From a99c46cc73a70b57972c07562072ec5aeb6d8f4c Mon Sep 17 00:00:00 2001 From: Michael Kuperstein Date: Tue, 12 Jul 2016 21:24:06 +0000 Subject: [LV] Remove wrong assumption about LCSSA The LCSSA pass itself will not generate several redundant PHI nodes in a single exit block. However, such redundant PHI nodes don't violate LCSSA form, and may be introduced by passes that preserve LCSSA, and/or preserved by the LCSSA pass itself. So, assuming a single PHI node per exit block is not safe. llvm-svn: 275217 --- .../Transforms/LoopVectorize/iv_outside_user.ll | 25 ++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'llvm/test/Transforms/LoopVectorize') diff --git a/llvm/test/Transforms/LoopVectorize/iv_outside_user.ll b/llvm/test/Transforms/LoopVectorize/iv_outside_user.ll index 4e345f3517b..d536d1023f4 100644 --- a/llvm/test/Transforms/LoopVectorize/iv_outside_user.ll +++ b/llvm/test/Transforms/LoopVectorize/iv_outside_user.ll @@ -108,3 +108,28 @@ for.body: for.end: ret i32* %inc.lag1 } + +; CHECK-LABEL: @multiphi +; CHECK-LABEL: scalar.ph: +; CHECK: %bc.resume.val = phi i32 [ %n.vec, %middle.block ], [ 0, %entry ] +; CHECK-LABEL: for.end: +; CHECK: %phi = phi i32 [ {{.*}}, %for.body ], [ %n.vec, %middle.block ] +; CHECK: %phi2 = phi i32 [ {{.*}}, %for.body ], [ %n.vec, %middle.block ] +; CHECK: store i32 %phi2, i32* %p +; CHECK: ret i32 %phi +define i32 @multiphi(i32 %k, i32* %p) { +entry: + br label %for.body + +for.body: + %inc.phi = phi i32 [ 0, %entry ], [ %inc, %for.body ] + %inc = add nsw i32 %inc.phi, 1 + %cmp = icmp eq i32 %inc, %k + br i1 %cmp, label %for.end, label %for.body + +for.end: + %phi = phi i32 [ %inc, %for.body ] + %phi2 = phi i32 [ %inc, %for.body ] + store i32 %phi2, i32* %p + ret i32 %phi +} -- cgit v1.2.3