llvm-mirror/test/Transforms/DeadStoreElimination/memintrinsics.ll
Nick Lewycky f6be02e523 Reapply r86359, "Teach dead store elimination that certain intrinsics write to
memory just like a store" with bug fixed (partial-overwrite.ll is the
regression test).

llvm-svn: 86667
2009-11-10 06:46:40 +00:00

48 lines
877 B
LLVM

; RUN: opt -S -dse < %s | FileCheck %s
declare void @llvm.memcpy.i8(i8*, i8*, i8, i32)
declare void @llvm.memmove.i8(i8*, i8*, i8, i32)
declare void @llvm.memset.i8(i8*, i8, i8, i32)
define void @test1() {
; CHECK: @test1
%A = alloca i8
%B = alloca i8
store i8 0, i8* %A ;; Written to by memcpy
; CHECK-NOT: store
call void @llvm.memcpy.i8(i8* %A, i8* %B, i8 -1, i32 0)
ret void
; CHECK: ret void
}
define void @test2() {
; CHECK: @test2
%A = alloca i8
%B = alloca i8
store i8 0, i8* %A ;; Written to by memmove
; CHECK-NOT: store
call void @llvm.memmove.i8(i8* %A, i8* %B, i8 -1, i32 0)
ret void
; CHECK: ret void
}
define void @test3() {
; CHECK: @test3
%A = alloca i8
%B = alloca i8
store i8 0, i8* %A ;; Written to by memset
; CHECK-NOT: store
call void @llvm.memset.i8(i8* %A, i8 0, i8 -1, i32 0)
ret void
; CHECK: ret void
}