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
|
; RUN: opt -O3 -S -analyze -scalar-evolution < %s | FileCheck %s
;
; This file contains phase ordering tests for scalar evolution.
; Test that the standard passes don't obfuscate the IR so scalar evolution can't
; recognize expressions.
; CHECK: test1
; The loop body contains two increments by %div.
; Make sure that 2*%div is recognizable, and not expressed as a bit mask of %d.
; CHECK: --> {%p,+,(8 * (%d /u 4))}
define void @test1(i64 %d, i32* %p) nounwind uwtable ssp {
entry:
%div = udiv i64 %d, 4
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%p.addr.0 = phi i32* [ %p, %entry ], [ %add.ptr1, %for.inc ]
%i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
%cmp = icmp ne i32 %i.0, 64
br i1 %cmp, label %for.body, label %for.end
for.body: ; preds = %for.cond
store i32 0, i32* %p.addr.0, align 4
%add.ptr = getelementptr inbounds i32, i32* %p.addr.0, i64 %div
store i32 1, i32* %add.ptr, align 4
%add.ptr1 = getelementptr inbounds i32, i32* %add.ptr, i64 %div
br label %for.inc
for.inc: ; preds = %for.body
%inc = add i32 %i.0, 1
br label %for.cond
for.end: ; preds = %for.cond
ret void
}
; CHECK: test1a
; Same thing as test1, but it is even more tempting to fold 2 * (%d /u 2)
; CHECK: --> {%p,+,(8 * (%d /u 2))}
define void @test1a(i64 %d, i32* %p) nounwind uwtable ssp {
entry:
%div = udiv i64 %d, 2
br label %for.cond
for.cond: ; preds = %for.inc, %entry
%p.addr.0 = phi i32* [ %p, %entry ], [ %add.ptr1, %for.inc ]
%i.0 = phi i32 [ 0, %entry ], [ %inc, %for.inc ]
%cmp = icmp ne i32 %i.0, 64
br i1 %cmp, label %for.body, label %for.end
for.body: ; preds = %for.cond
store i32 0, i32* %p.addr.0, align 4
%add.ptr = getelementptr inbounds i32, i32* %p.addr.0, i64 %div
store i32 1, i32* %add.ptr, align 4
%add.ptr1 = getelementptr inbounds i32, i32* %add.ptr, i64 %div
br label %for.inc
for.inc: ; preds = %for.body
%inc = add i32 %i.0, 1
br label %for.cond
for.end: ; preds = %for.cond
ret void
}
|
