[Mlir-commits] [mlir] [MLIR] Introduce new C bindings to differentiate between discardable and inherent attributes (PR #66332)

[Mehdi Amini]

================
@@ -552,25 +552,69 @@ MLIR_CAPI_EXPORTED intptr_t mlirOperationGetNumSuccessors(MlirOperation op);
 MLIR_CAPI_EXPORTED MlirBlock mlirOperationGetSuccessor(MlirOperation op,
                                                        intptr_t pos);
 
+/// Returns an inherent attribute attached to the operation given its name.
+MLIR_CAPI_EXPORTED MlirAttribute
+mlirOperationGetInherentAttributeByName(MlirOperation op, MlirStringRef name);
+
+/// Sets an inherent attribute by name, replacing the existing if it exists.
+/// This has no effect if "name" does not match an inherent attribute.
+MLIR_CAPI_EXPORTED void
+mlirOperationSetInherentAttributeByName(MlirOperation op, MlirStringRef name,
+                                        MlirAttribute attr);
+
+/// Returns the number of discardable attributes attached to the operation.
+MLIR_CAPI_EXPORTED intptr_t
+mlirOperationGetNumDiscardableAttributes(MlirOperation op);
+
+/// Return `pos`-th discardable attribute of the operation.
+MLIR_CAPI_EXPORTED MlirNamedAttribute
+mlirOperationGetDiscardableAttribute(MlirOperation op, intptr_t pos);
+
+/// Returns a discardable attribute attached to the operation given its name.
+MLIR_CAPI_EXPORTED MlirAttribute mlirOperationGetDiscardableAttributeByName(
+    MlirOperation op, MlirStringRef name);
+
+/// Sets a discardable attribute by name, replacing the existing if it exists or
+/// adding a new one otherwise.
----------------
joker-eph wrote:

We don't even document it in the C++ API!
I had to read the implementation to find:


```
Attribute NamedAttrList::set(StringAttr name, Attribute value) {
  assert(value && "attributes may never be null");
```

https://github.com/llvm/llvm-project/pull/66332