Index: lib/Target/X86/X86CmovConversion.cpp =================================================================== --- lib/Target/X86/X86CmovConversion.cpp +++ lib/Target/X86/X86CmovConversion.cpp @@ -263,6 +263,9 @@ bool SkipGroup = false; for (auto &I : *MBB) { + // Skip DBG instructions. + if (I.isDebugValue()) + continue; X86::CondCode CC = X86::getCondFromCMovOpc(I.getOpcode()); // Check if we found a X86::CMOVrr instruction. if (CC != X86::COND_INVALID && (IncludeLoads || !I.mayLoad())) { @@ -400,6 +403,9 @@ // Clear physical registers Def map. RegDefMaps[PhyRegType].clear(); for (MachineInstr &MI : *MBB) { + // Skip DBG instructions. + if (MI.isDebugValue()) + continue; unsigned MIDepth = 0; unsigned MIDepthOpt = 0; bool IsCMOV = CmovInstructions.count(&MI); @@ -612,6 +618,17 @@ MachineFunction *F = MBB->getParent(); const BasicBlock *BB = MBB->getBasicBlock(); + // If there are DBG instructions between first CMOV and last CMOV, move them + // to after the last CMOV. + MachineBasicBlock::iterator DbgIt = MI.getIterator(); + MachineBasicBlock::iterator DbgE = LastCMOV->getIterator(); + while (DbgIt != DbgE) { + MachineInstr &I = *DbgIt++; + if (I.isDebugValue()) { + MBB->insertAfter(DbgE, I.removeFromParent()); + } + } + MachineBasicBlock *FalseMBB = F->CreateMachineBasicBlock(BB); MachineBasicBlock *SinkMBB = F->CreateMachineBasicBlock(BB); F->insert(It, FalseMBB); Index: test/CodeGen/X86/PR34565.ll =================================================================== --- test/CodeGen/X86/PR34565.ll +++ test/CodeGen/X86/PR34565.ll @@ -0,0 +1,60 @@ +; RUN: llc -mtriple=x86_64-pc-linux -x86-cmov-converter=true -verify-machineinstrs < %s | FileCheck %s + +; Test for PR34565, check that DBG instructions are ignored while optimizing +; X86 CMOV instructions. +; In this case, we check that there is no 'cmov' generated. + +; CHECK-NOT: cmov + +@main.buf = private unnamed_addr constant [10 x i64] [i64 0, i64 1, i64 2, i64 3, i64 4, i64 5, i64 6, i64 7, i64 8, i64 9], align 8 + +define i32 @main() #0 !dbg !5 { +entry: + br label %while.body + +while.body: ; preds = %while.body, %entry + %a.010 = phi i32 [ 0, %entry ], [ %add.a.0, %while.body ] + %b.09 = phi i32 [ 10, %entry ], [ %b.0.add, %while.body ] + %add = add i32 %a.010, %b.09 + %call = tail call i32 @rand() + %conv = sext i32 %call to i64 + %arrayidx = getelementptr inbounds [10 x i64], [10 x i64]* @main.buf, i32 0, i32 %add + %0 = load i64, i64* %arrayidx, align 8 + %cmp1 = icmp ult i64 %0, %conv + %b.0.add = select i1 %cmp1, i32 %b.09, i32 %add + %add.a.0 = select i1 %cmp1, i32 %add, i32 %a.010 + tail call void @llvm.dbg.value(metadata i32 %add.a.0, metadata !10, metadata !DIExpression()), !dbg !13 + tail call void @llvm.dbg.value(metadata i32 %b.0.add, metadata !12, metadata !DIExpression()), !dbg !14 + tail call void @llvm.dbg.value(metadata i32 %add.a.0, metadata !10, metadata !DIExpression()), !dbg !13 + tail call void @llvm.dbg.value(metadata i32 %b.0.add, metadata !12, metadata !DIExpression()), !dbg !14 + %cmp = icmp ult i32 %add.a.0, %b.0.add + br i1 %cmp, label %while.body, label %while.end + +while.end: ; preds = %while.body + ret i32 0 +} + +declare i32 @rand() + +declare void @llvm.dbg.value(metadata, metadata, metadata) + +attributes #0 = { "target-cpu"="x86-64" } + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!3, !4} + +!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0 (trunk)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "PR34565.c", directory: "\5C") +!2 = !{} +!3 = !{i32 2, !"Dwarf Version", i32 4} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 3, type: !6, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !9) +!6 = !DISubroutineType(types: !7) +!7 = !{!8} +!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!9 = !{!10, !12} +!10 = !DILocalVariable(name: "a", scope: !5, file: !1, line: 6, type: !11) +!11 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned) +!12 = !DILocalVariable(name: "b", scope: !5, file: !1, line: 7, type: !11) +!13 = !DILocation(line: 6, column: 16, scope: !5) +!14 = !DILocation(line: 7, column: 16, scope: !5)