# RUN: llc -mtriple=x86_64-unknown-unknown %s -o - -run-pass=livedebugvalues | FileCheck %s
#
# Fix some of PR42772. Consider the code below: the arguments are forced onto
# the stack by the FORCE_SPILL macro, and go out of liveness if the
# "bees == 2" conditional is not taken. A spill slot is then re-used to
# preserve quux over the second FORCE_SPILL, over-writing the value of either
# "a" or "b". LiveDebugValues should detect when this happens, and terminate
# stack-spill locations when they get overwritten by a new value.
#
# --------8<--------
# #define FORCE_SPILL() \
#   __asm volatile("" : : : \
#                    "rax", "rbx", "rcx", "rdx", "rsi", "rdi", "rbp", "r8", \
#                    "r9", "r10", "r11", "r12", "r13", "r14", "r15")
# 
# volatile int bees = 0;
# 
# long int f(long int a, long int b) {
#   if (bees == 12)
#    return 3;
# 
#   FORCE_SPILL();
#   if (bees == 2)
#     return a - b;
# 
#   int quux = sum(1, 2);
#   FORCE_SPILL();
#   bees++;
#   return quux;
# }
# -------->8--------
#
# CHECK:       ![[ANUM:[0-9]+]] = !DILocalVariable(name: "a"
# CHECK:       ![[BNUM:[0-9]+]] = !DILocalVariable(name: "b"
#
# These variables should be spilt,
# CHECK-LABEL: bb.1.if.end:
# CHECK:       MOV64mr $rsp, 1, $noreg, 16, $noreg, killed renamable $rsi
# CHECK-NEXT:  DBG_VALUE $rsp, 0, ![[BNUM]], !DIExpression(
# CHECK-NEXT:  MOV64mr $rsp, 1, $noreg, 8, $noreg, killed renamable $rdi
# CHECK-NEXT:  DBG_VALUE $rsp, 0, ![[ANUM]], !DIExpression(
# CHECK-NEXT:  INLINEASM
#
# Then the location of "a" should be terminated when overwritten
# CHECK-LABEL: bb.3.if.end3:
# CHECK:       CALL64pcrel32 @sum
# CHECK-NEXT:  MOV64mr $rsp, 1, $noreg, 8, $noreg, $rax
# CHECK-NEXT:  DBG_VALUE $noreg, $noreg, ![[ANUM]], !DIExpression()
# CHECK-NEXT:  INLINEASM

--- |
  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
  target triple = "x86_64-unknown-linux-gnu"
  
  @bees = external global i32, !dbg !0
  
  ; Function Attrs: noinline norecurse nounwind readnone uwtable
  declare i64 @sum(i64, i64)
  
  ; Function Attrs: noinline nounwind uwtable
  define i64 @f(i64 %a, i64 %b) !dbg !12 {
  entry:
    br label %if.end
  if.end:
    br label %if.then2
  if.then2:
    br label %if.end3
  if.end3:
    br label %return
  return:
    ret i64 0
  }
  
  !llvm.dbg.cu = !{!2}
  !llvm.module.flags = !{!8, !9, !10}
  
  !0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression())
  !1 = distinct !DIGlobalVariable(name: "bees", scope: !2, file: !3, line: 6, type: !6, isLocal: false, isDefinition: true)
  !2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5, nameTableKind: None)
  !3 = !DIFile(filename: "pr42772.c", directory: ".")
  !4 = !{}
  !5 = !{!0}
  !6 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !7)
  !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !8 = !{i32 2, !"Dwarf Version", i32 4}
  !9 = !{i32 2, !"Debug Info Version", i32 3}
  !10 = !{i32 1, !"wchar_size", i32 4}
  !12 = distinct !DISubprogram(name: "f", scope: !3, file: !3, line: 15, type: !13, scopeLine: 15, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !2, retainedNodes: !16)
  !13 = !DISubroutineType(types: !14)
  !14 = !{!15, !15, !15}
  !15 = !DIBasicType(name: "long int", size: 64, encoding: DW_ATE_signed)
  !16 = !{!17, !18, !19}
  !17 = !DILocalVariable(name: "a", arg: 1, scope: !12, file: !3, line: 15, type: !15)
  !18 = !DILocalVariable(name: "b", arg: 2, scope: !12, file: !3, line: 15, type: !15)
  !19 = !DILocalVariable(name: "quux", scope: !12, file: !3, line: 23, type: !7)
  !28 = !DILocation(line: 1, column: 1, scope: !12)

...
---
name:            f
tracksRegLiveness: true
liveins:
  - { reg: '$rdi', virtual-reg: '' }
  - { reg: '$rsi', virtual-reg: '' }
frameInfo:
  stackSize:       72
  offsetAdjustment: -72
  maxAlignment:    8
  adjustsStack:    true
  hasCalls:        true
  cvBytesOfCalleeSavedRegisters: 48
fixedStack:
  - { id: 0, type: spill-slot, offset: -56, size: 8, alignment: 8, stack-id: default, 
      callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '', 
      debug-info-expression: '', debug-info-location: '' }
  - { id: 1, type: spill-slot, offset: -48, size: 8, alignment: 16, stack-id: default, 
      callee-saved-register: '$r12', callee-saved-restored: true, debug-info-variable: '', 
      debug-info-expression: '', debug-info-location: '' }
  - { id: 2, type: spill-slot, offset: -40, size: 8, alignment: 8, stack-id: default, 
      callee-saved-register: '$r13', callee-saved-restored: true, debug-info-variable: '', 
      debug-info-expression: '', debug-info-location: '' }
  - { id: 3, type: spill-slot, offset: -32, size: 8, alignment: 16, stack-id: default, 
      callee-saved-register: '$r14', callee-saved-restored: true, debug-info-variable: '', 
      debug-info-expression: '', debug-info-location: '' }
  - { id: 4, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default, 
      callee-saved-register: '$r15', callee-saved-restored: true, debug-info-variable: '', 
      debug-info-expression: '', debug-info-location: '' }
  - { id: 5, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default, 
      callee-saved-register: '$rbp', callee-saved-restored: true, debug-info-variable: '', 
      debug-info-expression: '', debug-info-location: '' }
stack:
  - { id: 0, name: '', type: spill-slot, offset: -72, size: 8, alignment: 8, 
      stack-id: default, callee-saved-register: '', callee-saved-restored: true, 
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
  - { id: 1, name: '', type: spill-slot, offset: -64, size: 8, alignment: 8, 
      stack-id: default, callee-saved-register: '', callee-saved-restored: true, 
      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body:             |
  bb.0.entry:
    successors: %bb.4, %bb.1
    liveins: $rdi, $rsi, $rbp, $r15, $r14, $r13, $r12, $rbx
  
    DBG_VALUE $rdi, $noreg, !17, !DIExpression(), debug-location !28
    DBG_VALUE $rdi, $noreg, !17, !DIExpression(), debug-location !28
    DBG_VALUE $rsi, $noreg, !18, !DIExpression(), debug-location !28
    DBG_VALUE $rsi, $noreg, !18, !DIExpression(), debug-location !28
    frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp, debug-location !28
    frame-setup PUSH64r killed $r15, implicit-def $rsp, implicit $rsp, debug-location !28
    frame-setup PUSH64r killed $r14, implicit-def $rsp, implicit $rsp, debug-location !28
    frame-setup PUSH64r killed $r13, implicit-def $rsp, implicit $rsp, debug-location !28
    frame-setup PUSH64r killed $r12, implicit-def $rsp, implicit $rsp, debug-location !28
    frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp, debug-location !28
    $rsp = frame-setup SUB64ri8 $rsp, 24, implicit-def dead $eflags
    renamable $ecx = MOV32rm $rip, 1, $noreg, @bees, $noreg, debug-location !28 :: (volatile dereferenceable load 4 from @bees)
    $eax = MOV32ri 3, implicit-def $rax
    CMP32ri8 killed renamable $ecx, 12, implicit-def $eflags, debug-location !28
    JCC_1 %bb.4, 4, implicit $eflags, debug-location !28
  
  bb.1.if.end:
    successors: %bb.2, %bb.3
    liveins: $rdi, $rsi
  
    MOV64mr $rsp, 1, $noreg, 16, $noreg, killed renamable $rsi :: (store 8 into %stack.1)
    MOV64mr $rsp, 1, $noreg, 8, $noreg, killed renamable $rdi :: (store 8 into %stack.0)
    INLINEASM &"", 1, 12, implicit-def dead early-clobber $rax, 12, implicit-def dead early-clobber $rbx, 12, implicit-def dead early-clobber $rcx, 12, implicit-def dead early-clobber $rdx, 12, implicit-def dead early-clobber $rsi, 12, implicit-def dead early-clobber $rdi, 12, implicit-def dead early-clobber $rbp, 12, implicit-def dead early-clobber $r8, 12, implicit-def dead early-clobber $r9, 12, implicit-def dead early-clobber $r10, 12, implicit-def dead early-clobber $r11, 12, implicit-def dead early-clobber $r12, 12, implicit-def dead early-clobber $r13, 12, implicit-def dead early-clobber $r14, 12, implicit-def dead early-clobber $r15, 12, implicit-def dead early-clobber $df, 12, implicit-def dead early-clobber $fpsw, 12, implicit-def dead early-clobber $eflags, debug-location !28
    renamable $eax = MOV32rm $rip, 1, $noreg, @bees, $noreg, debug-location !28 :: (volatile dereferenceable load 4 from @bees)
    CMP32ri8 killed renamable $eax, 2, implicit-def $eflags, debug-location !28
    JCC_1 %bb.3, 5, implicit killed $eflags, debug-location !28
  
  bb.2.if.then2:
    successors: %bb.4
  
    renamable $rax = MOV64rm $rsp, 1, $noreg, 8, $noreg :: (load 8 from %stack.0)
    renamable $rax = SUB64rm killed renamable $rax, $rsp, 1, $noreg, 16, $noreg, implicit-def dead $eflags, debug-location !28 :: (load 8 from %stack.1)
    JMP_1 %bb.4
  
  bb.3.if.end3:
    successors: %bb.4
  
    $edi = MOV32ri 1, implicit-def $rdi, debug-location !28
    $esi = MOV32ri 2, implicit-def $rsi, debug-location !28
    CALL64pcrel32 @sum, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit $rsi, implicit-def $rsp, implicit-def $ssp, implicit-def $rax, debug-location !28
    MOV64mr $rsp, 1, $noreg, 8, $noreg, $rax :: (store 8 into %stack.0)
    INLINEASM &"", 1, 12, implicit-def dead early-clobber $rax, 12, implicit-def dead early-clobber $rbx, 12, implicit-def dead early-clobber $rcx, 12, implicit-def dead early-clobber $rdx, 12, implicit-def dead early-clobber $rsi, 12, implicit-def dead early-clobber $rdi, 12, implicit-def dead early-clobber $rbp, 12, implicit-def dead early-clobber $r8, 12, implicit-def dead early-clobber $r9, 12, implicit-def dead early-clobber $r10, 12, implicit-def dead early-clobber $r11, 12, implicit-def dead early-clobber $r12, 12, implicit-def dead early-clobber $r13, 12, implicit-def dead early-clobber $r14, 12, implicit-def dead early-clobber $r15, 12, implicit-def dead early-clobber $df, 12, implicit-def dead early-clobber $fpsw, 12, implicit-def dead early-clobber $eflags, debug-location !28
    ADD32mi8 $rip, 1, $noreg, @bees, $noreg, 1, implicit-def dead $eflags, debug-location !28 :: (volatile store 4 into @bees), (volatile dereferenceable load 4 from @bees)
    renamable $rax = MOVSX64rm32 $rsp, 1, $noreg, 8, $noreg, debug-location !28 :: (load 4 from %stack.0, align 8)
  
  bb.4.return:
    liveins: $rax
  
    $rsp = frame-destroy ADD64ri8 $rsp, 24, implicit-def dead $eflags, debug-location !28
    $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
    $r12 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
    $r13 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
    $r14 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
    $r15 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
    $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !28
    RETQ $rax, debug-location !28

...