Index: lib/Transforms/Scalar/EarlyCSE.cpp =================================================================== --- lib/Transforms/Scalar/EarlyCSE.cpp +++ lib/Transforms/Scalar/EarlyCSE.cpp @@ -717,6 +717,7 @@ // Dead instructions should just be removed. if (isInstructionTriviallyDead(Inst, &TLI)) { DEBUG(dbgs() << "EarlyCSE DCE: " << *Inst << '\n'); + salvageDebugInfo(*Inst); removeMSSA(Inst); Inst->eraseFromParent(); Changed = true; Index: test/Transforms/EarlyCSE/debuginfo-dce.ll =================================================================== --- /dev/null +++ test/Transforms/EarlyCSE/debuginfo-dce.ll @@ -0,0 +1,64 @@ +; RUN: opt -early-cse -S %s -o - | FileCheck %s +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" + +; Function Attrs: nounwind uwtable +define i32 @foo() !dbg !6 { +entry: + %0 = call i64 @llvm.ctpop.i64(i64 0), !dbg !14 + %1 = inttoptr i64 %0 to i32*, !dbg !14 + call void @llvm.dbg.value(metadata i32* %1, i64 0, metadata !11, metadata !13), !dbg !14 +; CHECK: call void @llvm.dbg.value(metadata i64 0, metadata !11, metadata !DIExpression()), !dbg !13 + %call = call i32* (...) @baa(), !dbg !15 + %2 = ptrtoint i32* %call to i64, !dbg !16 + %3 = inttoptr i64 %2 to i32*, !dbg !16 + call void @llvm.dbg.value(metadata i32* %3, i64 0, metadata !11, metadata !13), !dbg !14 + %tobool = icmp ne i32* %3, null, !dbg !17 + br i1 %tobool, label %if.end, label %if.then, !dbg !19 + +if.then: ; preds = %entry + br label %cleanup, !dbg !20 + +if.end: ; preds = %entry + %4 = ptrtoint i32* %3 to i32, !dbg !21 + br label %cleanup, !dbg !22 + +cleanup: ; preds = %if.end, %if.then + %retval.0 = phi i32 [ %4, %if.end ], [ 0, %if.then ] + ret i32 %retval.0, !dbg !22 +} + +declare i32* @baa(...) + +; Function Attrs: nounwind readnone +declare i64 @llvm.ctpop.i64(i64) + +; Function Attrs: nounwind readnone +declare void @llvm.dbg.value(metadata, i64, metadata, metadata) + +!llvm.dbg.cu = !{!0} +!llvm.module.flags = !{!3, !4} +!llvm.ident = !{!5} + +!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2) +!1 = !DIFile(filename: "test.c", directory: "/dir") +!2 = !{} +!3 = !{i32 2, !"Dwarf Version", i32 4} +!4 = !{i32 2, !"Debug Info Version", i32 3} +!5 = !{!"clang version 6.0.0"} +!6 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 3, type: !7, isLocal: false, isDefinition: true, scopeLine: 3, isOptimized: true, unit: !0, variables: !10) +!7 = !DISubroutineType(types: !8) +!8 = !{!9} +!9 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) +!10 = !{!11} +!11 = !DILocalVariable(name: "ptr", scope: !6, file: !1, line: 4, type: !12) +!12 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !9, size: 64) +!13 = !DIExpression() +!14 = !DILocation(line: 4, column: 8, scope: !6) +!15 = !DILocation(line: 5, column: 9, scope: !6) +!16 = !DILocation(line: 5, column: 7, scope: !6) +!17 = !DILocation(line: 7, column: 7, scope: !18) +!18 = distinct !DILexicalBlock(scope: !6, file: !1, line: 7, column: 6) +!19 = !DILocation(line: 7, column: 6, scope: !6) +!20 = !DILocation(line: 8, column: 5, scope: !18) +!21 = !DILocation(line: 10, column: 10, scope: !6) +!22 = !DILocation(line: 11, column: 1, scope: !6)