[mlir][CAPI] Add mlirOpOperandGetValue (#75032)

Author: jackalcooper

mlir/include/mlir-c/IR.h

@@ -940,6 +940,9 @@ MLIR_CAPI_EXPORTED void mlirValueReplaceAllUsesOfWith(MlirValue of,
 /// Returns whether the op operand is null.
 MLIR_CAPI_EXPORTED bool mlirOpOperandIsNull(MlirOpOperand opOperand);
 
+/// Returns the value of an op operand.
+MLIR_CAPI_EXPORTED MlirValue mlirOpOperandGetValue(MlirOpOperand opOperand);
+
 /// Returns the owner operation of an op operand.
 MLIR_CAPI_EXPORTED MlirOperation mlirOpOperandGetOwner(MlirOpOperand opOperand);
 

mlir/lib/CAPI/IR/IR.cpp

@@ -986,6 +986,10 @@ MlirOperation mlirOpOperandGetOwner(MlirOpOperand opOperand) {
   return wrap(unwrap(opOperand)->getOwner());
 }
 
+MlirValue mlirOpOperandGetValue(MlirOpOperand opOperand) {
+  return wrap(unwrap(opOperand)->get());
+}
+
 unsigned mlirOpOperandGetOperandNumber(MlirOpOperand opOperand) {
   return unwrap(opOperand)->getOperandNumber();
 }

mlir/test/CAPI/ir.c

@@ -1970,6 +1970,15 @@ int testOperands(void) {
   fprintf(stderr, "\n");
   // CHECK: Second replacement use owner: "dummy.op2"
 
+  MlirOpOperand use5 = mlirValueGetFirstUse(constTwoValue);
+  MlirOpOperand use6 = mlirOpOperandGetNextUse(use5);
+  if (!mlirValueEqual(mlirOpOperandGetValue(use5),
+                      mlirOpOperandGetValue(use6))) {
+    fprintf(stderr,
+            "ERROR: First and second operand should share the same value\n");
+    return 5;
+  }
+
   mlirOperationDestroy(op);
   mlirOperationDestroy(op2);
   mlirOperationDestroy(constZero);