1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
; RUN: opt < %s -S -basicaa -memcpyopt | FileCheck %s
target datalayout = "E-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64"
declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i1) nounwind
declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i1) nounwind
; The resulting memset is only 4-byte aligned, despite containing
; a 16-byte aligned store in the middle.
define void @foo(i32* %p) {
; CHECK-LABEL: @foo(
; CHECK: call void @llvm.memset.p0i8.i64(i8* align 4 {{.*}}, i8 0, i64 16, i1 false)
%a0 = getelementptr i32, i32* %p, i64 0
store i32 0, i32* %a0, align 4
%a1 = getelementptr i32, i32* %p, i64 1
store i32 0, i32* %a1, align 16
%a2 = getelementptr i32, i32* %p, i64 2
store i32 0, i32* %a2, align 4
%a3 = getelementptr i32, i32* %p, i64 3
store i32 0, i32* %a3, align 4
ret void
}
; Replacing %a8 with %a4 in the memset requires boosting the alignment of %a4.
define void @bar() {
; CHECK-LABEL: @bar(
; CHECK: %a4 = alloca i32, align 8
; CHECK-NOT: memcpy
%a4 = alloca i32, align 4
%a8 = alloca i32, align 8
%a8.cast = bitcast i32* %a8 to i8*
%a4.cast = bitcast i32* %a4 to i8*
call void @llvm.memset.p0i8.i64(i8* align 8 %a8.cast, i8 0, i64 4, i1 false)
call void @llvm.memcpy.p0i8.p0i8.i64(i8* align 4 %a4.cast, i8* align 4 %a8.cast, i64 4, i1 false)
ret void
}
|
