cmpxchg8b_alloca_regalloc_handling.ll
2.7 KB
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
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
; RUN: llc < %s -mtriple=i686-- -stackrealign -O2 | FileCheck %s
; PR28755
; Check that register allocator is able to handle that
; a-lot-of-fixed-and-reserved-registers case. We do that by
; emmiting lea before 4 cmpxchg8b operands generators.
define void @foo_alloca(i64* %a, i32 %off, i32 %n) {
%dummy = alloca i32, i32 %n
%addr = getelementptr inbounds i64, i64* %a, i32 %off
%res = cmpxchg i64* %addr, i64 0, i64 1 monotonic monotonic
ret void
}
; CHECK-LABEL: foo_alloca
; CHECK: leal {{\(%e..,%e..,.*\)}}, [[REGISTER:%e.i]]
; CHECK-NEXT: xorl %eax, %eax
; CHECK-NEXT: xorl %edx, %edx
; CHECK-NEXT: xorl %ecx, %ecx
; CHECK-NEXT: movl $1, %ebx
; CHECK-NEXT: lock cmpxchg8b ([[REGISTER]])
; If we don't use index register in the address mode -
; check that we did not generate the lea.
define void @foo_alloca_direct_address(i64* %addr, i32 %n) {
%dummy = alloca i32, i32 %n
%res = cmpxchg i64* %addr, i64 0, i64 1 monotonic monotonic
ret void
}
; CHECK-LABEL: foo_alloca_direct_address
; CHECK-NOT: leal {{\(%e.*\)}}, [[REGISTER:%e.i]]
; CHECK: lock cmpxchg8b ([[REGISTER]])
; We used to have a bug when combining:
; - base pointer for stack frame (VLA + alignment)
; - cmpxchg8b frameindex + index reg
declare void @escape(i32*)
define void @foo_alloca_index(i32 %i, i64 %val) {
entry:
%Counters = alloca [19 x i64], align 32
%vla = alloca i32, i32 %i
call void @escape(i32* %vla)
br label %body
body:
%p = getelementptr inbounds [19 x i64], [19 x i64]* %Counters, i32 0, i32 %i
%t2 = cmpxchg volatile i64* %p, i64 %val, i64 %val seq_cst seq_cst
%t3 = extractvalue { i64, i1 } %t2, 0
%cmp.i = icmp eq i64 %val, %t3
br i1 %cmp.i, label %done, label %body
done:
ret void
}
; Check that we add a LEA
; CHECK-LABEL: foo_alloca_index:
; CHECK: leal {{[0-9]*\(%e..,%e..,8\), %e..}}
; CHECK: lock cmpxchg8b ({{%e..}})
; We used to have a bug when combining:
; - base pointer for stack frame (VLA + alignment)
; - cmpxchg8b global + index reg
@Counters = external global [19 x i64]
define void @foo_alloca_index_global(i32 %i, i64 %val) {
entry:
%aligner = alloca i32, align 32
call void @escape(i32* %aligner)
%vla = alloca i32, i32 %i
call void @escape(i32* %vla)
br label %body
body:
%p = getelementptr inbounds [19 x i64], [19 x i64]* @Counters, i32 0, i32 %i
%t2 = cmpxchg volatile i64* %p, i64 %val, i64 %val seq_cst seq_cst
%t3 = extractvalue { i64, i1 } %t2, 0
%cmp.i = icmp eq i64 %val, %t3
br i1 %cmp.i, label %done, label %body
done:
ret void
}
; Check that we add a LEA
; CHECK-LABEL: foo_alloca_index_global:
; CHECK: leal {{Counters\(,%e..,8\), %e..}}
; CHECK: lock cmpxchg8b ({{%e..}})