refine

Author: lipracer

mlir/lib/Analysis/FlatLinearValueConstraints.cpp

@@ -67,7 +67,9 @@ struct AffineExprFlattener : public SimpleAffineExprFlattener {
 } // namespace
 
 // Flattens the expressions in map. Returns failure if 'expr' was unable to be
-// flattened (i.e., semi-affine expressions not handled yet).
+// flattened.For example two specific cases:
+// 1. semi-affine expressions not handled yet.
+// 2. has poison expression (i.e., division by zero).
 static LogicalResult
 getFlattenedAffineExprs(ArrayRef<AffineExpr> exprs, unsigned numDims,
                         unsigned numSymbols,

mlir/lib/Dialect/Affine/IR/AffineOps.cpp

@@ -786,12 +786,14 @@ getBoundForExpr(AffineExpr expr, unsigned numDims, unsigned numSymbols,
   // symbolic input depending on `isUpper` to determine the bound.
   for (unsigned i = 0, e = numDims + numSymbols; i < e; ++i) {
     if (flattenedExpr[i] > 0) {
-      auto &constBound = isUpper ? constUpperBounds[i] : constLowerBounds[i];
+      const std::optional<int64_t> &constBound =
+          isUpper ? constUpperBounds[i] : constLowerBounds[i];
       if (!constBound)
         return std::nullopt;
       bound += *constBound * flattenedExpr[i];
     } else if (flattenedExpr[i] < 0) {
-      auto &constBound = isUpper ? constLowerBounds[i] : constUpperBounds[i];
+      const std::optional<int64_t> &constBound =
+          isUpper ? constLowerBounds[i] : constUpperBounds[i];
       if (!constBound)
         return std::nullopt;
       bound += *constBound * flattenedExpr[i];

mlir/lib/Dialect/Affine/IR/CMakeLists.txt

@@ -16,9 +16,9 @@ add_mlir_dialect_library(MLIRAffineDialect
   MLIRDialectUtils
   MLIRIR
   MLIRLoopLikeInterface
+  MLIRMemRefDialect
   MLIRShapedOpInterfaces
   MLIRSideEffectInterfaces
   MLIRValueBoundsOpInterface
-  MLIRMemRefDialect
   MLIRUBDialect
   )