2012-11-28-merge-store-alias.ll
1.65 KB
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; RUN: llc < %s -mcpu=corei7 -mtriple=x86_64-pc-win64 | FileCheck %s
; CHECK: merge_stores_can
; CHECK: callq foo
; CHECK: xorps %xmm0, %xmm0
; CHECK-NEXT: movups %xmm0
; CHECK-NEXT: movl 36(%rsp), %ebp
; CHECK: callq foo
; CHECK: ret
declare i32 @foo([10 x i32]* )
define i32 @merge_stores_can() nounwind ssp {
%object1 = alloca [10 x i32]
%ret0 = call i32 @foo([10 x i32]* %object1) nounwind
%O1_1 = getelementptr [10 x i32], [10 x i32]* %object1, i64 0, i32 1
%O1_2 = getelementptr [10 x i32], [10 x i32]* %object1, i64 0, i32 2
%O1_3 = getelementptr [10 x i32], [10 x i32]* %object1, i64 0, i32 3
%O1_4 = getelementptr [10 x i32], [10 x i32]* %object1, i64 0, i32 4
%ld_ptr = getelementptr [10 x i32], [10 x i32]* %object1, i64 0, i32 9
store i32 0, i32* %O1_1
store i32 0, i32* %O1_2
%ret = load i32, i32* %ld_ptr ; <--- does not alias.
store i32 0, i32* %O1_3
store i32 0, i32* %O1_4
%ret1 = call i32 @foo([10 x i32]* %object1) nounwind
ret i32 %ret
}
; CHECK: merge_stores_cant
; CHECK-NOT: xorps %xmm0, %xmm0
; CHECK-NOT: movups %xmm0
; CHECK: ret
define i32 @merge_stores_cant([10 x i32]* %in0, [10 x i32]* %in1) nounwind ssp {
%O1_1 = getelementptr [10 x i32], [10 x i32]* %in1, i64 0, i32 1
%O1_2 = getelementptr [10 x i32], [10 x i32]* %in1, i64 0, i32 2
%O1_3 = getelementptr [10 x i32], [10 x i32]* %in1, i64 0, i32 3
%O1_4 = getelementptr [10 x i32], [10 x i32]* %in1, i64 0, i32 4
%ld_ptr = getelementptr [10 x i32], [10 x i32]* %in0, i64 0, i32 2
store i32 0, i32* %O1_1
store i32 0, i32* %O1_2
%ret = load i32, i32* %ld_ptr ; <--- may alias
store i32 0, i32* %O1_3
store i32 0, i32* %O1_4
ret i32 %ret
}