From 8d0ebfc10c4e3b36065f6e66fdfe03bc63a67e62 Mon Sep 17 00:00:00 2001 From: Orlando Cazalet-Hyams Date: Mon, 20 May 2019 09:40:44 +0000 Subject: [PATCH] [DebugInfo] Update loop metadata for inlined loops Summary: Currently, when a loop is cloned while inlining function (A) into function (B) the loop metadata is copied and then not modified at all. The loop metadata can encode the loop's start and end DILocations. Therefore, the new inlined loop in function (B) may have loop metadata which shows start and end locations residing in function (A). This patch ensures loop metadata is updated while inlining so that the start and end DILocations are given the "inlinedAt" operand. I've also added a regression test for this. This fix is required for D60831 because that patch uses loop metadata to determine the DILocation for the branches of new loop preheaders. Reviewers: aprantl, dblaikie, anemet Reviewed By: aprantl Subscribers: eraman, hiraditya, llvm-commits Tags: #debug-info, #llvm Differential Revision: https://reviews.llvm.org/D61933 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@361132 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Utils/InlineFunction.cpp | 51 ++++++++- .../Inline/inlined-loop-metadata.ll | 108 ++++++++++++++++++ 2 files changed, 156 insertions(+), 3 deletions(-) create mode 100755 test/Transforms/Inline/inlined-loop-metadata.ll diff --git a/lib/Transforms/Utils/InlineFunction.cpp b/lib/Transforms/Utils/InlineFunction.cpp index 6438d2d9f3b..9bcc043445c 100644 --- a/lib/Transforms/Utils/InlineFunction.cpp +++ b/lib/Transforms/Utils/InlineFunction.cpp @@ -1351,6 +1351,44 @@ static bool allocaWouldBeStaticInEntry(const AllocaInst *AI ) { return isa(AI->getArraySize()) && !AI->isUsedWithInAlloca(); } +/// Returns a DebugLoc for a new DILocation which is a clone of \p OrigDL +/// inlined at \p InlinedAt. \p IANodes is an inlined-at cache. +static DebugLoc inlineDebugLoc(DebugLoc OrigDL, DILocation *InlinedAt, + LLVMContext &Ctx, + DenseMap &IANodes) { + auto IA = DebugLoc::appendInlinedAt(OrigDL, InlinedAt, Ctx, IANodes); + return DebugLoc::get(OrigDL.getLine(), OrigDL.getCol(), OrigDL.getScope(), + IA); +} + +/// Returns the LoopID for a loop which has has been cloned from another +/// function for inlining with the new inlined-at start and end locs. +static MDNode *inlineLoopID(const MDNode *OrigLoopId, DILocation *InlinedAt, + LLVMContext &Ctx, + DenseMap &IANodes) { + assert(OrigLoopId && OrigLoopId->getNumOperands() > 0 && + "Loop ID needs at least one operand"); + assert(OrigLoopId && OrigLoopId->getOperand(0).get() == OrigLoopId && + "Loop ID should refer to itself"); + + // Save space for the self-referential LoopID. + SmallVector MDs = {nullptr}; + + for (unsigned i = 1; i < OrigLoopId->getNumOperands(); ++i) { + Metadata *MD = OrigLoopId->getOperand(i); + // Update the DILocations to encode the inlined-at metadata. + if (DILocation *DL = dyn_cast(MD)) + MDs.push_back(inlineDebugLoc(DL, InlinedAt, Ctx, IANodes)); + else + MDs.push_back(MD); + } + + MDNode *NewLoopID = MDNode::getDistinct(Ctx, MDs); + // Insert the self-referential LoopID. + NewLoopID->replaceOperandWith(0, NewLoopID); + return NewLoopID; +} + /// Update inlined instructions' line numbers to /// to encode location where these instructions are inlined. static void fixupLineNumbers(Function *Fn, Function::iterator FI, @@ -1376,10 +1414,17 @@ static void fixupLineNumbers(Function *Fn, Function::iterator FI, for (; FI != Fn->end(); ++FI) { for (BasicBlock::iterator BI = FI->begin(), BE = FI->end(); BI != BE; ++BI) { + // Loop metadata needs to be updated so that the start and end locs + // reference inlined-at locations. + if (MDNode *LoopID = BI->getMetadata(LLVMContext::MD_loop)) { + MDNode *NewLoopID = + inlineLoopID(LoopID, InlinedAtNode, BI->getContext(), IANodes); + BI->setMetadata(LLVMContext::MD_loop, NewLoopID); + } + if (DebugLoc DL = BI->getDebugLoc()) { - auto IA = DebugLoc::appendInlinedAt(DL, InlinedAtNode, BI->getContext(), - IANodes); - auto IDL = DebugLoc::get(DL.getLine(), DL.getCol(), DL.getScope(), IA); + DebugLoc IDL = + inlineDebugLoc(DL, InlinedAtNode, BI->getContext(), IANodes); BI->setDebugLoc(IDL); continue; } diff --git a/test/Transforms/Inline/inlined-loop-metadata.ll b/test/Transforms/Inline/inlined-loop-metadata.ll new file mode 100755 index 00000000000..ba99a6b8a59 --- /dev/null +++ b/test/Transforms/Inline/inlined-loop-metadata.ll @@ -0,0 +1,108 @@ +; This test checks that the !llvm.loop metadata has been updated after inlining +; so that the start and end locations refer to the inlined DILocations. + +; RUN: opt -loop-vectorize -inline %s -S 2>&1 | FileCheck %s +; CHECK: br i1 %{{.*}}, label %middle.block.i, label %vector.body.i, !dbg !{{[0-9]+}}, !llvm.loop [[VECTOR:![0-9]+]] +; CHECK: br i1 %{{.*}}, label %for.cond.cleanup.loopexit.i, label %for.body.i, !dbg !{{[0-9]+}}, !llvm.loop [[SCALAR:![0-9]+]] +; CHECK-DAG: [[VECTOR]] = distinct !{[[VECTOR]], [[START:![0-9]+]], [[END:![0-9]+]], [[IS_VECTORIZED:![0-9]+]]} +; CHECK-DAG: [[SCALAR]] = distinct !{[[SCALAR]], [[START]], [[END]], [[NO_UNROLL:![0-9]+]], [[IS_VECTORIZED]]} +; CHECK-DAG: [[IS_VECTORIZED]] = !{!"llvm.loop.isvectorized", i32 1} +; CHECK-DAG: [[NO_UNROLL]] = !{!"llvm.loop.unroll.runtime.disable"} + +; This IR can be generated by running: +; clang -emit-llvm -S -gmlt -O2 inlined.cpp -o before.ll -mllvm -opt-bisect-limit=53 +; +; Where inlined.cpp contains: +; extern int *Array; +; static int bar(unsigned x) +; { +; int Ret = 0; +; for (unsigned i = 0; i < x; ++i) +; { +; Ret += Array[i] * i; +; } +; return Ret; +; } +; +; int foo(unsigned x) +; { +; int Bar = bar(x); +; return Bar; +; } + +; ModuleID = 'inlined.cpp' +source_filename = "inlined.cpp" +target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-pc-windows-msvc19.16.27030" + +@"?Array@@3PEAHEA" = external dso_local local_unnamed_addr global i32*, align 8 + +; Function Attrs: nounwind uwtable +define dso_local i32 @"?foo@@YAHI@Z"(i32 %x) local_unnamed_addr !dbg !8 { +entry: + %call = call fastcc i32 @"?bar@@YAHI@Z"(i32 %x), !dbg !10 + ret i32 %call, !dbg !11 +} + +; Function Attrs: norecurse nounwind readonly uwtable +define internal fastcc i32 @"?bar@@YAHI@Z"(i32 %x) unnamed_addr !dbg !12 { +entry: + %cmp7 = icmp eq i32 %x, 0, !dbg !13 + br i1 %cmp7, label %for.cond.cleanup, label %for.body.lr.ph, !dbg !13 + +for.body.lr.ph: ; preds = %entry + %0 = load i32*, i32** @"?Array@@3PEAHEA", align 8, !dbg !14, !tbaa !15 + %wide.trip.count = zext i32 %x to i64, !dbg !14 + br label %for.body, !dbg !13 + +for.cond.cleanup.loopexit: ; preds = %for.body + %add.lcssa = phi i32 [ %add, %for.body ], !dbg !19 + br label %for.cond.cleanup, !dbg !20 + +for.cond.cleanup: ; preds = %for.cond.cleanup.loopexit, %entry + %Ret.0.lcssa = phi i32 [ 0, %entry ], [ %add.lcssa, %for.cond.cleanup.loopexit ], !dbg !14 + ret i32 %Ret.0.lcssa, !dbg !20 + +for.body: ; preds = %for.body, %for.body.lr.ph + %indvars.iv = phi i64 [ 0, %for.body.lr.ph ], [ %indvars.iv.next, %for.body ] + %Ret.08 = phi i32 [ 0, %for.body.lr.ph ], [ %add, %for.body ] + %arrayidx = getelementptr inbounds i32, i32* %0, i64 %indvars.iv, !dbg !19 + %1 = load i32, i32* %arrayidx, align 4, !dbg !19, !tbaa !21 + %2 = trunc i64 %indvars.iv to i32, !dbg !19 + %mul = mul i32 %1, %2, !dbg !19 + %add = add i32 %mul, %Ret.08, !dbg !19 + %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1, !dbg !13 + %exitcond = icmp eq i64 %indvars.iv.next, %wide.trip.count, !dbg !13 + br i1 %exitcond, label %for.cond.cleanup.loopexit, label %for.body, !dbg !13, !llvm.loop !23 +} + +!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 9.0.0 (https://github.com/llvm/llvm-project.git b1e28d9b6a16380ccf1456fe0695f639364407a9)", isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2, nameTableKind: None) +!1 = !DIFile(filename: "inlined.cpp", directory: "") +!2 = !{} +!3 = !{i32 2, !"CodeView", i32 1} +!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 9.0.0 (https://github.com/llvm/llvm-project.git b1e28d9b6a16380ccf1456fe0695f639364407a9)"} +!8 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 13, type: !9, scopeLine: 14, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2) +!9 = !DISubroutineType(types: !2) +!10 = !DILocation(line: 15, scope: !8) +!11 = !DILocation(line: 16, scope: !8) +!12 = distinct !DISubprogram(name: "bar", scope: !1, file: !1, line: 3, type: !9, scopeLine: 4, flags: DIFlagPrototyped, spFlags: DISPFlagLocalToUnit | DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !2) +!13 = !DILocation(line: 6, scope: !12) +!14 = !DILocation(line: 0, scope: !12) +!15 = !{!16, !16, i64 0} +!16 = !{!"any pointer", !17, i64 0} +!17 = !{!"omnipotent char", !18, i64 0} +!18 = !{!"Simple C++ TBAA"} +!19 = !DILocation(line: 8, scope: !12) +!20 = !DILocation(line: 10, scope: !12) +!21 = !{!22, !22, i64 0} +!22 = !{!"int", !17, i64 0} +!23 = distinct !{!23, !13, !24} +!24 = !DILocation(line: 9, scope: !12) + -- 2.50.1