llvm/test/Transforms/LoopStrengthReduce/dead-phi.ll
Dan Gohman cbfe5bbe88 Improve LSR's dead-phi detection to handle use-def cycles
with more than two nodes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52617 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-22 20:44:02 +00:00

22 lines
461 B
LLVM

; RUN: llvm-as < %s | opt -loop-reduce | llvm-dis | grep phi | count 1
define void @foo(i32 %n) {
entry:
br label %loop
loop:
%i = phi i32 [ 0, %entry ], [ %i.next, %loop ]
; These three instructions form an isolated cycle and can be deleted.
%j = phi i32 [ 0, %entry ], [ %j.y, %loop ]
%j.x = add i32 %j, 1
%j.y = mul i32 %j.x, 2
%i.next = add i32 %i, 1
%c = icmp ne i32 %i.next, %n
br i1 %c, label %loop, label %exit
exit:
ret void
}