[flang-commits] [flang] [flang] Lower REDUCE intrinsic with no DIM argument and rank 1 (PR #94652)

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

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@@ -5705,7 +5705,63 @@ void IntrinsicLibrary::genRandomSeed(llvm::ArrayRef<fir::ExtendedValue> args) {
 fir::ExtendedValue
 IntrinsicLibrary::genReduce(mlir::Type resultType,
                             llvm::ArrayRef<fir::ExtendedValue> args) {
-  TODO(loc, "intrinsic: reduce");
+  assert(args.size() == 6);
+
+  fir::BoxValue arrayTmp = builder.createBox(loc, args[0]);
+  mlir::Value array = fir::getBase(arrayTmp);
+  mlir::Value operation = fir::getBase(args[1]);
+  int rank = arrayTmp.rank();
+  assert(rank >= 1);
+
+  mlir::Type ty = array.getType();
+  mlir::Type arrTy = fir::dyn_cast_ptrOrBoxEleTy(ty);
+  mlir::Type eleTy = mlir::cast<fir::SequenceType>(arrTy).getEleTy();
+
+  // Handle optional mask argument
+  bool absentDim = isStaticallyAbsent(args[1]);
+
+  auto mask = isStaticallyAbsent(args[3])
+                  ? builder.create<fir::AbsentOp>(
+                        loc, fir::BoxType::get(builder.getI1Type()))
+                  : builder.createBox(loc, args[3]);
+
+  mlir::Value identity =
+      isStaticallyAbsent(args[4])
+          ? builder.create<fir::AbsentOp>(loc, fir::ReferenceType::get(eleTy))
+          : fir::getBase(args[4]);
+
+  mlir::Value ordered = isStaticallyAbsent(args[5])
+                            ? builder.createBool(loc, true)
+                            : fir::getBase(args[5]);
+
+  // We call the type specific versions because the result is scalar
+  // in the case below.
+  if (absentDim || rank == 1) {
+    if (fir::isa_complex(eleTy) || fir::isa_derived(eleTy)) {
+      mlir::Value result = builder.createTemporary(loc, eleTy);
+      fir::runtime::genReduce(builder, loc, array, operation, mask, identity,
+                              ordered, result);
+      if (fir::isa_derived(eleTy))
+        return result;
+      return builder.create<fir::LoadOp>(loc, result);
+    }
+    if (fir::isa_char(eleTy)) {
+      // Create mutable fir.box to be passed to the runtime for the result.
+      fir::MutableBoxValue resultMutableBox =
+          fir::factory::createTempMutableBox(builder, loc, eleTy);
+      mlir::Value resultIrBox =
+          fir::factory::getMutableIRBox(builder, loc, resultMutableBox);
+      fir::runtime::genReduce(builder, loc, array, operation, mask, identity,
+                              ordered, resultIrBox);
+      // Handle cleanup of allocatable result descriptor and return
+      return readAndAddCleanUp(resultMutableBox, resultType, "REDUCE");
+    }
+    auto resultBox = builder.create<fir::AbsentOp>(
+        loc, fir::BoxType::get(builder.getI1Type()));
+    return fir::runtime::genReduce(builder, loc, array, operation, mask,
+                                   identity, ordered, resultBox);
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clementval wrote:

I split this into two functions. One for real, int and logical with the returned value and one for complex, character and derived-type with the result ssa passed as argument. 

https://github.com/llvm/llvm-project/pull/94652