forked from OSchip/llvm-project
91 lines
2.1 KiB
LLVM
91 lines
2.1 KiB
LLVM
; RUN: opt < %s -basicaa -gvn -dse -S | FileCheck %s
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declare void @llvm.memset.i32(i8*, i8, i32, i32)
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declare void @llvm.memset.i8(i8*, i8, i8, i32)
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declare void @llvm.memcpy.i8(i8*, i8*, i8, i32)
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declare void @llvm.lifetime.end(i64, i8* nocapture)
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declare void @external(i32*)
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define i32 @test0(i8* %P) {
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%A = alloca i32
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call void @external(i32* %A)
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store i32 0, i32* %A
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call void @llvm.memset.i32(i8* %P, i8 0, i32 42, i32 1)
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%B = load i32* %A
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ret i32 %B
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; CHECK: @test0
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; CHECK: ret i32 0
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}
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declare void @llvm.memcpy.i8(i8*, i8*, i8, i32)
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define i8 @test1() {
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; CHECK: @test1
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%A = alloca i8
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%B = alloca i8
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store i8 2, i8* %B ;; Not written to by memcpy
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call void @llvm.memcpy.i8(i8* %A, i8* %B, i8 -1, i32 0)
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%C = load i8* %B
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ret i8 %C
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; CHECK: ret i8 2
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}
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define i8 @test2(i8* %P) {
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; CHECK: @test2
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%P2 = getelementptr i8* %P, i32 127
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store i8 1, i8* %P2 ;; Not dead across memset
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call void @llvm.memset.i8(i8* %P, i8 2, i8 127, i32 0)
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%A = load i8* %P2
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ret i8 %A
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; CHECK: ret i8 1
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}
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define i8 @test2a(i8* %P) {
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; CHECK: @test2
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%P2 = getelementptr i8* %P, i32 126
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;; FIXME: DSE isn't zapping this dead store.
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store i8 1, i8* %P2 ;; Dead, clobbered by memset.
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call void @llvm.memset.i8(i8* %P, i8 2, i8 127, i32 0)
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%A = load i8* %P2
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ret i8 %A
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; CHECK: %A = load i8* %P2
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; CHECK: ret i8 %A
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}
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define void @test3(i8* %P, i8 %X) {
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; CHECK: @test3
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; CHECK-NOT: store
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; CHECK-NOT: %Y
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%Y = add i8 %X, 1 ;; Dead, because the only use (the store) is dead.
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%P2 = getelementptr i8* %P, i32 2
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store i8 %Y, i8* %P2 ;; Not read by lifetime.end, should be removed.
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; CHECK: store i8 2, i8* %P2
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call void @llvm.lifetime.end(i64 1, i8* %P)
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store i8 2, i8* %P2
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; CHECK-NOT: store
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ret void
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; CHECK: ret void
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}
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define void @test3a(i8* %P, i8 %X) {
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; CHECK: @test3a
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%Y = add i8 %X, 1 ;; Dead, because the only use (the store) is dead.
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%P2 = getelementptr i8* %P, i32 2
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store i8 %Y, i8* %P2 ;; FIXME: Killed by llvm.lifetime.end, should be zapped.
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; CHECK: store i8 %Y, i8* %P2
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call void @llvm.lifetime.end(i64 10, i8* %P)
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ret void
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; CHECK: ret void
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} |