATCH 04/72] hw/net/lan9118_phy: Reuse MII constants Prefer named constants over magic values for better readability. Reviewed-by: Peter Maydell Signed-off-by: Bernhard Beschow Tested-by: Guenter Roeck Message-id: 20241102125724.532843-5-shentey@gmail.com Signed-off-by: Peter Maydell --- hw/net/lan9118_phy.c | 63 ++++++++++++++++++++++++++++---------------- include/hw/net/mii.h | 6 +++++ 2 files changed, 46 insertions(+), 23 deletions(-) diff --git a/hw/net/lan9118_phy.c b/hw/net/lan9118_phy.c index d8fc9ddd3a..874dae4155 100644 --- a/hw/net/lan9118_phy.c +++ b/hw/net/lan9118_phy.c @@ -14,6 +14,7 @@ #include "qemu/osdep.h" #include "hw/net/lan9118_phy.h" +#include "hw/net/mii.h" #include "hw/irq.h" #include "hw/resettable.h" #include "migration/vmstate.h" @@ -38,26 +39,28 @@ uint16_t lan9118_phy_read(Lan9118PhyState *s, int reg) uint16_t val; switch (reg) { - case 0: /* Basic Control */ + case MII_BMCR: val = s->control; break; - case 1: /* Basic Status */ + case MII_BMSR: val = s->status; break; - case 2: /* ID1 */ - val = 0x0007; + case MII_PHYID1: + val = SMSCLAN9118_PHYID1; break; - case 3: /* ID2 */ - val = 0xc0d1; + case MII_PHYID2: + val = SMSCLAN9118_PHYID2; break; - case 4: /* Auto-neg advertisement */ + case MII_ANAR: val = s->advertise; break; - case 5: /* Auto-neg Link Partner Ability */ - val = 0x0fe1; + case MII_ANLPAR: + val = MII_ANLPAR_PAUSEASY | MII_ANLPAR_PAUSE | MII_ANLPAR_T4 | + MII_ANLPAR_TXFD | MII_ANLPAR_TX | MII_ANLPAR_10FD | + MII_ANLPAR_10 | MII_ANLPAR_CSMACD; break; - case 6: /* Auto-neg Expansion */ - val = 1; + case MII_ANER: + val = MII_ANER_NWAY; break; case 29: /* Interrupt source. */ val = s->ints; @@ -92,19 +95,24 @@ void lan9118_phy_write(Lan9118PhyState *s, int reg, uint16_t val) trace_lan9118_phy_write(val, reg); switch (reg) { - case 0: /* Basic Control */ - if (val & 0x8000) { + case MII_BMCR: + if (val & MII_BMCR_RESET) { lan9118_phy_reset(s); } else { - s->control = val & 0x7980; + s->control = val & (MII_BMCR_LOOPBACK | MII_BMCR_SPEED100 | + MII_BMCR_AUTOEN | MII_BMCR_PDOWN | MII_BMCR_FD | + MII_BMCR_CTST); /* Complete autonegotiation immediately. */ - if (val & 0x1000) { - s->status |= 0x0020; + if (val & MII_BMCR_AUTOEN) { + s->status |= MII_BMSR_AN_COMP; } } break; - case 4: /* Auto-neg advertisement */ - s->advertise = (val & 0x2d7f) | 0x80; + case MII_ANAR: + s->advertise = (val & (MII_ANAR_RFAULT | MII_ANAR_PAUSE_ASYM | + MII_ANAR_PAUSE | MII_ANAR_10FD | MII_ANAR_10 | + MII_ANAR_SELECT)) + | MII_ANAR_TX; break; case 30: /* Interrupt mask */ s->int_mask = val & 0xff; @@ -131,11 +139,11 @@ void lan9118_phy_update_link(Lan9118PhyState *s, bool link_down) /* Autonegotiation status mirrors link status. */ if (link_down) { trace_lan9118_phy_update_link("down"); - s->status &= ~0x0024; + s->status &= ~(MII_BMSR_AN_COMP | MII_BMSR_LINK_ST); s->ints |= PHY_INT_DOWN; } else { trace_lan9118_phy_update_link("up"); - s->status |= 0x0024; + s->status |= MII_BMSR_AN_COMP | MII_BMSR_LINK_ST; s->ints |= PHY_INT_ENERGYON; s->ints |= PHY_INT_AUTONEG_COMPLETE; } @@ -146,9 +154,18 @@ void lan9118_phy_reset(Lan9118PhyState *s) { trace_lan9118_phy_reset(); - s->control = 0x3000; - s->status = 0x7809; - s->advertise = 0x01e1; + s->control = MII_BMCR_AUTOEN | MII_BMCR_SPEED100; + s->status = MII_BMSR_100TX_FD + | MII_BMSR_100TX_HD + | MII_BMSR_10T_FD + | MII_BMSR_10T_HD + | MII_BMSR_AUTONEG + | MII_BMSR_EXTCAP; + s->advertise = MII_ANAR_TXFD + | MII_ANAR_TX + | MII_ANAR_10FD + | MII_ANAR_10 + | MII_ANAR_CSMACD; s->int_mask = 0; s->ints = 0; lan9118_phy_update_link(s, s->link_down); diff --git a/include/hw/net/mii.h b/include/hw/net/mii.h index f7feddac9b..55bf7c92a1 100644 --- a/include/hw/net/mii.h +++ b/include/hw/net/mii.h @@ -71,6 +71,7 @@ #define MII_BMSR_JABBER (1 << 1) /* Jabber detected */ #define MII_BMSR_EXTCAP (1 << 0) /* Ext-reg capability */ +#define MII_ANAR_RFAULT (1 << 13) /* Say we can detect faults */ #define MII_ANAR_PAUSE_ASYM (1 << 11) /* Try for asymmetric pause */ #define MII_ANAR_PAUSE (1 << 10) /* Try for pause */ #define MII_ANAR_TXFD (1 << 8) @@ -78,6 +79,7 @@ #define MII_ANAR_10FD (1 << 6) #define MII_ANAR_10 (1 << 5) #define MII_ANAR_CSMACD (1 << 0) +#define MII_ANAR_SELECT (0x001f) /* Selector bits */ #define MII_ANLPAR_ACK (1 << 14) #define MII_ANLPAR_PAUSEASY (1 << 11) /* can pause asymmetrically */ @@ -112,6 +114,10 @@ #define RTL8201CP_PHYID1 0x0000 #define RTL8201CP_PHYID2 0x8201 +/* SMSC LAN9118 */ +#define SMSCLAN9118_PHYID1 0x0007 +#define SMSCLAN9118_PHYID2 0xc0d1 + /* RealTek 8211E */ #define RTL8211E_PHYID1 0x001c #define RTL8211E_PHYID2 0xc915 From 973a2fac48590d9b4e6f1601a13c7f96a1fd5deb Mon Sep 17 00:00:00 2001 From: Bernhard Beschow Date: Wed, 11 Dec 2024 15:30:52 +0000 Subject: [PATCH 05/72] hw/net/lan9118_phy: Add missing 100 mbps full duplex advertisement The real device advertises this mode and the device model already advertises 100 mbps half duplex and 10 mbps full+half duplex. So advertise this mode to make the model more realistic. Reviewed-by: Peter Maydell Signed-off-by: Bernhard Beschow Tested-by: Guenter Roeck Message-id: 20241102125724.532843-6-shentey@gmail.com Signed-off-by: Peter Maydell --- hw/net/lan9118_phy.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/hw/net/lan9118_phy.c b/hw/net/lan9118_phy.c index 874dae4155..5c53a4a1e3 100644 --- a/hw/net/lan9118_phy.c +++ b/hw/net/lan9118_phy.c @@ -110,8 +110,8 @@ void lan9118_phy_write(Lan9118PhyState *s, int reg, uint16_t val) break; case MII_ANAR: s->advertise = (val & (MII_ANAR_RFAULT | MII_ANAR_PAUSE_ASYM | - MII_ANAR_PAUSE | MII_ANAR_10FD | MII_ANAR_10 | - MII_ANAR_SELECT)) + MII_ANAR_PAUSE | MII_ANAR_TXFD | MII_ANAR_10FD | + MII_ANAR_10 | MII_ANAR_SELECT)) | MII_ANAR_TX; break; case 30: /* Interrupt mask */ From 8adcff4ae760a960c8b44c9d3da0428322e3f677 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:52 +0000 Subject: [PATCH 06/72] fpu: handle raising Invalid for infzero in pick_nan_muladd For IEEE fused multiply-add, the (0 * inf) + NaN case should raise Invalid for the multiplication of 0 by infinity. Currently we handle this in the per-architecture ifdef ladder in pickNaNMulAdd(). However, since this isn't really architecture specific we can hoist it up to the generic code. For the cases where the infzero test in pickNaNMulAdd was returning 2, we can delete the check entirely and allow the code to fall into the normal pick-a-NaN handling, because this will return 2 anyway (input 'c' being the only NaN in this case). For the cases where infzero was returning 3 to indicate "return the default NaN", we must retain that "return 3". For Arm, this looks like it might be a behaviour change because we used to set float_flag_invalid | float_flag_invalid_imz only if C is a quiet NaN. However, it is not, because Arm target code never looks at float_flag_invalid_imz, and for the (0 * inf) + SNaN case we already raised float_flag_invalid via the "abc_mask & float_cmask_snan" check in pick_nan_muladd. For any target architecture using the "default implementation" at the bottom of the ifdef, this is a behaviour change but will be fixing a bug (where we failed to raise the Invalid exception for (0 * inf + QNaN). The architectures using the default case are: * hppa * i386 * sh4 * tricore The x86, Tricore and SH4 CPU architecture manuals are clear that this should have raised Invalid; HPPA is a bit vaguer but still seems clear enough. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-2-peter.maydell@linaro.org --- fpu/softfloat-parts.c.inc | 13 +++++++------ fpu/softfloat-specialize.c.inc | 29 +---------------------------- 2 files changed, 8 insertions(+), 34 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index cc6e06b976..d63cd957a1 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -66,19 +66,20 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, int ab_mask, int abc_mask) { int which; + bool infzero = (ab_mask == float_cmask_infzero); if (unlikely(abc_mask & float_cmask_snan)) { float_raise(float_flag_invalid | float_flag_invalid_snan, s); } - which = pickNaNMulAdd(a->cls, b->cls, c->cls, - ab_mask == float_cmask_infzero, s); + if (infzero) { + /* This is (0 * inf) + NaN or (inf * 0) + NaN */ + float_raise(float_flag_invalid | float_flag_invalid_imz, s); + } + + which = pickNaNMulAdd(a->cls, b->cls, c->cls, infzero, s); if (s->default_nan_mode || which == 3) { - /* - * Note that this check is after pickNaNMulAdd so that function - * has an opportunity to set the Invalid flag for infzero. - */ parts_default_nan(a, s); return a; } diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 9bca03c4ae..c557c41b2a 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -480,7 +480,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * the default NaN */ if (infzero && is_qnan(c_cls)) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); return 3; } @@ -507,7 +506,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * case sets InvalidOp and returns the default NaN */ if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); return 3; } /* Prefer sNaN over qNaN, in the a, b, c order. */ @@ -529,10 +527,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * For MIPS systems that conform to IEEE754-2008, the (inf,zero,nan) * case sets InvalidOp and returns the input value 'c' */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } /* Prefer sNaN over qNaN, in the c, a, b order. */ if (is_snan(c_cls)) { return 2; @@ -553,10 +547,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) * case sets InvalidOp and returns the input value 'c' */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } + /* Prefer sNaN over qNaN, in the c, a, b order. */ if (is_snan(c_cls)) { return 2; @@ -576,10 +567,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * to return an input NaN if we have one (ie c) rather than generating * a default NaN */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } /* If fRA is a NaN return it; otherwise if fRB is a NaN return it; * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB @@ -592,14 +579,9 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, return 1; } #elif defined(TARGET_RISCV) - /* For RISC-V, InvalidOp is set when multiplicands are Inf and zero */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - } return 3; /* default NaN */ #elif defined(TARGET_S390X) if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); return 3; } @@ -617,11 +599,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, return 2; } #elif defined(TARGET_SPARC) - /* For (inf,0,nan) return c. */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } /* Prefer SNaN over QNaN, order C, B, A. */ if (is_snan(c_cls)) { return 2; @@ -641,10 +618,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * For Xtensa, the (inf,zero,nan) case sets InvalidOp and returns * an input NaN if we have one (ie c). */ - if (infzero) { - float_raise(float_flag_invalid | float_flag_invalid_imz, status); - return 2; - } if (status->use_first_nan) { if (is_nan(a_cls)) { return 0; From ed885e306900e54a618ac9cc11ab68683db472b1 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:53 +0000 Subject: [PATCH 07/72] fpu: Check for default_nan_mode before calling pickNaNMulAdd If the target sets default_nan_mode then we're always going to return the default NaN, and pickNaNMulAdd() no longer has any side effects. For consistency with pickNaN(), check for default_nan_mode before calling pickNaNMulAdd(). When we convert pickNaNMulAdd() to allow runtime selection of the NaN propagation rule, this means we won't have to make the targets which use default_nan_mode also set a propagation rule. Since RiscV always uses default_nan_mode, this allows us to remove its ifdef case from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-3-peter.maydell@linaro.org --- fpu/softfloat-parts.c.inc | 8 ++++++-- fpu/softfloat-specialize.c.inc | 9 +++++++-- 2 files changed, 13 insertions(+), 4 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index d63cd957a1..aac1f9cd28 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -77,9 +77,13 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, float_raise(float_flag_invalid | float_flag_invalid_imz, s); } - which = pickNaNMulAdd(a->cls, b->cls, c->cls, infzero, s); + if (s->default_nan_mode) { + which = 3; + } else { + which = pickNaNMulAdd(a->cls, b->cls, c->cls, infzero, s); + } - if (s->default_nan_mode || which == 3) { + if (which == 3) { parts_default_nan(a, s); return a; } diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index c557c41b2a..81a67eb67b 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -475,6 +475,13 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls, static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, bool infzero, float_status *status) { + /* + * We guarantee not to require the target to tell us how to + * pick a NaN if we're always returning the default NaN. + * But if we're not in default-NaN mode then the target must + * specify. + */ + assert(!status->default_nan_mode); #if defined(TARGET_ARM) /* For ARM, the (inf,zero,qnan) case sets InvalidOp and returns * the default NaN @@ -578,8 +585,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } else { return 1; } -#elif defined(TARGET_RISCV) - return 3; /* default NaN */ #elif defined(TARGET_S390X) if (infzero) { return 3; From 4080eebd7357261dce0993e17ec6b6e9efa29581 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:53 +0000 Subject: [PATCH 08/72] softfloat: Allow runtime choice of inf * 0 + NaN result IEEE 758 does not define a fixed rule for what NaN to return in the case of a fused multiply-add of inf * 0 + NaN. Different architectures thus do different things: * some return the default NaN * some return the input NaN * Arm returns the default NaN if the input NaN is quiet, and the input NaN if it is signalling We want to make this logic be runtime selected rather than hardcoded into the binary, because: * this will let us have multiple targets in one QEMU binary * the Arm FEAT_AFP architectural feature includes letting the guest select a NaN propagation rule at runtime In this commit we add an enum for the propagation rule, the field in float_status, and the corresponding getters and setters. We change pickNaNMulAdd to honour this, but because all targets still leave this field at its default 0 value, the fallback logic will pick the rule type with the old ifdef ladder. Note that four architectures both use the muladd softfloat functions and did not have a branch of the ifdef ladder to specify their behaviour (and so were ending up with the "default" case, probably wrongly): i386, HPPA, SH4 and Tricore. SH4 and Tricore both set default_nan_mode, and so will never get into pickNaNMulAdd(). For HPPA and i386 we retain the same behaviour as the old default-case, which is to not ever return the default NaN. This might not be correct but it is not a behaviour change. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-4-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 91 ++++++++++++++++++++++----------- include/fpu/softfloat-helpers.h | 11 ++++ include/fpu/softfloat-types.h | 23 +++++++++ 3 files changed, 95 insertions(+), 30 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 81a67eb67b..f5b422e07b 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -475,6 +475,8 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls, static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, bool infzero, float_status *status) { + FloatInfZeroNaNRule rule = status->float_infzeronan_rule; + /* * We guarantee not to require the target to tell us how to * pick a NaN if we're always returning the default NaN. @@ -482,14 +484,68 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * specify. */ assert(!status->default_nan_mode); + + if (rule == float_infzeronan_none) { + /* + * Temporarily fall back to ifdef ladder + */ #if defined(TARGET_ARM) - /* For ARM, the (inf,zero,qnan) case sets InvalidOp and returns - * the default NaN - */ - if (infzero && is_qnan(c_cls)) { - return 3; + /* + * For ARM, the (inf,zero,qnan) case returns the default NaN, + * but (inf,zero,snan) returns the input NaN. + */ + rule = float_infzeronan_dnan_if_qnan; +#elif defined(TARGET_MIPS) + if (snan_bit_is_one(status)) { + /* + * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan) + * case sets InvalidOp and returns the default NaN + */ + rule = float_infzeronan_dnan_always; + } else { + /* + * For MIPS systems that conform to IEEE754-2008, the (inf,zero,nan) + * case sets InvalidOp and returns the input value 'c' + */ + rule = float_infzeronan_dnan_never; + } +#elif defined(TARGET_PPC) || defined(TARGET_SPARC) || \ + defined(TARGET_XTENSA) || defined(TARGET_HPPA) || \ + defined(TARGET_I386) || defined(TARGET_LOONGARCH) + /* + * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) + * case sets InvalidOp and returns the input value 'c' + */ + /* + * For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer + * to return an input NaN if we have one (ie c) rather than generating + * a default NaN + */ + rule = float_infzeronan_dnan_never; +#elif defined(TARGET_S390X) + rule = float_infzeronan_dnan_always; +#endif } + if (infzero) { + /* + * Inf * 0 + NaN -- some implementations return the default NaN here, + * and some return the input NaN. + */ + switch (rule) { + case float_infzeronan_dnan_never: + return 2; + case float_infzeronan_dnan_always: + return 3; + case float_infzeronan_dnan_if_qnan: + return is_qnan(c_cls) ? 3 : 2; + default: + g_assert_not_reached(); + } + } + +#if defined(TARGET_ARM) + /* This looks different from the ARM ARM pseudocode, because the ARM ARM * puts the operands to a fused mac operation (a*b)+c in the order c,a,b. */ @@ -508,13 +564,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } #elif defined(TARGET_MIPS) if (snan_bit_is_one(status)) { - /* - * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan) - * case sets InvalidOp and returns the default NaN - */ - if (infzero) { - return 3; - } /* Prefer sNaN over qNaN, in the a, b, c order. */ if (is_snan(a_cls)) { return 0; @@ -530,10 +579,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, return 2; } } else { - /* - * For MIPS systems that conform to IEEE754-2008, the (inf,zero,nan) - * case sets InvalidOp and returns the input value 'c' - */ /* Prefer sNaN over qNaN, in the c, a, b order. */ if (is_snan(c_cls)) { return 2; @@ -550,11 +595,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } } #elif defined(TARGET_LOONGARCH64) - /* - * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) - * case sets InvalidOp and returns the input value 'c' - */ - /* Prefer sNaN over qNaN, in the c, a, b order. */ if (is_snan(c_cls)) { return 2; @@ -570,11 +610,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, return 1; } #elif defined(TARGET_PPC) - /* For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer - * to return an input NaN if we have one (ie c) rather than generating - * a default NaN - */ - /* If fRA is a NaN return it; otherwise if fRB is a NaN return it; * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB */ @@ -586,10 +621,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, return 1; } #elif defined(TARGET_S390X) - if (infzero) { - return 3; - } - if (is_snan(a_cls)) { return 0; } else if (is_snan(b_cls)) { diff --git a/include/fpu/softfloat-helpers.h b/include/fpu/softfloat-helpers.h index 453188de70..0bf44dc608 100644 --- a/include/fpu/softfloat-helpers.h +++ b/include/fpu/softfloat-helpers.h @@ -81,6 +81,12 @@ static inline void set_float_2nan_prop_rule(Float2NaNPropRule rule, status->float_2nan_prop_rule = rule; } +static inline void set_float_infzeronan_rule(FloatInfZeroNaNRule rule, + float_status *status) +{ + status->float_infzeronan_rule = rule; +} + static inline void set_flush_to_zero(bool val, float_status *status) { status->flush_to_zero = val; @@ -137,6 +143,11 @@ static inline Float2NaNPropRule get_float_2nan_prop_rule(float_status *status) return status->float_2nan_prop_rule; } +static inline FloatInfZeroNaNRule get_float_infzeronan_rule(float_status *status) +{ + return status->float_infzeronan_rule; +} + static inline bool get_flush_to_zero(float_status *status) { return status->flush_to_zero; diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index 8f39691dfd..47bb22c4e2 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -207,6 +207,28 @@ typedef enum __attribute__((__packed__)) { float_2nan_prop_x87, } Float2NaNPropRule; +/* + * Rule for result of fused multiply-add 0 * Inf + NaN. + * This must be a NaN, but implementations differ on whether this + * is the input NaN or the default NaN. + * + * You don't need to set this if default_nan_mode is enabled. + * When not in default-NaN mode, it is an error for the target + * not to set the rule in float_status if it uses muladd, and we + * will assert if we need to handle an input NaN and no rule was + * selected. + */ +typedef enum __attribute__((__packed__)) { + /* No propagation rule specified */ + float_infzeronan_none = 0, + /* Result is never the default NaN (so always the input NaN) */ + float_infzeronan_dnan_never, + /* Result is always the default NaN */ + float_infzeronan_dnan_always, + /* Result is the default NaN if the input NaN is quiet */ + float_infzeronan_dnan_if_qnan, +} FloatInfZeroNaNRule; + /* * Floating Point Status. Individual architectures may maintain * several versions of float_status for different functions. The @@ -219,6 +241,7 @@ typedef struct float_status { FloatRoundMode float_rounding_mode; FloatX80RoundPrec floatx80_rounding_precision; Float2NaNPropRule float_2nan_prop_rule; + FloatInfZeroNaNRule float_infzeronan_rule; bool tininess_before_rounding; /* should denormalised results go to zero and set the inexact flag? */ bool flush_to_zero; From 27aedf7d25e148089bb54eb80588bd380483cbe5 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:53 +0000 Subject: [PATCH 09/72] tests/fp: Explicitly set inf-zero-nan rule Explicitly set a rule in the softfloat tests for the inf-zero-nan muladd special case. In meson.build we put -DTARGET_ARM in fpcflags, and so we should select here the Arm rule of float_infzeronan_dnan_if_qnan. Reviewed-by: Richard Henderson Signed-off-by: Peter Maydell Message-id: 20241202131347.498124-5-peter.maydell@linaro.org --- tests/fp/fp-bench.c | 5 +++++ tests/fp/fp-test.c | 5 +++++ 2 files changed, 10 insertions(+) diff --git a/tests/fp/fp-bench.c b/tests/fp/fp-bench.c index 75c07d5d1f..fde6483619 100644 --- a/tests/fp/fp-bench.c +++ b/tests/fp/fp-bench.c @@ -488,7 +488,12 @@ static void run_bench(void) { bench_func_t f; + /* + * These implementation-defined choices for various things IEEE + * doesn't specify match those used by the Arm architecture. + */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &soft_status); + set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, &soft_status); f = bench_funcs[operation][precision]; g_assert(f); diff --git a/tests/fp/fp-test.c b/tests/fp/fp-test.c index 5f6f25c882..251c278ede 100644 --- a/tests/fp/fp-test.c +++ b/tests/fp/fp-test.c @@ -935,7 +935,12 @@ void run_test(void) { unsigned int i; + /* + * These implementation-defined choices for various things IEEE + * doesn't specify match those used by the Arm architecture. + */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &qsf); + set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, &qsf); genCases_setLevel(test_level); verCases_maxErrorCount = n_max_errors; From f7892f9c0094c911e5f3ad03072130caf9a1db52 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:53 +0000 Subject: [PATCH 10/72] target/arm: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the Arm target, so we can remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-6-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 8 +------- target/arm/cpu.c | 3 +++ 2 files changed, 4 insertions(+), 7 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index f5b422e07b..b3ffa54f36 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -489,13 +489,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, /* * Temporarily fall back to ifdef ladder */ -#if defined(TARGET_ARM) - /* - * For ARM, the (inf,zero,qnan) case returns the default NaN, - * but (inf,zero,snan) returns the input NaN. - */ - rule = float_infzeronan_dnan_if_qnan; -#elif defined(TARGET_MIPS) +#if defined(TARGET_MIPS) if (snan_bit_is_one(status)) { /* * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan) diff --git a/target/arm/cpu.c b/target/arm/cpu.c index 6938161b95..ead3979398 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -173,11 +173,14 @@ void arm_register_el_change_hook(ARMCPU *cpu, ARMELChangeHookFn *hook, * * tininess-before-rounding * * 2-input NaN propagation prefers SNaN over QNaN, and then * operand A over operand B (see FPProcessNaNs() pseudocode) + * * 0 * Inf + NaN returns the default NaN if the input NaN is quiet, + * and the input NaN if it is signalling */ static void arm_set_default_fp_behaviours(float_status *s) { set_float_detect_tininess(float_tininess_before_rounding, s); set_float_2nan_prop_rule(float_2nan_prop_s_ab, s); + set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, s); } static void cp_reg_reset(gpointer key, gpointer value, gpointer opaque) From e494fe4909fd0e0d61b32af7a86050191187b60d Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:54 +0000 Subject: [PATCH 11/72] target/s390: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for s390, so we can remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-7-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 -- target/s390x/cpu.c | 2 ++ 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index b3ffa54f36..db914ddbb1 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -516,8 +516,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * a default NaN */ rule = float_infzeronan_dnan_never; -#elif defined(TARGET_S390X) - rule = float_infzeronan_dnan_always; #endif } diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c index 514c70f301..d5941b5b9d 100644 --- a/target/s390x/cpu.c +++ b/target/s390x/cpu.c @@ -206,6 +206,8 @@ static void s390_cpu_reset_hold(Object *obj, ResetType type) set_float_detect_tininess(float_tininess_before_rounding, &env->fpu_status); set_float_2nan_prop_rule(float_2nan_prop_s_ab, &env->fpu_status); + set_float_infzeronan_rule(float_infzeronan_dnan_always, + &env->fpu_status); /* fall through */ case RESET_TYPE_S390_CPU_NORMAL: env->psw.mask &= ~PSW_MASK_RI; From 6f759b179fd72a90fed129721dc28e04fa79d7c3 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:54 +0000 Subject: [PATCH 12/72] target/ppc: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the PPC target, so we can remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-8-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 7 +------ target/ppc/cpu_init.c | 7 +++++++ 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index db914ddbb1..2023b2bd63 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -503,18 +503,13 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, */ rule = float_infzeronan_dnan_never; } -#elif defined(TARGET_PPC) || defined(TARGET_SPARC) || \ +#elif defined(TARGET_SPARC) || \ defined(TARGET_XTENSA) || defined(TARGET_HPPA) || \ defined(TARGET_I386) || defined(TARGET_LOONGARCH) /* * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) * case sets InvalidOp and returns the input value 'c' */ - /* - * For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer - * to return an input NaN if we have one (ie c) rather than generating - * a default NaN - */ rule = float_infzeronan_dnan_never; #endif } diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c index efcb80d1c2..f18908a643 100644 --- a/target/ppc/cpu_init.c +++ b/target/ppc/cpu_init.c @@ -7270,6 +7270,13 @@ static void ppc_cpu_reset_hold(Object *obj, ResetType type) */ set_float_2nan_prop_rule(float_2nan_prop_ab, &env->fp_status); set_float_2nan_prop_rule(float_2nan_prop_ab, &env->vec_status); + /* + * For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer + * to return an input NaN if we have one (ie c) rather than generating + * a default NaN + */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->vec_status); for (i = 0; i < ARRAY_SIZE(env->spr_cb); i++) { ppc_spr_t *spr = &env->spr_cb[i]; From a71492f7267490e3cc238fa00662d29a0762fd3a Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:54 +0000 Subject: [PATCH 13/72] target/mips: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the MIPS target, so we can remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-9-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 16 +--------------- target/mips/fpu_helper.h | 9 +++++++++ target/mips/msa.c | 4 ++++ 3 files changed, 14 insertions(+), 15 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 2023b2bd63..db9a466e05 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -489,21 +489,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, /* * Temporarily fall back to ifdef ladder */ -#if defined(TARGET_MIPS) - if (snan_bit_is_one(status)) { - /* - * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan) - * case sets InvalidOp and returns the default NaN - */ - rule = float_infzeronan_dnan_always; - } else { - /* - * For MIPS systems that conform to IEEE754-2008, the (inf,zero,nan) - * case sets InvalidOp and returns the input value 'c' - */ - rule = float_infzeronan_dnan_never; - } -#elif defined(TARGET_SPARC) || \ +#if defined(TARGET_SPARC) || \ defined(TARGET_XTENSA) || defined(TARGET_HPPA) || \ defined(TARGET_I386) || defined(TARGET_LOONGARCH) /* diff --git a/target/mips/fpu_helper.h b/target/mips/fpu_helper.h index 7c3c7897b4..be66f2f813 100644 --- a/target/mips/fpu_helper.h +++ b/target/mips/fpu_helper.h @@ -28,6 +28,7 @@ static inline void restore_flush_mode(CPUMIPSState *env) static inline void restore_snan_bit_mode(CPUMIPSState *env) { bool nan2008 = env->active_fpu.fcr31 & (1 << FCR31_NAN2008); + FloatInfZeroNaNRule izn_rule; /* * With nan2008, SNaNs are silenced in the usual way. @@ -35,6 +36,14 @@ static inline void restore_snan_bit_mode(CPUMIPSState *env) */ set_snan_bit_is_one(!nan2008, &env->active_fpu.fp_status); set_default_nan_mode(!nan2008, &env->active_fpu.fp_status); + /* + * For MIPS systems that conform to IEEE754-1985, the (inf,zero,nan) + * case sets InvalidOp and returns the default NaN. + * For MIPS systems that conform to IEEE754-2008, the (inf,zero,nan) + * case sets InvalidOp and returns the input value 'c'. + */ + izn_rule = nan2008 ? float_infzeronan_dnan_never : float_infzeronan_dnan_always; + set_float_infzeronan_rule(izn_rule, &env->active_fpu.fp_status); } static inline void restore_fp_status(CPUMIPSState *env) diff --git a/target/mips/msa.c b/target/mips/msa.c index 9dffc428f5..cc152db27f 100644 --- a/target/mips/msa.c +++ b/target/mips/msa.c @@ -74,4 +74,8 @@ void msa_reset(CPUMIPSState *env) /* set proper signanling bit meaning ("1" means "quiet") */ set_snan_bit_is_one(0, &env->active_tc.msa_fp_status); + + /* Inf * 0 + NaN returns the input NaN */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, + &env->active_tc.msa_fp_status); } From 9a31b8d0ad86e12920e01bd4c01516be9f75337e Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:55 +0000 Subject: [PATCH 14/72] target/sparc: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the SPARC target, so we can remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-10-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 3 +-- target/sparc/cpu.c | 2 ++ 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index db9a466e05..7e57e85348 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -489,8 +489,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, /* * Temporarily fall back to ifdef ladder */ -#if defined(TARGET_SPARC) || \ - defined(TARGET_XTENSA) || defined(TARGET_HPPA) || \ +#if defined(TARGET_XTENSA) || defined(TARGET_HPPA) || \ defined(TARGET_I386) || defined(TARGET_LOONGARCH) /* * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) diff --git a/target/sparc/cpu.c b/target/sparc/cpu.c index dd7af86de7..61f2d3fbf2 100644 --- a/target/sparc/cpu.c +++ b/target/sparc/cpu.c @@ -814,6 +814,8 @@ static void sparc_cpu_realizefn(DeviceState *dev, Error **errp) * the CPU state struct so it won't get zeroed on reset. */ set_float_2nan_prop_rule(float_2nan_prop_s_ba, &env->fp_status); + /* For inf * 0 + NaN, return the input NaN */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); cpu_exec_realizefn(cs, &local_err); if (local_err != NULL) { From 67c0df045ec11da24bd2f18f81813ed9ff48b4c5 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:55 +0000 Subject: [PATCH 15/72] target/xtensa: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the xtensa target, so we can remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-11-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 +- target/xtensa/cpu.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 7e57e85348..3062d19402 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -489,7 +489,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, /* * Temporarily fall back to ifdef ladder */ -#if defined(TARGET_XTENSA) || defined(TARGET_HPPA) || \ +#if defined(TARGET_HPPA) || \ defined(TARGET_I386) || defined(TARGET_LOONGARCH) /* * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) diff --git a/target/xtensa/cpu.c b/target/xtensa/cpu.c index 6f9039abae..3163b75823 100644 --- a/target/xtensa/cpu.c +++ b/target/xtensa/cpu.c @@ -133,6 +133,8 @@ static void xtensa_cpu_reset_hold(Object *obj, ResetType type) reset_mmu(env); cs->halted = env->runstall; #endif + /* For inf * 0 + NaN, return the input NaN */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); set_no_signaling_nans(!dfpu, &env->fp_status); xtensa_use_first_nan(env, !dfpu); } From 390df9046b58249dfac2590a914422834c8333c6 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:55 +0000 Subject: [PATCH 16/72] target/x86: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the x86 target. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-12-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 +- target/i386/tcg/fpu_helper.c | 7 +++++++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 3062d19402..ad4f7096d0 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -490,7 +490,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, * Temporarily fall back to ifdef ladder */ #if defined(TARGET_HPPA) || \ - defined(TARGET_I386) || defined(TARGET_LOONGARCH) + defined(TARGET_LOONGARCH) /* * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) * case sets InvalidOp and returns the input value 'c' diff --git a/target/i386/tcg/fpu_helper.c b/target/i386/tcg/fpu_helper.c index 53b49bb297..3295753e07 100644 --- a/target/i386/tcg/fpu_helper.c +++ b/target/i386/tcg/fpu_helper.c @@ -173,6 +173,13 @@ void cpu_init_fp_statuses(CPUX86State *env) */ set_float_2nan_prop_rule(float_2nan_prop_x87, &env->mmx_status); set_float_2nan_prop_rule(float_2nan_prop_x87, &env->sse_status); + /* + * Only SSE has multiply-add instructions. In the SDM Section 14.5.2 + * "Fused-Multiply-ADD (FMA) Numeric Behavior" the NaN handling is + * specified -- for 0 * inf + NaN the input NaN is selected, and if + * there are multiple input NaNs they are selected in the order a, b, c. + */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->sse_status); } static inline uint8_t save_exception_flags(CPUX86State *env) From 0fb7fa29d3c4a21bf5daf7f30c70f916e878935c Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:56 +0000 Subject: [PATCH 17/72] target/loongarch: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the loongarch target. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-13-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 7 +------ target/loongarch/tcg/fpu_helper.c | 5 +++++ 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index ad4f7096d0..05dec2fcb4 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -489,12 +489,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, /* * Temporarily fall back to ifdef ladder */ -#if defined(TARGET_HPPA) || \ - defined(TARGET_LOONGARCH) - /* - * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) - * case sets InvalidOp and returns the input value 'c' - */ +#if defined(TARGET_HPPA) rule = float_infzeronan_dnan_never; #endif } diff --git a/target/loongarch/tcg/fpu_helper.c b/target/loongarch/tcg/fpu_helper.c index 21bc3b04a9..6a2c4b5b1d 100644 --- a/target/loongarch/tcg/fpu_helper.c +++ b/target/loongarch/tcg/fpu_helper.c @@ -32,6 +32,11 @@ void restore_fp_status(CPULoongArchState *env) &env->fp_status); set_flush_to_zero(0, &env->fp_status); set_float_2nan_prop_rule(float_2nan_prop_s_ab, &env->fp_status); + /* + * For LoongArch systems that conform to IEEE754-2008, the (inf,zero,nan) + * case sets InvalidOp and returns the input value 'c' + */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); } int ieee_ex_to_loongarch(int xcpt) From 2bf5629c97af5aa57f8524af92f5459f1d2ceeac Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:56 +0000 Subject: [PATCH 18/72] target/hppa: Set FloatInfZeroNaNRule explicitly Set the FloatInfZeroNaNRule explicitly for the HPPA target, so we can remove the ifdef from pickNaNMulAdd(). As this is the last target to be converted to explicitly setting the rule, we can remove the fallback code in pickNaNMulAdd() entirely. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-14-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 13 +------------ target/hppa/fpu_helper.c | 2 ++ 2 files changed, 3 insertions(+), 12 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 05dec2fcb4..3e4ec938b2 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -475,8 +475,6 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls, static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, bool infzero, float_status *status) { - FloatInfZeroNaNRule rule = status->float_infzeronan_rule; - /* * We guarantee not to require the target to tell us how to * pick a NaN if we're always returning the default NaN. @@ -485,21 +483,12 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, */ assert(!status->default_nan_mode); - if (rule == float_infzeronan_none) { - /* - * Temporarily fall back to ifdef ladder - */ -#if defined(TARGET_HPPA) - rule = float_infzeronan_dnan_never; -#endif - } - if (infzero) { /* * Inf * 0 + NaN -- some implementations return the default NaN here, * and some return the input NaN. */ - switch (rule) { + switch (status->float_infzeronan_rule) { case float_infzeronan_dnan_never: return 2; case float_infzeronan_dnan_always: diff --git a/target/hppa/fpu_helper.c b/target/hppa/fpu_helper.c index 0e44074ba8..393cae33bf 100644 --- a/target/hppa/fpu_helper.c +++ b/target/hppa/fpu_helper.c @@ -55,6 +55,8 @@ void HELPER(loaded_fr0)(CPUHPPAState *env) * HPPA does note implement a CPU reset method at all... */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &env->fp_status); + /* For inf * 0 + NaN, return the input NaN */ + set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); } void cpu_hppa_loaded_fr0(CPUHPPAState *env) From d62c734d52147ec312d1ada0e1bc7fa479838575 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 19/72] softfloat: Pass have_snan to pickNaNMulAdd The new implementation of pickNaNMulAdd() will find it convenient to know whether at least one of the three arguments to the muladd was a signaling NaN. We already calculate that in the caller, so pass it in as a new bool have_snan. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-15-peter.maydell@linaro.org --- fpu/softfloat-parts.c.inc | 5 +++-- fpu/softfloat-specialize.c.inc | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index aac1f9cd28..655b7d9da5 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -67,8 +67,9 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, { int which; bool infzero = (ab_mask == float_cmask_infzero); + bool have_snan = (abc_mask & float_cmask_snan); - if (unlikely(abc_mask & float_cmask_snan)) { + if (unlikely(have_snan)) { float_raise(float_flag_invalid | float_flag_invalid_snan, s); } @@ -80,7 +81,7 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, if (s->default_nan_mode) { which = 3; } else { - which = pickNaNMulAdd(a->cls, b->cls, c->cls, infzero, s); + which = pickNaNMulAdd(a->cls, b->cls, c->cls, infzero, have_snan, s); } if (which == 3) { diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 3e4ec938b2..a769c71f54 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -473,7 +473,7 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls, | Return values : 0 : a; 1 : b; 2 : c; 3 : default-NaN *----------------------------------------------------------------------------*/ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, - bool infzero, float_status *status) + bool infzero, bool have_snan, float_status *status) { /* * We guarantee not to require the target to tell us how to From 7a944c30f72380e543b58342e12105dcf98d8496 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 20/72] softfloat: Allow runtime choice of NaN propagation for muladd IEEE 758 does not define a fixed rule for which NaN to pick as the result if both operands of a 3-operand fused multiply-add operation are NaNs. As a result different architectures have ended up with different rules for propagating NaNs. QEMU currently hardcodes the NaN propagation logic into the binary because pickNaNMulAdd() has an ifdef ladder for different targets. We want to make the propagation rule instead be selectable at runtime, because: * this will let us have multiple targets in one QEMU binary * the Arm FEAT_AFP architectural feature includes letting the guest select a NaN propagation rule at runtime In this commit we add an enum for the propagation rule, the field in float_status, and the corresponding getters and setters. We change pickNaNMulAdd to honour this, but because all targets still leave this field at its default 0 value, the fallback logic will pick the rule type with the old ifdef ladder. It's valid not to set a propagation rule if default_nan_mode is enabled, because in that case there's no need to pick a NaN; all the callers of pickNaNMulAdd() catch this case and skip calling it. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-16-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 167 ++++++++------------------------ include/fpu/softfloat-helpers.h | 11 +++ include/fpu/softfloat-types.h | 55 +++++++++++ 3 files changed, 107 insertions(+), 126 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index a769c71f54..b4f3f0efa8 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -475,6 +475,10 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls, static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, bool infzero, bool have_snan, float_status *status) { + FloatClass cls[3] = { a_cls, b_cls, c_cls }; + Float3NaNPropRule rule = status->float_3nan_prop_rule; + int which; + /* * We guarantee not to require the target to tell us how to * pick a NaN if we're always returning the default NaN. @@ -500,145 +504,56 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } } + if (rule == float_3nan_prop_none) { #if defined(TARGET_ARM) - - /* This looks different from the ARM ARM pseudocode, because the ARM ARM - * puts the operands to a fused mac operation (a*b)+c in the order c,a,b. - */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } + /* + * This looks different from the ARM ARM pseudocode, because the ARM ARM + * puts the operands to a fused mac operation (a*b)+c in the order c,a,b + */ + rule = float_3nan_prop_s_cab; #elif defined(TARGET_MIPS) - if (snan_bit_is_one(status)) { - /* Prefer sNaN over qNaN, in the a, b, c order. */ - if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_snan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else if (is_qnan(b_cls)) { - return 1; + if (snan_bit_is_one(status)) { + rule = float_3nan_prop_s_abc; } else { - return 2; + rule = float_3nan_prop_s_cab; } - } else { - /* Prefer sNaN over qNaN, in the c, a, b order. */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } - } #elif defined(TARGET_LOONGARCH64) - /* Prefer sNaN over qNaN, in the c, a, b order. */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } + rule = float_3nan_prop_s_cab; #elif defined(TARGET_PPC) - /* If fRA is a NaN return it; otherwise if fRB is a NaN return it; - * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB - */ - if (is_nan(a_cls)) { - return 0; - } else if (is_nan(c_cls)) { - return 2; - } else { - return 1; - } + /* + * If fRA is a NaN return it; otherwise if fRB is a NaN return it; + * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB + */ + rule = float_3nan_prop_acb; #elif defined(TARGET_S390X) - if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_snan(c_cls)) { - return 2; - } else if (is_qnan(a_cls)) { - return 0; - } else if (is_qnan(b_cls)) { - return 1; - } else { - return 2; - } + rule = float_3nan_prop_s_abc; #elif defined(TARGET_SPARC) - /* Prefer SNaN over QNaN, order C, B, A. */ - if (is_snan(c_cls)) { - return 2; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_qnan(c_cls)) { - return 2; - } else if (is_qnan(b_cls)) { - return 1; - } else { - return 0; - } + rule = float_3nan_prop_s_cba; #elif defined(TARGET_XTENSA) - /* - * For Xtensa, the (inf,zero,nan) case sets InvalidOp and returns - * an input NaN if we have one (ie c). - */ - if (status->use_first_nan) { - if (is_nan(a_cls)) { - return 0; - } else if (is_nan(b_cls)) { - return 1; + if (status->use_first_nan) { + rule = float_3nan_prop_abc; } else { - return 2; + rule = float_3nan_prop_cba; } - } else { - if (is_nan(c_cls)) { - return 2; - } else if (is_nan(b_cls)) { - return 1; - } else { - return 0; - } - } #else - /* A default implementation: prefer a to b to c. - * This is unlikely to actually match any real implementation. - */ - if (is_nan(a_cls)) { - return 0; - } else if (is_nan(b_cls)) { - return 1; - } else { - return 2; - } + rule = float_3nan_prop_abc; #endif + } + + assert(rule != float_3nan_prop_none); + if (have_snan && (rule & R_3NAN_SNAN_MASK)) { + /* We have at least one SNaN input and should prefer it */ + do { + which = rule & R_3NAN_1ST_MASK; + rule >>= R_3NAN_1ST_LENGTH; + } while (!is_snan(cls[which])); + } else { + do { + which = rule & R_3NAN_1ST_MASK; + rule >>= R_3NAN_1ST_LENGTH; + } while (!is_nan(cls[which])); + } + return which; } /*---------------------------------------------------------------------------- diff --git a/include/fpu/softfloat-helpers.h b/include/fpu/softfloat-helpers.h index 0bf44dc608..cf06b4e16b 100644 --- a/include/fpu/softfloat-helpers.h +++ b/include/fpu/softfloat-helpers.h @@ -81,6 +81,12 @@ static inline void set_float_2nan_prop_rule(Float2NaNPropRule rule, status->float_2nan_prop_rule = rule; } +static inline void set_float_3nan_prop_rule(Float3NaNPropRule rule, + float_status *status) +{ + status->float_3nan_prop_rule = rule; +} + static inline void set_float_infzeronan_rule(FloatInfZeroNaNRule rule, float_status *status) { @@ -143,6 +149,11 @@ static inline Float2NaNPropRule get_float_2nan_prop_rule(float_status *status) return status->float_2nan_prop_rule; } +static inline Float3NaNPropRule get_float_3nan_prop_rule(float_status *status) +{ + return status->float_3nan_prop_rule; +} + static inline FloatInfZeroNaNRule get_float_infzeronan_rule(float_status *status) { return status->float_infzeronan_rule; diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index 47bb22c4e2..d9f0797eda 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -80,6 +80,8 @@ this code that are retained. #ifndef SOFTFLOAT_TYPES_H #define SOFTFLOAT_TYPES_H +#include "hw/registerfields.h" + /* * Software IEC/IEEE floating-point types. */ @@ -207,6 +209,58 @@ typedef enum __attribute__((__packed__)) { float_2nan_prop_x87, } Float2NaNPropRule; +/* + * 3-input NaN propagation rule, for fused multiply-add. Individual + * architectures have different rules for which input NaN is + * propagated to the output when there is more than one NaN on the + * input. + * + * If default_nan_mode is enabled then it is valid not to set a NaN + * propagation rule, because the softfloat code guarantees not to try + * to pick a NaN to propagate in default NaN mode. When not in + * default-NaN mode, it is an error for the target not to set the rule + * in float_status if it uses a muladd, and we will assert if we need + * to handle an input NaN and no rule was selected. + * + * The naming scheme for Float3NaNPropRule values is: + * float_3nan_prop_s_abc: + * = "Prefer SNaN over QNaN, then operand A over B over C" + * float_3nan_prop_abc: + * = "Prefer A over B over C regardless of SNaN vs QNAN" + * + * For QEMU, the multiply-add operation is A * B + C. + */ + +/* + * We set the Float3NaNPropRule enum values up so we can select the + * right value in pickNaNMulAdd in a data driven way. + */ +FIELD(3NAN, 1ST, 0, 2) /* which operand is most preferred ? */ +FIELD(3NAN, 2ND, 2, 2) /* which operand is next most preferred ? */ +FIELD(3NAN, 3RD, 4, 2) /* which operand is least preferred ? */ +FIELD(3NAN, SNAN, 6, 1) /* do we prefer SNaN over QNaN ? */ + +#define PROPRULE(X, Y, Z) \ + ((X << R_3NAN_1ST_SHIFT) | (Y << R_3NAN_2ND_SHIFT) | (Z << R_3NAN_3RD_SHIFT)) + +typedef enum __attribute__((__packed__)) { + float_3nan_prop_none = 0, /* No propagation rule specified */ + float_3nan_prop_abc = PROPRULE(0, 1, 2), + float_3nan_prop_acb = PROPRULE(0, 2, 1), + float_3nan_prop_bac = PROPRULE(1, 0, 2), + float_3nan_prop_bca = PROPRULE(1, 2, 0), + float_3nan_prop_cab = PROPRULE(2, 0, 1), + float_3nan_prop_cba = PROPRULE(2, 1, 0), + float_3nan_prop_s_abc = float_3nan_prop_abc | R_3NAN_SNAN_MASK, + float_3nan_prop_s_acb = float_3nan_prop_acb | R_3NAN_SNAN_MASK, + float_3nan_prop_s_bac = float_3nan_prop_bac | R_3NAN_SNAN_MASK, + float_3nan_prop_s_bca = float_3nan_prop_bca | R_3NAN_SNAN_MASK, + float_3nan_prop_s_cab = float_3nan_prop_cab | R_3NAN_SNAN_MASK, + float_3nan_prop_s_cba = float_3nan_prop_cba | R_3NAN_SNAN_MASK, +} Float3NaNPropRule; + +#undef PROPRULE + /* * Rule for result of fused multiply-add 0 * Inf + NaN. * This must be a NaN, but implementations differ on whether this @@ -241,6 +295,7 @@ typedef struct float_status { FloatRoundMode float_rounding_mode; FloatX80RoundPrec floatx80_rounding_precision; Float2NaNPropRule float_2nan_prop_rule; + Float3NaNPropRule float_3nan_prop_rule; FloatInfZeroNaNRule float_infzeronan_rule; bool tininess_before_rounding; /* should denormalised results go to zero and set the inexact flag? */ From 43e51128083185ec5deb2cbe322fb851f7e2d2ae Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 21/72] tests/fp: Explicitly set 3-NaN propagation rule Explicitly set a rule in the softfloat tests for propagating NaNs in the muladd case. In meson.build we put -DTARGET_ARM in fpcflags, and so we should select here the Arm rule of float_3nan_prop_s_cab. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-17-peter.maydell@linaro.org --- tests/fp/fp-bench.c | 1 + tests/fp/fp-test.c | 1 + 2 files changed, 2 insertions(+) diff --git a/tests/fp/fp-bench.c b/tests/fp/fp-bench.c index fde6483619..39d80c9038 100644 --- a/tests/fp/fp-bench.c +++ b/tests/fp/fp-bench.c @@ -493,6 +493,7 @@ static void run_bench(void) * doesn't specify match those used by the Arm architecture. */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &soft_status); + set_float_3nan_prop_rule(float_3nan_prop_s_cab, &soft_status); set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, &soft_status); f = bench_funcs[operation][precision]; diff --git a/tests/fp/fp-test.c b/tests/fp/fp-test.c index 251c278ede..f290d523ab 100644 --- a/tests/fp/fp-test.c +++ b/tests/fp/fp-test.c @@ -940,6 +940,7 @@ void run_test(void) * doesn't specify match those used by the Arm architecture. */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &qsf); + set_float_3nan_prop_rule(float_3nan_prop_s_cab, &qsf); set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, &qsf); genCases_setLevel(test_level); From 10519d3b1aeb24d8173631d4fe0ecb91f2732e19 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 22/72] target/arm: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for Arm, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-18-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 8 +------- target/arm/cpu.c | 5 +++++ 2 files changed, 6 insertions(+), 7 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index b4f3f0efa8..3a2d044447 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -505,13 +505,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } if (rule == float_3nan_prop_none) { -#if defined(TARGET_ARM) - /* - * This looks different from the ARM ARM pseudocode, because the ARM ARM - * puts the operands to a fused mac operation (a*b)+c in the order c,a,b - */ - rule = float_3nan_prop_s_cab; -#elif defined(TARGET_MIPS) +#if defined(TARGET_MIPS) if (snan_bit_is_one(status)) { rule = float_3nan_prop_s_abc; } else { diff --git a/target/arm/cpu.c b/target/arm/cpu.c index ead3979398..c81f6df3fc 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -173,6 +173,10 @@ void arm_register_el_change_hook(ARMCPU *cpu, ARMELChangeHookFn *hook, * * tininess-before-rounding * * 2-input NaN propagation prefers SNaN over QNaN, and then * operand A over operand B (see FPProcessNaNs() pseudocode) + * * 3-input NaN propagation prefers SNaN over QNaN, and then + * operand C over A over B (see FPProcessNaNs3() pseudocode, + * but note that for QEMU muladd is a * b + c, whereas for + * the pseudocode function the arguments are in the order c, a, b. * * 0 * Inf + NaN returns the default NaN if the input NaN is quiet, * and the input NaN if it is signalling */ @@ -180,6 +184,7 @@ static void arm_set_default_fp_behaviours(float_status *s) { set_float_detect_tininess(float_tininess_before_rounding, s); set_float_2nan_prop_rule(float_2nan_prop_s_ab, s); + set_float_3nan_prop_rule(float_3nan_prop_s_cab, s); set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, s); } From 9d0b8f96056f45510c3f0ed7216dbc969e5e5fec Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 23/72] target/loongarch: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for loongarch, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-19-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 -- target/loongarch/tcg/fpu_helper.c | 1 + 2 files changed, 1 insertion(+), 2 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 3a2d044447..d610f46002 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -511,8 +511,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } else { rule = float_3nan_prop_s_cab; } -#elif defined(TARGET_LOONGARCH64) - rule = float_3nan_prop_s_cab; #elif defined(TARGET_PPC) /* * If fRA is a NaN return it; otherwise if fRB is a NaN return it; diff --git a/target/loongarch/tcg/fpu_helper.c b/target/loongarch/tcg/fpu_helper.c index 6a2c4b5b1d..37a4859936 100644 --- a/target/loongarch/tcg/fpu_helper.c +++ b/target/loongarch/tcg/fpu_helper.c @@ -37,6 +37,7 @@ void restore_fp_status(CPULoongArchState *env) * case sets InvalidOp and returns the input value 'c' */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); + set_float_3nan_prop_rule(float_3nan_prop_s_cab, &env->fp_status); } int ieee_ex_to_loongarch(int xcpt) From ac1254c4e75cd365283eca90cebc64cdb5a7e48d Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 24/72] target/ppc: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for PPC, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-20-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 6 ------ target/ppc/cpu_init.c | 8 ++++++++ 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index d610f46002..173b9eadb5 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -511,12 +511,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } else { rule = float_3nan_prop_s_cab; } -#elif defined(TARGET_PPC) - /* - * If fRA is a NaN return it; otherwise if fRB is a NaN return it; - * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB - */ - rule = float_3nan_prop_acb; #elif defined(TARGET_S390X) rule = float_3nan_prop_s_abc; #elif defined(TARGET_SPARC) diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c index f18908a643..eb9d7b1370 100644 --- a/target/ppc/cpu_init.c +++ b/target/ppc/cpu_init.c @@ -7270,6 +7270,14 @@ static void ppc_cpu_reset_hold(Object *obj, ResetType type) */ set_float_2nan_prop_rule(float_2nan_prop_ab, &env->fp_status); set_float_2nan_prop_rule(float_2nan_prop_ab, &env->vec_status); + /* + * NaN propagation for fused multiply-add: + * if fRA is a NaN return it; otherwise if fRB is a NaN return it; + * otherwise return fRC. Note that muladd on PPC is (fRA * fRC) + frB + * whereas QEMU labels the operands as (a * b) + c. + */ + set_float_3nan_prop_rule(float_3nan_prop_acb, &env->fp_status); + set_float_3nan_prop_rule(float_3nan_prop_acb, &env->vec_status); /* * For PPC, the (inf,zero,qnan) case sets InvalidOp, but we prefer * to return an input NaN if we have one (ie c) rather than generating From b07039a03e0261105e2de45eb077ede18b3e49b5 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:57 +0000 Subject: [PATCH 25/72] target/s390x: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for s390x, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-21-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 -- target/s390x/cpu.c | 1 + 2 files changed, 1 insertion(+), 2 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 173b9eadb5..8a36280df1 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -511,8 +511,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } else { rule = float_3nan_prop_s_cab; } -#elif defined(TARGET_S390X) - rule = float_3nan_prop_s_abc; #elif defined(TARGET_SPARC) rule = float_3nan_prop_s_cba; #elif defined(TARGET_XTENSA) diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c index d5941b5b9d..e74055bad7 100644 --- a/target/s390x/cpu.c +++ b/target/s390x/cpu.c @@ -206,6 +206,7 @@ static void s390_cpu_reset_hold(Object *obj, ResetType type) set_float_detect_tininess(float_tininess_before_rounding, &env->fpu_status); set_float_2nan_prop_rule(float_2nan_prop_s_ab, &env->fpu_status); + set_float_3nan_prop_rule(float_3nan_prop_s_abc, &env->fpu_status); set_float_infzeronan_rule(float_infzeronan_dnan_always, &env->fpu_status); /* fall through */ From 49866dcb59a28325c99c08745ed8e7c81828ed06 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:58 +0000 Subject: [PATCH 26/72] target/sparc: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for SPARC, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-22-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 -- target/sparc/cpu.c | 2 ++ 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 8a36280df1..c4d8d085a9 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -511,8 +511,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } else { rule = float_3nan_prop_s_cab; } -#elif defined(TARGET_SPARC) - rule = float_3nan_prop_s_cba; #elif defined(TARGET_XTENSA) if (status->use_first_nan) { rule = float_3nan_prop_abc; diff --git a/target/sparc/cpu.c b/target/sparc/cpu.c index 61f2d3fbf2..0f2997a85e 100644 --- a/target/sparc/cpu.c +++ b/target/sparc/cpu.c @@ -814,6 +814,8 @@ static void sparc_cpu_realizefn(DeviceState *dev, Error **errp) * the CPU state struct so it won't get zeroed on reset. */ set_float_2nan_prop_rule(float_2nan_prop_s_ba, &env->fp_status); + /* For fused-multiply add, prefer SNaN over QNaN, then C->B->A */ + set_float_3nan_prop_rule(float_3nan_prop_s_cba, &env->fp_status); /* For inf * 0 + NaN, return the input NaN */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); From 3a45371291af21b9671ac081fae6bec9270c9af7 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:58 +0000 Subject: [PATCH 27/72] target/mips: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for Arm, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-23-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 8 +------- target/mips/fpu_helper.h | 4 ++++ target/mips/msa.c | 3 +++ 3 files changed, 8 insertions(+), 7 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index c4d8d085a9..28db409d22 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -505,13 +505,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } if (rule == float_3nan_prop_none) { -#if defined(TARGET_MIPS) - if (snan_bit_is_one(status)) { - rule = float_3nan_prop_s_abc; - } else { - rule = float_3nan_prop_s_cab; - } -#elif defined(TARGET_XTENSA) +#if defined(TARGET_XTENSA) if (status->use_first_nan) { rule = float_3nan_prop_abc; } else { diff --git a/target/mips/fpu_helper.h b/target/mips/fpu_helper.h index be66f2f813..8ca0ca7ea3 100644 --- a/target/mips/fpu_helper.h +++ b/target/mips/fpu_helper.h @@ -29,6 +29,7 @@ static inline void restore_snan_bit_mode(CPUMIPSState *env) { bool nan2008 = env->active_fpu.fcr31 & (1 << FCR31_NAN2008); FloatInfZeroNaNRule izn_rule; + Float3NaNPropRule nan3_rule; /* * With nan2008, SNaNs are silenced in the usual way. @@ -44,6 +45,9 @@ static inline void restore_snan_bit_mode(CPUMIPSState *env) */ izn_rule = nan2008 ? float_infzeronan_dnan_never : float_infzeronan_dnan_always; set_float_infzeronan_rule(izn_rule, &env->active_fpu.fp_status); + nan3_rule = nan2008 ? float_3nan_prop_s_cab : float_3nan_prop_s_abc; + set_float_3nan_prop_rule(nan3_rule, &env->active_fpu.fp_status); + } static inline void restore_fp_status(CPUMIPSState *env) diff --git a/target/mips/msa.c b/target/mips/msa.c index cc152db27f..93a9a87d76 100644 --- a/target/mips/msa.c +++ b/target/mips/msa.c @@ -66,6 +66,9 @@ void msa_reset(CPUMIPSState *env) set_float_2nan_prop_rule(float_2nan_prop_s_ab, &env->active_tc.msa_fp_status); + set_float_3nan_prop_rule(float_3nan_prop_s_cab, + &env->active_tc.msa_fp_status); + /* clear float_status exception flags */ set_float_exception_flags(0, &env->active_tc.msa_fp_status); From 8e6915645e356a0bc82afd06b4fc5d5c286c9342 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:58 +0000 Subject: [PATCH 28/72] target/xtensa: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for xtensa, and remove the ifdef from pickNaNMulAdd(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-24-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 8 -------- target/xtensa/fpu_helper.c | 2 ++ 2 files changed, 2 insertions(+), 8 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 28db409d22..67428dab98 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -505,15 +505,7 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } if (rule == float_3nan_prop_none) { -#if defined(TARGET_XTENSA) - if (status->use_first_nan) { - rule = float_3nan_prop_abc; - } else { - rule = float_3nan_prop_cba; - } -#else rule = float_3nan_prop_abc; -#endif } assert(rule != float_3nan_prop_none); diff --git a/target/xtensa/fpu_helper.c b/target/xtensa/fpu_helper.c index f2d212d05d..4b1b021d82 100644 --- a/target/xtensa/fpu_helper.c +++ b/target/xtensa/fpu_helper.c @@ -62,6 +62,8 @@ void xtensa_use_first_nan(CPUXtensaState *env, bool use_first) set_use_first_nan(use_first, &env->fp_status); set_float_2nan_prop_rule(use_first ? float_2nan_prop_ab : float_2nan_prop_ba, &env->fp_status); + set_float_3nan_prop_rule(use_first ? float_3nan_prop_abc : float_3nan_prop_cba, + &env->fp_status); } void HELPER(wur_fpu2k_fcr)(CPUXtensaState *env, uint32_t v) From 703990100a34e289716e0a5b4c2bb12a14b32597 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:58 +0000 Subject: [PATCH 29/72] target/i386: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for i386. We had no i386-specific behaviour in the old ifdef ladder, so we were using the default "prefer a then b then c" fallback; this is actually the correct per-the-spec handling for i386. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-25-peter.maydell@linaro.org --- target/i386/tcg/fpu_helper.c | 1 + 1 file changed, 1 insertion(+) diff --git a/target/i386/tcg/fpu_helper.c b/target/i386/tcg/fpu_helper.c index 3295753e07..4303b3356a 100644 --- a/target/i386/tcg/fpu_helper.c +++ b/target/i386/tcg/fpu_helper.c @@ -180,6 +180,7 @@ void cpu_init_fp_statuses(CPUX86State *env) * there are multiple input NaNs they are selected in the order a, b, c. */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->sse_status); + set_float_3nan_prop_rule(float_3nan_prop_abc, &env->sse_status); } static inline uint8_t save_exception_flags(CPUX86State *env) From f8023791f21bf46229ce403566ca476b86e06505 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:59 +0000 Subject: [PATCH 30/72] target/hppa: Set Float3NaNPropRule explicitly Set the Float3NaNPropRule explicitly for HPPA, and remove the ifdef from pickNaNMulAdd(). HPPA is the only target that was using the default branch of the ifdef ladder (other targets either do not use muladd or set default_nan_mode), so we can remove the ifdef fallback entirely now (allowing the "rule not set" case to fall into the default of the switch statement and assert). We add a TODO note that the HPPA rule is probably wrong; this is not a behavioural change for this refactoring. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-26-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 4 ---- target/hppa/fpu_helper.c | 8 ++++++++ 2 files changed, 8 insertions(+), 4 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 67428dab98..5fbc953e71 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -504,10 +504,6 @@ static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, } } - if (rule == float_3nan_prop_none) { - rule = float_3nan_prop_abc; - } - assert(rule != float_3nan_prop_none); if (have_snan && (rule & R_3NAN_SNAN_MASK)) { /* We have at least one SNaN input and should prefer it */ diff --git a/target/hppa/fpu_helper.c b/target/hppa/fpu_helper.c index 393cae33bf..69c4ce3783 100644 --- a/target/hppa/fpu_helper.c +++ b/target/hppa/fpu_helper.c @@ -55,6 +55,14 @@ void HELPER(loaded_fr0)(CPUHPPAState *env) * HPPA does note implement a CPU reset method at all... */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &env->fp_status); + /* + * TODO: The HPPA architecture reference only documents its NaN + * propagation rule for 2-operand operations. Testing on real hardware + * might be necessary to confirm whether this order for muladd is correct. + * Not preferring the SNaN is almost certainly incorrect as it diverges + * from the documented rules for 2-operand operations. + */ + set_float_3nan_prop_rule(float_3nan_prop_abc, &env->fp_status); /* For inf * 0 + NaN, return the input NaN */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); } From dc416d6ca74d43f3aa1bd304d241b9a11d86e184 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:59 +0000 Subject: [PATCH 31/72] fpu: Remove use_first_nan field from float_status The use_first_nan field in float_status was an xtensa-specific way to select at runtime from two different NaN propagation rules. Now that xtensa is using the target-agnostic NaN propagation rule selection that we've just added, we can remove use_first_nan, because there is no longer any code that reads it. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-27-peter.maydell@linaro.org --- include/fpu/softfloat-helpers.h | 5 ----- include/fpu/softfloat-types.h | 1 - target/xtensa/fpu_helper.c | 1 - 3 files changed, 7 deletions(-) diff --git a/include/fpu/softfloat-helpers.h b/include/fpu/softfloat-helpers.h index cf06b4e16b..10a6763532 100644 --- a/include/fpu/softfloat-helpers.h +++ b/include/fpu/softfloat-helpers.h @@ -113,11 +113,6 @@ static inline void set_snan_bit_is_one(bool val, float_status *status) status->snan_bit_is_one = val; } -static inline void set_use_first_nan(bool val, float_status *status) -{ - status->use_first_nan = val; -} - static inline void set_no_signaling_nans(bool val, float_status *status) { status->no_signaling_nans = val; diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index d9f0797eda..84ba4ed20e 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -309,7 +309,6 @@ typedef struct float_status { * softfloat-specialize.inc.c) */ bool snan_bit_is_one; - bool use_first_nan; bool no_signaling_nans; /* should overflowed results subtract re_bias to its exponent? */ bool rebias_overflow; diff --git a/target/xtensa/fpu_helper.c b/target/xtensa/fpu_helper.c index 4b1b021d82..53fc7cfd2a 100644 --- a/target/xtensa/fpu_helper.c +++ b/target/xtensa/fpu_helper.c @@ -59,7 +59,6 @@ static const struct { void xtensa_use_first_nan(CPUXtensaState *env, bool use_first) { - set_use_first_nan(use_first, &env->fp_status); set_float_2nan_prop_rule(use_first ? float_2nan_prop_ab : float_2nan_prop_ba, &env->fp_status); set_float_3nan_prop_rule(use_first ? float_3nan_prop_abc : float_3nan_prop_cba, From 04b6a3e47185135f443d4b98d4910ad26abbcd67 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:30:59 +0000 Subject: [PATCH 32/72] target/m68k: Don't pass NULL float_status to floatx80_default_nan() Currently m68k_cpu_reset_hold() calls floatx80_default_nan(NULL) to get the NaN bit pattern to reset the FPU registers. This works because it happens that our implementation of floatx80_default_nan() doesn't actually look at the float_status pointer except for TARGET_MIPS. However, this isn't guaranteed, and to be able to remove the ifdef in floatx80_default_nan() we're going to need a real float_status here. Rearrange m68k_cpu_reset_hold() so that we initialize env->fp_status earlier, and thus can pass it to floatx80_default_nan(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-28-peter.maydell@linaro.org --- target/m68k/cpu.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/target/m68k/cpu.c b/target/m68k/cpu.c index 5fe335558a..13b76e2248 100644 --- a/target/m68k/cpu.c +++ b/target/m68k/cpu.c @@ -76,7 +76,7 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) CPUState *cs = CPU(obj); M68kCPUClass *mcc = M68K_CPU_GET_CLASS(obj); CPUM68KState *env = cpu_env(cs); - floatx80 nan = floatx80_default_nan(NULL); + floatx80 nan; int i; if (mcc->parent_phases.hold) { @@ -89,10 +89,6 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) #else cpu_m68k_set_sr(env, SR_S | SR_I); #endif - for (i = 0; i < 8; i++) { - env->fregs[i].d = nan; - } - cpu_m68k_set_fpcr(env, 0); /* * M68000 FAMILY PROGRAMMER'S REFERENCE MANUAL * 3.4 FLOATING-POINT INSTRUCTION DETAILS @@ -109,6 +105,12 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) * preceding paragraph for nonsignaling NaNs. */ set_float_2nan_prop_rule(float_2nan_prop_ab, &env->fp_status); + + nan = floatx80_default_nan(&env->fp_status); + for (i = 0; i < 8; i++) { + env->fregs[i].d = nan; + } + cpu_m68k_set_fpcr(env, 0); env->fpsr = 0; /* TODO: We should set PC from the interrupt vector. */ From 3d024e359feff6237ceed5326e08850a70682b3a Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:00 +0000 Subject: [PATCH 33/72] softfloat: Create floatx80 default NaN from parts64_default_nan We create our 128-bit default NaN by calling parts64_default_nan() and then adjusting the result. We can do the same trick for creating the floatx80 default NaN, which lets us drop a target ifdef. floatx80 is used only by: i386 m68k arm nwfpe old floating-point emulation emulation support (which is essentially dead, especially the parts involving floatx80) PPC (only in the xsrqpxp instruction, which just rounds an input value by converting to floatx80 and back, so will never generate the default NaN) The floatx80 default NaN as currently implemented is: m68k: sign = 0, exp = 1...1, int = 1, frac = 1....1 i386: sign = 1, exp = 1...1, int = 1, frac = 10...0 These are the same as the parts64_default_nan for these architectures. This is technically a possible behaviour change for arm linux-user nwfpe emulation emulation, because the default NaN will now have the sign bit clear. But we were already generating a different floatx80 default NaN from the real kernel emulation we are supposedly following, which appears to use an all-bits-1 value: https://elixir.bootlin.com/linux/v6.12/source/arch/arm/nwfpe/softfloat-specialize#L267 This won't affect the only "real" use of the nwfpe emulation, which is ancient binaries that used it as part of the old floating point calling convention; that only uses loads and stores of 32 and 64 bit floats, not any of the floatx80 behaviour the original hardware had. We also get the nwfpe float64 default NaN value wrong: https://elixir.bootlin.com/linux/v6.12/source/arch/arm/nwfpe/softfloat-specialize#L166 so if we ever cared about this obscure corner the right fix would be to correct that so nwfpe used its own default-NaN setting rather than the Arm VFP one. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-29-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 5fbc953e71..9f913ce20a 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -227,17 +227,17 @@ static void parts128_silence_nan(FloatParts128 *p, float_status *status) floatx80 floatx80_default_nan(float_status *status) { floatx80 r; + /* + * Extrapolate from the choices made by parts64_default_nan to fill + * in the floatx80 format. We assume that floatx80's explicit + * integer bit is always set (this is true for i386 and m68k, + * which are the only real users of this format). + */ + FloatParts64 p64; + parts64_default_nan(&p64, status); - /* None of the targets that have snan_bit_is_one use floatx80. */ - assert(!snan_bit_is_one(status)); -#if defined(TARGET_M68K) - r.low = UINT64_C(0xFFFFFFFFFFFFFFFF); - r.high = 0x7FFF; -#else - /* X86 */ - r.low = UINT64_C(0xC000000000000000); - r.high = 0xFFFF; -#endif + r.high = 0x7FFF | (p64.sign << 15); + r.low = (1ULL << DECOMPOSED_BINARY_POINT) | p64.frac; return r; } From a0c4297738880393a1a74d5db551ee7a832e7a91 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:01 +0000 Subject: [PATCH 34/72] target/loongarch: Use normal float_status in fclass_s and fclass_d helpers In target/loongarch's helper_fclass_s() and helper_fclass_d() we pass a zero-initialized float_status struct to float32_is_quiet_nan() and float64_is_quiet_nan(), with the cryptic comment "for snan_bit_is_one". This pattern appears to have been copied from target/riscv, where it is used because the functions there do not have ready access to the CPU state struct. The comment presumably refers to the fact that the main reason the is_quiet_nan() functions want the float_state is because they want to know about the snan_bit_is_one config. In the loongarch helpers, though, we have the CPU state struct to hand. Use the usual env->fp_status here. This avoids our needing to track that we need to update the initializer of the local float_status structs when the core softfloat code adds new options for targets to configure their behaviour. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-30-peter.maydell@linaro.org --- target/loongarch/tcg/fpu_helper.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/target/loongarch/tcg/fpu_helper.c b/target/loongarch/tcg/fpu_helper.c index 37a4859936..aea5e0fe5e 100644 --- a/target/loongarch/tcg/fpu_helper.c +++ b/target/loongarch/tcg/fpu_helper.c @@ -359,8 +359,7 @@ uint64_t helper_fclass_s(CPULoongArchState *env, uint64_t fj) } else if (float32_is_zero_or_denormal(f)) { return sign ? 1 << 4 : 1 << 8; } else if (float32_is_any_nan(f)) { - float_status s = { }; /* for snan_bit_is_one */ - return float32_is_quiet_nan(f, &s) ? 1 << 1 : 1 << 0; + return float32_is_quiet_nan(f, &env->fp_status) ? 1 << 1 : 1 << 0; } else { return sign ? 1 << 3 : 1 << 7; } @@ -378,8 +377,7 @@ uint64_t helper_fclass_d(CPULoongArchState *env, uint64_t fj) } else if (float64_is_zero_or_denormal(f)) { return sign ? 1 << 4 : 1 << 8; } else if (float64_is_any_nan(f)) { - float_status s = { }; /* for snan_bit_is_one */ - return float64_is_quiet_nan(f, &s) ? 1 << 1 : 1 << 0; + return float64_is_quiet_nan(f, &env->fp_status) ? 1 << 1 : 1 << 0; } else { return sign ? 1 << 3 : 1 << 7; } From b1969a5dd4ad72669d739ef6e8caaefb7c7f962c Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:02 +0000 Subject: [PATCH 35/72] target/m68k: In frem helper, initialize local float_status from env->fp_status In the frem helper, we have a local float_status because we want to execute the floatx80_div() with a custom rounding mode. Instead of zero-initializing the local float_status and then having to set it up with the m68k standard behaviour (including the NaN propagation rule and copying the rounding precision from env->fp_status), initialize it as a complete copy of env->fp_status. This will avoid our having to add new code in this function for every new config knob we add to fp_status. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-31-peter.maydell@linaro.org --- target/m68k/fpu_helper.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/target/m68k/fpu_helper.c b/target/m68k/fpu_helper.c index a605162b71..e3f4a18850 100644 --- a/target/m68k/fpu_helper.c +++ b/target/m68k/fpu_helper.c @@ -615,15 +615,13 @@ void HELPER(frem)(CPUM68KState *env, FPReg *res, FPReg *val0, FPReg *val1) fp_rem = floatx80_rem(val1->d, val0->d, &env->fp_status); if (!floatx80_is_any_nan(fp_rem)) { - float_status fp_status = { }; + /* Use local temporary fp_status to set different rounding mode */ + float_status fp_status = env->fp_status; uint32_t quotient; int sign; /* Calculate quotient directly using round to nearest mode */ - set_float_2nan_prop_rule(float_2nan_prop_ab, &fp_status); set_float_rounding_mode(float_round_nearest_even, &fp_status); - set_floatx80_rounding_precision( - get_floatx80_rounding_precision(&env->fp_status), &fp_status); fp_quot.d = floatx80_div(val1->d, val0->d, &fp_status); sign = extractFloatx80Sign(fp_quot.d); From ca81533e94c81838fa05bb8ba7a8a6708e4dca99 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:03 +0000 Subject: [PATCH 36/72] target/m68k: Init local float_status from env fp_status in gdb get/set reg In cf_fpu_gdb_get_reg() and cf_fpu_gdb_set_reg() we do the conversion from float64 to floatx80 using a scratch float_status, because we don't want the conversion to affect the CPU's floating point exception status. Currently we use a zero-initialized float_status. This will get steadily more awkward as we add config knobs to float_status that the target must initialize. Avoid having to add any of that configuration here by instead initializing our local float_status from the env->fp_status. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-32-peter.maydell@linaro.org --- target/m68k/helper.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/target/m68k/helper.c b/target/m68k/helper.c index 9bfc6ae97c..beefeb7069 100644 --- a/target/m68k/helper.c +++ b/target/m68k/helper.c @@ -36,7 +36,8 @@ static int cf_fpu_gdb_get_reg(CPUState *cs, GByteArray *mem_buf, int n) CPUM68KState *env = &cpu->env; if (n < 8) { - float_status s = {}; + /* Use scratch float_status so any exceptions don't change CPU state */ + float_status s = env->fp_status; return gdb_get_reg64(mem_buf, floatx80_to_float64(env->fregs[n].d, &s)); } switch (n) { @@ -56,7 +57,8 @@ static int cf_fpu_gdb_set_reg(CPUState *cs, uint8_t *mem_buf, int n) CPUM68KState *env = &cpu->env; if (n < 8) { - float_status s = {}; + /* Use scratch float_status so any exceptions don't change CPU state */ + float_status s = env->fp_status; env->fregs[n].d = float64_to_floatx80(ldq_be_p(mem_buf), &s); return 8; } From 5edd92d6c340553e1788e86fef844a389f052b72 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:03 +0000 Subject: [PATCH 37/72] target/sparc: Initialize local scratch float_status from env->fp_status In the helper functions flcmps and flcmpd we use a scratch float_status so that we don't change the CPU state if the comparison raises any floating point exception flags. Instead of zero-initializing this scratch float_status, initialize it as a copy of env->fp_status. This avoids the need to explicitly initialize settings like the NaN propagation rule or others we might add to softfloat in future. To do this we need to pass the CPU env pointer in to the helper. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-33-peter.maydell@linaro.org --- target/sparc/fop_helper.c | 8 ++++---- target/sparc/helper.h | 4 ++-- target/sparc/translate.c | 4 ++-- 3 files changed, 8 insertions(+), 8 deletions(-) diff --git a/target/sparc/fop_helper.c b/target/sparc/fop_helper.c index 6f9ccc008a..236d27b19c 100644 --- a/target/sparc/fop_helper.c +++ b/target/sparc/fop_helper.c @@ -490,13 +490,13 @@ uint32_t helper_fcmpeq(CPUSPARCState *env, Int128 src1, Int128 src2) return finish_fcmp(env, r, GETPC()); } -uint32_t helper_flcmps(float32 src1, float32 src2) +uint32_t helper_flcmps(CPUSPARCState *env, float32 src1, float32 src2) { /* * FLCMP never raises an exception nor modifies any FSR fields. * Perform the comparison with a dummy fp environment. */ - float_status discard = { }; + float_status discard = env->fp_status; FloatRelation r; set_float_2nan_prop_rule(float_2nan_prop_s_ba, &discard); @@ -518,9 +518,9 @@ uint32_t helper_flcmps(float32 src1, float32 src2) g_assert_not_reached(); } -uint32_t helper_flcmpd(float64 src1, float64 src2) +uint32_t helper_flcmpd(CPUSPARCState *env, float64 src1, float64 src2) { - float_status discard = { }; + float_status discard = env->fp_status; FloatRelation r; set_float_2nan_prop_rule(float_2nan_prop_s_ba, &discard); diff --git a/target/sparc/helper.h b/target/sparc/helper.h index 134e519a37..1ae3f0c467 100644 --- a/target/sparc/helper.h +++ b/target/sparc/helper.h @@ -51,8 +51,8 @@ DEF_HELPER_FLAGS_3(fcmpd, TCG_CALL_NO_WG, i32, env, f64, f64) DEF_HELPER_FLAGS_3(fcmped, TCG_CALL_NO_WG, i32, env, f64, f64) DEF_HELPER_FLAGS_3(fcmpq, TCG_CALL_NO_WG, i32, env, i128, i128) DEF_HELPER_FLAGS_3(fcmpeq, TCG_CALL_NO_WG, i32, env, i128, i128) -DEF_HELPER_FLAGS_2(flcmps, TCG_CALL_NO_RWG_SE, i32, f32, f32) -DEF_HELPER_FLAGS_2(flcmpd, TCG_CALL_NO_RWG_SE, i32, f64, f64) +DEF_HELPER_FLAGS_3(flcmps, TCG_CALL_NO_RWG_SE, i32, env, f32, f32) +DEF_HELPER_FLAGS_3(flcmpd, TCG_CALL_NO_RWG_SE, i32, env, f64, f64) DEF_HELPER_2(raise_exception, noreturn, env, int) DEF_HELPER_FLAGS_3(faddd, TCG_CALL_NO_WG, f64, env, f64, f64) diff --git a/target/sparc/translate.c b/target/sparc/translate.c index cdd0a95c03..322319a128 100644 --- a/target/sparc/translate.c +++ b/target/sparc/translate.c @@ -5584,7 +5584,7 @@ static bool trans_FLCMPs(DisasContext *dc, arg_FLCMPs *a) src1 = gen_load_fpr_F(dc, a->rs1); src2 = gen_load_fpr_F(dc, a->rs2); - gen_helper_flcmps(cpu_fcc[a->cc], src1, src2); + gen_helper_flcmps(cpu_fcc[a->cc], tcg_env, src1, src2); return advance_pc(dc); } @@ -5601,7 +5601,7 @@ static bool trans_FLCMPd(DisasContext *dc, arg_FLCMPd *a) src1 = gen_load_fpr_D(dc, a->rs1); src2 = gen_load_fpr_D(dc, a->rs2); - gen_helper_flcmpd(cpu_fcc[a->cc], src1, src2); + gen_helper_flcmpd(cpu_fcc[a->cc], tcg_env, src1, src2); return advance_pc(dc); } From 46eb7b92db497ee0d7529ac5356009d8152452c9 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:03 +0000 Subject: [PATCH 38/72] target/ppc: Use env->fp_status in helper_compute_fprf functions In the helper_compute_fprf functions, we pass a dummy float_status in to the is_signaling_nan() function. This is unnecessary, because we have convenient access to the CPU env pointer here and that is already set up with the correct values for the snan_bit_is_one and no_signaling_nans config settings. is_signaling_nan() doesn't ever update the fp_status with any exception flags, so there is no reason not to use env->fp_status here. Use env->fp_status instead of the dummy fp_status. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-34-peter.maydell@linaro.org --- target/ppc/fpu_helper.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/target/ppc/fpu_helper.c b/target/ppc/fpu_helper.c index 230466a87f..d93cfed17b 100644 --- a/target/ppc/fpu_helper.c +++ b/target/ppc/fpu_helper.c @@ -155,8 +155,7 @@ void helper_compute_fprf_##tp(CPUPPCState *env, tp arg) \ } else if (tp##_is_infinity(arg)) { \ fprf = neg ? 0x09 << FPSCR_FPRF : 0x05 << FPSCR_FPRF; \ } else { \ - float_status dummy = { }; /* snan_bit_is_one = 0 */ \ - if (tp##_is_signaling_nan(arg, &dummy)) { \ + if (tp##_is_signaling_nan(arg, &env->fp_status)) { \ fprf = 0x00 << FPSCR_FPRF; \ } else { \ fprf = 0x11 << FPSCR_FPRF; \ From 47aa9001d8c88e75a20559d59f666878b77d1b16 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:03 +0000 Subject: [PATCH 39/72] target/arm: Copy entire float_status in is_ebf MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Now that float_status has a bunch of fp parameters, it is easier to copy an existing structure than create one from scratch. Begin by copying the structure that corresponds to the FPSR and make only the adjustments required for BFloat16 semantics. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Reviewed-by: Peter Maydell Message-id: 20241203203949.483774-2-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- target/arm/tcg/vec_helper.c | 20 +++++++------------- 1 file changed, 7 insertions(+), 13 deletions(-) diff --git a/target/arm/tcg/vec_helper.c b/target/arm/tcg/vec_helper.c index e825d501a2..ad6f26545a 100644 --- a/target/arm/tcg/vec_helper.c +++ b/target/arm/tcg/vec_helper.c @@ -2813,25 +2813,19 @@ bool is_ebf(CPUARMState *env, float_status *statusp, float_status *oddstatusp) * no effect on AArch32 instructions. */ bool ebf = is_a64(env) && env->vfp.fpcr & FPCR_EBF; - *statusp = (float_status){ - .tininess_before_rounding = float_tininess_before_rounding, - .float_rounding_mode = float_round_to_odd_inf, - .flush_to_zero = true, - .flush_inputs_to_zero = true, - .default_nan_mode = true, - }; + + *statusp = env->vfp.fp_status; + set_default_nan_mode(true, statusp); if (ebf) { - float_status *fpst = &env->vfp.fp_status; - set_flush_to_zero(get_flush_to_zero(fpst), statusp); - set_flush_inputs_to_zero(get_flush_inputs_to_zero(fpst), statusp); - set_float_rounding_mode(get_float_rounding_mode(fpst), statusp); - /* EBF=1 needs to do a step with round-to-odd semantics */ *oddstatusp = *statusp; set_float_rounding_mode(float_round_to_odd, oddstatusp); + } else { + set_flush_to_zero(true, statusp); + set_flush_inputs_to_zero(true, statusp); + set_float_rounding_mode(float_round_to_odd_inf, statusp); } - return ebf; } From 1b2de0c3c08afdb27b24d9f03aa3ba7abca432c9 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:04 +0000 Subject: [PATCH 40/72] fpu: Allow runtime choice of default NaN value Currently we hardcode the default NaN value in parts64_default_nan() using a compile-time ifdef ladder. This is awkward for two cases: * for single-QEMU-binary we can't hard-code target-specifics like this * for Arm FEAT_AFP the default NaN value depends on FPCR.AH (specifically the sign bit is different) Add a field to float_status to specify the default NaN value; fall back to the old ifdef behaviour if these are not set. The default NaN value is specified by setting a uint8_t to a pattern corresponding to the sign and upper fraction parts of the NaN; the lower bits of the fraction are set from bit 0 of the pattern. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-35-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 55 ++++++++++++++++++++------------- include/fpu/softfloat-helpers.h | 11 +++++++ include/fpu/softfloat-types.h | 10 ++++++ 3 files changed, 54 insertions(+), 22 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 9f913ce20a..b1ec534983 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -133,35 +133,46 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) { bool sign = 0; uint64_t frac; + uint8_t dnan_pattern = status->default_nan_pattern; + if (dnan_pattern == 0) { #if defined(TARGET_SPARC) || defined(TARGET_M68K) - /* !snan_bit_is_one, set all bits */ - frac = (1ULL << DECOMPOSED_BINARY_POINT) - 1; -#elif defined(TARGET_I386) || defined(TARGET_X86_64) \ + /* Sign bit clear, all frac bits set */ + dnan_pattern = 0b01111111; +#elif defined(TARGET_I386) || defined(TARGET_X86_64) \ || defined(TARGET_MICROBLAZE) - /* !snan_bit_is_one, set sign and msb */ - frac = 1ULL << (DECOMPOSED_BINARY_POINT - 1); - sign = 1; + /* Sign bit set, most significant frac bit set */ + dnan_pattern = 0b11000000; #elif defined(TARGET_HPPA) - /* snan_bit_is_one, set msb-1. */ - frac = 1ULL << (DECOMPOSED_BINARY_POINT - 2); + /* Sign bit clear, msb-1 frac bit set */ + dnan_pattern = 0b00100000; #elif defined(TARGET_HEXAGON) - sign = 1; - frac = ~0ULL; + /* Sign bit set, all frac bits set. */ + dnan_pattern = 0b11111111; #else - /* - * This case is true for Alpha, ARM, MIPS, OpenRISC, PPC, RISC-V, - * S390, SH4, TriCore, and Xtensa. Our other supported targets - * do not have floating-point. - */ - if (snan_bit_is_one(status)) { - /* set all bits other than msb */ - frac = (1ULL << (DECOMPOSED_BINARY_POINT - 1)) - 1; - } else { - /* set msb */ - frac = 1ULL << (DECOMPOSED_BINARY_POINT - 1); - } + /* + * This case is true for Alpha, ARM, MIPS, OpenRISC, PPC, RISC-V, + * S390, SH4, TriCore, and Xtensa. Our other supported targets + * do not have floating-point. + */ + if (snan_bit_is_one(status)) { + /* sign bit clear, set all frac bits other than msb */ + dnan_pattern = 0b00111111; + } else { + /* sign bit clear, set frac msb */ + dnan_pattern = 0b01000000; + } #endif + } + assert(dnan_pattern != 0); + + sign = dnan_pattern >> 7; + /* + * Place default_nan_pattern [6:0] into bits [62:56], + * and replecate bit [0] down into [55:0] + */ + frac = deposit64(0, DECOMPOSED_BINARY_POINT - 7, 7, dnan_pattern); + frac = deposit64(frac, 0, DECOMPOSED_BINARY_POINT - 7, -(dnan_pattern & 1)); *p = (FloatParts64) { .cls = float_class_qnan, diff --git a/include/fpu/softfloat-helpers.h b/include/fpu/softfloat-helpers.h index 10a6763532..dceee23c82 100644 --- a/include/fpu/softfloat-helpers.h +++ b/include/fpu/softfloat-helpers.h @@ -93,6 +93,12 @@ static inline void set_float_infzeronan_rule(FloatInfZeroNaNRule rule, status->float_infzeronan_rule = rule; } +static inline void set_float_default_nan_pattern(uint8_t dnan_pattern, + float_status *status) +{ + status->default_nan_pattern = dnan_pattern; +} + static inline void set_flush_to_zero(bool val, float_status *status) { status->flush_to_zero = val; @@ -154,6 +160,11 @@ static inline FloatInfZeroNaNRule get_float_infzeronan_rule(float_status *status return status->float_infzeronan_rule; } +static inline uint8_t get_float_default_nan_pattern(float_status *status) +{ + return status->default_nan_pattern; +} + static inline bool get_flush_to_zero(float_status *status) { return status->flush_to_zero; diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index 84ba4ed20e..79ca44dcc3 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -303,6 +303,16 @@ typedef struct float_status { /* should denormalised inputs go to zero and set the input_denormal flag? */ bool flush_inputs_to_zero; bool default_nan_mode; + /* + * The pattern to use for the default NaN. Here the high bit specifies + * the default NaN's sign bit, and bits 6..0 specify the high bits of the + * fractional part. The low bits of the fractional part are copies of bit 0. + * The exponent of the default NaN is (as for any NaN) always all 1s. + * Note that a value of 0 here is not a valid NaN. The target must set + * this to the correct non-zero value, or we will assert when trying to + * create a default NaN. + */ + uint8_t default_nan_pattern; /* * The flags below are not used on all specializations and may * constant fold away (see snan_bit_is_one()/no_signalling_nans() in From a264fd5a972afc5950da9135342e2dbc67ba5199 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:04 +0000 Subject: [PATCH 41/72] tests/fp: Set default NaN pattern explicitly Set the default NaN pattern explicitly for the tests/fp code. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-36-peter.maydell@linaro.org --- tests/fp/fp-bench.c | 1 + tests/fp/fp-test-log2.c | 1 + tests/fp/fp-test.c | 1 + 3 files changed, 3 insertions(+) diff --git a/tests/fp/fp-bench.c b/tests/fp/fp-bench.c index 39d80c9038..eacb39b99c 100644 --- a/tests/fp/fp-bench.c +++ b/tests/fp/fp-bench.c @@ -495,6 +495,7 @@ static void run_bench(void) set_float_2nan_prop_rule(float_2nan_prop_s_ab, &soft_status); set_float_3nan_prop_rule(float_3nan_prop_s_cab, &soft_status); set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, &soft_status); + set_float_default_nan_pattern(0b01000000, &soft_status); f = bench_funcs[operation][precision]; g_assert(f); diff --git a/tests/fp/fp-test-log2.c b/tests/fp/fp-test-log2.c index de702c4c80..79f619cdea 100644 --- a/tests/fp/fp-test-log2.c +++ b/tests/fp/fp-test-log2.c @@ -71,6 +71,7 @@ int main(int ac, char **av) int i; set_float_2nan_prop_rule(float_2nan_prop_s_ab, &qsf); + set_float_default_nan_pattern(0b01000000, &qsf); set_float_rounding_mode(float_round_nearest_even, &qsf); test.d = 0.0; diff --git a/tests/fp/fp-test.c b/tests/fp/fp-test.c index f290d523ab..c619e5dbf7 100644 --- a/tests/fp/fp-test.c +++ b/tests/fp/fp-test.c @@ -941,6 +941,7 @@ void run_test(void) */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &qsf); set_float_3nan_prop_rule(float_3nan_prop_s_cab, &qsf); + set_float_default_nan_pattern(0b01000000, &qsf); set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, &qsf); genCases_setLevel(test_level); From 223f4f2e78bd0431d246370e82ae0ac545f0c8d8 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:04 +0000 Subject: [PATCH 42/72] target/microblaze: Set default NaN pattern explicitly Set the default NaN pattern explicitly, and remove the ifdef from parts64_default_nan(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-37-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 3 +-- target/microblaze/cpu.c | 2 ++ 2 files changed, 3 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index b1ec534983..d77404f0c4 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -139,8 +139,7 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) #if defined(TARGET_SPARC) || defined(TARGET_M68K) /* Sign bit clear, all frac bits set */ dnan_pattern = 0b01111111; -#elif defined(TARGET_I386) || defined(TARGET_X86_64) \ - || defined(TARGET_MICROBLAZE) +#elif defined(TARGET_I386) || defined(TARGET_X86_64) /* Sign bit set, most significant frac bit set */ dnan_pattern = 0b11000000; #elif defined(TARGET_HPPA) diff --git a/target/microblaze/cpu.c b/target/microblaze/cpu.c index 710eb1146c..0e1e22d1e8 100644 --- a/target/microblaze/cpu.c +++ b/target/microblaze/cpu.c @@ -207,6 +207,8 @@ static void mb_cpu_reset_hold(Object *obj, ResetType type) * this architecture. */ set_float_2nan_prop_rule(float_2nan_prop_x87, &env->fp_status); + /* Default NaN: sign bit set, most significant frac bit set */ + set_float_default_nan_pattern(0b11000000, &env->fp_status); #if defined(CONFIG_USER_ONLY) /* start in user mode with interrupts enabled. */ From f69da79196ab586a7cacbeecb6809ffa8d8e258c Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:04 +0000 Subject: [PATCH 43/72] target/i386: Set default NaN pattern explicitly Set the default NaN pattern explicitly, and remove the ifdef from parts64_default_nan(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-38-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 3 --- target/i386/tcg/fpu_helper.c | 4 ++++ 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index d77404f0c4..452fe378cd 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -139,9 +139,6 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) #if defined(TARGET_SPARC) || defined(TARGET_M68K) /* Sign bit clear, all frac bits set */ dnan_pattern = 0b01111111; -#elif defined(TARGET_I386) || defined(TARGET_X86_64) - /* Sign bit set, most significant frac bit set */ - dnan_pattern = 0b11000000; #elif defined(TARGET_HPPA) /* Sign bit clear, msb-1 frac bit set */ dnan_pattern = 0b00100000; diff --git a/target/i386/tcg/fpu_helper.c b/target/i386/tcg/fpu_helper.c index 4303b3356a..d0a1e2f3c8 100644 --- a/target/i386/tcg/fpu_helper.c +++ b/target/i386/tcg/fpu_helper.c @@ -181,6 +181,10 @@ void cpu_init_fp_statuses(CPUX86State *env) */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->sse_status); set_float_3nan_prop_rule(float_3nan_prop_abc, &env->sse_status); + /* Default NaN: sign bit set, most significant frac bit set */ + set_float_default_nan_pattern(0b11000000, &env->fp_status); + set_float_default_nan_pattern(0b11000000, &env->mmx_status); + set_float_default_nan_pattern(0b11000000, &env->sse_status); } static inline uint8_t save_exception_flags(CPUX86State *env) From e19d721cb1b3e98659ed9843b3116b13c77f132e Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:05 +0000 Subject: [PATCH 44/72] target/hppa: Set default NaN pattern explicitly Set the default NaN pattern explicitly, and remove the ifdef from parts64_default_nan(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-39-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 3 --- target/hppa/fpu_helper.c | 2 ++ 2 files changed, 2 insertions(+), 3 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 452fe378cd..b5ec1944d1 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -139,9 +139,6 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) #if defined(TARGET_SPARC) || defined(TARGET_M68K) /* Sign bit clear, all frac bits set */ dnan_pattern = 0b01111111; -#elif defined(TARGET_HPPA) - /* Sign bit clear, msb-1 frac bit set */ - dnan_pattern = 0b00100000; #elif defined(TARGET_HEXAGON) /* Sign bit set, all frac bits set. */ dnan_pattern = 0b11111111; diff --git a/target/hppa/fpu_helper.c b/target/hppa/fpu_helper.c index 69c4ce3783..239c027ec5 100644 --- a/target/hppa/fpu_helper.c +++ b/target/hppa/fpu_helper.c @@ -65,6 +65,8 @@ void HELPER(loaded_fr0)(CPUHPPAState *env) set_float_3nan_prop_rule(float_3nan_prop_abc, &env->fp_status); /* For inf * 0 + NaN, return the input NaN */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); + /* Default NaN: sign bit clear, msb-1 frac bit set */ + set_float_default_nan_pattern(0b00100000, &env->fp_status); } void cpu_hppa_loaded_fr0(CPUHPPAState *env) From 369cb9cfe033b43a07e13265598c3df195ce2e4e Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:05 +0000 Subject: [PATCH 45/72] target/alpha: Set default NaN pattern explicitly Set the default NaN pattern explicitly for the alpha target. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-40-peter.maydell@linaro.org --- target/alpha/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/alpha/cpu.c b/target/alpha/cpu.c index 5d75c941f7..70f67e6fd4 100644 --- a/target/alpha/cpu.c +++ b/target/alpha/cpu.c @@ -199,6 +199,8 @@ static void alpha_cpu_initfn(Object *obj) * operand in Fa. That is float_2nan_prop_ba. */ set_float_2nan_prop_rule(float_2nan_prop_x87, &env->fp_status); + /* Default NaN: sign bit clear, msb frac bit set */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); #if defined(CONFIG_USER_ONLY) env->flags = ENV_FLAG_PS_USER | ENV_FLAG_FEN; cpu_alpha_store_fpcr(env, (uint64_t)(FPCR_INVD | FPCR_DZED | FPCR_OVFD From 29fbe4786ecc1613224e64e188c93067ced6e750 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:05 +0000 Subject: [PATCH 46/72] target/arm: Set default NaN pattern explicitly Set the default NaN pattern explicitly for the arm target. This includes setting it for the old linux-user nwfpe emulation. For nwfpe, our default doesn't match the real kernel, but we avoid making a behaviour change in this commit. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-41-peter.maydell@linaro.org --- linux-user/arm/nwfpe/fpa11.c | 5 +++++ target/arm/cpu.c | 2 ++ 2 files changed, 7 insertions(+) diff --git a/linux-user/arm/nwfpe/fpa11.c b/linux-user/arm/nwfpe/fpa11.c index 8356beb52c..0f1afbd91d 100644 --- a/linux-user/arm/nwfpe/fpa11.c +++ b/linux-user/arm/nwfpe/fpa11.c @@ -69,6 +69,11 @@ void resetFPA11(void) * this late date. */ set_float_2nan_prop_rule(float_2nan_prop_s_ab, &fpa11->fp_status); + /* + * Use the same default NaN value as Arm VFP. This doesn't match + * the Linux kernel's nwfpe emulation, which uses an all-1s value. + */ + set_float_default_nan_pattern(0b01000000, &fpa11->fp_status); } void SetRoundingMode(const unsigned int opcode) diff --git a/target/arm/cpu.c b/target/arm/cpu.c index c81f6df3fc..4f7e18eb8e 100644 --- a/target/arm/cpu.c +++ b/target/arm/cpu.c @@ -179,6 +179,7 @@ void arm_register_el_change_hook(ARMCPU *cpu, ARMELChangeHookFn *hook, * the pseudocode function the arguments are in the order c, a, b. * * 0 * Inf + NaN returns the default NaN if the input NaN is quiet, * and the input NaN if it is signalling + * * Default NaN has sign bit clear, msb frac bit set */ static void arm_set_default_fp_behaviours(float_status *s) { @@ -186,6 +187,7 @@ static void arm_set_default_fp_behaviours(float_status *s) set_float_2nan_prop_rule(float_2nan_prop_s_ab, s); set_float_3nan_prop_rule(float_3nan_prop_s_cab, s); set_float_infzeronan_rule(float_infzeronan_dnan_if_qnan, s); + set_float_default_nan_pattern(0b01000000, s); } static void cp_reg_reset(gpointer key, gpointer value, gpointer opaque) From 7d582aa7cc5b834a5bdbdf8a2d2dd053cc4900c0 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:05 +0000 Subject: [PATCH 47/72] target/loongarch: Set default NaN pattern explicitly Set the default NaN pattern explicitly for loongarch. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-42-peter.maydell@linaro.org --- target/loongarch/tcg/fpu_helper.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/loongarch/tcg/fpu_helper.c b/target/loongarch/tcg/fpu_helper.c index aea5e0fe5e..a83acf64b0 100644 --- a/target/loongarch/tcg/fpu_helper.c +++ b/target/loongarch/tcg/fpu_helper.c @@ -38,6 +38,8 @@ void restore_fp_status(CPULoongArchState *env) */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); set_float_3nan_prop_rule(float_3nan_prop_s_cab, &env->fp_status); + /* Default NaN: sign bit clear, msb frac bit set */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); } int ieee_ex_to_loongarch(int xcpt) From 34f73db53d18152d25ae857a92a2f9cf206cbfd9 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:06 +0000 Subject: [PATCH 48/72] target/m68k: Set default NaN pattern explicitly Set the default NaN pattern explicitly for m68k. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-43-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 2 +- target/m68k/cpu.c | 2 ++ 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index b5ec1944d1..ecb7a52ae7 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -136,7 +136,7 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) uint8_t dnan_pattern = status->default_nan_pattern; if (dnan_pattern == 0) { -#if defined(TARGET_SPARC) || defined(TARGET_M68K) +#if defined(TARGET_SPARC) /* Sign bit clear, all frac bits set */ dnan_pattern = 0b01111111; #elif defined(TARGET_HEXAGON) diff --git a/target/m68k/cpu.c b/target/m68k/cpu.c index 13b76e2248..9de8ce6707 100644 --- a/target/m68k/cpu.c +++ b/target/m68k/cpu.c @@ -105,6 +105,8 @@ static void m68k_cpu_reset_hold(Object *obj, ResetType type) * preceding paragraph for nonsignaling NaNs. */ set_float_2nan_prop_rule(float_2nan_prop_ab, &env->fp_status); + /* Default NaN: sign bit clear, all frac bits set */ + set_float_default_nan_pattern(0b01111111, &env->fp_status); nan = floatx80_default_nan(&env->fp_status); for (i = 0; i < 8; i++) { From 5c3ba8105563010f3d4b1c79a90986f03368e534 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:06 +0000 Subject: [PATCH 49/72] target/mips: Set default NaN pattern explicitly Set the default NaN pattern explicitly for MIPS. Note that this is our only target which currently changes the default NaN at runtime (which it was previously doing indirectly when it changed the snan_bit_is_one setting). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-44-peter.maydell@linaro.org --- target/mips/fpu_helper.h | 7 +++++++ target/mips/msa.c | 3 +++ 2 files changed, 10 insertions(+) diff --git a/target/mips/fpu_helper.h b/target/mips/fpu_helper.h index 8ca0ca7ea3..6ad1e466cf 100644 --- a/target/mips/fpu_helper.h +++ b/target/mips/fpu_helper.h @@ -47,6 +47,13 @@ static inline void restore_snan_bit_mode(CPUMIPSState *env) set_float_infzeronan_rule(izn_rule, &env->active_fpu.fp_status); nan3_rule = nan2008 ? float_3nan_prop_s_cab : float_3nan_prop_s_abc; set_float_3nan_prop_rule(nan3_rule, &env->active_fpu.fp_status); + /* + * With nan2008, the default NaN value has the sign bit clear and the + * frac msb set; with the older mode, the sign bit is clear, and all + * frac bits except the msb are set. + */ + set_float_default_nan_pattern(nan2008 ? 0b01000000 : 0b00111111, + &env->active_fpu.fp_status); } diff --git a/target/mips/msa.c b/target/mips/msa.c index 93a9a87d76..fc77bfc7b9 100644 --- a/target/mips/msa.c +++ b/target/mips/msa.c @@ -81,4 +81,7 @@ void msa_reset(CPUMIPSState *env) /* Inf * 0 + NaN returns the input NaN */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->active_tc.msa_fp_status); + /* Default NaN: sign bit clear, frac msb set */ + set_float_default_nan_pattern(0b01000000, + &env->active_tc.msa_fp_status); } From 328dea12ecc6dd44381051013d34c2a2274cfe37 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:06 +0000 Subject: [PATCH 50/72] target/openrisc: Set default NaN pattern explicitly Set the default NaN pattern explicitly for openrisc. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-45-peter.maydell@linaro.org --- target/openrisc/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/openrisc/cpu.c b/target/openrisc/cpu.c index b96561d1f2..3ccf85e95f 100644 --- a/target/openrisc/cpu.c +++ b/target/openrisc/cpu.c @@ -111,6 +111,8 @@ static void openrisc_cpu_reset_hold(Object *obj, ResetType type) */ set_float_2nan_prop_rule(float_2nan_prop_x87, &cpu->env.fp_status); + /* Default NaN: sign bit clear, frac msb set */ + set_float_default_nan_pattern(0b01000000, &cpu->env.fp_status); #ifndef CONFIG_USER_ONLY cpu->env.picmr = 0x00000000; From 236310812c209d641e6a386436934d01d1170ad3 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:06 +0000 Subject: [PATCH 51/72] target/ppc: Set default NaN pattern explicitly Set the default NaN pattern explicitly for ppc. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-46-peter.maydell@linaro.org --- target/ppc/cpu_init.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/target/ppc/cpu_init.c b/target/ppc/cpu_init.c index eb9d7b1370..1253dbf622 100644 --- a/target/ppc/cpu_init.c +++ b/target/ppc/cpu_init.c @@ -7286,6 +7286,10 @@ static void ppc_cpu_reset_hold(Object *obj, ResetType type) set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->vec_status); + /* Default NaN: sign bit clear, set frac msb */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); + set_float_default_nan_pattern(0b01000000, &env->vec_status); + for (i = 0; i < ARRAY_SIZE(env->spr_cb); i++) { ppc_spr_t *spr = &env->spr_cb[i]; From bfff809d711a9d3b2ae290b0a27063fe15ec4591 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:06 +0000 Subject: [PATCH 52/72] target/sh4: Set default NaN pattern explicitly Set the default NaN pattern explicitly for sh4. Note that sh4 is one of the only three targets (the others being HPPA and sometimes MIPS) that has snan_bit_is_one set. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-47-peter.maydell@linaro.org --- target/sh4/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/sh4/cpu.c b/target/sh4/cpu.c index 8f07261dcf..d5008859b8 100644 --- a/target/sh4/cpu.c +++ b/target/sh4/cpu.c @@ -127,6 +127,8 @@ static void superh_cpu_reset_hold(Object *obj, ResetType type) set_flush_to_zero(1, &env->fp_status); #endif set_default_nan_mode(1, &env->fp_status); + /* sign bit clear, set all frac bits other than msb */ + set_float_default_nan_pattern(0b00111111, &env->fp_status); } static void superh_cpu_disas_set_info(CPUState *cpu, disassemble_info *info) From 031af9cd9bc750a9d2f7c96535f87c86ffe80a0d Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 53/72] target/rx: Set default NaN pattern explicitly Set the default NaN pattern explicitly for rx. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-48-peter.maydell@linaro.org --- target/rx/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/rx/cpu.c b/target/rx/cpu.c index 65a74ce720..69ec0bc7b3 100644 --- a/target/rx/cpu.c +++ b/target/rx/cpu.c @@ -100,6 +100,8 @@ static void rx_cpu_reset_hold(Object *obj, ResetType type) * then prefer dest over source", which is float_2nan_prop_s_ab. */ set_float_2nan_prop_rule(float_2nan_prop_x87, &env->fp_status); + /* Default NaN value: sign bit clear, set frac msb */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); } static ObjectClass *rx_cpu_class_by_name(const char *cpu_model) From 5ab49c3a0991447d2f5b32e2b453ed111e4c968f Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 54/72] target/s390x: Set default NaN pattern explicitly Set the default NaN pattern explicitly for s390x. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-49-peter.maydell@linaro.org --- target/s390x/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c index e74055bad7..adb27504ad 100644 --- a/target/s390x/cpu.c +++ b/target/s390x/cpu.c @@ -209,6 +209,8 @@ static void s390_cpu_reset_hold(Object *obj, ResetType type) set_float_3nan_prop_rule(float_3nan_prop_s_abc, &env->fpu_status); set_float_infzeronan_rule(float_infzeronan_dnan_always, &env->fpu_status); + /* Default NaN value: sign bit clear, frac msb set */ + set_float_default_nan_pattern(0b01000000, &env->fpu_status); /* fall through */ case RESET_TYPE_S390_CPU_NORMAL: env->psw.mask &= ~PSW_MASK_RI; From 45fb2cd61eee6d7f500eb96dba73023cf0057b40 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 55/72] target/sparc: Set default NaN pattern explicitly Set the default NaN pattern explicitly for SPARC, and remove the ifdef from parts64_default_nan. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-50-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 5 +---- target/sparc/cpu.c | 2 ++ 2 files changed, 3 insertions(+), 4 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index ecb7a52ae7..06185237d0 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -136,10 +136,7 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) uint8_t dnan_pattern = status->default_nan_pattern; if (dnan_pattern == 0) { -#if defined(TARGET_SPARC) - /* Sign bit clear, all frac bits set */ - dnan_pattern = 0b01111111; -#elif defined(TARGET_HEXAGON) +#if defined(TARGET_HEXAGON) /* Sign bit set, all frac bits set. */ dnan_pattern = 0b11111111; #else diff --git a/target/sparc/cpu.c b/target/sparc/cpu.c index 0f2997a85e..6b66ecb3f5 100644 --- a/target/sparc/cpu.c +++ b/target/sparc/cpu.c @@ -818,6 +818,8 @@ static void sparc_cpu_realizefn(DeviceState *dev, Error **errp) set_float_3nan_prop_rule(float_3nan_prop_s_cba, &env->fp_status); /* For inf * 0 + NaN, return the input NaN */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); + /* Default NaN value: sign bit clear, all frac bits set */ + set_float_default_nan_pattern(0b01111111, &env->fp_status); cpu_exec_realizefn(cs, &local_err); if (local_err != NULL) { From b9aa1e5658dacca25b2970bba6f3bf79351ca46c Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 56/72] target/xtensa: Set default NaN pattern explicitly Set the default NaN pattern explicitly for xtensa. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-51-peter.maydell@linaro.org --- target/xtensa/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/xtensa/cpu.c b/target/xtensa/cpu.c index 3163b75823..0d4d79b58b 100644 --- a/target/xtensa/cpu.c +++ b/target/xtensa/cpu.c @@ -136,6 +136,8 @@ static void xtensa_cpu_reset_hold(Object *obj, ResetType type) /* For inf * 0 + NaN, return the input NaN */ set_float_infzeronan_rule(float_infzeronan_dnan_never, &env->fp_status); set_no_signaling_nans(!dfpu, &env->fp_status); + /* Default NaN value: sign bit clear, set frac msb */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); xtensa_use_first_nan(env, !dfpu); } From 38ea9ade29e1e3208dc0e82708388c0a1d73ebf2 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 57/72] target/hexagon: Set default NaN pattern explicitly Set the default NaN pattern explicitly for hexagon. Remove the ifdef from parts64_default_nan(); the only remaining unconverted targets all use the default case. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-52-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 5 ----- target/hexagon/cpu.c | 2 ++ 2 files changed, 2 insertions(+), 5 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 06185237d0..5954a6213b 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -136,10 +136,6 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) uint8_t dnan_pattern = status->default_nan_pattern; if (dnan_pattern == 0) { -#if defined(TARGET_HEXAGON) - /* Sign bit set, all frac bits set. */ - dnan_pattern = 0b11111111; -#else /* * This case is true for Alpha, ARM, MIPS, OpenRISC, PPC, RISC-V, * S390, SH4, TriCore, and Xtensa. Our other supported targets @@ -152,7 +148,6 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) /* sign bit clear, set frac msb */ dnan_pattern = 0b01000000; } -#endif } assert(dnan_pattern != 0); diff --git a/target/hexagon/cpu.c b/target/hexagon/cpu.c index 020038fc49..c9aa9408ec 100644 --- a/target/hexagon/cpu.c +++ b/target/hexagon/cpu.c @@ -286,6 +286,8 @@ static void hexagon_cpu_reset_hold(Object *obj, ResetType type) set_default_nan_mode(1, &env->fp_status); set_float_detect_tininess(float_tininess_before_rounding, &env->fp_status); + /* Default NaN value: sign bit set, all frac bits set */ + set_float_default_nan_pattern(0b11111111, &env->fp_status); } static void hexagon_cpu_disas_set_info(CPUState *s, disassemble_info *info) From 3d3d399e76c204c718f3ec6ef48fd0bb303070ab Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 58/72] target/riscv: Set default NaN pattern explicitly Set the default NaN pattern explicitly for riscv. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-53-peter.maydell@linaro.org --- target/riscv/cpu.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index f219f0c3b5..80b09952e7 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -1022,6 +1022,8 @@ static void riscv_cpu_reset_hold(Object *obj, ResetType type) cs->exception_index = RISCV_EXCP_NONE; env->load_res = -1; set_default_nan_mode(1, &env->fp_status); + /* Default NaN value: sign bit clear, frac msb set */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); env->vill = true; #ifndef CONFIG_USER_ONLY From d921f8fd56f144557413f8e3e35e4c12064e4091 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:07 +0000 Subject: [PATCH 59/72] target/tricore: Set default NaN pattern explicitly Set the default NaN pattern explicitly for tricore. Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-54-peter.maydell@linaro.org --- target/tricore/helper.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/target/tricore/helper.c b/target/tricore/helper.c index 7014255f77..e8b0ec5161 100644 --- a/target/tricore/helper.c +++ b/target/tricore/helper.c @@ -117,6 +117,8 @@ void fpu_set_state(CPUTriCoreState *env) set_flush_to_zero(1, &env->fp_status); set_float_detect_tininess(float_tininess_before_rounding, &env->fp_status); set_default_nan_mode(1, &env->fp_status); + /* Default NaN pattern: sign bit clear, frac msb set */ + set_float_default_nan_pattern(0b01000000, &env->fp_status); } uint32_t psw_read(CPUTriCoreState *env) From 86bb2f44cd6f4a45132beffcdacdf3b43d836042 Mon Sep 17 00:00:00 2001 From: Peter Maydell Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 60/72] fpu: Remove default handling for dnan_pattern Now that all our targets have bene converted to explicitly specify their pattern for the default NaN value we can remove the remaining fallback code in parts64_default_nan(). Signed-off-by: Peter Maydell Reviewed-by: Richard Henderson Message-id: 20241202131347.498124-55-peter.maydell@linaro.org --- fpu/softfloat-specialize.c.inc | 14 -------------- 1 file changed, 14 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index 5954a6213b..e075c47889 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -135,20 +135,6 @@ static void parts64_default_nan(FloatParts64 *p, float_status *status) uint64_t frac; uint8_t dnan_pattern = status->default_nan_pattern; - if (dnan_pattern == 0) { - /* - * This case is true for Alpha, ARM, MIPS, OpenRISC, PPC, RISC-V, - * S390, SH4, TriCore, and Xtensa. Our other supported targets - * do not have floating-point. - */ - if (snan_bit_is_one(status)) { - /* sign bit clear, set all frac bits other than msb */ - dnan_pattern = 0b00111111; - } else { - /* sign bit clear, set frac msb */ - dnan_pattern = 0b01000000; - } - } assert(dnan_pattern != 0); sign = dnan_pattern >> 7; From f73bd7503def86ab322a8df560b00ef67e08ce6e Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 61/72] softfloat: Inline pickNaNMulAdd MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Inline pickNaNMulAdd into its only caller. This makes one assert redundant with the immediately preceding IF. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-id: 20241203203949.483774-3-richard.henderson@linaro.org [PMM: keep comment from old code in new location] Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 41 +++++++++++++++++++++++++- fpu/softfloat-specialize.c.inc | 54 ---------------------------------- 2 files changed, 40 insertions(+), 55 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 655b7d9da5..c1a97c35b2 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -79,9 +79,48 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, } if (s->default_nan_mode) { + /* + * We guarantee not to require the target to tell us how to + * pick a NaN if we're always returning the default NaN. + * But if we're not in default-NaN mode then the target must + * specify. + */ which = 3; + } else if (infzero) { + /* + * Inf * 0 + NaN -- some implementations return the + * default NaN here, and some return the input NaN. + */ + switch (s->float_infzeronan_rule) { + case float_infzeronan_dnan_never: + which = 2; + break; + case float_infzeronan_dnan_always: + which = 3; + break; + case float_infzeronan_dnan_if_qnan: + which = is_qnan(c->cls) ? 3 : 2; + break; + default: + g_assert_not_reached(); + } } else { - which = pickNaNMulAdd(a->cls, b->cls, c->cls, infzero, have_snan, s); + FloatClass cls[3] = { a->cls, b->cls, c->cls }; + Float3NaNPropRule rule = s->float_3nan_prop_rule; + + assert(rule != float_3nan_prop_none); + if (have_snan && (rule & R_3NAN_SNAN_MASK)) { + /* We have at least one SNaN input and should prefer it */ + do { + which = rule & R_3NAN_1ST_MASK; + rule >>= R_3NAN_1ST_LENGTH; + } while (!is_snan(cls[which])); + } else { + do { + which = rule & R_3NAN_1ST_MASK; + rule >>= R_3NAN_1ST_LENGTH; + } while (!is_nan(cls[which])); + } } if (which == 3) { diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index e075c47889..f26458eaa3 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -448,60 +448,6 @@ static int pickNaN(FloatClass a_cls, FloatClass b_cls, } } -/*---------------------------------------------------------------------------- -| Select which NaN to propagate for a three-input operation. -| For the moment we assume that no CPU needs the 'larger significand' -| information. -| Return values : 0 : a; 1 : b; 2 : c; 3 : default-NaN -*----------------------------------------------------------------------------*/ -static int pickNaNMulAdd(FloatClass a_cls, FloatClass b_cls, FloatClass c_cls, - bool infzero, bool have_snan, float_status *status) -{ - FloatClass cls[3] = { a_cls, b_cls, c_cls }; - Float3NaNPropRule rule = status->float_3nan_prop_rule; - int which; - - /* - * We guarantee not to require the target to tell us how to - * pick a NaN if we're always returning the default NaN. - * But if we're not in default-NaN mode then the target must - * specify. - */ - assert(!status->default_nan_mode); - - if (infzero) { - /* - * Inf * 0 + NaN -- some implementations return the default NaN here, - * and some return the input NaN. - */ - switch (status->float_infzeronan_rule) { - case float_infzeronan_dnan_never: - return 2; - case float_infzeronan_dnan_always: - return 3; - case float_infzeronan_dnan_if_qnan: - return is_qnan(c_cls) ? 3 : 2; - default: - g_assert_not_reached(); - } - } - - assert(rule != float_3nan_prop_none); - if (have_snan && (rule & R_3NAN_SNAN_MASK)) { - /* We have at least one SNaN input and should prefer it */ - do { - which = rule & R_3NAN_1ST_MASK; - rule >>= R_3NAN_1ST_LENGTH; - } while (!is_snan(cls[which])); - } else { - do { - which = rule & R_3NAN_1ST_MASK; - rule >>= R_3NAN_1ST_LENGTH; - } while (!is_nan(cls[which])); - } - return which; -} - /*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. From e00286187630b81fb3360d560ff7a6ca90f7191f Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 62/72] softfloat: Use goto for default nan case in pick_nan_muladd MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Remove "3" as a special case for which and simply branch to return the desired value. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-id: 20241203203949.483774-4-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index c1a97c35b2..be7e93127d 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -85,7 +85,7 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, * But if we're not in default-NaN mode then the target must * specify. */ - which = 3; + goto default_nan; } else if (infzero) { /* * Inf * 0 + NaN -- some implementations return the @@ -93,17 +93,18 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, */ switch (s->float_infzeronan_rule) { case float_infzeronan_dnan_never: - which = 2; break; case float_infzeronan_dnan_always: - which = 3; - break; + goto default_nan; case float_infzeronan_dnan_if_qnan: - which = is_qnan(c->cls) ? 3 : 2; + if (is_qnan(c->cls)) { + goto default_nan; + } break; default: g_assert_not_reached(); } + which = 2; } else { FloatClass cls[3] = { a->cls, b->cls, c->cls }; Float3NaNPropRule rule = s->float_3nan_prop_rule; @@ -123,11 +124,6 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, } } - if (which == 3) { - parts_default_nan(a, s); - return a; - } - switch (which) { case 0: break; @@ -144,6 +140,10 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, parts_silence_nan(a, s); } return a; + + default_nan: + parts_default_nan(a, s); + return a; } /* From 229416c67e8faed47dfa1d26777e71df2cc3b320 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 63/72] softfloat: Remove which from parts_pick_nan_muladd MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Assign the pointer return value to 'a' directly, rather than going through an intermediary index. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-id: 20241203203949.483774-5-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 32 ++++++++++---------------------- 1 file changed, 10 insertions(+), 22 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index be7e93127d..525db61741 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -65,9 +65,9 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, FloatPartsN *c, float_status *s, int ab_mask, int abc_mask) { - int which; bool infzero = (ab_mask == float_cmask_infzero); bool have_snan = (abc_mask & float_cmask_snan); + FloatPartsN *ret; if (unlikely(have_snan)) { float_raise(float_flag_invalid | float_flag_invalid_snan, s); @@ -104,42 +104,30 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, default: g_assert_not_reached(); } - which = 2; + ret = c; } else { - FloatClass cls[3] = { a->cls, b->cls, c->cls }; + FloatPartsN *val[3] = { a, b, c }; Float3NaNPropRule rule = s->float_3nan_prop_rule; assert(rule != float_3nan_prop_none); if (have_snan && (rule & R_3NAN_SNAN_MASK)) { /* We have at least one SNaN input and should prefer it */ do { - which = rule & R_3NAN_1ST_MASK; + ret = val[rule & R_3NAN_1ST_MASK]; rule >>= R_3NAN_1ST_LENGTH; - } while (!is_snan(cls[which])); + } while (!is_snan(ret->cls)); } else { do { - which = rule & R_3NAN_1ST_MASK; + ret = val[rule & R_3NAN_1ST_MASK]; rule >>= R_3NAN_1ST_LENGTH; - } while (!is_nan(cls[which])); + } while (!is_nan(ret->cls)); } } - switch (which) { - case 0: - break; - case 1: - a = b; - break; - case 2: - a = c; - break; - default: - g_assert_not_reached(); + if (is_snan(ret->cls)) { + parts_silence_nan(ret, s); } - if (is_snan(a->cls)) { - parts_silence_nan(a, s); - } - return a; + return ret; default_nan: parts_default_nan(a, s); From 8704c753e8fe3155e22244f2c23e253a73aa4565 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 64/72] softfloat: Pad array size in pick_nan_muladd MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit While all indices into val[] should be in [0-2], the mask applied is two bits. To help static analysis see there is no possibility of read beyond the end of the array, pad the array to 4 entries, with the final being (implicitly) NULL. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-id: 20241203203949.483774-6-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 525db61741..5fcdbc87fd 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -106,7 +106,7 @@ static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, } ret = c; } else { - FloatPartsN *val[3] = { a, b, c }; + FloatPartsN *val[R_3NAN_1ST_MASK + 1] = { a, b, c }; Float3NaNPropRule rule = s->float_3nan_prop_rule; assert(rule != float_3nan_prop_none); From 313938c105946dacfc886217b47310adb01194c3 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 65/72] softfloat: Move propagateFloatx80NaN to softfloat.c This function is part of the public interface and is not "specialized" to any target in any way. Signed-off-by: Richard Henderson Reviewed-by: Peter Maydell Message-id: 20241203203949.483774-7-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-specialize.c.inc | 52 ---------------------------------- fpu/softfloat.c | 52 ++++++++++++++++++++++++++++++++++ 2 files changed, 52 insertions(+), 52 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index f26458eaa3..f7a320f6ff 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -551,58 +551,6 @@ floatx80 floatx80_silence_nan(floatx80 a, float_status *status) return a; } -/*---------------------------------------------------------------------------- -| Takes two extended double-precision floating-point values `a' and `b', one -| of which is a NaN, and returns the appropriate NaN result. If either `a' or -| `b' is a signaling NaN, the invalid exception is raised. -*----------------------------------------------------------------------------*/ - -floatx80 propagateFloatx80NaN(floatx80 a, floatx80 b, float_status *status) -{ - bool aIsLargerSignificand; - FloatClass a_cls, b_cls; - - /* This is not complete, but is good enough for pickNaN. */ - a_cls = (!floatx80_is_any_nan(a) - ? float_class_normal - : floatx80_is_signaling_nan(a, status) - ? float_class_snan - : float_class_qnan); - b_cls = (!floatx80_is_any_nan(b) - ? float_class_normal - : floatx80_is_signaling_nan(b, status) - ? float_class_snan - : float_class_qnan); - - if (is_snan(a_cls) || is_snan(b_cls)) { - float_raise(float_flag_invalid, status); - } - - if (status->default_nan_mode) { - return floatx80_default_nan(status); - } - - if (a.low < b.low) { - aIsLargerSignificand = 0; - } else if (b.low < a.low) { - aIsLargerSignificand = 1; - } else { - aIsLargerSignificand = (a.high < b.high) ? 1 : 0; - } - - if (pickNaN(a_cls, b_cls, aIsLargerSignificand, status)) { - if (is_snan(b_cls)) { - return floatx80_silence_nan(b, status); - } - return b; - } else { - if (is_snan(a_cls)) { - return floatx80_silence_nan(a, status); - } - return a; - } -} - /*---------------------------------------------------------------------------- | Returns 1 if the quadruple-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 027a8e576d..6ba1cfd32a 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -4920,6 +4920,58 @@ void normalizeFloatx80Subnormal(uint64_t aSig, int32_t *zExpPtr, *zExpPtr = 1 - shiftCount; } +/*---------------------------------------------------------------------------- +| Takes two extended double-precision floating-point values `a' and `b', one +| of which is a NaN, and returns the appropriate NaN result. If either `a' or +| `b' is a signaling NaN, the invalid exception is raised. +*----------------------------------------------------------------------------*/ + +floatx80 propagateFloatx80NaN(floatx80 a, floatx80 b, float_status *status) +{ + bool aIsLargerSignificand; + FloatClass a_cls, b_cls; + + /* This is not complete, but is good enough for pickNaN. */ + a_cls = (!floatx80_is_any_nan(a) + ? float_class_normal + : floatx80_is_signaling_nan(a, status) + ? float_class_snan + : float_class_qnan); + b_cls = (!floatx80_is_any_nan(b) + ? float_class_normal + : floatx80_is_signaling_nan(b, status) + ? float_class_snan + : float_class_qnan); + + if (is_snan(a_cls) || is_snan(b_cls)) { + float_raise(float_flag_invalid, status); + } + + if (status->default_nan_mode) { + return floatx80_default_nan(status); + } + + if (a.low < b.low) { + aIsLargerSignificand = 0; + } else if (b.low < a.low) { + aIsLargerSignificand = 1; + } else { + aIsLargerSignificand = (a.high < b.high) ? 1 : 0; + } + + if (pickNaN(a_cls, b_cls, aIsLargerSignificand, status)) { + if (is_snan(b_cls)) { + return floatx80_silence_nan(b, status); + } + return b; + } else { + if (is_snan(a_cls)) { + return floatx80_silence_nan(a, status); + } + return a; + } +} + /*---------------------------------------------------------------------------- | Takes an abstract floating-point value having sign `zSign', exponent `zExp', | and extended significand formed by the concatenation of `zSig0' and `zSig1', From 1b34f934ddefc3bdc4322694c2726ddc4d9ebd45 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 66/72] softfloat: Use parts_pick_nan in propagateFloatx80NaN Unpacking and repacking the parts may be slightly more work than we did before, but we get to reuse more code. For a code path handling exceptional values, this is an improvement. Signed-off-by: Richard Henderson Message-id: 20241203203949.483774-8-richard.henderson@linaro.org Signed-off-by: Peter Maydell Reviewed-by: Peter Maydell --- fpu/softfloat.c | 43 +++++-------------------------------------- 1 file changed, 5 insertions(+), 38 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 6ba1cfd32a..8de8d5f342 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -4928,48 +4928,15 @@ void normalizeFloatx80Subnormal(uint64_t aSig, int32_t *zExpPtr, floatx80 propagateFloatx80NaN(floatx80 a, floatx80 b, float_status *status) { - bool aIsLargerSignificand; - FloatClass a_cls, b_cls; + FloatParts128 pa, pb, *pr; - /* This is not complete, but is good enough for pickNaN. */ - a_cls = (!floatx80_is_any_nan(a) - ? float_class_normal - : floatx80_is_signaling_nan(a, status) - ? float_class_snan - : float_class_qnan); - b_cls = (!floatx80_is_any_nan(b) - ? float_class_normal - : floatx80_is_signaling_nan(b, status) - ? float_class_snan - : float_class_qnan); - - if (is_snan(a_cls) || is_snan(b_cls)) { - float_raise(float_flag_invalid, status); - } - - if (status->default_nan_mode) { + if (!floatx80_unpack_canonical(&pa, a, status) || + !floatx80_unpack_canonical(&pb, b, status)) { return floatx80_default_nan(status); } - if (a.low < b.low) { - aIsLargerSignificand = 0; - } else if (b.low < a.low) { - aIsLargerSignificand = 1; - } else { - aIsLargerSignificand = (a.high < b.high) ? 1 : 0; - } - - if (pickNaN(a_cls, b_cls, aIsLargerSignificand, status)) { - if (is_snan(b_cls)) { - return floatx80_silence_nan(b, status); - } - return b; - } else { - if (is_snan(a_cls)) { - return floatx80_silence_nan(a, status); - } - return a; - } + pr = parts_pick_nan(&pa, &pb, status); + return floatx80_round_pack_canonical(pr, status); } /*---------------------------------------------------------------------------- From 04cbb4acc60c98c4080df6d03a09bbca0e408f67 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:08 +0000 Subject: [PATCH 67/72] softfloat: Inline pickNaN MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Inline pickNaN into its only caller. This makes one assert redundant with the immediately preceding IF. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-id: 20241203203949.483774-9-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 82 +++++++++++++++++++++++++---- fpu/softfloat-specialize.c.inc | 96 ---------------------------------- 2 files changed, 73 insertions(+), 105 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 5fcdbc87fd..a1b148e90b 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -39,24 +39,88 @@ static void partsN(return_nan)(FloatPartsN *a, float_status *s) static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, float_status *s) { + int cmp, which; + if (is_snan(a->cls) || is_snan(b->cls)) { float_raise(float_flag_invalid | float_flag_invalid_snan, s); } if (s->default_nan_mode) { parts_default_nan(a, s); - } else { - int cmp = frac_cmp(a, b); - if (cmp == 0) { - cmp = a->sign < b->sign; - } + return a; + } - if (pickNaN(a->cls, b->cls, cmp > 0, s)) { - a = b; - } + cmp = frac_cmp(a, b); + if (cmp == 0) { + cmp = a->sign < b->sign; + } + + switch (s->float_2nan_prop_rule) { + case float_2nan_prop_s_ab: if (is_snan(a->cls)) { - parts_silence_nan(a, s); + which = 0; + } else if (is_snan(b->cls)) { + which = 1; + } else if (is_qnan(a->cls)) { + which = 0; + } else { + which = 1; } + break; + case float_2nan_prop_s_ba: + if (is_snan(b->cls)) { + which = 1; + } else if (is_snan(a->cls)) { + which = 0; + } else if (is_qnan(b->cls)) { + which = 1; + } else { + which = 0; + } + break; + case float_2nan_prop_ab: + which = is_nan(a->cls) ? 0 : 1; + break; + case float_2nan_prop_ba: + which = is_nan(b->cls) ? 1 : 0; + break; + case float_2nan_prop_x87: + /* + * This implements x87 NaN propagation rules: + * SNaN + QNaN => return the QNaN + * two SNaNs => return the one with the larger significand, silenced + * two QNaNs => return the one with the larger significand + * SNaN and a non-NaN => return the SNaN, silenced + * QNaN and a non-NaN => return the QNaN + * + * If we get down to comparing significands and they are the same, + * return the NaN with the positive sign bit (if any). + */ + if (is_snan(a->cls)) { + if (is_snan(b->cls)) { + which = cmp > 0 ? 0 : 1; + } else { + which = is_qnan(b->cls) ? 1 : 0; + } + } else if (is_qnan(a->cls)) { + if (is_snan(b->cls) || !is_qnan(b->cls)) { + which = 0; + } else { + which = cmp > 0 ? 0 : 1; + } + } else { + which = 1; + } + break; + default: + g_assert_not_reached(); + } + + if (which) { + a = b; + } + if (is_snan(a->cls)) { + parts_silence_nan(a, s); } return a; } diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index f7a320f6ff..cbbbab52ba 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -352,102 +352,6 @@ bool float32_is_signaling_nan(float32 a_, float_status *status) } } -/*---------------------------------------------------------------------------- -| Select which NaN to propagate for a two-input operation. -| IEEE754 doesn't specify all the details of this, so the -| algorithm is target-specific. -| The routine is passed various bits of information about the -| two NaNs and should return 0 to select NaN a and 1 for NaN b. -| Note that signalling NaNs are always squashed to quiet NaNs -| by the caller, by calling floatXX_silence_nan() before -| returning them. -| -| aIsLargerSignificand is only valid if both a and b are NaNs -| of some kind, and is true if a has the larger significand, -| or if both a and b have the same significand but a is -| positive but b is negative. It is only needed for the x87 -| tie-break rule. -*----------------------------------------------------------------------------*/ - -static int pickNaN(FloatClass a_cls, FloatClass b_cls, - bool aIsLargerSignificand, float_status *status) -{ - /* - * We guarantee not to require the target to tell us how to - * pick a NaN if we're always returning the default NaN. - * But if we're not in default-NaN mode then the target must - * specify via set_float_2nan_prop_rule(). - */ - assert(!status->default_nan_mode); - - switch (status->float_2nan_prop_rule) { - case float_2nan_prop_s_ab: - if (is_snan(a_cls)) { - return 0; - } else if (is_snan(b_cls)) { - return 1; - } else if (is_qnan(a_cls)) { - return 0; - } else { - return 1; - } - break; - case float_2nan_prop_s_ba: - if (is_snan(b_cls)) { - return 1; - } else if (is_snan(a_cls)) { - return 0; - } else if (is_qnan(b_cls)) { - return 1; - } else { - return 0; - } - break; - case float_2nan_prop_ab: - if (is_nan(a_cls)) { - return 0; - } else { - return 1; - } - break; - case float_2nan_prop_ba: - if (is_nan(b_cls)) { - return 1; - } else { - return 0; - } - break; - case float_2nan_prop_x87: - /* - * This implements x87 NaN propagation rules: - * SNaN + QNaN => return the QNaN - * two SNaNs => return the one with the larger significand, silenced - * two QNaNs => return the one with the larger significand - * SNaN and a non-NaN => return the SNaN, silenced - * QNaN and a non-NaN => return the QNaN - * - * If we get down to comparing significands and they are the same, - * return the NaN with the positive sign bit (if any). - */ - if (is_snan(a_cls)) { - if (is_snan(b_cls)) { - return aIsLargerSignificand ? 0 : 1; - } - return is_qnan(b_cls) ? 1 : 0; - } else if (is_qnan(a_cls)) { - if (is_snan(b_cls) || !is_qnan(b_cls)) { - return 0; - } else { - return aIsLargerSignificand ? 0 : 1; - } - } else { - return 1; - } - default: - g_assert_not_reached(); - } -} - /*---------------------------------------------------------------------------- | Returns 1 if the double-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. From 2da7553f2ee818e98e69136ab02106f3bccddf68 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:09 +0000 Subject: [PATCH 68/72] softfloat: Share code between parts_pick_nan cases Remember if there was an SNaN, and use that to simplify float_2nan_prop_s_{ab,ba} to only the snan component. Then, fall through to the corresponding float_2nan_prop_{ab,ba} case to handle any remaining nans, which must be quiet. Signed-off-by: Richard Henderson Reviewed-by: Peter Maydell Message-id: 20241203203949.483774-10-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 32 ++++++++++++-------------------- 1 file changed, 12 insertions(+), 20 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index a1b148e90b..3c77dcbb15 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -39,10 +39,12 @@ static void partsN(return_nan)(FloatPartsN *a, float_status *s) static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, float_status *s) { + bool have_snan = false; int cmp, which; if (is_snan(a->cls) || is_snan(b->cls)) { float_raise(float_flag_invalid | float_flag_invalid_snan, s); + have_snan = true; } if (s->default_nan_mode) { @@ -57,30 +59,20 @@ static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, switch (s->float_2nan_prop_rule) { case float_2nan_prop_s_ab: - if (is_snan(a->cls)) { - which = 0; - } else if (is_snan(b->cls)) { - which = 1; - } else if (is_qnan(a->cls)) { - which = 0; - } else { - which = 1; + if (have_snan) { + which = is_snan(a->cls) ? 0 : 1; + break; } - break; - case float_2nan_prop_s_ba: - if (is_snan(b->cls)) { - which = 1; - } else if (is_snan(a->cls)) { - which = 0; - } else if (is_qnan(b->cls)) { - which = 1; - } else { - which = 0; - } - break; + /* fall through */ case float_2nan_prop_ab: which = is_nan(a->cls) ? 0 : 1; break; + case float_2nan_prop_s_ba: + if (have_snan) { + which = is_snan(b->cls) ? 1 : 0; + break; + } + /* fall through */ case float_2nan_prop_ba: which = is_nan(b->cls) ? 1 : 0; break; From 9778115ed780c8d8b027dea4125afb3890511797 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:09 +0000 Subject: [PATCH 69/72] softfloat: Sink frac_cmp in parts_pick_nan until needed Move the fractional comparison to the end of the float_2nan_prop_x87 case. This is not required for any other 2nan propagation rule. Reorganize the x87 case itself to break out of the switch when the fractional comparison is not required. Signed-off-by: Richard Henderson Reviewed-by: Peter Maydell Message-id: 20241203203949.483774-11-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 19 +++++++++---------- 1 file changed, 9 insertions(+), 10 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index 3c77dcbb15..abe24aeaa0 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -52,11 +52,6 @@ static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, return a; } - cmp = frac_cmp(a, b); - if (cmp == 0) { - cmp = a->sign < b->sign; - } - switch (s->float_2nan_prop_rule) { case float_2nan_prop_s_ab: if (have_snan) { @@ -89,20 +84,24 @@ static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, * return the NaN with the positive sign bit (if any). */ if (is_snan(a->cls)) { - if (is_snan(b->cls)) { - which = cmp > 0 ? 0 : 1; - } else { + if (!is_snan(b->cls)) { which = is_qnan(b->cls) ? 1 : 0; + break; } } else if (is_qnan(a->cls)) { if (is_snan(b->cls) || !is_qnan(b->cls)) { which = 0; - } else { - which = cmp > 0 ? 0 : 1; + break; } } else { which = 1; + break; } + cmp = frac_cmp(a, b); + if (cmp == 0) { + cmp = a->sign < b->sign; + } + which = cmp > 0 ? 0 : 1; break; default: g_assert_not_reached(); From cc87d3d3818212291cb3dbcbf6b9db8680b4e965 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Wed, 11 Dec 2024 15:31:09 +0000 Subject: [PATCH 70/72] softfloat: Replace WHICH with RET in parts_pick_nan MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Replace the "index" selecting between A and B with a result variable of the proper type. This improves clarity within the function. Signed-off-by: Richard Henderson Reviewed-by: Philippe Mathieu-Daudé Message-id: 20241203203949.483774-12-richard.henderson@linaro.org Signed-off-by: Peter Maydell --- fpu/softfloat-parts.c.inc | 28 +++++++++++++--------------- 1 file changed, 13 insertions(+), 15 deletions(-) diff --git a/fpu/softfloat-parts.c.inc b/fpu/softfloat-parts.c.inc index abe24aeaa0..ba8de7be76 100644 --- a/fpu/softfloat-parts.c.inc +++ b/fpu/softfloat-parts.c.inc @@ -40,7 +40,8 @@ static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, float_status *s) { bool have_snan = false; - int cmp, which; + FloatPartsN *ret; + int cmp; if (is_snan(a->cls) || is_snan(b->cls)) { float_raise(float_flag_invalid | float_flag_invalid_snan, s); @@ -55,21 +56,21 @@ static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, switch (s->float_2nan_prop_rule) { case float_2nan_prop_s_ab: if (have_snan) { - which = is_snan(a->cls) ? 0 : 1; + ret = is_snan(a->cls) ? a : b; break; } /* fall through */ case float_2nan_prop_ab: - which = is_nan(a->cls) ? 0 : 1; + ret = is_nan(a->cls) ? a : b; break; case float_2nan_prop_s_ba: if (have_snan) { - which = is_snan(b->cls) ? 1 : 0; + ret = is_snan(b->cls) ? b : a; break; } /* fall through */ case float_2nan_prop_ba: - which = is_nan(b->cls) ? 1 : 0; + ret = is_nan(b->cls) ? b : a; break; case float_2nan_prop_x87: /* @@ -85,35 +86,32 @@ static FloatPartsN *partsN(pick_nan)(FloatPartsN *a, FloatPartsN *b, */ if (is_snan(a->cls)) { if (!is_snan(b->cls)) { - which = is_qnan(b->cls) ? 1 : 0; + ret = is_qnan(b->cls) ? b : a; break; } } else if (is_qnan(a->cls)) { if (is_snan(b->cls) || !is_qnan(b->cls)) { - which = 0; + ret = a; break; } } else { - which = 1; + ret = b; break; } cmp = frac_cmp(a, b); if (cmp == 0) { cmp = a->sign < b->sign; } - which = cmp > 0 ? 0 : 1; + ret = cmp > 0 ? a : b; break; default: g_assert_not_reached(); } - if (which) { - a = b; + if (is_snan(ret->cls)) { + parts_silence_nan(ret, s); } - if (is_snan(a->cls)) { - parts_silence_nan(a, s); - } - return a; + return ret; } static FloatPartsN *partsN(pick_nan_muladd)(FloatPartsN *a, FloatPartsN *b, From a6240a2ec94ef12e1430e9b3baa06e552634ca8f Mon Sep 17 00:00:00 2001 From: Leif Lindholm Date: Wed, 11 Dec 2024 15:31:09 +0000 Subject: [PATCH 71/72] MAINTAINERS: update email address for Leif Lindholm MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit I'm migrating to Qualcomm's new open source email infrastructure, so update my email address, and update the mailmap to match. Signed-off-by: Leif Lindholm Reviewed-by: Leif Lindholm Reviewed-by: Brian Cain Reviewed-by: Philippe Mathieu-Daudé Tested-by: Philippe Mathieu-Daudé Message-id: 20241205114047.1125842-1-leif.lindholm@oss.qualcomm.com Signed-off-by: Peter Maydell --- .mailmap | 5 +++-- MAINTAINERS | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) diff --git a/.mailmap b/.mailmap index 727ce204b2..5f6df414e1 100644 --- a/.mailmap +++ b/.mailmap @@ -87,8 +87,9 @@ Huacai Chen Huacai Chen James Hogan Juan Quintela -Leif Lindholm -Leif Lindholm +Leif Lindholm +Leif Lindholm +Leif Lindholm Luc Michel Luc Michel Luc Michel diff --git a/MAINTAINERS b/MAINTAINERS index aaf0505a21..9ae6a78ae9 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -915,7 +915,7 @@ F: include/hw/ssi/imx_spi.h SBSA-REF M: Radoslaw Biernacki M: Peter Maydell -R: Leif Lindholm +R: Leif Lindholm R: Marcin Juszkiewicz L: qemu-arm@nongnu.org S: Maintained From 1abe28d519239eea5cf9620bb13149423e5665f8 Mon Sep 17 00:00:00 2001 From: Vikram Garhwal Date: Wed, 11 Dec 2024 15:31:09 +0000 Subject: [PATCH 72/72] MAINTAINERS: Add correct email address for Vikram Garhwal Previously, maintainer role was paused due to inactive email id. Commit id: c009d715721861984c4987bcc78b7ee183e86d75. Signed-off-by: Vikram Garhwal Reviewed-by: Francisco Iglesias Message-id: 20241204184205.12952-1-vikram.garhwal@bytedance.com Signed-off-by: Peter Maydell --- MAINTAINERS | 2 ++ 1 file changed, 2 insertions(+) diff --git a/MAINTAINERS b/MAINTAINERS index 9ae6a78ae9..1d2003a9a1 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -1914,6 +1914,7 @@ F: tests/qtest/fuzz-sb16-test.c Xilinx CAN M: Francisco Iglesias +M: Vikram Garhwal S: Maintained F: hw/net/can/xlnx-* F: include/hw/net/xlnx-* @@ -2673,6 +2674,7 @@ F: include/hw/rx/ CAN bus subsystem and hardware M: Pavel Pisa M: Francisco Iglesias +M: Vikram Garhwal S: Maintained W: https://canbus.pages.fel.cvut.cz/ F: net/can/*