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
|
; The unify-function-exit-nodes pass often makes basic blocks that just contain
; a PHI node and a return. Make sure the simplify cfg can straighten out this
; important case. This is basically the most trivial form of tail-duplication.
; RUN: opt < %s -simplifycfg -S | \
; RUN: not grep "br label"
define i32 @test(i1 %B, i32 %A, i32 %B.upgrd.1) {
br i1 %B, label %T, label %F
T: ; preds = %0
br label %ret
F: ; preds = %0
br label %ret
ret: ; preds = %F, %T
%X = phi i32 [ %A, %F ], [ %B.upgrd.1, %T ] ; <i32> [#uses=1]
ret i32 %X
}
; Make sure it's willing to move unconditional branches to return instructions
; as well, even if the return block is shared and the source blocks are
; non-empty.
define i32 @test2(i1 %B, i32 %A, i32 %B.upgrd.2) {
br i1 %B, label %T, label %F
T: ; preds = %0
call i32 @test( i1 true, i32 5, i32 8 ) ; <i32>:1 [#uses=0]
br label %ret
F: ; preds = %0
call i32 @test( i1 true, i32 5, i32 8 ) ; <i32>:2 [#uses=0]
br label %ret
ret: ; preds = %F, %T
ret i32 %A
}
|
