[Mlir-commits] [mlir] [mlir][ODS] Reuse collective builders for zero-result ops (NFC) (PR #226059)

[Mehdi Amini]

https://github.com/joker-eph updated https://github.com/llvm/llvm-project/pull/226059

>From 189a2e4c5c8cccceee2226f5388a750a1840ff2f Mon Sep 17 00:00:00 2001
From: Mehdi Amini <joker.eph at gmail.com>
Date: Wed, 23 Sep 2026 08:34:29 -0700
Subject: [PATCH] [mlir][ODS] Reuse collective builders for zero-result ops

Forward the no-result separate-argument builder to its collective
counterpart instead of generating the same operand, attribute, and
region construction twice. This cuts OpenMPDialect.cpp compiler work
by 1.5% and its machine-code text by about 71 KB.

Assisted-by: Codex
(cherry picked from commit b452f58f7c29795f5bcee4426940ac8b80729825)
---
 mlir/test/mlir-tblgen/op-decl-and-defs.td   | 2 ++
 mlir/test/mlir-tblgen/op-operand.td         | 8 ++++++--
 mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp | 9 +++++++++
 3 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/mlir/test/mlir-tblgen/op-decl-and-defs.td b/mlir/test/mlir-tblgen/op-decl-and-defs.td
index 32c4bb88d188b..bd39c4a013ba3 100644
--- a/mlir/test/mlir-tblgen/op-decl-and-defs.td
+++ b/mlir/test/mlir-tblgen/op-decl-and-defs.td
@@ -205,6 +205,8 @@ def NS_BOp : NS_Op<"op_with_no_operand", []> {
 
 // CHECK-LABEL: NS::BOp declarations
 // CHECK: OpTrait::ZeroOperands
+// DEFS-LABEL: void BOp::build(::mlir::OpBuilder &odsBuilder, ::mlir::OperationState &odsState) {
+// DEFS-NEXT:   build(odsBuilder, odsState, ::mlir::TypeRange{});
 
 def NS_COp : NS_Op<"op_with_one_operand", []> {
   let arguments = (ins I32:$operand);
diff --git a/mlir/test/mlir-tblgen/op-operand.td b/mlir/test/mlir-tblgen/op-operand.td
index ab8d721ed5427..95ddf957ee1c5 100644
--- a/mlir/test/mlir-tblgen/op-operand.td
+++ b/mlir/test/mlir-tblgen/op-operand.td
@@ -37,7 +37,9 @@ def OpB : NS_Op<"one_variadic_operand_op", []> {
 // CHECK-LABEL: OpB::build
 // CHECK:         ::mlir::ValueRange input
 // CHECK-NOT:     assert
-// CHECK:         odsState.addOperands(input);
+// CHECK:         build(odsBuilder, odsState, ::mlir::TypeRange{}, input);
+// CHECK-LABEL: OpB::build
+// CHECK:         odsState.addOperands(operands);
 
 def OpD : NS_Op<"mix_variadic_and_normal_inputs_op", [SameVariadicOperandSize]> {
   let arguments = (ins Variadic<AnyTensor>:$input1, AnyTensor:$input2, Variadic<AnyTensor>:$input3);
@@ -55,6 +57,8 @@ def OpD : NS_Op<"mix_variadic_and_normal_inputs_op", [SameVariadicOperandSize]>
 // DECL-NEXT: return ::llvm::cast<::mlir::TypedValue<::mlir::TensorType>>(*getODSOperands(1).begin());
 
 // CHECK-LABEL: OpD::build
-// CHECK-NEXT: odsState.addOperands(input1);
+// CHECK-NEXT: build(odsBuilder, odsState, ::mlir::TypeRange{}, input1, input2, input3);
+// CHECK-LABEL: OpD::build
+// CHECK: odsState.addOperands(input1);
 // CHECK-NEXT: odsState.addOperands(input2);
 // CHECK-NEXT: odsState.addOperands(input3);
diff --git a/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp b/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
index aa9ff159903bc..6bda98d00e50f 100644
--- a/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
+++ b/mlir/tools/mlir-tblgen/OpDefinitionsGen.cpp
@@ -2485,6 +2485,15 @@ void OpEmitter::genSeparateArgParamBuilder() {
     genInlineCreateBody(paramList);
 
     auto &body = m->body();
+    // The no-result builder can reuse the collective builder. Both forms
+    // otherwise emit identical operand, attribute, and region handling.
+    if (paramKind == TypeParamKind::Separate && op.getNumResults() == 0) {
+      body << "  build(odsBuilder, odsState, ::mlir::TypeRange{}";
+      for (const MethodParameter &param : llvm::drop_begin(paramList, 2))
+        body << ", " << param.getName();
+      body << ");\n";
+      return;
+    }
     genCodeForAddingArgAndRegionForBuilder(body, inferredAttributes,
                                            /*isRawValueAttr=*/attrType ==
                                                AttrParamKind::UnwrappedValue);