Skip to content

[DebugInfo][LoopDistribute] Salvage debug values using dead instructions in the distributed loops #137124

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 4 commits into from
May 12, 2025
Merged

[DebugInfo][LoopDistribute] Salvage debug values using dead instructions in the distributed loops #137124

Show file tree
Hide file tree
Changes from 2 commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
9bc06df
Fix #136532: salvage debug values in the distributed loops
Apochens Apr 24, 2025
8b6aabe
add the check discription to the regression test
Apochens Apr 24, 2025
c6cd1b6
simplify the regression test
Apochens May 6, 2025
0da24af
refine test
Apochens May 6, 2025
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 2 additions & 0 deletions llvm/lib/Transforms/Scalar/LoopDistribute.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -58,6 +58,7 @@
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/LoopVersioning.h"
#include "llvm/Transforms/Utils/ValueMapper.h"
Expand Down Expand Up @@ -224,6 +225,7 @@ class InstPartition {
// Delete the instructions backwards, as it has a reduced likelihood of
// having to update as many def-use and use-def chains.
for (auto *Inst : reverse(Unused)) {
salvageDebugInfo(*Inst);
if (!Inst->use_empty())
Inst->replaceAllUsesWith(PoisonValue::get(Inst->getType()));
Inst->eraseFromParent();
Expand Down
159 changes: 159 additions & 0 deletions llvm/test/Transforms/LoopDistribute/salvage-dbg-values-in-distributed-loops.ll
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,159 @@
; RUN: opt -passes=loop-distribute -enable-loop-distribute -S < %s | FileCheck %s

; Check that removeUnusedInsts() salvages `dbg_value`s which use dead
; instructions in the distributed loops.

define void @f(ptr noalias %a, ptr noalias %b, ptr noalias %c, ptr noalias %d, ptr noalias %e) !dbg !5 {
; CHECK-LABEL: define void @f(
; CHECK-SAME: ptr noalias [[A:%.*]], ptr noalias [[B:%.*]], ptr noalias [[C:%.*]], ptr noalias [[D:%.*]], ptr noalias [[E:%.*]])

; CHECK: for.body.ldist1:
; CHECK-NEXT: [[IND_LDIST1:%.*]] = phi i64 [ 0, %[[ENTRY_SPLIT_LDIST1:.*]] ], [ [[ADD_LDIST1:%.*]], %for.body.ldist1 ], !dbg [[DBG28:![0-9]+]]

; CHECK: store i32
; CHECK-NEXT: #dbg_value(!DIArgList(ptr [[D]], i64 [[IND_LDIST1]]), [[META19:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 4, DW_OP_mul, DW_OP_plus, DW_OP_stack_value), [[META37:![0-9]+]])
; CHECK-NEXT: #dbg_value(i32 poison, [[META20:![0-9]+]], !DIExpression(), [[META38:![0-9]+]])
; CHECK-NEXT: #dbg_value(!DIArgList(ptr [[E]], i64 [[IND_LDIST1]]), [[META21:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 4, DW_OP_mul, DW_OP_plus, DW_OP_stack_value), [[META39:![0-9]+]])
; CHECK-NEXT: #dbg_value(i32 poison, [[META22:![0-9]+]], !DIExpression(), [[META40:![0-9]+]])
; CHECK-NEXT: #dbg_value(!DIArgList(i32 poison, i32 poison), [[META23:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_mul, DW_OP_stack_value), [[META41:![0-9]+]])
; CHECK-NEXT: #dbg_value(!DIArgList(ptr [[C]], i64 [[IND_LDIST1]]), [[META24:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 4, DW_OP_mul, DW_OP_plus, DW_OP_stack_value), [[META42:![0-9]+]])
; CHECK-NEXT: [[EXITCOND_LDIST1:%.*]] = icmp eq i64 [[ADD_LDIST1]], 20, !dbg [[DBG43:![0-9]+]]
; CHECK-NEXT: #dbg_value(i1 [[EXITCOND_LDIST1]], [[META25:![0-9]+]], !DIExpression(), [[DBG43]])
; CHECK-NEXT: br i1 [[EXITCOND_LDIST1]], label %[[ENTRY_SPLIT:.*]], label %for.body.ldist1, !dbg [[DBG44:![0-9]+]]

; CHECK: for.body:
; CHECK-NEXT: [[IND:%.*]] = phi i64 [ 0, %[[ENTRY_SPLIT:.*]] ], [ [[ADD:%.*]], %for.body ], !dbg [[DBG28]]
; CHECK-NEXT: #dbg_value(i64 [[IND]], [[META9:![0-9]+]], !DIExpression(), [[DBG28]])
; CHECK-NEXT: #dbg_value(!DIArgList(ptr [[A]], i64 [[IND]]), [[META11:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 4, DW_OP_mul, DW_OP_plus, DW_OP_stack_value), [[DBG29:![0-9]+]])
; CHECK-NEXT: #dbg_value(i32 poison, [[META12:![0-9]+]], !DIExpression(), [[DBG30:![0-9]+]])
; CHECK-NEXT: #dbg_value(!DIArgList(ptr [[B]], i64 [[IND]]), [[META14:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 4, DW_OP_mul, DW_OP_plus, DW_OP_stack_value), [[DBG31:![0-9]+]])
; CHECK-NEXT: #dbg_value(i32 poison, [[META15:![0-9]+]], !DIExpression(), [[DBG32:![0-9]+]])
; CHECK-NEXT: #dbg_value(!DIArgList(i32 poison, i32 poison), [[META16:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_mul, DW_OP_stack_value), [[DBG33:![0-9]+]])
; CHECK-NEXT: [[ADD]] = add nuw nsw i64 [[IND]], 1, !dbg [[DBG34:![0-9]+]]
; CHECK-NEXT: #dbg_value(i64 [[ADD]], [[META17:![0-9]+]], !DIExpression(), [[DBG34]])
; CHECK-NEXT: #dbg_value(!DIArgList(ptr [[A]], i64 [[ADD]]), [[META18:![0-9]+]], !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 1, DW_OP_constu, 4, DW_OP_mul, DW_OP_plus, DW_OP_stack_value), [[DBG35:![0-9]+]])
;
entry:
br label %for.body, !dbg !27

for.body: ; preds = %for.body, %entry
%ind = phi i64 [ 0, %entry ], [ %add, %for.body ], !dbg !28
#dbg_value(i64 %ind, !9, !DIExpression(), !28)
%arrayidxA = getelementptr inbounds i32, ptr %a, i64 %ind, !dbg !29
#dbg_value(ptr %arrayidxA, !11, !DIExpression(), !29)
%loadA = load i32, ptr %arrayidxA, align 4, !dbg !30
#dbg_value(i32 %loadA, !12, !DIExpression(), !30)
%arrayidxB = getelementptr inbounds i32, ptr %b, i64 %ind, !dbg !31
#dbg_value(ptr %arrayidxB, !14, !DIExpression(), !31)
%loadB = load i32, ptr %arrayidxB, align 4, !dbg !32
#dbg_value(i32 %loadB, !15, !DIExpression(), !32)
%mulA = mul i32 %loadB, %loadA, !dbg !33
#dbg_value(i32 %mulA, !16, !DIExpression(), !33)
%add = add nuw nsw i64 %ind, 1, !dbg !34
#dbg_value(i64 %add, !17, !DIExpression(), !34)
%arrayidxA_plus_4 = getelementptr inbounds i32, ptr %a, i64 %add, !dbg !35
#dbg_value(ptr %arrayidxA_plus_4, !18, !DIExpression(), !35)
store i32 %mulA, ptr %arrayidxA_plus_4, align 4, !dbg !36
%arrayidxD = getelementptr inbounds i32, ptr %d, i64 %ind, !dbg !37
#dbg_value(ptr %arrayidxD, !19, !DIExpression(), !37)
%loadD = load i32, ptr %arrayidxD, align 4, !dbg !38
#dbg_value(i32 %loadD, !20, !DIExpression(), !38)
%arrayidxE = getelementptr inbounds i32, ptr %e, i64 %ind, !dbg !39
#dbg_value(ptr %arrayidxE, !21, !DIExpression(), !39)
%loadE = load i32, ptr %arrayidxE, align 4, !dbg !40
#dbg_value(i32 %loadE, !22, !DIExpression(), !40)
%mulC = mul i32 %loadD, %loadE, !dbg !41
#dbg_value(i32 %mulC, !23, !DIExpression(), !41)
%arrayidxC = getelementptr inbounds i32, ptr %c, i64 %ind, !dbg !42
#dbg_value(ptr %arrayidxC, !24, !DIExpression(), !42)
store i32 %mulC, ptr %arrayidxC, align 4, !dbg !43
%exitcond = icmp eq i64 %add, 20, !dbg !44
#dbg_value(i1 %exitcond, !25, !DIExpression(), !44)
br i1 %exitcond, label %for.end, label %for.body, !dbg !45

for.end: ; preds = %for.body
ret void, !dbg !46
}

!llvm.dbg.cu = !{!0}
!llvm.debugify = !{!2, !3}
!llvm.module.flags = !{!4}

!0 = distinct !DICompileUnit(language: DW_LANG_C, file: !1, producer: "debugify", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug)
!1 = !DIFile(filename: "/app/example.ll", directory: "/")
!2 = !{i32 20}
!3 = !{i32 15}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = distinct !DISubprogram(name: "f", linkageName: "f", scope: null, file: !1, line: 1, type: !6, scopeLine: 1, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !8)
!6 = !DISubroutineType(types: !7)
!7 = !{}
!8 = !{!9, !11, !12, !14, !15, !16, !17, !18, !19, !20, !21, !22, !23, !24, !25}
!9 = !DILocalVariable(name: "1", scope: !5, file: !1, line: 2, type: !10)
!10 = !DIBasicType(name: "ty64", size: 64, encoding: DW_ATE_unsigned)
!11 = !DILocalVariable(name: "2", scope: !5, file: !1, line: 3, type: !10)
!12 = !DILocalVariable(name: "3", scope: !5, file: !1, line: 4, type: !13)
!13 = !DIBasicType(name: "ty32", size: 32, encoding: DW_ATE_unsigned)
!14 = !DILocalVariable(name: "4", scope: !5, file: !1, line: 5, type: !10)
!15 = !DILocalVariable(name: "5", scope: !5, file: !1, line: 6, type: !13)
!16 = !DILocalVariable(name: "6", scope: !5, file: !1, line: 7, type: !13)
!17 = !DILocalVariable(name: "7", scope: !5, file: !1, line: 8, type: !10)
!18 = !DILocalVariable(name: "8", scope: !5, file: !1, line: 9, type: !10)
!19 = !DILocalVariable(name: "9", scope: !5, file: !1, line: 11, type: !10)
!20 = !DILocalVariable(name: "10", scope: !5, file: !1, line: 12, type: !13)
!21 = !DILocalVariable(name: "11", scope: !5, file: !1, line: 13, type: !10)
!22 = !DILocalVariable(name: "12", scope: !5, file: !1, line: 14, type: !13)
!23 = !DILocalVariable(name: "13", scope: !5, file: !1, line: 15, type: !13)
!24 = !DILocalVariable(name: "14", scope: !5, file: !1, line: 16, type: !10)
!25 = !DILocalVariable(name: "15", scope: !5, file: !1, line: 18, type: !26)
!26 = !DIBasicType(name: "ty8", size: 8, encoding: DW_ATE_unsigned)
!27 = !DILocation(line: 1, column: 1, scope: !5)
!28 = !DILocation(line: 2, column: 1, scope: !5)
!29 = !DILocation(line: 3, column: 1, scope: !5)
!30 = !DILocation(line: 4, column: 1, scope: !5)
!31 = !DILocation(line: 5, column: 1, scope: !5)
!32 = !DILocation(line: 6, column: 1, scope: !5)
!33 = !DILocation(line: 7, column: 1, scope: !5)
!34 = !DILocation(line: 8, column: 1, scope: !5)
!35 = !DILocation(line: 9, column: 1, scope: !5)
!36 = !DILocation(line: 10, column: 1, scope: !5)
!37 = !DILocation(line: 11, column: 1, scope: !5)
!38 = !DILocation(line: 12, column: 1, scope: !5)
!39 = !DILocation(line: 13, column: 1, scope: !5)
!40 = !DILocation(line: 14, column: 1, scope: !5)
!41 = !DILocation(line: 15, column: 1, scope: !5)
!42 = !DILocation(line: 16, column: 1, scope: !5)
!43 = !DILocation(line: 17, column: 1, scope: !5)
!44 = !DILocation(line: 18, column: 1, scope: !5)
!45 = !DILocation(line: 19, column: 1, scope: !5)
!46 = !DILocation(line: 20, column: 1, scope: !5)
;.
; CHECK: [[META9]] = !DILocalVariable(name: "1",
; CHECK: [[META11]] = !DILocalVariable(name: "2",
; CHECK: [[META12]] = !DILocalVariable(name: "3",
; CHECK: [[META14]] = !DILocalVariable(name: "4",
; CHECK: [[META15]] = !DILocalVariable(name: "5",
; CHECK: [[META16]] = !DILocalVariable(name: "6",
; CHECK: [[META17]] = !DILocalVariable(name: "7",
; CHECK: [[META18]] = !DILocalVariable(name: "8",
; CHECK: [[META19]] = !DILocalVariable(name: "9",
; CHECK: [[META20]] = !DILocalVariable(name: "10",
; CHECK: [[META21]] = !DILocalVariable(name: "11",
; CHECK: [[META22]] = !DILocalVariable(name: "12",
; CHECK: [[META23]] = !DILocalVariable(name: "13",
; CHECK: [[META24]] = !DILocalVariable(name: "14",
; CHECK: [[META25]] = !DILocalVariable(name: "15",
; CHECK: [[DBG28]] = !DILocation(line: 2, column: 1,
; CHECK: [[DBG29]] = !DILocation(line: 3, column: 1,
; CHECK: [[DBG30]] = !DILocation(line: 4, column: 1,
; CHECK: [[DBG31]] = !DILocation(line: 5, column: 1,
; CHECK: [[DBG33]] = !DILocation(line: 7, column: 1,
; CHECK: [[DBG34]] = !DILocation(line: 8, column: 1,
; CHECK: [[DBG35]] = !DILocation(line: 9, column: 1,
; CHECK: [[META37]] = !DILocation(line: 11, column: 1,
; CHECK: [[META39]] = !DILocation(line: 13, column: 1,
; CHECK: [[META40]] = !DILocation(line: 14, column: 1,
; CHECK: [[META41]] = !DILocation(line: 15, column: 1,
; CHECK: [[META42]] = !DILocation(line: 16, column: 1,
; CHECK: [[DBG43]] = !DILocation(line: 18, column: 1,
; CHECK: [[DBG44]] = !DILocation(line: 19, column: 1,
;.
Loading