[Mlir-commits] [mlir] a1a714b - [MLIR][Interfaces] Make `getMutableSuccessorOperands` overridable on `ReturnLike` ops (#186832)

[llvmlistbot at llvm.org]

Author: Robert Konicar
Date: 2026-03-17T14:12:19+01:00
New Revision: a1a714b8b87e78bd42c47cb0b0e18dacca073a19

URL: https://github.com/llvm/llvm-project/commit/a1a714b8b87e78bd42c47cb0b0e18dacca073a19
DIFF: https://github.com/llvm/llvm-project/commit/a1a714b8b87e78bd42c47cb0b0e18dacca073a19.diff

LOG: [MLIR][Interfaces] Make `getMutableSuccessorOperands` overridable on `ReturnLike` ops (#186832)

Move the `getMutableSuccessorOperands` implementation from `ReturnLike`
trait to the `RegionBranchTerminatorOpInterface` to allow overriding of
the implementation. This allows to have the trait on operations that are
not a return of all of their operands. This can be used, for example, to
implement custom `ReturnLike` terminator that consumes non-returned
operands in combination with `func.func`.

The `RegionBranchTerminatorOpInterface` now provides a default
implementation for the `getMutableSuccessorOperands` method that returns
all of the operands.

Added: 
    

Modified: 
    mlir/include/mlir/Dialect/OpenACC/OpenACCOps.td
    mlir/include/mlir/Dialect/SCF/IR/SCFOps.td
    mlir/include/mlir/Interfaces/ControlFlowInterfaces.td
    mlir/test/lib/Dialect/Test/TestOpDefs.cpp
    mlir/test/lib/Dialect/Test/TestOps.td

Removed: 
    


################################################################################
diff  --git a/mlir/include/mlir/Dialect/OpenACC/OpenACCOps.td b/mlir/include/mlir/Dialect/OpenACC/OpenACCOps.td
index 25e3dbd29043d..c8030b14e96c1 100644
--- a/mlir/include/mlir/Dialect/OpenACC/OpenACCOps.td
+++ b/mlir/include/mlir/Dialect/OpenACC/OpenACCOps.td
@@ -2354,7 +2354,8 @@ def OpenACC_DataOp
 def OpenACC_TerminatorOp
     : OpenACC_Op<"terminator", [Pure, Terminator,
                                 DeclareOpInterfaceMethods<
-                                    RegionBranchTerminatorOpInterface>]> {
+                                    RegionBranchTerminatorOpInterface,
+                                    ["getMutableSuccessorOperands"]>]> {
   let summary = "Generic terminator for OpenACC regions";
 
   let description = [{

diff  --git a/mlir/include/mlir/Dialect/SCF/IR/SCFOps.td b/mlir/include/mlir/Dialect/SCF/IR/SCFOps.td
index a08cf3c95e6ce..6ed85c611983a 100644
--- a/mlir/include/mlir/Dialect/SCF/IR/SCFOps.td
+++ b/mlir/include/mlir/Dialect/SCF/IR/SCFOps.td
@@ -54,7 +54,7 @@ class SCF_Op<string mnemonic, list<Trait> traits = []> :
 def ConditionOp : SCF_Op<"condition", [
   HasParent<"WhileOp">,
   DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface,
-    ["getSuccessorRegions"]>,
+    ["getSuccessorRegions", "getMutableSuccessorOperands"]>,
   Pure,
   Terminator
 ]> {
@@ -904,7 +904,8 @@ def ParallelOp : SCF_Op<"parallel",
 
 def ReduceOp : SCF_Op<"reduce", [
     Terminator, HasParent<"ParallelOp">, RecursiveMemoryEffects,
-    DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface>]> {
+    DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface,
+                              ["getMutableSuccessorOperands"]>]> {
   let summary = "reduce operation for scf.parallel";
   let description = [{
     The `scf.reduce` operation is the terminator for `scf.parallel` operations. It can model

diff  --git a/mlir/include/mlir/Interfaces/ControlFlowInterfaces.td b/mlir/include/mlir/Interfaces/ControlFlowInterfaces.td
index 8975b1235a7e3..06fa724e05fab 100644
--- a/mlir/include/mlir/Interfaces/ControlFlowInterfaces.td
+++ b/mlir/include/mlir/Interfaces/ControlFlowInterfaces.td
@@ -432,7 +432,11 @@ def RegionBranchTerminatorOpInterface :
         passing them to the region successor indicated by `point`.
       }],
       "::mlir::MutableOperandRange", "getMutableSuccessorOperands",
-      (ins "::mlir::RegionSuccessor":$point)
+      (ins "::mlir::RegionSuccessor":$point),
+      [{}],
+      /*defaultImplementation=*/[{
+        return ::mlir::MutableOperandRange($_op);
+      }]
     >,
     InterfaceMethod<[{
         Returns the potential region successors that are branched to after this
@@ -632,17 +636,6 @@ def WeightedRegionBranchOpInterface
 // Op is "return-like".
 def ReturnLike : TraitList<[
     DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface>,
-    NativeOpTrait<
-        /*name=*/"ReturnLike",
-        /*traits=*/[],
-        /*extraOpDeclaration=*/"",
-        /*extraOpDefinition=*/[{
-          ::mlir::MutableOperandRange $cppClass::getMutableSuccessorOperands(
-            ::mlir::RegionSuccessor successor) {
-            return ::mlir::MutableOperandRange(*this);
-          }
-        }]
-    >
-]>;
+    NativeOpTrait</*name=*/"ReturnLike">]>;
 
 #endif // MLIR_INTERFACES_CONTROLFLOWINTERFACES

diff  --git a/mlir/test/lib/Dialect/Test/TestOpDefs.cpp b/mlir/test/lib/Dialect/Test/TestOpDefs.cpp
index bd825c858a615..ed5dc5bead78a 100644
--- a/mlir/test/lib/Dialect/Test/TestOpDefs.cpp
+++ b/mlir/test/lib/Dialect/Test/TestOpDefs.cpp
@@ -1331,6 +1331,15 @@ TestCrashingReturnOp::getMutableSuccessorOperands(RegionSuccessor successor) {
   return getArgsMutable();
 }
 
+//===----------------------------------------------------------------------===//
+// TestReturnWithIgnoredValueOp
+//===----------------------------------------------------------------------===//
+
+MutableOperandRange TestReturnWithIgnoredValueOp::getMutableSuccessorOperands(
+    RegionSuccessor /*successor*/) {
+  return getValuesMutable();
+}
+
 //===----------------------------------------------------------------------===//
 // SwitchWithNoBreakOp
 //===----------------------------------------------------------------------===//

diff  --git a/mlir/test/lib/Dialect/Test/TestOps.td b/mlir/test/lib/Dialect/Test/TestOps.td
index 02bac016eeed1..4c9e6b3fe9e45 100644
--- a/mlir/test/lib/Dialect/Test/TestOps.td
+++ b/mlir/test/lib/Dialect/Test/TestOps.td
@@ -2244,7 +2244,8 @@ def TestReturnOp : TEST_Op<"return", [Pure, ReturnLike, Terminator]> {
 // emits an error, but getMutableSuccessorOperands() calls report_fatal_error
 // to expose the fact that FuncOp::verify() runs before the region is checked.
 def TestCrashingReturnOp : TEST_Op<"crashing_return", [
-    DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface>,
+    DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface,
+       ["getMutableSuccessorOperands"]>,
     Terminator]> {
   let arguments = (ins Variadic<AnyType>:$args, UnitAttr:$valid);
   let assemblyFormat = "($args^ `:` type($args))? attr-dict";
@@ -2300,6 +2301,19 @@ def TestSignatureConversionNoConverterOp
   let regions = (region AnyRegion);
 }
 
+// A return-like operation with override on the successor operand getter
+// interface method.
+def TestReturnWithIgnoredValueOp : TEST_Op<"return_with_ignored_value", [
+    Pure,
+    ReturnLike,
+    DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface, [
+      "getMutableSuccessorOperands"
+    ]>,
+    Terminator
+]> {
+  let arguments = (ins Variadic<AnyType>:$values, AnyType:$unwanted_value);
+}
+
 //===----------------------------------------------------------------------===//
 // Test parser.
 //===----------------------------------------------------------------------===//
@@ -2707,8 +2721,9 @@ def LoopBlockOp : TEST_Op<"loop_block",
 }
 
 def LoopBlockTerminatorOp : TEST_Op<"loop_block_term",
-    [DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface>, Pure,
-     Terminator]> {
+    [DeclareOpInterfaceMethods<RegionBranchTerminatorOpInterface,
+        ["getMutableSuccessorOperands"]>,
+     Pure, Terminator]> {
   let arguments = (ins I32:$nextIterArg, F32:$exitArg);
 
   let assemblyFormat = [{