[Mlir-commits] [mlir] bd5b293 - [mlir] Support full commutative operation equality (#192652)

[llvmlistbot at llvm.org]

Author: jumerckx
Date: 2026-04-19T11:47:09+02:00
New Revision: bd5b29314660232e74a43b684cbecf6f0c1e3983

URL: https://github.com/llvm/llvm-project/commit/bd5b29314660232e74a43b684cbecf6f0c1e3983
DIFF: https://github.com/llvm/llvm-project/commit/bd5b29314660232e74a43b684cbecf6f0c1e3983.diff

LOG: [mlir] Support full commutative operation equality (#192652)

Previous, commutative equality only works if the operand lists are
exact permutations of one another.
By treating the `equivalentValues` map as a map onto a common set of
values, we can achieve full commutative equality.

Added: 
    

Modified: 
    mlir/lib/IR/OperationSupport.cpp
    mlir/test/Dialect/Func/duplicate-function-elimination.mlir
    mlir/test/IR/operation-equality.mlir

Removed: 
    


################################################################################
diff  --git a/mlir/lib/IR/OperationSupport.cpp b/mlir/lib/IR/OperationSupport.cpp
index 91c62a6604c16..32c6426429ae8 100644
--- a/mlir/lib/IR/OperationSupport.cpp
+++ b/mlir/lib/IR/OperationSupport.cpp
@@ -791,11 +791,12 @@ struct ValueEquivalenceCache {
     if (lhsIt == lhsRange.end())
       return success();
 
-    // Handle another simple case where operands are just a permutation.
-    // Note: This is not sufficient, this handles simple cases relatively
-    // cheaply.
-    auto sortValues = [](ValueRange values) {
-      SmallVector<Value> sortedValues = llvm::to_vector(values);
+    // Replace values with their entry in equivalentValues if they're in there
+    // that way, a sorted pointer comparison is enough to determine
+    // commutativity.
+    auto sortValues = [this](ValueRange values) {
+      SmallVector<Value> sortedValues = llvm::map_to_vector(
+          values, [this](Value a) { return equivalentValues.lookup_or(a, a); });
       llvm::sort(sortedValues, [](Value a, Value b) {
         return a.getAsOpaquePointer() < b.getAsOpaquePointer();
       });

diff  --git a/mlir/test/Dialect/Func/duplicate-function-elimination.mlir b/mlir/test/Dialect/Func/duplicate-function-elimination.mlir
index bc04e8fa9cd23..4d00d8a954d17 100644
--- a/mlir/test/Dialect/Func/duplicate-function-elimination.mlir
+++ b/mlir/test/Dialect/Func/duplicate-function-elimination.mlir
@@ -58,11 +58,10 @@ func.func @user(%arg0: f32, %arg1: f32) -> f32 {
 
 // CHECK:     @add_lr
 // CHECK-NOT: @also_add_lr
-// CHECK:     @add_rl
+// CHECK-NOT:     @add_rl
 // CHECK-NOT: @also_add_rl
 // CHECK:     @user
-// CHECK-2:     call @add_lr
-// CHECK-2:     call @add_rl
+// CHECK-4:     call @add_lr
 
 // -----
 

diff  --git a/mlir/test/IR/operation-equality.mlir b/mlir/test/IR/operation-equality.mlir
index 405701aafb127..ed51b610fbc46 100644
--- a/mlir/test/IR/operation-equality.mlir
+++ b/mlir/test/IR/operation-equality.mlir
@@ -214,3 +214,31 @@ builtin.module attributes {test.includes_setup} {
     arith.addi %0#1, %0#0 : i32
   }) { ignore_commutativity } : () -> ()
 }
+
+// -----
+
+// CHECK-LABEL: test.commutatively_equal
+// CHECK-SAME: compares equals
+
+"test.commutatively_equal"() ({
+  ^bb0(%arg0 : i32, %arg1 : i32):
+    arith.addi %arg0, %arg1 : i32
+  }) : () -> ()
+"test.commutatively_equal"() ({
+  ^bb0(%arg0 : i32, %arg1 : i32):
+    arith.addi %arg1, %arg0 : i32
+  }) : () -> ()
+
+// -----
+
+// CHECK-LABEL: test.ignore_commutatively_equal
+// CHECK-SAME: compares NOT equals
+
+"test.ignore_commutatively_equal"() ({
+  ^bb0(%arg0 : i32, %arg1 : i32):
+    arith.addi %arg0, %arg1 : i32
+  }) { ignore_commutativity } : () -> ()
+"test.ignore_commutatively_equal"() ({
+  ^bb0(%arg0 : i32, %arg1 : i32):
+    arith.addi %arg1, %arg0 : i32
+  }) { ignore_commutativity } : () -> ()