[flang-commits] [flang] [Flang][OpenMP] Move char box bounds generation for Maps to DirectiveCommons.h (PR #165918)

[via flang-commits]

https://github.com/agozillon created https://github.com/llvm/llvm-project/pull/165918

Currently we generate these bounds in the MapInfoFinalization.cpp pass as it seems there's a missing case for character strings/arrays (length parameter) in the DirectiveCommons bounds generation functionality OpenMP uses for it's map operations.

This PR tries to add this case to the DirectiveCommons function and remove the need for the bounds generation in the MapInfoFinalization pass, so that we are generating the bounds in the same place most other bounds are generated.

>From 6c87cd2aa17b3898cf4b45b764e31c49618fd445 Mon Sep 17 00:00:00 2001
From: agozillon <Andrew.Gozillon at amd.com>
Date: Fri, 31 Oct 2025 15:24:35 -0500
Subject: [PATCH] [Flang][OpenMP] Move char box bounds generation for Maps to
 DirectiveCommons.h

Currently we generate these bounds in the MapInfoFinalization.cpp pass as it seems
there's a missing case for character strings/arrays (length parameter) in the
DirectiveCommons bounds generation functionality OpenMP uses for it's map
operations.

This PR tries to add this case to the DirectiveCommons function and remove the
need for the bounds generation in the MapInfoFinalization pass, so that we are
generating the bounds in the same place most other bounds are generated.
---
 flang/include/flang/Lower/DirectivesCommon.h  | 12 +++++--
 .../Optimizer/OpenMP/MapInfoFinalization.cpp  | 32 -------------------
 2 files changed, 10 insertions(+), 34 deletions(-)

diff --git a/flang/include/flang/Lower/DirectivesCommon.h b/flang/include/flang/Lower/DirectivesCommon.h
index 2d6906738773a..b564ee1f64423 100644
--- a/flang/include/flang/Lower/DirectivesCommon.h
+++ b/flang/include/flang/Lower/DirectivesCommon.h
@@ -512,11 +512,19 @@ fir::factory::AddrAndBoundsInfo gatherDataOperandAddrAndBounds(
       }
       bool dataExvIsAssumedSize =
           Fortran::semantics::IsAssumedSizeArray(symRef->get().GetUltimate());
-      if (genDefaultBounds &&
-          mlir::isa<fir::SequenceType>(fir::unwrapRefType(info.addr.getType())))
+      if (genDefaultBounds && mlir::isa<fir::SequenceType>(
+                                  fir::unwrapRefType(info.addr.getType()))) {
         bounds = fir::factory::genBaseBoundsOps<BoundsOp, BoundsType>(
             builder, operandLocation, dataExv, dataExvIsAssumedSize,
             strideIncludeLowerExtent);
+      }
+      if (genDefaultBounds && fir::characterWithDynamicLen(
+                                  fir::unwrapRefType(info.addr.getType())) ||
+          mlir::isa<fir::BoxCharType>(
+              fir::unwrapRefType(info.addr.getType()))) {
+        bounds = {fir::factory::genBoundsOpFromBoxChar<BoundsOp, BoundsType>(
+            builder, operandLocation, dataExv, info)};
+      }
       asFortran << symRef->get().name().ToString();
     } else { // Unsupported
       llvm::report_fatal_error("Unsupported type of OpenACC operand");
diff --git a/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp b/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp
index bd07d7fe01b85..32faada7a3b49 100644
--- a/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp
+++ b/flang/lib/Optimizer/OpenMP/MapInfoFinalization.cpp
@@ -987,38 +987,6 @@ class MapInfoFinalizationPass
       localBoxAllocas.clear();
       deferrableDesc.clear();
 
-      // First, walk `omp.map.info` ops to see if any of them have varPtrs
-      // with an underlying type of fir.char<k, ?>, i.e a character
-      // with dynamic length. If so, check if they need bounds added.
-      func->walk([&](mlir::omp::MapInfoOp op) {
-        if (!op.getBounds().empty())
-          return;
-
-        mlir::Value varPtr = op.getVarPtr();
-        mlir::Type underlyingVarType = fir::unwrapRefType(varPtr.getType());
-
-        if (!fir::characterWithDynamicLen(underlyingVarType))
-          return;
-
-        fir::factory::AddrAndBoundsInfo info =
-            fir::factory::getDataOperandBaseAddr(
-                builder, varPtr, /*isOptional=*/false, varPtr.getLoc());
-
-        fir::ExtendedValue extendedValue =
-            hlfir::translateToExtendedValue(varPtr.getLoc(), builder,
-                                            hlfir::Entity{info.addr},
-                                            /*continguousHint=*/true)
-                .first;
-        builder.setInsertionPoint(op);
-        llvm::SmallVector<mlir::Value> boundsOps =
-            fir::factory::genImplicitBoundsOps<mlir::omp::MapBoundsOp,
-                                               mlir::omp::MapBoundsType>(
-                builder, info, extendedValue,
-                /*dataExvIsAssumedSize=*/false, varPtr.getLoc());
-
-        op.getBoundsMutable().append(boundsOps);
-      });
-
       // Next, walk `omp.map.info` ops to see if any record members should be
       // implicitly mapped.
       func->walk([&](mlir::omp::MapInfoOp op) {