From d7f6f1636d53c3e2faf55cdf20fbb44a1a149df1 Mon Sep 17 00:00:00 2001 From: Adrian Prantl Date: Tue, 28 Nov 2017 00:57:53 +0000 Subject: [PATCH] SROA: Avoid creating a fragment expression that covers the entire variable. Fixes PR35416. https://bugs.llvm.org/show_bug.cgi?id=35416 llvm-svn: 319126 --- llvm/lib/Transforms/Scalar/SROA.cpp | 13 ++- llvm/test/DebugInfo/Generic/sroa-samesize.ll | 114 +++++++++++++++++++++++++++ 2 files changed, 123 insertions(+), 4 deletions(-) create mode 100644 llvm/test/DebugInfo/Generic/sroa-samesize.ll diff --git a/llvm/lib/Transforms/Scalar/SROA.cpp b/llvm/lib/Transforms/Scalar/SROA.cpp index 8547960..9332107 100644 --- a/llvm/lib/Transforms/Scalar/SROA.cpp +++ b/llvm/lib/Transforms/Scalar/SROA.cpp @@ -4101,6 +4101,7 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) { if (!DbgDeclares.empty()) { auto *Var = DbgDeclares.front()->getVariable(); auto *Expr = DbgDeclares.front()->getExpression(); + auto VarSize = Var->getSizeInBits(); DIBuilder DIB(*AI.getModule(), /*AllowUnresolved*/ false); uint64_t AllocaSize = DL.getTypeSizeInBits(AI.getAllocatedType()); for (auto Fragment : Fragments) { @@ -4128,10 +4129,14 @@ bool SROA::splitAlloca(AllocaInst &AI, AllocaSlices &AS) { "new fragment is outside of original fragment"); Start -= OrigFragment->OffsetInBits; } - if (auto E = DIExpression::createFragmentExpression(Expr, Start, Size)) - FragmentExpr = *E; - else - continue; + // Avoid creating a fragment expression that covers the entire variable. + if (!VarSize || *VarSize != Size) { + if (auto E = + DIExpression::createFragmentExpression(Expr, Start, Size)) + FragmentExpr = *E; + else + continue; + } } // Remove any existing intrinsics describing the same alloca. diff --git a/llvm/test/DebugInfo/Generic/sroa-samesize.ll b/llvm/test/DebugInfo/Generic/sroa-samesize.ll new file mode 100644 index 0000000..8f3702b --- /dev/null +++ b/llvm/test/DebugInfo/Generic/sroa-samesize.ll @@ -0,0 +1,114 @@ +; RUN: opt -sroa -S -o - %s | FileCheck %s +; Generated from clang -c -O2 -g -target x86_64-pc-windows-msvc +; struct A { double x1[]; }; +; struct x2 { +; x2(int) : x3() {} +; int x3; +; }; +; int x4(); +; x2 x5() { +; x2 a(x4()); +; return a; +; } +; void *operator new(size_t, void *); +; struct B { +; B() { new (x8.x1) x2(x5()); } +; A x8; +; }; +; void x9() { B(); } +source_filename = "t.cpp" +target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-pc-windows-msvc19.11.0" + +%struct.B = type { %struct.A } +%struct.A = type { [0 x double], [8 x i8] } + +; Function Attrs: nounwind readnone speculatable +declare void @llvm.dbg.declare(metadata, metadata, metadata) #0 + +declare i32 @"\01?x4@@YAHXZ"() local_unnamed_addr + +define void @"\01?x9@@YAXXZ"() local_unnamed_addr !dbg !8 { +entry: + %agg.tmp.ensured = alloca %struct.B, align 8 + call void @llvm.dbg.declare(metadata %struct.B* %agg.tmp.ensured, metadata !11, metadata !DIExpression()), !dbg !24 + %call.i.i = call i32 @"\01?x4@@YAHXZ"(), !dbg !46, !noalias !47 + %x3.i.i.i = bitcast %struct.B* %agg.tmp.ensured to i32*, !dbg !50 + store i32 0, i32* %x3.i.i.i, align 4, !dbg !50, !tbaa !57, !alias.scope !47 + ; CHECK: call void @llvm.dbg.value(metadata i32 0, metadata ![[A:.*]], metadata !DIExpression()) + ; CHECK: ![[A]] = !DILocalVariable(name: "a", + ret void, !dbg !62 +} + +; Function Attrs: nounwind readnone speculatable +declare void @llvm.dbg.value(metadata, metadata, metadata) #0 + +attributes #0 = { nounwind readnone speculatable } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!3, !4, !5, !6} +!llvm.ident = !{!7} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 6.0.0 (trunk 319058) (llvm/trunk 319066)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "t.cpp", directory: "/") +!2 = !{} +!3 = !{i32 2, !"Dwarf Version", i32 4} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = !{i32 1, !"wchar_size", i32 2} +!6 = !{i32 7, !"PIC Level", i32 2} +!7 = !{!"clang version 6.0.0 (trunk 319058) (llvm/trunk 319066)"} +!8 = distinct !DISubprogram(name: "x9", linkageName: "\01?x9@@YAXXZ", scope: !1, file: !1, line: 16, type: !9, isLocal: false, isDefinition: true, scopeLine: 16, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !2) +!9 = !DISubroutineType(types: !10) +!10 = !{null} +!11 = !DILocalVariable(name: "a", scope: !12, file: !1, line: 8, type: !15) +!12 = distinct !DISubprogram(name: "x5", linkageName: "\01?x5@@YA?AUx2@@XZ", scope: !1, file: !1, line: 7, type: !13, isLocal: false, isDefinition: true, scopeLine: 7, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !23) +!13 = !DISubroutineType(types: !14) +!14 = !{!15} +!15 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "x2", file: !1, line: 2, size: 32, elements: !16, identifier: ".?AUx2@@") +!16 = !{!17, !19} +!17 = !DIDerivedType(tag: DW_TAG_member, name: "x3", scope: !15, file: !1, line: 4, baseType: !18, size: 32) +!18 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!19 = !DISubprogram(name: "x2", scope: !15, file: !1, line: 3, type: !20, isLocal: false, isDefinition: false, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true) +!20 = !DISubroutineType(types: !21) +!21 = !{null, !22, !18} +!22 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !15, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!23 = !{!11} +!24 = !DILocation(line: 8, column: 6, scope: !12, inlinedAt: !25) +!25 = distinct !DILocation(line: 13, column: 24, scope: !26, inlinedAt: !45) +!26 = distinct !DILexicalBlock(scope: !27, file: !1, line: 13, column: 7) +!27 = distinct !DISubprogram(name: "B", linkageName: "\01??0B@@QEAA@XZ", scope: !28, file: !1, line: 13, type: !39, isLocal: false, isDefinition: true, scopeLine: 13, flags: DIFlagPrototyped, isOptimized: true, unit: !0, declaration: !38, variables: !42) +!28 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "B", file: !1, line: 12, size: 64, elements: !29, identifier: ".?AUB@@") +!29 = !{!30, !38} +!30 = !DIDerivedType(tag: DW_TAG_member, name: "x8", scope: !28, file: !1, line: 14, baseType: !31, size: 64) +!31 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "A", file: !1, line: 1, size: 64, elements: !32, identifier: ".?AUA@@") +!32 = !{!33} +!33 = !DIDerivedType(tag: DW_TAG_member, name: "x1", scope: !31, file: !1, line: 1, baseType: !34) +!34 = !DICompositeType(tag: DW_TAG_array_type, baseType: !35, elements: !36) +!35 = !DIBasicType(name: "double", size: 64, encoding: DW_ATE_float) +!36 = !{!37} +!37 = !DISubrange(count: -1) +!38 = !DISubprogram(name: "B", scope: !28, file: !1, line: 13, type: !39, isLocal: false, isDefinition: false, scopeLine: 13, flags: DIFlagPrototyped, isOptimized: true) +!39 = !DISubroutineType(types: !40) +!40 = !{null, !41} +!41 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !28, size: 64, flags: DIFlagArtificial | DIFlagObjectPointer) +!42 = !{!43} +!43 = !DILocalVariable(name: "this", arg: 1, scope: !27, type: !44, flags: DIFlagArtificial | DIFlagObjectPointer) +!44 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !28, size: 64) +!45 = distinct !DILocation(line: 16, column: 13, scope: !8) +!46 = !DILocation(line: 8, column: 8, scope: !12, inlinedAt: !25) +!47 = !{!48} +!48 = distinct !{!48, !49, !"\01?x5@@YA?AUx2@@XZ: %agg.result"} +!49 = distinct !{!49, !"\01?x5@@YA?AUx2@@XZ"} +!50 = !DILocation(line: 3, column: 13, scope: !51, inlinedAt: !56) +!51 = distinct !DISubprogram(name: "x2", linkageName: "\01??0x2@@QEAA@H@Z", scope: !15, file: !1, line: 3, type: !20, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !0, declaration: !19, variables: !52) +!52 = !{!53, !54} +!53 = !DILocalVariable(arg: 2, scope: !51, file: !1, line: 3, type: !18) +!54 = !DILocalVariable(name: "this", arg: 1, scope: !51, type: !55, flags: DIFlagArtificial | DIFlagObjectPointer) +!55 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !15, size: 64) +!56 = distinct !DILocation(line: 8, column: 6, scope: !12, inlinedAt: !25) +!57 = !{!58, !59, i64 0} +!58 = !{!"?AUx2@@", !59, i64 0} +!59 = !{!"int", !60, i64 0} +!60 = !{!"omnipotent char", !61, i64 0} +!61 = !{!"Simple C++ TBAA"} +!62 = !DILocation(line: 16, column: 18, scope: !8) -- 2.7.4