From d04fb4943f642bea677ca38df5f906bde41a199a Mon Sep 17 00:00:00 2001
From: Rich Felker <dalias@aerifal.cx>
Date: Tue, 30 Jun 2020 16:35:55 -0400
Subject: [PATCH] add patch fixing broken m68k sqrt

gcc pr 95921. the m68k sqrt rtl handles excess precision wrong. I
couldn't figure out how to make gcc generate the insn only for long
double, but since long double usage is rare anyway, just remove it.
this can be replaced with a proper fix later if there's ever one
upstream.
---
 patches/gcc-5.3.0/0019-m68k-sqrt.diff | 38 +++++++++++++++++++++++++++
 patches/gcc-6.5.0/0024-m68k-sqrt.diff | 38 +++++++++++++++++++++++++++
 patches/gcc-7.3.0/0021-m68k-sqrt.diff | 38 +++++++++++++++++++++++++++
 patches/gcc-8.3.0/0018-m68k-sqrt.diff | 38 +++++++++++++++++++++++++++
 patches/gcc-9.2.0/0018-m68k-sqrt.diff | 38 +++++++++++++++++++++++++++
 5 files changed, 190 insertions(+)
 create mode 100644 patches/gcc-5.3.0/0019-m68k-sqrt.diff
 create mode 100644 patches/gcc-6.5.0/0024-m68k-sqrt.diff
 create mode 100644 patches/gcc-7.3.0/0021-m68k-sqrt.diff
 create mode 100644 patches/gcc-8.3.0/0018-m68k-sqrt.diff
 create mode 100644 patches/gcc-9.2.0/0018-m68k-sqrt.diff

diff --git a/patches/gcc-5.3.0/0019-m68k-sqrt.diff b/patches/gcc-5.3.0/0019-m68k-sqrt.diff
new file mode 100644
index 0000000..3315939
--- /dev/null
+++ b/patches/gcc-5.3.0/0019-m68k-sqrt.diff
@@ -0,0 +1,38 @@
+--- gcc-9.2.0.orig/gcc/config/m68k/m68k.md	2019-01-01 07:31:55.000000000 -0500
++++ gcc-9.2.0/gcc/config/m68k/m68k.md	2020-06-30 15:56:20.061868526 -0400
+@@ -4121,35 +4121,6 @@
+   return "f<FP:prec>neg%.<FP:prec> %1,%0";
+ })
+ 
+-;; Sqrt instruction for the 68881
+-
+-(define_expand "sqrt<mode>2"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "")))]
+-  "TARGET_HARD_FLOAT"
+-  "")
+-
+-(define_insn "sqrt<mode>2_68881"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg>m")))]
+-  "TARGET_68881"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:round>sqrt%.x %1,%0";
+-  return "f<FP:round>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+-
+-(define_insn "sqrt<mode>2_cf"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg><Q>U")))]
+-  "TARGET_COLDFIRE_FPU"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:prec>sqrt%.d %1,%0";
+-  return "f<FP:prec>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+ ;; Absolute value instructions
+ ;; If using software floating point, just zero the sign bit.
+ 
diff --git a/patches/gcc-6.5.0/0024-m68k-sqrt.diff b/patches/gcc-6.5.0/0024-m68k-sqrt.diff
new file mode 100644
index 0000000..3315939
--- /dev/null
+++ b/patches/gcc-6.5.0/0024-m68k-sqrt.diff
@@ -0,0 +1,38 @@
+--- gcc-9.2.0.orig/gcc/config/m68k/m68k.md	2019-01-01 07:31:55.000000000 -0500
++++ gcc-9.2.0/gcc/config/m68k/m68k.md	2020-06-30 15:56:20.061868526 -0400
+@@ -4121,35 +4121,6 @@
+   return "f<FP:prec>neg%.<FP:prec> %1,%0";
+ })
+ 
+-;; Sqrt instruction for the 68881
+-
+-(define_expand "sqrt<mode>2"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "")))]
+-  "TARGET_HARD_FLOAT"
+-  "")
+-
+-(define_insn "sqrt<mode>2_68881"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg>m")))]
+-  "TARGET_68881"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:round>sqrt%.x %1,%0";
+-  return "f<FP:round>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+-
+-(define_insn "sqrt<mode>2_cf"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg><Q>U")))]
+-  "TARGET_COLDFIRE_FPU"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:prec>sqrt%.d %1,%0";
+-  return "f<FP:prec>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+ ;; Absolute value instructions
+ ;; If using software floating point, just zero the sign bit.
+ 
diff --git a/patches/gcc-7.3.0/0021-m68k-sqrt.diff b/patches/gcc-7.3.0/0021-m68k-sqrt.diff
new file mode 100644
index 0000000..3315939
--- /dev/null
+++ b/patches/gcc-7.3.0/0021-m68k-sqrt.diff
@@ -0,0 +1,38 @@
+--- gcc-9.2.0.orig/gcc/config/m68k/m68k.md	2019-01-01 07:31:55.000000000 -0500
++++ gcc-9.2.0/gcc/config/m68k/m68k.md	2020-06-30 15:56:20.061868526 -0400
+@@ -4121,35 +4121,6 @@
+   return "f<FP:prec>neg%.<FP:prec> %1,%0";
+ })
+ 
+-;; Sqrt instruction for the 68881
+-
+-(define_expand "sqrt<mode>2"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "")))]
+-  "TARGET_HARD_FLOAT"
+-  "")
+-
+-(define_insn "sqrt<mode>2_68881"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg>m")))]
+-  "TARGET_68881"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:round>sqrt%.x %1,%0";
+-  return "f<FP:round>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+-
+-(define_insn "sqrt<mode>2_cf"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg><Q>U")))]
+-  "TARGET_COLDFIRE_FPU"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:prec>sqrt%.d %1,%0";
+-  return "f<FP:prec>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+ ;; Absolute value instructions
+ ;; If using software floating point, just zero the sign bit.
+ 
diff --git a/patches/gcc-8.3.0/0018-m68k-sqrt.diff b/patches/gcc-8.3.0/0018-m68k-sqrt.diff
new file mode 100644
index 0000000..3315939
--- /dev/null
+++ b/patches/gcc-8.3.0/0018-m68k-sqrt.diff
@@ -0,0 +1,38 @@
+--- gcc-9.2.0.orig/gcc/config/m68k/m68k.md	2019-01-01 07:31:55.000000000 -0500
++++ gcc-9.2.0/gcc/config/m68k/m68k.md	2020-06-30 15:56:20.061868526 -0400
+@@ -4121,35 +4121,6 @@
+   return "f<FP:prec>neg%.<FP:prec> %1,%0";
+ })
+ 
+-;; Sqrt instruction for the 68881
+-
+-(define_expand "sqrt<mode>2"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "")))]
+-  "TARGET_HARD_FLOAT"
+-  "")
+-
+-(define_insn "sqrt<mode>2_68881"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg>m")))]
+-  "TARGET_68881"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:round>sqrt%.x %1,%0";
+-  return "f<FP:round>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+-
+-(define_insn "sqrt<mode>2_cf"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg><Q>U")))]
+-  "TARGET_COLDFIRE_FPU"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:prec>sqrt%.d %1,%0";
+-  return "f<FP:prec>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+ ;; Absolute value instructions
+ ;; If using software floating point, just zero the sign bit.
+ 
diff --git a/patches/gcc-9.2.0/0018-m68k-sqrt.diff b/patches/gcc-9.2.0/0018-m68k-sqrt.diff
new file mode 100644
index 0000000..3315939
--- /dev/null
+++ b/patches/gcc-9.2.0/0018-m68k-sqrt.diff
@@ -0,0 +1,38 @@
+--- gcc-9.2.0.orig/gcc/config/m68k/m68k.md	2019-01-01 07:31:55.000000000 -0500
++++ gcc-9.2.0/gcc/config/m68k/m68k.md	2020-06-30 15:56:20.061868526 -0400
+@@ -4121,35 +4121,6 @@
+   return "f<FP:prec>neg%.<FP:prec> %1,%0";
+ })
+ 
+-;; Sqrt instruction for the 68881
+-
+-(define_expand "sqrt<mode>2"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "")))]
+-  "TARGET_HARD_FLOAT"
+-  "")
+-
+-(define_insn "sqrt<mode>2_68881"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg>m")))]
+-  "TARGET_68881"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:round>sqrt%.x %1,%0";
+-  return "f<FP:round>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+-
+-(define_insn "sqrt<mode>2_cf"
+-  [(set (match_operand:FP 0 "nonimmediate_operand" "=f")
+-	(sqrt:FP (match_operand:FP 1 "general_operand" "f<FP:dreg><Q>U")))]
+-  "TARGET_COLDFIRE_FPU"
+-{
+-  if (FP_REG_P (operands[1]))
+-    return "f<FP:prec>sqrt%.d %1,%0";
+-  return "f<FP:prec>sqrt%.<FP:prec> %1,%0";
+-}
+-  [(set_attr "type" "fsqrt")])
+ ;; Absolute value instructions
+ ;; If using software floating point, just zero the sign bit.
+