; RUN: opt %s -S -passes=dse -o - | FileCheck %s --implicit-check-not="call void @llvm.dbg" ; RUN: opt --try-experimental-debuginfo-iterators %s -S -passes=dse -o - | FileCheck %s --implicit-check-not="call void @llvm.dbg" ;; Based on the test shorten.ll with some adjustments. ;; ;; $ cat test.cpp ;; void esc(char*); ;; void shortenEnd() { ;; char local[80]; // bits frag ;; __builtin_memset(local + 8, 0, 24); // local: 64-160 ( 64, 96) ;; __builtin_memset(local + 16, 8, 40); // local: 128-160 (128, 32) ;; esc(local); ;; } ;; void shortenStart() { ;; char local2[40]; // bits frag ;; __builtin_memset(local2, 0, 40); // local2: 0-160 (0, 160) ;; __builtin_memset(local2, 8, 16); // local2: 0-128 (0, 128) ;; esc(local2); ;; } ;; The variables and intrinsics have been adjusted with by hand to test ;; what happens when the variable doesn't fill the whole alloca, and ;; when offsets are encoded with both the address component of the dbg.assign ;; and the address modifying DIExpression. ;; DeadStoreElimination will shorten the first store in shortenEnd from [64, ;; 192) bits to [64, 128) bits. Variable 'local' has been adjusted to be 160 ;; bits large. Check that we get an unlinked dbg.assign covering the deleted ;; bits that overlap the dbg.assign's fagment: [128, 160) (offset=128 size=32). ; CHECK: @_Z10shortenEndv ; CHECK: #dbg_assign({{.*}}, ptr %local, !DIExpression(), ; CHECK: call void @llvm.memset{{.*}}, !DIAssignID ![[ID:[0-9]+]] ; CHECK-NEXT: #dbg_assign(i8 0, ![[VAR:[0-9]+]], !DIExpression(DW_OP_LLVM_fragment, 64, 96), ![[ID:[0-9]+]], ptr %offset_4_bytes, !DIExpression(DW_OP_plus_uconst, 4), ; CHECK-NEXT: #dbg_assign(i8 0, ![[VAR]], !DIExpression(DW_OP_LLVM_fragment, 128, 32), ![[UniqueID1:[0-9]+]], ptr poison, !DIExpression({{.*}}), ;; DSE will shorten the first store in shortenStart from [0, 160) bits to [128, ;; 160) bits. Variable 'local2' has been adjusted to be 160 bits. Check we get ;; an unlinked dbg.assign covering the deleted bits that overlap the ;; dbg.assign's fragment (no fragment in this case, i.e. the whole variable): ;; [0, 128) (offset=0, size=128). ; CHECK: @_Z12shortenStartv ; CHECK: #dbg_assign({{.*}}, ptr %local2, !DIExpression(), ; CHECK: call void @llvm.memset{{.*}}, !DIAssignID ![[ID2:[0-9]+]] ; CHECK-NEXT: #dbg_assign(i8 0, ![[VAR2:[0-9]+]], !DIExpression(), ![[ID2]], ptr %local2, !DIExpression(), ; CHECK-NEXT: #dbg_assign(i8 0, ![[VAR2]], !DIExpression(DW_OP_LLVM_fragment, 0, 128), ![[UniqueID2:[0-9]+]], ptr poison, !DIExpression(), ; CHECK-DAG: ![[ID]] = distinct !DIAssignID() ; CHECK-DAG: ![[UniqueID1]] = distinct !DIAssignID() ; CHECK-DAG: ![[UniqueID2]] = distinct !DIAssignID() define dso_local void @_Z10shortenEndv() local_unnamed_addr #0 !dbg !7 { entry: %local = alloca [80 x i8], align 16, !DIAssignID !16 call void @llvm.dbg.assign(metadata i1 poison, metadata !11, metadata !DIExpression(), metadata !16, metadata ptr %local, metadata !DIExpression()), !dbg !17 %arraydecay = getelementptr inbounds [80 x i8], ptr %local, i64 0, i64 0, !dbg !19 %offset_4_bytes = getelementptr inbounds [80 x i8], ptr %local, i64 0, i64 4, !dbg !21 %offset_8_bytes = getelementptr inbounds [80 x i8], ptr %local, i64 0, i64 8, !dbg !21 call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(24) %offset_8_bytes, i8 0, i64 72, i1 false), !dbg !19, !DIAssignID !20 call void @llvm.dbg.assign(metadata i8 0, metadata !11, metadata !DIExpression(DW_OP_LLVM_fragment, 64, 96), metadata !20, metadata ptr %offset_4_bytes, metadata !DIExpression(DW_OP_plus_uconst, 4)), !dbg !17 %offset_16_bytes = getelementptr inbounds [80 x i8], ptr %local, i64 0, i64 4, !dbg !21 call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(40) %offset_16_bytes, i8 8, i64 64, i1 false), !dbg !22, !DIAssignID !23 call void @_Z3escPi(ptr noundef nonnull %arraydecay), !dbg !24 ret void, !dbg !25 } declare void @llvm.memset.p0.i64(ptr nocapture writeonly, i8, i64, i1 immarg) declare !dbg !26 dso_local void @_Z3escPi(ptr noundef) local_unnamed_addr define dso_local void @_Z12shortenStartv() local_unnamed_addr #0 !dbg !31 { entry: %local2 = alloca [40 x i8], align 16, !DIAssignID !37 call void @llvm.dbg.assign(metadata i1 poison, metadata !33, metadata !DIExpression(), metadata !37, metadata ptr %local2, metadata !DIExpression()), !dbg !38 %arraydecay = getelementptr inbounds [40 x i8], ptr %local2, i64 0, i64 0, !dbg !40 call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(40) %local2, i8 0, i64 36, i1 false), !dbg !40, !DIAssignID !41 call void @llvm.dbg.assign(metadata i8 0, metadata !33, metadata !DIExpression(), metadata !41, metadata ptr %local2, metadata !DIExpression()), !dbg !38 call void @llvm.memset.p0.i64(ptr noundef nonnull align 16 dereferenceable(16) %local2, i8 8, i64 16, i1 false), !dbg !42, !DIAssignID !43 call void @_Z3escPi(ptr noundef nonnull %arraydecay), !dbg !44 ret void, !dbg !45 } declare void @llvm.dbg.assign(metadata, metadata, metadata, metadata, metadata, metadata) !llvm.dbg.cu = !{!0} !llvm.module.flags = !{!2, !3, !4, !5, !1000} !llvm.ident = !{!6} !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 14.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None) !1 = !DIFile(filename: "test.cpp", directory: "/") !2 = !{i32 7, !"Dwarf Version", i32 5} !3 = !{i32 2, !"Debug Info Version", i32 3} !4 = !{i32 1, !"wchar_size", i32 4} !5 = !{i32 7, !"uwtable", i32 1} !6 = !{!"clang version 14.0.0"} !7 = distinct !DISubprogram(name: "shortenEnd", linkageName: "_Z10shortenEndv", scope: !1, file: !1, line: 2, type: !8, scopeLine: 2, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !10) !8 = !DISubroutineType(types: !9) !9 = !{null} !10 = !{!11} !11 = !DILocalVariable(name: "local", scope: !7, file: !1, line: 3, type: !12) !12 = !DICompositeType(tag: DW_TAG_array_type, baseType: !13, size: 160, elements: !14) !13 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed) !14 = !{!15} !15 = !DISubrange(count: 5) !16 = distinct !DIAssignID() !17 = !DILocation(line: 0, scope: !7) !18 = !DILocation(line: 3, column: 3, scope: !7) !19 = !DILocation(line: 4, column: 3, scope: !7) !20 = distinct !DIAssignID() !21 = !DILocation(line: 5, column: 26, scope: !7) !22 = !DILocation(line: 5, column: 3, scope: !7) !23 = distinct !DIAssignID() !24 = !DILocation(line: 6, column: 3, scope: !7) !25 = !DILocation(line: 7, column: 1, scope: !7) !26 = !DISubprogram(name: "esc", linkageName: "_Z3escPi", scope: !1, file: !1, line: 1, type: !27, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !30) !27 = !DISubroutineType(types: !28) !28 = !{null, !29} !29 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !13, size: 64) !30 = !{} !31 = distinct !DISubprogram(name: "shortenStart", linkageName: "_Z12shortenStartv", scope: !1, file: !1, line: 8, type: !8, scopeLine: 8, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !32) !32 = !{!33} !33 = !DILocalVariable(name: "local2", scope: !31, file: !1, line: 9, type: !34) !34 = !DICompositeType(tag: DW_TAG_array_type, baseType: !13, size: 160, elements: !35) !35 = !{!36} !36 = !DISubrange(count: 5) !37 = distinct !DIAssignID() !38 = !DILocation(line: 0, scope: !31) !39 = !DILocation(line: 9, column: 3, scope: !31) !40 = !DILocation(line: 10, column: 3, scope: !31) !41 = distinct !DIAssignID() !42 = !DILocation(line: 11, column: 3, scope: !31) !43 = distinct !DIAssignID() !44 = !DILocation(line: 12, column: 3, scope: !31) !45 = !DILocation(line: 13, column: 1, scope: !31) !1000 = !{i32 7, !"debug-info-assignment-tracking", i1 true}