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
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
|
; RUN: opt -S < %s -instcombine | FileCheck %s
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-apple-macosx10.7.0"
; Check transforms involving atomic operations
define i32 @test1(i32* %p) {
; CHECK-LABEL: define i32 @test1(
; CHECK: %x = load atomic i32, i32* %p seq_cst, align 4
; CHECK: shl i32 %x, 1
%x = load atomic i32, i32* %p seq_cst, align 4
%y = load i32, i32* %p, align 4
%z = add i32 %x, %y
ret i32 %z
}
define i32 @test2(i32* %p) {
; CHECK-LABEL: define i32 @test2(
; CHECK: %x = load volatile i32, i32* %p, align 4
; CHECK: %y = load volatile i32, i32* %p, align 4
%x = load volatile i32, i32* %p, align 4
%y = load volatile i32, i32* %p, align 4
%z = add i32 %x, %y
ret i32 %z
}
; The exact semantics of mixing volatile and non-volatile on the same
; memory location are a bit unclear, but conservatively, we know we don't
; want to remove the volatile.
define i32 @test3(i32* %p) {
; CHECK-LABEL: define i32 @test3(
; CHECK: %x = load volatile i32, i32* %p, align 4
%x = load volatile i32, i32* %p, align 4
%y = load i32, i32* %p, align 4
%z = add i32 %x, %y
ret i32 %z
}
; FIXME: Forwarding from a stronger atomic is fine
define i32 @test4(i32* %p) {
; CHECK-LABEL: define i32 @test4(
; CHECK: %x = load atomic i32, i32* %p seq_cst, align 4
; CHECK: %y = load atomic i32, i32* %p unordered, align 4
%x = load atomic i32, i32* %p seq_cst, align 4
%y = load atomic i32, i32* %p unordered, align 4
%z = add i32 %x, %y
ret i32 %z
}
; Forwarding from a non-atomic is not. (The earlier load
; could in priciple be promoted to atomic and then forwarded,
; but we can't just drop the atomic from the load.)
define i32 @test5(i32* %p) {
; CHECK-LABEL: define i32 @test5(
; CHECK: %x = load atomic i32, i32* %p unordered, align 4
%x = load atomic i32, i32* %p unordered, align 4
%y = load i32, i32* %p, align 4
%z = add i32 %x, %y
ret i32 %z
}
|
