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