[flang-commits] [flang] [flang][runtime] Runtime support for REDUCE() (PR #86214)

[via flang-commits]

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+//===-- include/flang/Runtime/reduce.h --------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+// Defines the API for implementations of the transformational intrinsic
+// functionREDUCE(); see F'2023 16.9.173.
+//
+// Similar to the definition of the APIs for SUM(), &c., in reduction.h,
+// there are typed functions here like ReduceInteger4() for total reductions
+// to scalars and void functions like ReduceInteger4Dim() for partial
+// reductions to smaller arrays.
+
+#ifndef FORTRAN_RUNTIME_REDUCE_H_
+#define FORTRAN_RUNTIME_REDUCE_H_
+
+#include "flang/Common/float128.h"
+#include "flang/Common/uint128.h"
+#include "flang/Runtime/cpp-type.h"
+#include "flang/Runtime/entry-names.h"
+#include <complex>
+#include <cstdint>
+
+namespace Fortran::runtime {
+
+class Descriptor;
+
+template <typename T> using ReductionOperation = T (*)(const T *, const T *);
+template <typename CHAR>
+using ReductionCharOperation = void (*)(CHAR *hiddenResult, const CHAR *x,
+    const CHAR *y, std::size_t resultLen, std::size_t xLen, std::size_t yLen);
+using ReductionDerivedTypeOperation = void (*)(
+    void *hiddenResult, const void *x, const void *y);
+
+extern "C" {
+
+std::int8_t RTDECL(ReduceInteger1)(const Descriptor &,
+    ReductionOperation<std::int8_t>, const char *source, int line, int dim = 0,
+    const Descriptor *mask = nullptr, const std::int8_t *identity = nullptr,
+    bool ordered = true);
+void RTDECL(ReduceInteger1Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::int8_t>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const std::int8_t *identity = nullptr,
+    bool ordered = true);
+std::int16_t RTDECL(ReduceInteger2)(const Descriptor &,
+    ReductionOperation<std::int16_t>, const char *source, int line, int dim = 0,
+    const Descriptor *mask = nullptr, const std::int16_t *identity = nullptr,
+    bool ordered = true);
+void RTDECL(ReduceInteger2Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::int16_t>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const std::int16_t *identity = nullptr,
+    bool ordered = true);
+std::int32_t RTDECL(ReduceInteger4)(const Descriptor &,
+    ReductionOperation<std::int32_t>, const char *source, int line, int dim = 0,
+    const Descriptor *mask = nullptr, const std::int32_t *identity = nullptr,
+    bool ordered = true);
+void RTDECL(ReduceInteger4Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::int32_t>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const std::int32_t *identity = nullptr,
+    bool ordered = true);
+std::int64_t RTDECL(ReduceInteger8)(const Descriptor &,
+    ReductionOperation<std::int64_t>, const char *source, int line, int dim = 0,
+    const Descriptor *mask = nullptr, const std::int64_t *identity = nullptr,
+    bool ordered = true);
+void RTDECL(ReduceInteger8Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::int64_t>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const std::int64_t *identity = nullptr,
+    bool ordered = true);
+#ifdef __SIZEOF_INT128__
+common::int128_t RTDECL(ReduceInteger16)(const Descriptor &,
+    ReductionOperation<common::int128_t>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const common::int128_t *identity = nullptr, bool ordered = true);
+void RTDECL(ReduceInteger16Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<common::int128_t>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr,
+    const common::int128_t *identity = nullptr, bool ordered = true);
+#endif
+
+// REAL/COMPLEX(2 & 3) return 32-bit float results for the caller to downconvert
+float RTDECL(ReduceReal2)(const Descriptor &, ReductionOperation<float>,
+    const char *source, int line, int dim = 0, const Descriptor *mask = nullptr,
+    const float *identity = nullptr, bool ordered = true);
+void RTDECL(ReduceReal2Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<float>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const float *identity = nullptr,
+    bool ordered = true);
+float RTDECL(ReduceReal3)(const Descriptor &, ReductionOperation<float>,
+    const char *source, int line, int dim = 0, const Descriptor *mask = nullptr,
+    const float *identity = nullptr, bool ordered = true);
+void RTDECL(ReduceReal3Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<float>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const float *identity = nullptr,
+    bool ordered = true);
+float RTDECL(ReduceReal4)(const Descriptor &, ReductionOperation<float>,
+    const char *source, int line, int dim = 0, const Descriptor *mask = nullptr,
+    const float *identity = nullptr, bool ordered = true);
+void RTDECL(ReduceReal4Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<float>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const float *identity = nullptr,
+    bool ordered = true);
+double RTDECL(ReduceReal8)(const Descriptor &, ReductionOperation<double>,
+    const char *source, int line, int dim = 0, const Descriptor *mask = nullptr,
+    const double *identity = nullptr, bool ordered = true);
+void RTDECL(ReduceReal8Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<double>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const double *identity = nullptr,
+    bool ordered = true);
+#if LDBL_MANT_DIG == 64
+long double RTDECL(ReduceReal10)(const Descriptor &,
+    ReductionOperation<long double>, const char *source, int line, int dim = 0,
+    const Descriptor *mask = nullptr, const long double *identity = nullptr,
+    bool ordered = true);
+void RTDECL(ReduceReal10Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<long double>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const long double *identity = nullptr,
+    bool ordered = true);
+#endif
+#if LDBL_MANT_DIG == 113 || HAS_FLOAT128
+CppFloat128Type RTDECL(ReduceReal16)(const Descriptor &,
+    ReductionOperation<CppFloat128Type>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const CppFloat128Type *identity = nullptr, bool ordered = true);
+void RTDECL(ReduceReal16Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<CppFloat128Type>, const char *source, int line, int dim,
+    const Descriptor *mask = nullptr, const CppFloat128Type *identity = nullptr,
+    bool ordered = true);
+#endif
+
+void RTDECL(CppReduceComplex2)(std::complex<float> &, const Descriptor &,
+    ReductionOperation<std::complex<float>>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const std::complex<float> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex2Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::complex<float>>, const char *source, int line,
+    int dim, const Descriptor *mask = nullptr,
+    const std::complex<float> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex3)(std::complex<float> &, const Descriptor &,
+    ReductionOperation<std::complex<float>>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const std::complex<float> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex3Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::complex<float>>, const char *source, int line,
+    int dim, const Descriptor *mask = nullptr,
+    const std::complex<float> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex4)(std::complex<float> &, const Descriptor &,
+    ReductionOperation<std::complex<float>>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const std::complex<float> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex4Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::complex<float>>, const char *source, int line,
+    int dim, const Descriptor *mask = nullptr,
+    const std::complex<float> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex8)(std::complex<double> &, const Descriptor &,
+    ReductionOperation<std::complex<double>>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const std::complex<double> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex8Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::complex<double>>, const char *source, int line,
+    int dim, const Descriptor *mask = nullptr,
+    const std::complex<double> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex10)(std::complex<long double> &, const Descriptor &,
+    ReductionOperation<std::complex<long double>>, const char *source, int line,
+    int dim = 0, const Descriptor *mask = nullptr,
+    const std::complex<long double> *identity = nullptr, bool ordered = true);
+void RTDECL(CppReduceComplex10Dim)(Descriptor &result, const Descriptor &array,
+    ReductionOperation<std::complex<long double>>, const char *source, int line,
+    int dim, const Descriptor *mask = nullptr,
+    const std::complex<long double> *identity = nullptr, bool ordered = true);
----------------
jeanPerier wrote:

Should it be under "#if LDBL_MANT_DIG == 64" like `ReduceReal10`?

Previous definition are not very consistent. I see `CppProductComplex10` is guarded, but not `CppSumComplex10` in reduction.h for instance. Signatures under ifdef cannot be used by lowering to automatically generate the signature (signature is manually generated in lowering), but it may also be misleading to pretend REAL(10)/COMPLEX(10) version of the runtime are always defined.

https://github.com/llvm/llvm-project/pull/86214