diff options
| -rw-r--r-- | llvm/lib/Transforms/Scalar/Reassociate.cpp | 13 | ||||
| -rw-r--r-- | llvm/test/Transforms/Reassociate/reassociate_dbgvalue_discard.ll | 79 |
2 files changed, 92 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Scalar/Reassociate.cpp b/llvm/lib/Transforms/Scalar/Reassociate.cpp index 0317025e5d2..36f16618a75 100644 --- a/llvm/lib/Transforms/Scalar/Reassociate.cpp +++ b/llvm/lib/Transforms/Scalar/Reassociate.cpp @@ -43,6 +43,7 @@ #include "llvm/IR/InstrTypes.h" #include "llvm/IR/Instruction.h" #include "llvm/IR/Instructions.h" +#include "llvm/IR/IntrinsicInst.h" #include "llvm/IR/Operator.h" #include "llvm/IR/PassManager.h" #include "llvm/IR/PatternMatch.h" @@ -780,6 +781,18 @@ void ReassociatePass::RewriteExprTree(BinaryOperator *I, if (ExpressionChanged == I) break; + + // Discard any debug info related to the expressions that has changed (we + // can leave debug infor related to the root, since the result of the + // expression tree should be the same even after reassociation). + SmallVector<DbgInfoIntrinsic *, 1> DbgUsers; + findDbgUsers(DbgUsers, ExpressionChanged); + for (auto *DII : DbgUsers) { + Value *Undef = UndefValue::get(ExpressionChanged->getType()); + DII->setOperand(0, MetadataAsValue::get(DII->getContext(), + ValueAsMetadata::get(Undef))); + } + ExpressionChanged->moveBefore(I); ExpressionChanged = cast<BinaryOperator>(*ExpressionChanged->user_begin()); } while (true); diff --git a/llvm/test/Transforms/Reassociate/reassociate_dbgvalue_discard.ll b/llvm/test/Transforms/Reassociate/reassociate_dbgvalue_discard.ll new file mode 100644 index 00000000000..59f1d4890e6 --- /dev/null +++ b/llvm/test/Transforms/Reassociate/reassociate_dbgvalue_discard.ll @@ -0,0 +1,79 @@ +; NOTE: Assertions have been autogenerated by utils/update_test_checks.py +; RUN: opt < %s -reassociate -S -o - | FileCheck %s + +; After reassociation m1 and m2 aren't calculated as m1=c*a and m2=c*b any longer. +; So let's verify that the dbg.value nodes for m1 and m3 are invalidated. + +source_filename = "reassociate_dbgvalue_discard.c" +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define dso_local i32 @test1(i32 %a, i32 %b, i32 %c, i32 %d) local_unnamed_addr #0 !dbg !7 { +; CHECK-LABEL: @test1( +; CHECK-NEXT: entry: +; CHECK-NEXT: call void @llvm.dbg.value(metadata i32 undef, metadata !16, metadata !DIExpression()), !dbg !20 +; CHECK-NEXT: call void @llvm.dbg.value(metadata i32 undef, metadata !17, metadata !DIExpression()), !dbg !21 +; CHECK-NEXT: [[M1:%.*]] = mul i32 [[D:%.*]], [[C:%.*]], !dbg !22 +; CHECK-NEXT: [[M3:%.*]] = mul i32 [[M1]], [[A:%.*]], !dbg !23 +; CHECK-NEXT: call void @llvm.dbg.value(metadata i32 [[M3]], metadata !18, metadata !DIExpression()), !dbg !24 +; CHECK-NEXT: [[M2:%.*]] = mul i32 [[D]], [[C]], !dbg !25 +; CHECK-NEXT: [[M4:%.*]] = mul i32 [[M2]], [[B:%.*]], !dbg !26 +; CHECK-NEXT: call void @llvm.dbg.value(metadata i32 [[M4]], metadata !19, metadata !DIExpression()), !dbg !27 +; CHECK-NEXT: [[RES:%.*]] = xor i32 [[M3]], [[M4]] +; CHECK-NEXT: ret i32 [[RES]], !dbg !28 +; +entry: + %m1 = mul i32 %c, %a, !dbg !24 + call void @llvm.dbg.value(metadata i32 %m1, metadata !16, metadata !DIExpression()), !dbg !25 + %m2 = mul i32 %c, %b, !dbg !26 + call void @llvm.dbg.value(metadata i32 %m2, metadata !17, metadata !DIExpression()), !dbg !27 + %m3 = mul i32 %m1, %d, !dbg !28 + call void @llvm.dbg.value(metadata i32 %m3, metadata !18, metadata !DIExpression()), !dbg !29 + %m4 = mul i32 %m2, %d, !dbg !30 + call void @llvm.dbg.value(metadata i32 %m4, metadata !19, metadata !DIExpression()), !dbg !31 + %res = xor i32 %m3, %m4 + ret i32 %res, !dbg !32 +} + +declare void @llvm.dbg.value(metadata, metadata, metadata) #1 + +attributes #0 = { nounwind readnone uwtable } +attributes #1 = { nounwind readnone speculatable } + +!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 7.0.0 (trunk 330596) (llvm/trunk 330594)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "reassociate_dbgvalue_discard.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 7.0.0 (trunk 330596) (llvm/trunk 330594)"} +!7 = distinct !DISubprogram(name: "test1", scope: !1, file: !1, line: 3, type: !8, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !11) +!8 = !DISubroutineType(types: !9) +!9 = !{!10, !10, !10, !10, !10} +!10 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!11 = !{!12, !13, !14, !15, !16, !17, !18, !19} +!12 = !DILocalVariable(name: "a", arg: 1, scope: !7, file: !1, line: 3, type: !10) +!13 = !DILocalVariable(name: "b", arg: 2, scope: !7, file: !1, line: 3, type: !10) +!14 = !DILocalVariable(name: "c", arg: 3, scope: !7, file: !1, line: 3, type: !10) +!15 = !DILocalVariable(name: "d", arg: 4, scope: !7, file: !1, line: 3, type: !10) +!16 = !DILocalVariable(name: "t1", scope: !7, file: !1, line: 4, type: !10) +!17 = !DILocalVariable(name: "t2", scope: !7, file: !1, line: 5, type: !10) +!18 = !DILocalVariable(name: "t3", scope: !7, file: !1, line: 6, type: !10) +!19 = !DILocalVariable(name: "t4", scope: !7, file: !1, line: 7, type: !10) +!20 = !DILocation(line: 3, column: 15, scope: !7) +!21 = !DILocation(line: 3, column: 22, scope: !7) +!22 = !DILocation(line: 3, column: 29, scope: !7) +!23 = !DILocation(line: 3, column: 36, scope: !7) +!24 = !DILocation(line: 4, column: 14, scope: !7) +!25 = !DILocation(line: 4, column: 7, scope: !7) +!26 = !DILocation(line: 5, column: 14, scope: !7) +!27 = !DILocation(line: 5, column: 7, scope: !7) +!28 = !DILocation(line: 6, column: 15, scope: !7) +!29 = !DILocation(line: 6, column: 7, scope: !7) +!30 = !DILocation(line: 7, column: 15, scope: !7) +!31 = !DILocation(line: 7, column: 7, scope: !7) +!32 = !DILocation(line: 8, column: 3, scope: !7) |
