1; RUN: opt -S -passes=dse -dse-memoryssa-scanlimit=2 < %s | FileCheck %s 2; RUN: opt -S -strip-debug -passes=dse -dse-memoryssa-scanlimit=2 < %s | FileCheck %s 3 4; Test case to check that DSE gets the same result even if we have a dbg value 5; between the memcpy. 6 7; This test case is less relevant for the MemorySSA backed version of DSE, as 8; debug values are not modeled in MemorySSA and are skipped regardless of the 9; exploration limit. 10 11target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" 12target triple = "x86_64-unknown-linux-gnu" 13 14@g = common global [1 x i8] zeroinitializer, align 1, !dbg !0 15 16; Function Attrs: noinline nounwind uwtable 17define void @foo() #0 !dbg !14 { 18entry: 19 %i = alloca i8, align 1 20 store i8 1, ptr %i, align 1, !dbg !19 21 call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 22 call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 23 call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 24 call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 25 call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 26 call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 27 call void @llvm.memcpy.p0.p0.i64(ptr %i, ptr @g, i64 1, i1 false), !dbg !20 28 br label %bb2 29 30bb2: ; preds = @g 31 ret void, !dbg !21 32} 33 34; Function Attrs: nounwind readnone speculatable 35declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1 36 37; Function Attrs: argmemonly nounwind 38declare void @llvm.memcpy.p0.p0.i64(ptr nocapture writeonly, ptr nocapture readonly, i64, i1) #2 39 40attributes #0 = { noinline nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "frame-pointer"="all" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="x86-64" "target-features"="+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" } 41attributes #1 = { nounwind readnone speculatable } 42attributes #2 = { argmemonly nounwind } 43 44!llvm.dbg.cu = !{!2} 45!llvm.module.flags = !{!10, !11, !12} 46!llvm.ident = !{!13} 47 48!0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) 49!1 = distinct !DIGlobalVariable(name: "g", scope: !2, file: !3, line: 3, type: !6, isLocal: false, isDefinition: true) 50!2 = distinct !DICompileUnit(language: DW_LANG_C99, file: !3, producer: "clang version 6.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !4, globals: !5) 51!3 = !DIFile(filename: "foo.c", directory: "/bar") 52!4 = !{} 53!5 = !{!0} 54!6 = !DICompositeType(tag: DW_TAG_array_type, baseType: !7, size: 8, elements: !8) 55!7 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) 56!8 = !{!9} 57!9 = !DISubrange(count: 1) 58!10 = !{i32 2, !"Dwarf Version", i32 4} 59!11 = !{i32 2, !"Debug Info Version", i32 3} 60!12 = !{i32 1, !"wchar_size", i32 4} 61!13 = !{!"clang version 6.0.0"} 62!14 = distinct !DISubprogram(name: "foo", scope: !3, file: !3, line: 5, type: !15, isLocal: false, isDefinition: true, scopeLine: 6, isOptimized: false, unit: !2, retainedNodes: !4) 63!15 = !DISubroutineType(types: !16) 64!16 = !{null} 65!17 = !DILocalVariable(name: "i", scope: !14, file: !3, line: 7, type: !7) 66!18 = !DILocation(line: 7, column: 10, scope: !14) 67!19 = !DILocation(line: 8, column: 7, scope: !14) 68!20 = !DILocation(line: 9, column: 5, scope: !14) 69!21 = !DILocation(line: 10, column: 1, scope: !14) 70 71; Check that the both the store and memcpy are removed because they both access 72; an alloca that is not read. 73; CHECK-LABEL: foo 74; CHECK-NOT: store i8 75; CHECK-NOT: call void @llvm.memcpy 76; CHECK: ret void 77