last-inst-bundled.mir 7.35 KB
# RUN: llc -run-pass=livedebugvalues -march=mips -o - %s | FileCheck %s
#
#"last-instr-bundled.c"
#extern void set_cond(int, int*);
#extern void do_something(char *,int);
#
#void foo (int argument)
#{
#  int condition;
#  char *string;
#
#  set_cond(argument,&condition);
#
#  if (condition)
#    do_something(string,argument);
#}
#
# reproduce:
# clang --target=mips-linux-gnu -g -O1 -S -emit-llvm last-instr-bundled
# llc -stop-before=livedebugvalues < last-instr-bundled.ll > last-instr-bundled.mir
#
# Check that last bundled instruction of block gets recognized as end of basic block.
# CHECK: bb.2.if.end
# CHECK-NEXT: DBG_VALUE $s0, $noreg, !12, !DIExpression(), debug-location !17

--- |
  ; ModuleID = '<stdin>'
  source_filename = "last-inst-bundled.c"
  target datalayout = "E-m:m-p:32:32-i8:8:32-i16:16:32-i64:64-n32-S64"
  target triple = "mips--linux-gnu"

  define void @foo(i32 signext %argument) local_unnamed_addr !dbg !7 {
  entry:
    %condition = alloca i32, align 4
    call void @llvm.dbg.value(metadata i32 %argument, metadata !12, metadata !DIExpression()), !dbg !17
    %0 = bitcast i32* %condition to i8*, !dbg !18
    call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %0), !dbg !18
    call void @llvm.dbg.value(metadata i32* %condition, metadata !13, metadata !DIExpression()), !dbg !19
    call void @set_cond(i32 signext %argument, i32* nonnull %condition), !dbg !20
    %1 = load i32, i32* %condition, align 4, !dbg !21, !tbaa !23
    call void @llvm.dbg.value(metadata i32 %1, metadata !13, metadata !DIExpression()), !dbg !19
    %tobool = icmp eq i32 %1, 0, !dbg !21
    br i1 %tobool, label %if.end, label %if.then, !dbg !27

  if.then:                                          ; preds = %entry
    call void @do_something(i8* undef, i32 signext %argument), !dbg !28
    br label %if.end, !dbg !28

  if.end:                                           ; preds = %if.then, %entry
    %2 = bitcast i32* %condition to i8*
    call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull %2), !dbg !29
    ret void, !dbg !29
  }

  ; Function Attrs: argmemonly nounwind
  declare void @llvm.lifetime.start.p0i8(i64, i8* nocapture) #0

  declare void @set_cond(i32 signext, i32*) local_unnamed_addr

  declare void @do_something(i8*, i32 signext) local_unnamed_addr

  ; Function Attrs: argmemonly nounwind
  declare void @llvm.lifetime.end.p0i8(i64, i8* nocapture) #0

  ; Function Attrs: nounwind readnone speculatable
  declare void @llvm.dbg.value(metadata, metadata, metadata) #1

  ; Function Attrs: nounwind
  declare void @llvm.stackprotector(i8*, i8**) #2

  attributes #0 = { argmemonly nounwind }
  attributes #1 = { nounwind readnone speculatable }
  attributes #2 = { nounwind }

  !llvm.dbg.cu = !{!0}
  !llvm.module.flags = !{!3, !4, !5}
  !llvm.ident = !{!6}

  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
  !1 = !DIFile(filename: "last-inst-bundled.c", directory: "/")
  !2 = !{}
  !3 = !{i32 2, !"Dwarf Version", i32 4}
  !4 = !{i32 2, !"Debug Info Version", i32 3}
  !5 = !{i32 1, !"wchar_size", i32 4}
  !6 = !{!"clang version 6.0.0 "}
  !7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 4, type: !8, isLocal: false, isDefinition: true, scopeLine: 5, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !11)
  !8 = !DISubroutineType(types: !9)
  !9 = !{null, !10}
  !10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
  !11 = !{!12, !13, !14}
  !12 = !DILocalVariable(name: "argument", arg: 1, scope: !7, file: !1, line: 4, type: !10)
  !13 = !DILocalVariable(name: "condition", scope: !7, file: !1, line: 6, type: !10)
  !14 = !DILocalVariable(name: "string", scope: !7, file: !1, line: 7, type: !15)
  !15 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !16, size: 32)
  !16 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char)
  !17 = !DILocation(line: 4, column: 15, scope: !7)
  !18 = !DILocation(line: 6, column: 3, scope: !7)
  !19 = !DILocation(line: 6, column: 7, scope: !7)
  !20 = !DILocation(line: 9, column: 3, scope: !7)
  !21 = !DILocation(line: 11, column: 7, scope: !22)
  !22 = distinct !DILexicalBlock(scope: !7, file: !1, line: 11, column: 7)
  !23 = !{!24, !24, i64 0}
  !24 = !{!"int", !25, i64 0}
  !25 = !{!"omnipotent char", !26, i64 0}
  !26 = !{!"Simple C/C++ TBAA"}
  !27 = !DILocation(line: 11, column: 7, scope: !7)
  !28 = !DILocation(line: 12, column: 5, scope: !22)
  !29 = !DILocation(line: 13, column: 1, scope: !7)

...
---
name:            foo
alignment:       4
exposesReturnsTwice: false
legalized:       false
regBankSelected: false
selected:        false
tracksRegLiveness: false
registers:
liveins:
  - { reg: '$a0', virtual-reg: '' }
frameInfo:
  isFrameAddressTaken: false
  isReturnAddressTaken: false
  hasStackMap:     false
  hasPatchPoint:   false
  stackSize:       32
  offsetAdjustment: 0
  maxAlignment:    4
  adjustsStack:    true
  hasCalls:        true
  stackProtector:  ''
  maxCallFrameSize: 16
  hasOpaqueSPAdjustment: false
  hasVAStart:      false
  hasMustTailInVarArgFunc: false
  savePoint:       ''
  restorePoint:    ''
fixedStack:
stack:
  - { id: 0, name: condition, type: default, offset: -12, size: 4, alignment: 4,
      stack-id: default, callee-saved-register: '', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '',
      debug-info-location: '' }
  - { id: 1, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
      stack-id: default, callee-saved-register: '$ra', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '',
      debug-info-location: '' }
  - { id: 2, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
      stack-id: default, callee-saved-register: '$s0', callee-saved-restored: true,
      debug-info-variable: '', debug-info-expression: '',
      debug-info-location: '' }
constants:
body:             |
  bb.0.entry:
    successors: %bb.2(0x30000000), %bb.1(0x50000000)

    $sp = ADDiu $sp, -32
    CFI_INSTRUCTION def_cfa_offset 32
    SW killed $ra, $sp, 28 :: (store 4 into %stack.1)
    SW killed $s0, $sp, 24 :: (store 4 into %stack.2)
    CFI_INSTRUCTION offset $ra_64, -4
    CFI_INSTRUCTION offset $s0_64, -8
    DBG_VALUE $a0, $noreg, !12, !DIExpression(), debug-location !17
    $s0 = OR $a0, $zero
    DBG_VALUE $s0, $noreg, !12, !DIExpression(), debug-location !17
    DBG_VALUE $sp, 0, !13, !DIExpression(DW_OP_plus_uconst, 20), debug-location !19
    JAL @set_cond, csr_o32, implicit-def dead $ra, implicit $a0, implicit $a1, implicit-def $sp, debug-location !20 {
      renamable $a1 = LEA_ADDiu $sp, 20
    }
    renamable $at = LW $sp, 20, debug-location !21 :: (dereferenceable load 4 from %ir.condition, !tbaa !23)
    DBG_VALUE $at, $noreg, !13, !DIExpression(), debug-location !19
    BEQ killed renamable $at, $zero, %bb.2, implicit-def $at, debug-location !27 {
      NOP debug-location !27
    }

  bb.1.if.then:
    successors: %bb.2(0x80000000)

    JAL @do_something, csr_o32, implicit-def dead $ra, implicit undef $a0, implicit $a1, implicit-def $sp, debug-location !28 {
      $a1 = OR killed $s0, $zero, debug-location !28
    }

  bb.2.if.end:
    $s0 = LW $sp, 24, debug-location !29 :: (load 4 from %stack.2)
    $ra = LW $sp, 28, debug-location !29 :: (load 4 from %stack.1)
    PseudoReturn undef $ra, debug-location !29 {
      $sp = ADDiu $sp, 32
    }

...