From a6df1e57e873c4720a00c02de3a25b07596e5243 Mon Sep 17 00:00:00 2001 From: Wolfgang Pieb Date: Wed, 19 Jul 2017 19:36:40 +0000 Subject: [PATCH] Fixing an issue with the initialization of LexicalScopes objects when mixing debug and non-debug units. Patch by Andrea DiBiagio. Differential Revision: https://reviews.llvm.org/D35637 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@308513 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/CodeGen/LexicalScopes.cpp | 5 +- lib/CodeGen/LiveDebugValues.cpp | 7 ++- test/CodeGen/X86/debug-nodebug-crash.ll | 61 +++++++++++++++++++++++++ 3 files changed, 71 insertions(+), 2 deletions(-) create mode 100644 test/CodeGen/X86/debug-nodebug-crash.ll diff --git a/lib/CodeGen/LexicalScopes.cpp b/lib/CodeGen/LexicalScopes.cpp index 995c58a6356..47ab4ef65c7 100644 --- a/lib/CodeGen/LexicalScopes.cpp +++ b/lib/CodeGen/LexicalScopes.cpp @@ -47,11 +47,11 @@ void LexicalScopes::reset() { /// initialize - Scan machine function and constuct lexical scope nest. void LexicalScopes::initialize(const MachineFunction &Fn) { + reset(); // Don't attempt any lexical scope creation for a NoDebug compile unit. if (Fn.getFunction()->getSubprogram()->getUnit()->getEmissionKind() == DICompileUnit::NoDebug) return; - reset(); MF = &Fn; SmallVector MIRanges; DenseMap MI2ScopeMap; @@ -277,7 +277,9 @@ void LexicalScopes::assignInstructionRanges( /// DebugLoc. void LexicalScopes::getMachineBasicBlocks( const DILocation *DL, SmallPtrSetImpl &MBBs) { + assert(MF && "Method called on a uninitialized LexicalScopes object!"); MBBs.clear(); + LexicalScope *Scope = getOrCreateLexicalScope(DL); if (!Scope) return; @@ -296,6 +298,7 @@ void LexicalScopes::getMachineBasicBlocks( /// dominates - Return true if DebugLoc's lexical scope dominates at least one /// machine instruction's lexical scope in a given machine basic block. bool LexicalScopes::dominates(const DILocation *DL, MachineBasicBlock *MBB) { + assert(MF && "Unexpected uninitialized LexicalScopes object!"); LexicalScope *Scope = getOrCreateLexicalScope(DL); if (!Scope) return false; diff --git a/lib/CodeGen/LiveDebugValues.cpp b/lib/CodeGen/LiveDebugValues.cpp index b5e705f6455..4614ddce5e0 100644 --- a/lib/CodeGen/LiveDebugValues.cpp +++ b/lib/CodeGen/LiveDebugValues.cpp @@ -1,4 +1,4 @@ -//===------ LiveDebugValues.cpp - Tracking Debug Value MIs ----------------===// +//===------ LiveDebugValues.cpp - Tracking Debug Value MIs ----------------===//G // // The LLVM Compiler Infrastructure // @@ -702,6 +702,11 @@ bool LiveDebugValues::runOnMachineFunction(MachineFunction &MF) { // LiveDebugValues will already have removed all DBG_VALUEs. return false; + // Skip functions from NoDebug compilation units. + if (MF.getFunction()->getSubprogram()->getUnit()->getEmissionKind() == + DICompileUnit::NoDebug) + return false; + TRI = MF.getSubtarget().getRegisterInfo(); TII = MF.getSubtarget().getInstrInfo(); TFI = MF.getSubtarget().getFrameLowering(); diff --git a/test/CodeGen/X86/debug-nodebug-crash.ll b/test/CodeGen/X86/debug-nodebug-crash.ll new file mode 100644 index 00000000000..44512e773c6 --- /dev/null +++ b/test/CodeGen/X86/debug-nodebug-crash.ll @@ -0,0 +1,61 @@ +;RUN: llc < %s | FileCheck %s +; +; LexicalScope objects were not cleared when a nodebug function is handled in +; LiveDebugValues. This may lead to an assertion in the constructor for LexicalScope, +; triggered by LiveDebugValues when another (debug) function is handled later. +; +; This minimal example does not leave much to check for, so we just make sure we get +; reasonable output, preserving function labels and a DBG_VALUE comment. +; +; CHECK-LABEL: foo: +; CHECK-NEXT: Lfunc_begin0: +; CHECK: Lfunc_end0: +; CHECK-LABEL: bar: +; CHECK-NEXT: Lfunc_begin1: +; CHECK: #DEBUG_VALUE: foo:x <- +; CHECK: Lfunc_end1: + +define i32 @foo() { +entry: + ret i32 0 +} + +define i32 @bar(i32 %x) !dbg !50 { +entry: + tail call void @llvm.dbg.value(metadata i32 %x, i64 0, metadata !41, metadata !43), !dbg !52 + %tobool.i = icmp eq i32 %x, 0 + br i1 %tobool.i, label %foo.exit, label %if.then.i + +if.then.i: + br label %foo.exit + +foo.exit: + %x.addr.0.i = phi i32 [ 1, %if.then.i ], [ 0, %entry ] + ret i32 %x.addr.0.i +} + +declare void @llvm.dbg.value(metadata, i64, metadata, metadata) + +!llvm.dbg.cu = !{!0, !3} +!llvm.ident = !{!5, !5} +!llvm.module.flags = !{!6, !7} + +!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "foo.cpp", directory: "c:\temp") +!2 = !{} +!3 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !4, producer: "", isOptimized: true, runtimeVersion: 0, emissionKind: NoDebug, enums: !2) +!4 = !DIFile(filename: "bar.cpp", directory: "c:\temp") +!5 = !{!"clang version 4.0.0"} +!6 = !{i32 2, !"Dwarf Version", i32 4} +!7 = !{i32 2, !"Debug Info Version", i32 3} +!36 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 1, type: !37, isLocal: false, isDefinition: true, scopeLine: 1, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !40) +!37 = !DISubroutineType(types: !38) +!38 = !{!39, !39} +!39 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!40 = !{!41} +!41 = !DILocalVariable(name: "x", arg: 1, scope: !36, file: !1, line: 1, type: !39) +!43 = !DIExpression() +!50 = distinct !DISubprogram(name: "bar", scope: !4, file: !4, line: 3, type: !51, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !3, variables: !2) +!51 = !DISubroutineType(types: !2) +!52 = !DILocation(line: 1, scope: !36, inlinedAt: !53) +!53 = distinct !DILocation(line: 5, scope: !50) -- 2.40.0