; 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 | |
} |