[Mlir-commits] [mlir] 621cbcd - [mlir][acc] Adds attr to acc.present to identify default clause origin (#169114)

[llvmlistbot at llvm.org]

Author: Atmn Patel
Date: 2025-11-24T10:15:00-08:00
New Revision: 621cbcde0161341494b546a1fb478cfd57d1a94f

URL: https://github.com/llvm/llvm-project/commit/621cbcde0161341494b546a1fb478cfd57d1a94f
DIFF: https://github.com/llvm/llvm-project/commit/621cbcde0161341494b546a1fb478cfd57d1a94f.diff

LOG: [mlir][acc] Adds attr to acc.present to identify default clause origin (#169114)

The `acc.present` Op as generated by ACCImplicitData does not provide a
way to differentiate between `acc.present` ops that are generated
implicitly and the ones that are generated as result of an explicit
`default(present)` clause in the source code. This differentiation would
allow for better communication to the user on the decisions made by the
compiler while managing data automatically between the host and the
device. This commit adds this information as a discardable attribute on
the `acc.present` op.

Added: 
    

Modified: 
    flang/test/Transforms/OpenACC/acc-implicit-data.fir
    mlir/include/mlir/Dialect/OpenACC/OpenACC.h
    mlir/lib/Dialect/OpenACC/Transforms/ACCImplicitData.cpp
    mlir/test/Dialect/OpenACC/acc-implicit-data.mlir

Removed: 
    


################################################################################
diff  --git a/flang/test/Transforms/OpenACC/acc-implicit-data.fir b/flang/test/Transforms/OpenACC/acc-implicit-data.fir
index 7f6a57cb4d8c6..2d28c341d0d5e 100644
--- a/flang/test/Transforms/OpenACC/acc-implicit-data.fir
+++ b/flang/test/Transforms/OpenACC/acc-implicit-data.fir
@@ -133,7 +133,7 @@ func.func @test_fir_derivedtype_in_parallel_defaultpresent() {
   return
 }
 
-// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.type<_QFTaggr{field:f32}>>) -> !fir.ref<!fir.type<_QFTaggr{field:f32}>> {implicit = true, name = "aggrvar"}
+// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.type<_QFTaggr{field:f32}>>) -> !fir.ref<!fir.type<_QFTaggr{field:f32}>> {acc.from_default, implicit = true, name = "aggrvar"}
 // CHECK: acc.delete accPtr(%[[PRESENT]] : !fir.ref<!fir.type<_QFTaggr{field:f32}>>) {dataClause = #acc<data_clause acc_present>, implicit = true, name = "aggrvar"}
 
 // -----
@@ -147,7 +147,7 @@ func.func @test_fir_derivedtype_in_kernels_defaultpresent() {
   return
 }
 
-// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.type<_QFTaggr{field:f32}>>) -> !fir.ref<!fir.type<_QFTaggr{field:f32}>> {implicit = true, name = "aggrvar"}
+// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.type<_QFTaggr{field:f32}>>) -> !fir.ref<!fir.type<_QFTaggr{field:f32}>> {acc.from_default, implicit = true, name = "aggrvar"}
 // CHECK: acc.delete accPtr(%[[PRESENT]] : !fir.ref<!fir.type<_QFTaggr{field:f32}>>) {dataClause = #acc<data_clause acc_present>, implicit = true, name = "aggrvar"}
 
 // -----
@@ -161,7 +161,7 @@ func.func @test_fir_array_in_parallel_defaultpresent() {
   return
 }
 
-// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.array<10xf32>>) -> !fir.ref<!fir.array<10xf32>> {implicit = true, name = "arrayvar"}
+// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.array<10xf32>>) -> !fir.ref<!fir.array<10xf32>> {acc.from_default, implicit = true, name = "arrayvar"}
 // CHECK: acc.delete accPtr(%[[PRESENT]] : !fir.ref<!fir.array<10xf32>>) {dataClause = #acc<data_clause acc_present>, implicit = true, name = "arrayvar"}
 
 // -----
@@ -175,7 +175,7 @@ func.func @test_fir_array_in_kernels_defaultpresent() {
   return
 }
 
-// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.array<10xf32>>) -> !fir.ref<!fir.array<10xf32>> {implicit = true, name = "arrayvar"}
+// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : !fir.ref<!fir.array<10xf32>>) -> !fir.ref<!fir.array<10xf32>> {acc.from_default, implicit = true, name = "arrayvar"}
 // CHECK: acc.delete accPtr(%[[PRESENT]] : !fir.ref<!fir.array<10xf32>>) {dataClause = #acc<data_clause acc_present>, implicit = true, name = "arrayvar"}
 
 // -----

diff  --git a/mlir/include/mlir/Dialect/OpenACC/OpenACC.h b/mlir/include/mlir/Dialect/OpenACC/OpenACC.h
index 05d2316711c8a..601fc1a594768 100644
--- a/mlir/include/mlir/Dialect/OpenACC/OpenACC.h
+++ b/mlir/include/mlir/Dialect/OpenACC/OpenACC.h
@@ -177,6 +177,10 @@ static constexpr StringLiteral getRoutineInfoAttrName() {
   return StringLiteral("acc.routine_info");
 }
 
+static constexpr StringLiteral getFromDefaultClauseAttrName() {
+  return StringLiteral("acc.from_default");
+}
+
 static constexpr StringLiteral getVarNameAttrName() {
   return VarNameAttr::name;
 }

diff  --git a/mlir/lib/Dialect/OpenACC/Transforms/ACCImplicitData.cpp b/mlir/lib/Dialect/OpenACC/Transforms/ACCImplicitData.cpp
index 91262bd76ca31..7d729619b3f21 100644
--- a/mlir/lib/Dialect/OpenACC/Transforms/ACCImplicitData.cpp
+++ b/mlir/lib/Dialect/OpenACC/Transforms/ACCImplicitData.cpp
@@ -570,6 +570,8 @@ Operation *ACCImplicitData::generateDataClauseOpForCandidate(
       newDataOp = acc::PresentOp::create(builder, loc, var,
                                          /*structured=*/true, /*implicit=*/true,
                                          accSupport.getVariableName(var));
+      newDataOp->setAttr(acc::getFromDefaultClauseAttrName(),
+                         builder.getUnitAttr());
     } else {
       auto copyinOp =
           acc::CopyinOp::create(builder, loc, var,

diff  --git a/mlir/test/Dialect/OpenACC/acc-implicit-data.mlir b/mlir/test/Dialect/OpenACC/acc-implicit-data.mlir
index cf09c33ca5197..06c1c3cadd4ba 100644
--- a/mlir/test/Dialect/OpenACC/acc-implicit-data.mlir
+++ b/mlir/test/Dialect/OpenACC/acc-implicit-data.mlir
@@ -110,7 +110,7 @@ func.func @test_array_parallel_defaultpresent() {
 }
 
 // CHECK-LABEL: func.func @test_array_parallel_defaultpresent
-// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : memref<10xf32>) -> memref<10xf32> {implicit = true, name = ""}
+// CHECK: %[[PRESENT:.*]] = acc.present varPtr({{.*}} : memref<10xf32>) -> memref<10xf32> {acc.from_default, implicit = true, name = ""}
 // CHECK: acc.delete accPtr(%[[PRESENT]] : memref<10xf32>) {dataClause = #acc<data_clause acc_present>, implicit = true, name = ""}
 
 // -----