[flang-commits] [flang] [flang][openacc] Do not loose attributes on folding (PR #80516)

[Valentin Clement バレンタイン クレメン via flang-commits]

https://github.com/clementval created https://github.com/llvm/llvm-project/pull/80516

hlfir.declare introduce some boxes that can be later optimized away. The OpenACC lowering is currently setting some attributes on FIR operations to track declare variables. When the boxes are optimized away these attributes are lost. This patch propagate OpenACC attributes from box_addr op to the defining op of the folding result. 

>From b62ee801d5e6174648dd06e0f07014197c34358d Mon Sep 17 00:00:00 2001
From: Valentin Clement <clementval at gmail.com>
Date: Fri, 2 Feb 2024 16:15:02 -0800
Subject: [PATCH] [flang][openacc] Do not loose attributes on folding

---
 flang/lib/Optimizer/Dialect/FIROps.cpp        | 17 +++++++-
 .../Fir/OpenACC/propagate-attr-folding.fir    | 39 +++++++++++++++++++
 2 files changed, 55 insertions(+), 1 deletion(-)
 create mode 100644 flang/test/Fir/OpenACC/propagate-attr-folding.fir

diff --git a/flang/lib/Optimizer/Dialect/FIROps.cpp b/flang/lib/Optimizer/Dialect/FIROps.cpp
index f826f2566b897..96a676149203d 100644
--- a/flang/lib/Optimizer/Dialect/FIROps.cpp
+++ b/flang/lib/Optimizer/Dialect/FIROps.cpp
@@ -20,6 +20,7 @@
 #include "flang/Optimizer/Support/Utils.h"
 #include "mlir/Dialect/CommonFolders.h"
 #include "mlir/Dialect/Func/IR/FuncOps.h"
+#include "mlir/Dialect/OpenACC/OpenACC.h"
 #include "mlir/Dialect/OpenMP/OpenMPDialect.h"
 #include "mlir/IR/Attributes.h"
 #include "mlir/IR/BuiltinAttributes.h"
@@ -36,6 +37,18 @@ namespace {
 #include "flang/Optimizer/Dialect/CanonicalizationPatterns.inc"
 } // namespace
 
+static void propagateAttributes(mlir::Operation *fromOp,
+                                mlir::Operation *toOp) {
+  if (!fromOp || !toOp)
+    return;
+
+  for (mlir::NamedAttribute attr : fromOp->getAttrs()) {
+    if (attr.getName().str().rfind(
+            mlir::acc::OpenACCDialect::getDialectNamespace(), 0) == 0)
+      toOp->setAttr(attr.getName().str(), attr.getValue());
+  }
+}
+
 /// Return true if a sequence type is of some incomplete size or a record type
 /// is malformed or contains an incomplete sequence type. An incomplete sequence
 /// type is one with more unknown extents in the type than have been provided
@@ -626,8 +639,10 @@ mlir::OpFoldResult fir::BoxAddrOp::fold(FoldAdaptor adaptor) {
   if (auto *v = getVal().getDefiningOp()) {
     if (auto box = mlir::dyn_cast<fir::EmboxOp>(v)) {
       // Fold only if not sliced
-      if (!box.getSlice() && box.getMemref().getType() == getType())
+      if (!box.getSlice() && box.getMemref().getType() == getType()) {
+        propagateAttributes(getOperation(), box.getMemref().getDefiningOp());
         return box.getMemref();
+      }
     }
     if (auto box = mlir::dyn_cast<fir::EmboxCharOp>(v))
       if (box.getMemref().getType() == getType())
diff --git a/flang/test/Fir/OpenACC/propagate-attr-folding.fir b/flang/test/Fir/OpenACC/propagate-attr-folding.fir
new file mode 100644
index 0000000000000..f84269f5fef26
--- /dev/null
+++ b/flang/test/Fir/OpenACC/propagate-attr-folding.fir
@@ -0,0 +1,39 @@
+// RUN: fir-opt %s --opt-bufferization | FileCheck %s 
+
+// Check that OpenACC attributes are propagated to the defining operations when
+// fir.box_addr is folded in bufferization optimization.
+
+func.func @_QPsub1(%arg0: !fir.ref<!fir.array<?x?xf32>> {fir.bindc_name = "a"}, %arg1: !fir.ref<i32> {fir.bindc_name = "n1"}, %arg2: !fir.ref<i32> {fir.bindc_name = "n2"}) {
+  %c1 = arith.constant 1 : index
+  %c0 = arith.constant 0 : index
+  %0 = fir.declare %arg1 {uniq_name = "_QFsub1En1"} : (!fir.ref<i32>) -> !fir.ref<i32>
+  %1 = fir.declare %arg2 {uniq_name = "_QFsub1En2"} : (!fir.ref<i32>) -> !fir.ref<i32>
+  %2 = fir.load %0 : !fir.ref<i32>
+  %3 = fir.convert %2 : (i32) -> index
+  %4 = arith.cmpi sgt, %3, %c0 : index
+  %5 = arith.select %4, %3, %c0 : index
+  %6 = fir.load %1 : !fir.ref<i32>
+  %7 = fir.convert %6 : (i32) -> index
+  %8 = arith.cmpi sgt, %7, %c0 : index
+  %9 = arith.select %8, %7, %c0 : index
+  %10 = fir.shape %5, %9 : (index, index) -> !fir.shape<2>
+  %11 = fir.declare %arg0(%10) {acc.declare = #acc.declare<dataClause =  acc_present>, uniq_name = "_QFsub1Ea"} : (!fir.ref<!fir.array<?x?xf32>>, !fir.shape<2>) -> !fir.ref<!fir.array<?x?xf32>>
+  %12 = fir.embox %11(%10) : (!fir.ref<!fir.array<?x?xf32>>, !fir.shape<2>) -> !fir.box<!fir.array<?x?xf32>>
+  %13:3 = fir.box_dims %12, %c0 : (!fir.box<!fir.array<?x?xf32>>, index) -> (index, index, index)
+  %14 = arith.subi %13#1, %c1 : index
+  %15 = acc.bounds lowerbound(%c0 : index) upperbound(%14 : index) extent(%13#1 : index) stride(%13#2 : index) startIdx(%c1 : index) {strideInBytes = true}
+  %16 = arith.muli %13#2, %13#1 : index
+  %17:3 = fir.box_dims %12, %c1 : (!fir.box<!fir.array<?x?xf32>>, index) -> (index, index, index)
+  %18 = arith.subi %17#1, %c1 : index
+  %19 = acc.bounds lowerbound(%c0 : index) upperbound(%18 : index) extent(%17#1 : index) stride(%16 : index) startIdx(%c1 : index) {strideInBytes = true}
+  %20 = acc.present varPtr(%11 : !fir.ref<!fir.array<?x?xf32>>) bounds(%15, %19) -> !fir.ref<!fir.array<?x?xf32>> {name = "a"}
+  %21 = acc.declare_enter dataOperands(%20 : !fir.ref<!fir.array<?x?xf32>>)
+  acc.declare_exit token(%21)
+  return
+}
+
+// CHECK-LABEL: func.func @_QPsub1(
+// CHECK-SAME: %[[ARG0:.*]]: !fir.ref<!fir.array<?x?xf32>> {fir.bindc_name = "a"}
+// CHECK: %[[DECL:.*]] = fir.declare %[[ARG0]](%{{.*}}) {acc.declare = #acc.declare<dataClause =  acc_present>, uniq_name = "_QFsub1Ea"} : (!fir.ref<!fir.array<?x?xf32>>, !fir.shape<2>) -> !fir.ref<!fir.array<?x?xf32>>
+// CHECK: %[[PRES:.*]] = acc.present varPtr(%[[DECL]] : !fir.ref<!fir.array<?x?xf32>>) bounds(%{{.*}}, %{{.*}}) -> !fir.ref<!fir.array<?x?xf32>> {name = "a"}
+// CHECK: %{{.*}} = acc.declare_enter dataOperands(%[[PRES]] : !fir.ref<!fir.array<?x?xf32>>)