[clang] [mlir][arith] Fix canon pattern for large ints in chained arith (PR #68900)

[Rik Huijzer via cfe-commits]

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@@ -39,26 +39,29 @@ using namespace mlir::arith;
 static IntegerAttr
 applyToIntegerAttrs(PatternRewriter &builder, Value res, Attribute lhs,
                     Attribute rhs,
-                    function_ref<int64_t(int64_t, int64_t)> binFn) {
-  return builder.getIntegerAttr(res.getType(),
-                                binFn(llvm::cast<IntegerAttr>(lhs).getInt(),
-                                      llvm::cast<IntegerAttr>(rhs).getInt()));
+                    function_ref<APInt(const APInt &, const APInt &)> binFn) {
+  APInt lhsVal = llvm::cast<IntegerAttr>(lhs).getValue();
+  APInt rhsVal = llvm::cast<IntegerAttr>(rhs).getValue();
+  APInt value = binFn(lhsVal, rhsVal);
+  return IntegerAttr::get(res.getType(), value);
 }
 
 static IntegerAttr addIntegerAttrs(PatternRewriter &builder, Value res,
                                    Attribute lhs, Attribute rhs) {
-  return applyToIntegerAttrs(builder, res, lhs, rhs, std::plus<int64_t>());
+  auto binFn = [](const APInt &a, const APInt &b) -> APInt { return a + b; };
+  return applyToIntegerAttrs(builder, res, lhs, rhs, binFn);
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rikhuijzer wrote:

Well spotted 👍 

https://github.com/llvm/llvm-project/pull/68900