# RUN: llc %s -o - -mtriple=x86_64-unknown-unknown \
# RUN: -experimental-debug-variable-locations \
# RUN: -run-pass=phi-node-elimination,livedebugvars,greedy,virtregrewriter \
# RUN: | FileCheck %s
#
# This test checks that for a very simple PHI, we produce a corresponding
# DBG_PHI instruction, that a DBG_INSTR_REF refers to. Tests the path through
# phi-node-elimination, live debug variables, and then placement after register
# allocation.
#
# Original code, compiled with only -mem2reg, then fed to llc -stop-before...
#
# int ext(int);
# int foo(int bar, int baz) {
# int either = 0;
# if (ext(0))
# either = bar;
# else
# either = baz;
#
# return either;
# }
#
--- |
; ModuleID = 'promoted.ll'
source_filename = "test.c"
target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-unknown-linux-gnu"
define dso_local i32 @foo(i32 %bar, i32 %baz) !dbg !7 {
entry:
call void @llvm.dbg.value(metadata i32 %bar, metadata !11, metadata !DIExpression()), !dbg !12
call void @llvm.dbg.value(metadata i32 %baz, metadata !13, metadata !DIExpression()), !dbg !12
call void @llvm.dbg.value(metadata i32 0, metadata !14, metadata !DIExpression()), !dbg !12
%call = call i32 @ext(i32 0), !dbg !15
%tobool = icmp ne i32 %call, 0, !dbg !15
br i1 %tobool, label %if.end, label %if.else, !dbg !17
if.else: ; preds = %entry
call void @llvm.dbg.value(metadata i32 %baz, metadata !14, metadata !DIExpression()), !dbg !12
br label %if.end
if.end: ; preds = %entry, %if.else
%either.0 = phi i32 [ %baz, %if.else ], [ %bar, %entry ], !dbg !18
call void @llvm.dbg.value(metadata i32 %either.0, metadata !14, metadata !DIExpression()), !dbg !12
ret i32 %either.0, !dbg !19
}
declare dso_local i32 @ext(i32)
; Function Attrs: nounwind readnone speculatable willreturn
declare void @llvm.dbg.value(metadata, metadata, metadata)
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4, !5}
!llvm.ident = !{!6}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None)
!1 = !DIFile(filename: "test.c", directory: ".")
!2 = !{}
!3 = !{i32 7, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = !{i32 1, !"wchar_size", i32 4}
!6 = !{!"."}
!7 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 2, type: !8, scopeLine: 2, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
!8 = !DISubroutineType(types: !9)
!9 = !{!10, !10, !10}
!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!11 = !DILocalVariable(name: "bar", arg: 1, scope: !7, file: !1, line: 2, type: !10)
!12 = !DILocation(line: 0, scope: !7)
!13 = !DILocalVariable(name: "baz", arg: 2, scope: !7, file: !1, line: 2, type: !10)
!14 = !DILocalVariable(name: "either", scope: !7, file: !1, line: 3, type: !10)
!15 = !DILocation(line: 4, column: 7, scope: !16)
!16 = distinct !DILexicalBlock(scope: !7, file: !1, line: 4, column: 7)
!17 = !DILocation(line: 4, column: 7, scope: !7)
!18 = !DILocation(line: 0, scope: !16)
!19 = !DILocation(line: 9, column: 3, scope: !7)
...
---
name: foo
alignment: 16
tracksRegLiveness: true
debugInstrRef: true
registers:
- { id: 0, class: gr32 }
- { id: 1, class: gr32 }
- { id: 2, class: gr32 }
- { id: 3, class: gr32 }
- { id: 4, class: gr32 }
liveins:
- { reg: '$edi', virtual-reg: '%1' }
- { reg: '$esi', virtual-reg: '%2' }
frameInfo:
maxAlignment: 1
adjustsStack: true
hasCalls: true
machineFunctionInfo: {}
body: |
bb.0.entry:
successors: %bb.2(0x50000000), %bb.1(0x30000000)
liveins: $edi, $esi
DBG_VALUE $edi, $noreg, !11, !DIExpression(), debug-location !12
DBG_VALUE $esi, $noreg, !13, !DIExpression(), debug-location !12
%2:gr32 = COPY killed $esi
%1:gr32 = COPY killed $edi
DBG_VALUE 0, $noreg, !14, !DIExpression(), debug-location !12
ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !15
%3:gr32 = MOV32r0 implicit-def dead $eflags
$edi = COPY killed %3, debug-location !15
CALL64pcrel32 @ext, csr_64, implicit $rsp, implicit $ssp, implicit killed $edi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-location !15
ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !15
%4:gr32 = COPY killed $eax, debug-location !15
TEST32rr killed %4, %4, implicit-def $eflags, debug-location !15
JCC_1 %bb.2, 5, implicit killed $eflags, debug-location !17
JMP_1 %bb.1, debug-location !17
bb.1.if.else:
; CHECK-LABEL: bb.2.if.end:
bb.2.if.end:
%0:gr32 = PHI %1, %bb.0, %2, %bb.1, debug-instr-number 1, debug-location !18
DBG_INSTR_REF !14, !DIExpression(DW_OP_LLVM_arg, 0), dbg-instr-ref(1, 0), debug-location !12
; CHECK: DBG_PHI $ebp, 1
; CHECK: DBG_INSTR_REF {{.+}}, dbg-instr-ref(1, 0)
$eax = COPY killed %0, debug-location !19
; Confirm that %0 is allocated in $ebp,
; CHECK: $eax = COPY killed renamable $ebp
RET 0, killed $eax, debug-location !19
...
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