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; RUN: opt < %s -basicaa -gvn -dse -S | FileCheck %s
target datalayout = "E-p:64:64:64-a0:0:8-f32:32:32-f64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-v64:64:64-v128:128:128"
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.memcpy.i32(i8*, i8*, i32, 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-NOT: load
; CHECK: ret i8 2
}
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
; CHECK-NEXT: call void @llvm.lifetime.end
call void @llvm.lifetime.end(i64 10, i8* %P)
ret void
; CHECK-NEXT: ret void
}
@G1 = external global i32
@G2 = external global [4000 x i32]
define i32 @test4(i8* %P) {
%tmp = load i32* @G1
call void @llvm.memset.i32(i8* bitcast ([4000 x i32]* @G2 to i8*), i8 0, i32 4000, i32 1)
%tmp2 = load i32* @G1
%sub = sub i32 %tmp2, %tmp
ret i32 %sub
; CHECK: @test4
; CHECK-NOT: load
; CHECK: memset.p0i8.i32
; CHECK-NOT: load
; CHECK: ret i32 0
}
; Verify that basicaa is handling variable length memcpy, knowing it doesn't
; write to G1.
define i32 @test5(i8* %P, i32 %Len) {
%tmp = load i32* @G1
call void @llvm.memcpy.i32(i8* bitcast ([4000 x i32]* @G2 to i8*), i8* bitcast (i32* @G1 to i8*), i32 %Len, i32 1)
%tmp2 = load i32* @G1
%sub = sub i32 %tmp2, %tmp
ret i32 %sub
; CHECK: @test5
; CHECK-NOT: load
; CHECK: memcpy.p0i8.p0i8.i32
; CHECK-NOT: load
; CHECK: ret i32 0
}
define i8 @test6(i8* %p, i8* noalias %a) {
%x = load i8* %a
%t = va_arg i8* %p, float
%y = load i8* %a
%z = add i8 %x, %y
ret i8 %z
; CHECK: @test6
; CHECK: load i8* %a
; CHECK-NOT: load
; CHECK: ret
}
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