[LV] Ensure proper handling of multi-use case when collecting uniforms

The test case included in r280979 wasn't checking what it was supposed to be
checking for the predicated store case. Fixing the test revealed that the
multi-use case (when a pointer is used by both vectorized and scalarized memory
accesses) wasn't being handled properly. We can't skip over
non-consecutive-like pointers since they may have looked consecutive-like with
a different memory access.

llvm-svn: 280992

2 files changed, 9 insertions, 6 deletions

diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
index 0e0f81fcad7..fd93ce361da 100644
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -5388,9 +5388,9 @@ void LoopVectorizationLegality::collectLoopUniforms() {
   for (auto *BB : TheLoop->blocks())
     for (auto &I : *BB) {
 
-      // If the pointer operand is not consecutive-like, there's nothing to do.
+      // If there's no pointer operand, there's nothing to do.
       auto *Ptr = dyn_cast_or_null<Instruction>(getPointerOperand(&I));
-      if (!Ptr || isUniform(Ptr) || !hasConsecutiveLikePtrOperand(&I))
+      if (!Ptr)
         continue;
 
       // Ensure the memory instruction will not be scalarized, making its
@@ -5398,9 +5398,9 @@ void LoopVectorizationLegality::collectLoopUniforms() {
       if (memoryInstructionMustBeScalarized(&I))
         PossibleNonUniformPtrs.insert(Ptr);
 
-      // If the memory instruction will be vectorized, its consecutive-like
-      // pointer operand should remain uniform.
-      else
+      // If the memory instruction will be vectorized and its pointer operand
+      // is consecutive-like, the pointer operand should remain uniform.
+      else if (hasConsecutiveLikePtrOperand(&I))
         ConsecutiveLikePtrs.insert(Ptr);
     }
 
diff --git a/llvm/test/Transforms/LoopVectorize/consecutive-ptr-uniforms.ll b/llvm/test/Transforms/LoopVectorize/consecutive-ptr-uniforms.ll
index 66636f6a1b0..f1fc1aa6836 100644
--- a/llvm/test/Transforms/LoopVectorize/consecutive-ptr-uniforms.ll
+++ b/llvm/test/Transforms/LoopVectorize/consecutive-ptr-uniforms.ll
@@ -71,7 +71,9 @@ for.end:
   %tmp4 = phi i32 [ %tmp3, %for.body ]
   ret i32 %tmp4
 }
+
 ; CHECK-LABEL: interleaved_access_forward
+; INTER-LABEL: interleaved_access_forward
 ;
 ; Check that a consecutive-like pointer used by a forward interleaved group is
 ; recognized as uniform and remains uniform after vectorization. When
@@ -127,6 +129,7 @@ for.end:
 }
 
 ; CHECK-LABEL: interleaved_access_reverse
+; INTER-LABEL: interleaved_access_reverse
 ;
 ; Check that a consecutive-like pointer used by a reverse interleaved group is
 ; recognized as uniform and remains uniform after vectorization. When
@@ -185,7 +188,7 @@ for.end:
   ret i32 %tmp14
 }
 
-; CHECK-LABEL: predicated_store
+; INTER-LABEL: predicated_store
 ;
 ; Check that a consecutive-like pointer used by a forward interleaved group and
 ; scalarized store is not recognized as uniform and is not uniform after