From eff3f6451cd54055a4d2b6cff29b73ca8e427f8c Mon Sep 17 00:00:00 2001
From: Benjamin Maxwell <benjamin.maxwell@arm.com>
Date: Tue, 23 Jul 2024 13:51:54 +0000
Subject: [PATCH] Review fixups

---
 .../Transforms/VectorMaskElimination.cpp      | 24 ++++++++++---------
 1 file changed, 13 insertions(+), 11 deletions(-)

diff --git a/mlir/lib/Dialect/Vector/Transforms/VectorMaskElimination.cpp b/mlir/lib/Dialect/Vector/Transforms/VectorMaskElimination.cpp
index 486784a9cf102b3..9ad0de5cadeaee9 100644
--- a/mlir/lib/Dialect/Vector/Transforms/VectorMaskElimination.cpp
+++ b/mlir/lib/Dialect/Vector/Transforms/VectorMaskElimination.cpp
@@ -68,26 +68,28 @@ LogicalResult resolveAllTrueCreateMaskOp(IRRewriter &rewriter,
   for (auto [i, dimSize] : unknownDims) {
     // Compute the lower bound for the unknown dimension (i.e. the smallest
     // value it could be).
-    auto lowerBound =
+    FailureOr<ConstantOrScalableBound> dimLowerBound =
         vector::ScalableValueBoundsConstraintSet::computeScalableBound(
             dimSize, {}, vscaleRange.vscaleMin, vscaleRange.vscaleMax,
             presburger::BoundType::LB);
-    if (failed(lowerBound))
+    if (failed(dimLowerBound))
       return failure();
-    auto boundSize = lowerBound->getSize();
-    if (failed(boundSize))
+    auto dimLowerBoundSize = dimLowerBound->getSize();
+    if (failed(dimLowerBoundSize))
       return failure();
-    if (boundSize->scalable) {
-      // If the lower bound is scalable and >= to the mask dim size then this
-      // dim is all-true.
-      if (boundSize->baseSize < maskTypeDimSizes[i])
+    if (dimLowerBoundSize->scalable) {
+      // If the lower bound is scalable and < the mask dim size then this dim is
+      // not all-true.
+      if (dimLowerBoundSize->baseSize < maskTypeDimSizes[i])
         return failure();
     } else {
-      // If the lower bound is a constant and >= to the _fixed-size_ mask dim
-      // size then this dim is all-true.
+      // If the lower bound is a constant:
+      // - If the mask dim size is scalable then this dim is not all-true.
       if (maskTypeDimScalableFlags[i])
         return failure();
-      if (boundSize->baseSize < maskTypeDimSizes[i])
+      // - If the lower bound is < the _fixed-size_ mask dim size then this dim
+      // is not all-true.
+      if (dimLowerBoundSize->baseSize < maskTypeDimSizes[i])
         return failure();
     }
   }