llvm/test/Transforms/SimplifyCFG/PhiBlockMerge.ll
Dan Gohman 438b583dbd Revert r85667. LoopUnroll currently can't call utility functions which
auto-update the DominatorTree because it doesn't keep the DominatorTree
current while it works.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85670 91177308-0d34-0410-b5e6-96231b3b80d8
2009-10-31 17:33:01 +00:00

23 lines
667 B
LLVM

; Test merging of blocks that only have PHI nodes in them
;
; RUN: opt < %s -simplifycfg -S | not grep N:
;
define i32 @test(i1 %a, i1 %b) {
; <label>:0
br i1 %a, label %M, label %O
O: ; preds = %0
br i1 %b, label %N, label %Q
Q: ; preds = %O
br label %N
N: ; preds = %Q, %O
; This block should be foldable into M
%Wp = phi i32 [ 0, %O ], [ 1, %Q ] ; <i32> [#uses=1]
br label %M
M: ; preds = %N, %0
%W = phi i32 [ %Wp, %N ], [ 2, %0 ] ; <i32> [#uses=1]
%R = add i32 %W, 1 ; <i32> [#uses=1]
ret i32 %R
}