| ; Test merging of blocks that only have PHI nodes in them. This tests the case |
| ; where the mergedinto block doesn't have any PHI nodes, and is in fact |
| ; dominated by the block-to-be-eliminated |
| ; |
| ; RUN: opt < %s -simplifycfg -S | not grep N: |
| ; |
| |
| declare i1 @foo() |
| |
| define i32 @test(i1 %a, i1 %b) { |
| %c = call i1 @foo() |
| br i1 %c, label %N, label %P |
| P: |
| %d = call i1 @foo() |
| br i1 %d, label %N, label %Q |
| Q: |
| br label %N |
| N: |
| %W = phi i32 [0, %0], [1, %Q], [2, %P] |
| ; This block should be foldable into M |
| br label %M |
| |
| M: |
| %R = add i32 %W, 1 |
| ret i32 %R |
| } |
| |
