; RUN: opt -S -dse < %s | FileCheck %s
target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
; This test is not relevant for DSE with MemorySSA. Non-memory instructions
; are ignored anyways. The limits for the MemorySSA traversal are tested in
; llvm/test/Transforms/DeadStoreElimination/MSSA/memoryssa-scan-limit.ll
@x = global i32 0, align 4
; Function Attrs: nounwind
define i32 @test_within_limit() !dbg !4 {
entry:
; The first store; later there is a second store to the same location,
; so this store should be optimized away by DSE.
; CHECK-NOT: store i32 1, i32* @x, align 4
store i32 1, i32* @x, align 4
; Insert 98 dummy instructions between the two stores
%0 = bitcast i32 0 to i32
%1 = bitcast i32 0 to i32
%2 = bitcast i32 0 to i32
%3 = bitcast i32 0 to i32
%4 = bitcast i32 0 to i32
%5 = bitcast i32 0 to i32
%6 = bitcast i32 0 to i32
%7 = bitcast i32 0 to i32
%8 = bitcast i32 0 to i32
%9 = bitcast i32 0 to i32
%10 = bitcast i32 0 to i32
%11 = bitcast i32 0 to i32
%12 = bitcast i32 0 to i32
%13 = bitcast i32 0 to i32
%14 = bitcast i32 0 to i32
%15 = bitcast i32 0 to i32
%16 = bitcast i32 0 to i32
%17 = bitcast i32 0 to i32
%18 = bitcast i32 0 to i32
%19 = bitcast i32 0 to i32
%20 = bitcast i32 0 to i32
%21 = bitcast i32 0 to i32
%22 = bitcast i32 0 to i32
%23 = bitcast i32 0 to i32
%24 = bitcast i32 0 to i32
%25 = bitcast i32 0 to i32
%26 = bitcast i32 0 to i32
%27 = bitcast i32 0 to i32
%28 = bitcast i32 0 to i32
%29 = bitcast i32 0 to i32
%30 = bitcast i32 0 to i32
%31 = bitcast i32 0 to i32
%32 = bitcast i32 0 to i32
%33 = bitcast i32 0 to i32
%34 = bitcast i32 0 to i32
%35 = bitcast i32 0 to i32
%36 = bitcast i32 0 to i32
%37 = bitcast i32 0 to i32
%38 = bitcast i32 0 to i32
%39 = bitcast i32 0 to i32
%40 = bitcast i32 0 to i32
%41 = bitcast i32 0 to i32
%42 = bitcast i32 0 to i32
%43 = bitcast i32 0 to i32
%44 = bitcast i32 0 to i32
%45 = bitcast i32 0 to i32
%46 = bitcast i32 0 to i32
%47 = bitcast i32 0 to i32
%48 = bitcast i32 0 to i32
%49 = bitcast i32 0 to i32
%50 = bitcast i32 0 to i32
%51 = bitcast i32 0 to i32
%52 = bitcast i32 0 to i32
%53 = bitcast i32 0 to i32
%54 = bitcast i32 0 to i32
%55 = bitcast i32 0 to i32
%56 = bitcast i32 0 to i32
%57 = bitcast i32 0 to i32
%58 = bitcast i32 0 to i32
%59 = bitcast i32 0 to i32
%60 = bitcast i32 0 to i32
%61 = bitcast i32 0 to i32
%62 = bitcast i32 0 to i32
%63 = bitcast i32 0 to i32
%64 = bitcast i32 0 to i32
%65 = bitcast i32 0 to i32
%66 = bitcast i32 0 to i32
%67 = bitcast i32 0 to i32
%68 = bitcast i32 0 to i32
%69 = bitcast i32 0 to i32
%70 = bitcast i32 0 to i32
%71 = bitcast i32 0 to i32
%72 = bitcast i32 0 to i32
%73 = bitcast i32 0 to i32
%74 = bitcast i32 0 to i32
%75 = bitcast i32 0 to i32
%76 = bitcast i32 0 to i32
%77 = bitcast i32 0 to i32
%78 = bitcast i32 0 to i32
%79 = bitcast i32 0 to i32
%80 = bitcast i32 0 to i32
%81 = bitcast i32 0 to i32
%82 = bitcast i32 0 to i32
%83 = bitcast i32 0 to i32
%84 = bitcast i32 0 to i32
%85 = bitcast i32 0 to i32
%86 = bitcast i32 0 to i32
%87 = bitcast i32 0 to i32
%88 = bitcast i32 0 to i32
%89 = bitcast i32 0 to i32
%90 = bitcast i32 0 to i32
%91 = bitcast i32 0 to i32
%92 = bitcast i32 0 to i32
%93 = bitcast i32 0 to i32
%94 = bitcast i32 0 to i32
%95 = bitcast i32 0 to i32
%96 = bitcast i32 0 to i32
%97 = bitcast i32 0 to i32
; Insert a meaningless dbg.value intrinsic; it should have no
; effect on the working of DSE in any way.
call void @llvm.dbg.value(metadata i32 undef, metadata !10, metadata !DIExpression()), !dbg !DILocation(scope: !4)
; CHECK: store i32 -1, i32* @x, align 4
store i32 -1, i32* @x, align 4
ret i32 0
}
; Function Attrs: nounwind
define i32 @test_outside_limit() {
entry:
; The first store; later there is a second store to the same location
; CHECK-NOT: store i32 1, i32* @x, align 4
store i32 1, i32* @x, align 4
; Insert 99 dummy instructions between the two stores; this is
; one too many instruction for the DSE to take place.
%0 = bitcast i32 0 to i32
%1 = bitcast i32 0 to i32
%2 = bitcast i32 0 to i32
%3 = bitcast i32 0 to i32
%4 = bitcast i32 0 to i32
%5 = bitcast i32 0 to i32
%6 = bitcast i32 0 to i32
%7 = bitcast i32 0 to i32
%8 = bitcast i32 0 to i32
%9 = bitcast i32 0 to i32
%10 = bitcast i32 0 to i32
%11 = bitcast i32 0 to i32
%12 = bitcast i32 0 to i32
%13 = bitcast i32 0 to i32
%14 = bitcast i32 0 to i32
%15 = bitcast i32 0 to i32
%16 = bitcast i32 0 to i32
%17 = bitcast i32 0 to i32
%18 = bitcast i32 0 to i32
%19 = bitcast i32 0 to i32
%20 = bitcast i32 0 to i32
%21 = bitcast i32 0 to i32
%22 = bitcast i32 0 to i32
%23 = bitcast i32 0 to i32
%24 = bitcast i32 0 to i32
%25 = bitcast i32 0 to i32
%26 = bitcast i32 0 to i32
%27 = bitcast i32 0 to i32
%28 = bitcast i32 0 to i32
%29 = bitcast i32 0 to i32
%30 = bitcast i32 0 to i32
%31 = bitcast i32 0 to i32
%32 = bitcast i32 0 to i32
%33 = bitcast i32 0 to i32
%34 = bitcast i32 0 to i32
%35 = bitcast i32 0 to i32
%36 = bitcast i32 0 to i32
%37 = bitcast i32 0 to i32
%38 = bitcast i32 0 to i32
%39 = bitcast i32 0 to i32
%40 = bitcast i32 0 to i32
%41 = bitcast i32 0 to i32
%42 = bitcast i32 0 to i32
%43 = bitcast i32 0 to i32
%44 = bitcast i32 0 to i32
%45 = bitcast i32 0 to i32
%46 = bitcast i32 0 to i32
%47 = bitcast i32 0 to i32
%48 = bitcast i32 0 to i32
%49 = bitcast i32 0 to i32
%50 = bitcast i32 0 to i32
%51 = bitcast i32 0 to i32
%52 = bitcast i32 0 to i32
%53 = bitcast i32 0 to i32
%54 = bitcast i32 0 to i32
%55 = bitcast i32 0 to i32
%56 = bitcast i32 0 to i32
%57 = bitcast i32 0 to i32
%58 = bitcast i32 0 to i32
%59 = bitcast i32 0 to i32
%60 = bitcast i32 0 to i32
%61 = bitcast i32 0 to i32
%62 = bitcast i32 0 to i32
%63 = bitcast i32 0 to i32
%64 = bitcast i32 0 to i32
%65 = bitcast i32 0 to i32
%66 = bitcast i32 0 to i32
%67 = bitcast i32 0 to i32
%68 = bitcast i32 0 to i32
%69 = bitcast i32 0 to i32
%70 = bitcast i32 0 to i32
%71 = bitcast i32 0 to i32
%72 = bitcast i32 0 to i32
%73 = bitcast i32 0 to i32
%74 = bitcast i32 0 to i32
%75 = bitcast i32 0 to i32
%76 = bitcast i32 0 to i32
%77 = bitcast i32 0 to i32
%78 = bitcast i32 0 to i32
%79 = bitcast i32 0 to i32
%80 = bitcast i32 0 to i32
%81 = bitcast i32 0 to i32
%82 = bitcast i32 0 to i32
%83 = bitcast i32 0 to i32
%84 = bitcast i32 0 to i32
%85 = bitcast i32 0 to i32
%86 = bitcast i32 0 to i32
%87 = bitcast i32 0 to i32
%88 = bitcast i32 0 to i32
%89 = bitcast i32 0 to i32
%90 = bitcast i32 0 to i32
%91 = bitcast i32 0 to i32
%92 = bitcast i32 0 to i32
%93 = bitcast i32 0 to i32
%94 = bitcast i32 0 to i32
%95 = bitcast i32 0 to i32
%96 = bitcast i32 0 to i32
%97 = bitcast i32 0 to i32
%98 = bitcast i32 0 to i32
; CHECK: store i32 -1, i32* @x, align 4
store i32 -1, i32* @x, align 4
ret i32 0
}
; Function Attrs: nounwind readnone
declare void @llvm.dbg.value(metadata, metadata, metadata)
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!11, !13}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, producer: "clang version 3.4", isOptimized: true, emissionKind: FullDebug, file: !1, enums: !2, retainedTypes: !2, globals: !2, imports: !2)
!1 = !DIFile(filename: "test.c", directory: "/home/tmp")
!2 = !{}
!4 = distinct !DISubprogram(name: "test_within_limit", line: 3, isLocal: false, isDefinition: true, virtualIndex: 6, flags: DIFlagPrototyped, isOptimized: false, unit: !0, scopeLine: 4, file: !1, scope: !5, type: !6, retainedNodes: !2)
!5 = !DIFile(filename: "test.c", directory: "/home/tmp")
!6 = !DISubroutineType(types: !7)
!7 = !{!8}
!8 = !DIBasicType(tag: DW_TAG_base_type, name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!9 = !{!10}
!10 = !DILocalVariable(name: "x", scope: !4, type: !8)
!11 = !{i32 2, !"Dwarf Version", i32 4}
!12 = !{i32* undef}
!13 = !{i32 1, !"Debug Info Version", i32 3}