[Mlir-commits] [mlir] Add 'exact' flag to arith.shrui/shrsi/divsi/divui operations (PR #165923)

[Jakub Kuderski]

================
@@ -82,23 +79,37 @@ template <typename SourceOp, typename TargetOp>
 class AttrConvertOverflowToLLVM {
 public:
   AttrConvertOverflowToLLVM(SourceOp srcOp) {
+    using IntegerOverflowFlagsAttr = LLVM::IntegerOverflowFlagsAttr;
+
     // Copy the source attributes.
     convertedAttr = NamedAttrList{srcOp->getAttrs()};
     // Get the name of the arith overflow attribute.
     StringRef arithAttrName = SourceOp::getIntegerOverflowAttrName();
-    // Remove the source overflow attribute.
+    // Remove the source overflow attribute from the set that will be present
+    // in the target.
     if (auto arithAttr = dyn_cast_if_present<arith::IntegerOverflowFlagsAttr>(
             convertedAttr.erase(arithAttrName))) {
-      overflowFlags = convertArithOverflowFlagsToLLVM(arithAttr.getValue());
+      auto llvmFlag = convertArithOverflowFlagsToLLVM(arithAttr.getValue());
+      // Create a dictionary attribute holding the overflow flags property.
+      // (In the LLVM dialect, the overflow flags are a property, not an
+      // attribute.)
+      MLIRContext *ctx = srcOp.getOperation()->getContext();
+      Builder b(ctx);
+      auto llvmFlagAttr = IntegerOverflowFlagsAttr::get(ctx, llvmFlag);
+      StringRef llvmAttrName = TargetOp::getOverflowFlagsAttrName();
+      SmallVector<NamedAttribute> attrs;
+      attrs.push_back(b.getNamedAttr(llvmAttrName, llvmFlagAttr));
+      // Set the properties attribute of the operation state so that the
+      // property can be updated when the operation is created.
+      propertiesAttr = b.getDictionaryAttr(attrs);
----------------
kuhar wrote:

You don't need a vector just to create a single-element array ref:

```suggestion
      // Set the properties attribute of the operation state so that the
      // property can be updated when the operation is created.
      NamedAttribute attr{llvmAttrName, llvmFlagAttr};
      propertiesAttr = b.getDictionaryAttr(ArrayRef(attr));
```

https://github.com/llvm/llvm-project/pull/165923