1; RUN: opt -passes=instcombine -S %s -o - | FileCheck %s 2; RUN: opt -passes=instcombine -S %s -o - --try-experimental-debuginfo-iterators | FileCheck %s 3 4; In this example, the cast from ptr to ptr becomes trivially dead. We should 5; salvage its debug info. 6 7; C source: 8; void use_as_void(ptr); 9; void f(ptr p) { 10; int *q = (int *)p; 11; use_as_void(q); 12; } 13 14; ModuleID = '<stdin>' 15source_filename = "t.c" 16target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128" 17target triple = "x86_64-pc-windows-msvc19.11.25508" 18 19; Function Attrs: nounwind uwtable 20define void @f(ptr %p) !dbg !11 { 21entry: 22 call void @llvm.dbg.value(metadata ptr %p, metadata !16, metadata !DIExpression()), !dbg !18 23 call void @llvm.dbg.value(metadata ptr %p, metadata !17, metadata !DIExpression()), !dbg !20 24 call void @use_as_void(ptr %p), !dbg !22 25 ret void, !dbg !23 26} 27 28; CHECK-LABEL: define void @f(ptr %p) 29; CHECK: #dbg_value(ptr %p, ![[P_VAR:[0-9]+]], !DIExpression(), 30; CHECK-NOT: bitcast 31; CHECK: #dbg_value(ptr %p, ![[Q_VAR:[0-9]+]], !DIExpression(), 32; CHECK-NOT: bitcast 33; CHECK: ret void 34 35; CHECK: ![[P_VAR]] = !DILocalVariable(name: "p", {{.*}}) 36; CHECK: ![[Q_VAR]] = !DILocalVariable(name: "q", {{.*}}) 37 38declare void @use_as_void(ptr) 39 40declare void @llvm.dbg.value(metadata, metadata, metadata) 41 42!llvm.dbg.cu = !{!0} 43!llvm.module.flags = !{!6, !7, !8, !9} 44!llvm.ident = !{!10} 45 46!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3) 47!1 = !DIFile(filename: "t.c", directory: "C:\5Csrc\5Cllvm-project\5Cbuild", checksumkind: CSK_MD5, checksum: "56c40617ada23a8cccbd9a16bcec57af") 48!2 = !{} 49!3 = !{!4} 50!4 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !5, size: 64) 51!5 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) 52!6 = !{i32 2, !"CodeView", i32 1} 53!7 = !{i32 2, !"Debug Info Version", i32 3} 54!8 = !{i32 1, !"wchar_size", i32 2} 55!9 = !{i32 7, !"PIC Level", i32 2} 56!10 = !{!"clang version 6.0.0 "} 57!11 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 2, type: !12, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !15) 58!12 = !DISubroutineType(types: !13) 59!13 = !{null, !14} 60!14 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: null, size: 64) 61!15 = !{!16, !17} 62!16 = !DILocalVariable(name: "p", arg: 1, scope: !11, file: !1, line: 2, type: !14) 63!17 = !DILocalVariable(name: "q", scope: !11, file: !1, line: 3, type: !4) 64!18 = !DILocation(line: 2, column: 14, scope: !11) 65!19 = !DILocation(line: 3, column: 12, scope: !11) 66!20 = !DILocation(line: 3, column: 8, scope: !11) 67!21 = !DILocation(line: 4, column: 15, scope: !11) 68!22 = !DILocation(line: 4, column: 3, scope: !11) 69!23 = !DILocation(line: 5, column: 1, scope: !11) 70