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| # 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
}
...
|