| ; 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 |
| } |