| ; RUN: opt -S -dse -dse-memoryssa-scanlimit=2 < %s | FileCheck %s |
| ; RUN: opt -S -strip-debug -dse -dse-memoryssa-scanlimit=2 < %s | FileCheck %s |
| |
| ; Test case to check that DSE gets the same result even if we have a dbg value |
| ; between the memcpy. |
| |
| ; This test case is less relevant for the MemorySSA backed version of DSE, as |
| ; debug values are not modeled in MemorySSA and are skipped regardless of the |
| ; exploration limit. |
| |
| target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" |
| target triple = "x86_64-unknown-linux-gnu" |
| |
| @g = common global [1 x i8] zeroinitializer, align 1, !dbg !0 |
| |
| ; Function Attrs: noinline nounwind uwtable |
| define void @foo() #0 !dbg !14 { |
| entry: |
| %i = alloca i8, align 1 |
| store i8 1, i8* %i, align 1, !dbg !19 |
| call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 |
| call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 |
| call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 |
| call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 |
| call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 |
| call void @llvm.dbg.value(metadata i32 0, i64 0, metadata !17, metadata !DIExpression()), !dbg !18 |
| %0 = bitcast [1 x i8]* @g to i8* |
| call void @llvm.memcpy.p0i8.p0i8.i64(i8* %i, i8* %0, i64 1, i1 false), !dbg !20 |
| br label %bb2 |
| |
| bb2: ; preds = %0 |
| ret void, !dbg !21 |
| } |
| |
| ; Function Attrs: nounwind readnone speculatable |
| declare void @llvm.dbg.value(metadata, i64, metadata, metadata) #1 |
| |
| ; Function Attrs: argmemonly nounwind |
| declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i1) #2 |
| |
| attributes #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" } |
| attributes #1 = { nounwind readnone speculatable } |
| attributes #2 = { argmemonly nounwind } |
| |
| !llvm.dbg.cu = !{!2} |
| !llvm.module.flags = !{!10, !11, !12} |
| !llvm.ident = !{!13} |
| |
| !0 = !DIGlobalVariableExpression(var: !1, expr: !DIExpression()) |
| !1 = distinct !DIGlobalVariable(name: "g", scope: !2, file: !3, line: 3, type: !6, isLocal: false, isDefinition: true) |
| !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) |
| !3 = !DIFile(filename: "foo.c", directory: "/bar") |
| !4 = !{} |
| !5 = !{!0} |
| !6 = !DICompositeType(tag: DW_TAG_array_type, baseType: !7, size: 8, elements: !8) |
| !7 = !DIBasicType(name: "char", size: 8, encoding: DW_ATE_signed_char) |
| !8 = !{!9} |
| !9 = !DISubrange(count: 1) |
| !10 = !{i32 2, !"Dwarf Version", i32 4} |
| !11 = !{i32 2, !"Debug Info Version", i32 3} |
| !12 = !{i32 1, !"wchar_size", i32 4} |
| !13 = !{!"clang version 6.0.0"} |
| !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) |
| !15 = !DISubroutineType(types: !16) |
| !16 = !{null} |
| !17 = !DILocalVariable(name: "i", scope: !14, file: !3, line: 7, type: !7) |
| !18 = !DILocation(line: 7, column: 10, scope: !14) |
| !19 = !DILocation(line: 8, column: 7, scope: !14) |
| !20 = !DILocation(line: 9, column: 5, scope: !14) |
| !21 = !DILocation(line: 10, column: 1, scope: !14) |
| |
| ; Check that the both the store and memcpy are removed because they both access |
| ; an alloca that is not read. |
| ; CHECK-LABEL: foo |
| ; CHECK-NOT: store i8 |
| ; CHECK-NOT: call void @llvm.memcpy |
| ; CHECK: ret void |