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
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
| ;; RUN: opt -S < %s -indvars | FileCheck %s
; RUN: opt -lcssa -loop-simplify -S < %s | opt -S -passes='require<targetir>,require<scalar-evolution>,require<domtree>,loop(indvars)'
;; Check if llvm can narrow !range metadata based on loop entry
;; predicates.
declare void @abort()
define i1 @bounded_below_slt(i32* nocapture readonly %buffer) {
; CHECK-LABEL: bounded_below_slt
entry:
%length = load i32, i32* %buffer, !range !0
%entry.pred = icmp eq i32 %length, 0
br i1 %entry.pred, label %abort, label %loop.preheader
loop.preheader:
br label %loop
loop:
; CHECK: loop
%idx = phi i32 [ %idx.inc, %loop.next ], [ 0, %loop.preheader ]
%oob.pred = icmp slt i32 %idx, %length
br i1 %oob.pred, label %loop.next, label %oob
; CHECK: br i1 true, label %loop.next, label %oob
loop.next:
; CHECK: loop.next
%idx.inc = add i32 %idx, 1
%exit.pred = icmp slt i32 %idx.inc, %length
br i1 %exit.pred, label %loop, label %abort.loopexit
abort.loopexit:
br label %abort
abort:
ret i1 false
oob:
tail call void @abort()
ret i1 false
}
define i1 @bounded_below_sle(i32* nocapture readonly %buffer) {
; CHECK-LABEL: bounded_below_sle
entry:
%length = load i32, i32* %buffer, !range !0
%entry.pred = icmp eq i32 %length, 0
br i1 %entry.pred, label %abort, label %loop.preheader
loop.preheader:
br label %loop
loop:
; CHECK: loop
%idx = phi i32 [ %idx.inc, %loop.next ], [ 0, %loop.preheader ]
%oob.pred = icmp sle i32 %idx, %length
br i1 %oob.pred, label %loop.next, label %oob
; CHECK: br i1 true, label %loop.next, label %oob
loop.next:
; CHECK: loop.next
%idx.inc = add i32 %idx, 1
%exit.pred = icmp sle i32 %idx.inc, %length
br i1 %exit.pred, label %loop, label %abort.loopexit
abort.loopexit:
br label %abort
abort:
ret i1 false
oob:
tail call void @abort()
ret i1 false
}
;; Assert that we're not making an incorrect transform.
declare i32 @check(i8*)
define void @NoChange() {
; CHECK-LABEL: NoChange
entry:
br label %loop.begin
loop.begin:
; CHECK: loop.begin:
%i.01 = phi i64 [ 2, %entry ], [ %add, %loop.end ]
%cmp = icmp ugt i64 %i.01, 1
; CHECK: %cmp = icmp ugt i64 %i.01, 1
br i1 %cmp, label %loop, label %loop.end
loop:
; CHECK: loop
%.sum = add i64 %i.01, -2
%v = getelementptr inbounds i8, i8* null, i64 %.sum
%r = tail call i32 @check(i8* %v)
%c = icmp eq i32 %r, 0
br i1 %c, label %loop.end, label %abort.now
abort.now:
tail call void @abort()
unreachable
loop.end:
%add = add i64 %i.01, -1
%eq = icmp eq i64 %add, 0
br i1 %eq, label %exit, label %loop.begin
exit:
ret void
}
!0 = !{i32 0, i32 100}
|