llvm-project/flang/runtime/extrema.cpp

682 lines
25 KiB
C++

//===-- runtime/extrema.cpp -----------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
// Implements MAXLOC, MINLOC, MAXVAL, & MINVAL for all required operand types
// and shapes and (for MAXLOC & MINLOC) result integer kinds. Also implements
// NORM2 using common infrastructure.
#include "reduction-templates.h"
#include "flang/Common/long-double.h"
#include "flang/Runtime/character.h"
#include "flang/Runtime/reduction.h"
#include <algorithm>
#include <cinttypes>
#include <cmath>
#include <optional>
namespace Fortran::runtime {
// MAXLOC & MINLOC
template <typename T, bool IS_MAX, bool BACK> struct NumericCompare {
using Type = T;
explicit NumericCompare(std::size_t /*elemLen; ignored*/) {}
bool operator()(const T &value, const T &previous) const {
if (value == previous) {
return BACK;
} else if constexpr (IS_MAX) {
return value > previous;
} else {
return value < previous;
}
}
};
template <typename T, bool IS_MAX, bool BACK> class CharacterCompare {
public:
using Type = T;
explicit CharacterCompare(std::size_t elemLen)
: chars_{elemLen / sizeof(T)} {}
bool operator()(const T &value, const T &previous) const {
int cmp{CharacterScalarCompare<T>(&value, &previous, chars_, chars_)};
if (cmp == 0) {
return BACK;
} else if constexpr (IS_MAX) {
return cmp > 0;
} else {
return cmp < 0;
}
}
private:
std::size_t chars_;
};
template <typename COMPARE> class ExtremumLocAccumulator {
public:
using Type = typename COMPARE::Type;
ExtremumLocAccumulator(const Descriptor &array, std::size_t chars = 0)
: array_{array}, argRank_{array.rank()}, compare_{array.ElementBytes()} {
Reinitialize();
}
void Reinitialize() {
// per standard: result indices are all zero if no data
for (int j{0}; j < argRank_; ++j) {
extremumLoc_[j] = 0;
}
previous_ = nullptr;
}
int argRank() const { return argRank_; }
template <typename A> void GetResult(A *p, int zeroBasedDim = -1) {
if (zeroBasedDim >= 0) {
*p = extremumLoc_[zeroBasedDim] -
array_.GetDimension(zeroBasedDim).LowerBound() + 1;
} else {
for (int j{0}; j < argRank_; ++j) {
p[j] = extremumLoc_[j] - array_.GetDimension(j).LowerBound() + 1;
}
}
}
template <typename IGNORED> bool AccumulateAt(const SubscriptValue at[]) {
const auto &value{*array_.Element<Type>(at)};
if (!previous_ || compare_(value, *previous_)) {
previous_ = &value;
for (int j{0}; j < argRank_; ++j) {
extremumLoc_[j] = at[j];
}
}
return true;
}
private:
const Descriptor &array_;
int argRank_;
SubscriptValue extremumLoc_[maxRank];
const Type *previous_{nullptr};
COMPARE compare_;
};
template <typename ACCUMULATOR, typename CPPTYPE>
static void LocationHelper(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, const Descriptor *mask,
Terminator &terminator) {
ACCUMULATOR accumulator{x};
DoTotalReduction<CPPTYPE>(x, 0, mask, accumulator, intrinsic, terminator);
ApplyIntegerKind<LocationResultHelper<ACCUMULATOR>::template Functor, void>(
kind, terminator, accumulator, result);
}
template <TypeCategory CAT, int KIND, bool IS_MAX,
template <typename, bool, bool> class COMPARE>
inline void DoMaxOrMinLoc(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, const char *source, int line,
const Descriptor *mask, bool back) {
using CppType = CppTypeFor<CAT, KIND>;
Terminator terminator{source, line};
if (back) {
LocationHelper<ExtremumLocAccumulator<COMPARE<CppType, IS_MAX, true>>,
CppType>(intrinsic, result, x, kind, mask, terminator);
} else {
LocationHelper<ExtremumLocAccumulator<COMPARE<CppType, IS_MAX, false>>,
CppType>(intrinsic, result, x, kind, mask, terminator);
}
}
template <TypeCategory CAT, bool IS_MAX> struct TypedMaxOrMinLocHelper {
template <int KIND> struct Functor {
void operator()(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, const char *source, int line,
const Descriptor *mask, bool back) const {
DoMaxOrMinLoc<CAT, KIND, IS_MAX, NumericCompare>(
intrinsic, result, x, kind, source, line, mask, back);
}
};
};
template <bool IS_MAX>
inline void TypedMaxOrMinLoc(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, const char *source, int line,
const Descriptor *mask, bool back) {
int rank{x.rank()};
SubscriptValue extent[1]{rank};
result.Establish(TypeCategory::Integer, kind, nullptr, 1, extent,
CFI_attribute_allocatable);
result.GetDimension(0).SetBounds(1, extent[0]);
Terminator terminator{source, line};
if (int stat{result.Allocate()}) {
terminator.Crash(
"%s: could not allocate memory for result; STAT=%d", intrinsic, stat);
}
CheckIntegerKind(terminator, kind, intrinsic);
auto catKind{x.type().GetCategoryAndKind()};
RUNTIME_CHECK(terminator, catKind.has_value());
switch (catKind->first) {
case TypeCategory::Integer:
ApplyIntegerKind<
TypedMaxOrMinLocHelper<TypeCategory::Integer, IS_MAX>::template Functor,
void>(catKind->second, terminator, intrinsic, result, x, kind, source,
line, mask, back);
break;
case TypeCategory::Real:
ApplyFloatingPointKind<
TypedMaxOrMinLocHelper<TypeCategory::Real, IS_MAX>::template Functor,
void>(catKind->second, terminator, intrinsic, result, x, kind, source,
line, mask, back);
break;
case TypeCategory::Character:
ApplyCharacterKind<TypedMaxOrMinLocHelper<TypeCategory::Character,
IS_MAX>::template Functor,
void>(catKind->second, terminator, intrinsic, result, x, kind, source,
line, mask, back);
break;
default:
terminator.Crash(
"%s: bad data type code (%d) for array", intrinsic, x.type().raw());
}
}
extern "C" {
void RTNAME(Maxloc)(Descriptor &result, const Descriptor &x, int kind,
const char *source, int line, const Descriptor *mask, bool back) {
TypedMaxOrMinLoc<true>("MAXLOC", result, x, kind, source, line, mask, back);
}
void RTNAME(Minloc)(Descriptor &result, const Descriptor &x, int kind,
const char *source, int line, const Descriptor *mask, bool back) {
TypedMaxOrMinLoc<false>("MINLOC", result, x, kind, source, line, mask, back);
}
} // extern "C"
// MAXLOC/MINLOC with DIM=
template <TypeCategory CAT, int KIND, bool IS_MAX,
template <typename, bool, bool> class COMPARE, bool BACK>
static void DoPartialMaxOrMinLocDirection(const char *intrinsic,
Descriptor &result, const Descriptor &x, int kind, int dim,
const Descriptor *mask, Terminator &terminator) {
using CppType = CppTypeFor<CAT, KIND>;
using Accumulator = ExtremumLocAccumulator<COMPARE<CppType, IS_MAX, BACK>>;
Accumulator accumulator{x};
ApplyIntegerKind<PartialLocationHelper<Accumulator>::template Functor, void>(
kind, terminator, result, x, dim, mask, terminator, intrinsic,
accumulator);
}
template <TypeCategory CAT, int KIND, bool IS_MAX,
template <typename, bool, bool> class COMPARE>
inline void DoPartialMaxOrMinLoc(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, int dim, const Descriptor *mask, bool back,
Terminator &terminator) {
if (back) {
DoPartialMaxOrMinLocDirection<CAT, KIND, IS_MAX, COMPARE, true>(
intrinsic, result, x, kind, dim, mask, terminator);
} else {
DoPartialMaxOrMinLocDirection<CAT, KIND, IS_MAX, COMPARE, false>(
intrinsic, result, x, kind, dim, mask, terminator);
}
}
template <TypeCategory CAT, bool IS_MAX,
template <typename, bool, bool> class COMPARE>
struct DoPartialMaxOrMinLocHelper {
template <int KIND> struct Functor {
void operator()(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, int dim, const Descriptor *mask,
bool back, Terminator &terminator) const {
DoPartialMaxOrMinLoc<CAT, KIND, IS_MAX, COMPARE>(
intrinsic, result, x, kind, dim, mask, back, terminator);
}
};
};
template <bool IS_MAX>
inline void TypedPartialMaxOrMinLoc(const char *intrinsic, Descriptor &result,
const Descriptor &x, int kind, int dim, const char *source, int line,
const Descriptor *mask, bool back) {
Terminator terminator{source, line};
CheckIntegerKind(terminator, kind, intrinsic);
auto catKind{x.type().GetCategoryAndKind()};
RUNTIME_CHECK(terminator, catKind.has_value());
switch (catKind->first) {
case TypeCategory::Integer:
ApplyIntegerKind<DoPartialMaxOrMinLocHelper<TypeCategory::Integer, IS_MAX,
NumericCompare>::template Functor,
void>(catKind->second, terminator, intrinsic, result, x, kind, dim,
mask, back, terminator);
break;
case TypeCategory::Real:
ApplyFloatingPointKind<DoPartialMaxOrMinLocHelper<TypeCategory::Real,
IS_MAX, NumericCompare>::template Functor,
void>(catKind->second, terminator, intrinsic, result, x, kind, dim,
mask, back, terminator);
break;
case TypeCategory::Character:
ApplyCharacterKind<DoPartialMaxOrMinLocHelper<TypeCategory::Character,
IS_MAX, CharacterCompare>::template Functor,
void>(catKind->second, terminator, intrinsic, result, x, kind, dim,
mask, back, terminator);
break;
default:
terminator.Crash(
"%s: bad data type code (%d) for array", intrinsic, x.type().raw());
}
}
extern "C" {
void RTNAME(MaxlocDim)(Descriptor &result, const Descriptor &x, int kind,
int dim, const char *source, int line, const Descriptor *mask, bool back) {
TypedPartialMaxOrMinLoc<true>(
"MAXLOC", result, x, kind, dim, source, line, mask, back);
}
void RTNAME(MinlocDim)(Descriptor &result, const Descriptor &x, int kind,
int dim, const char *source, int line, const Descriptor *mask, bool back) {
TypedPartialMaxOrMinLoc<false>(
"MINLOC", result, x, kind, dim, source, line, mask, back);
}
} // extern "C"
// MAXVAL and MINVAL
template <TypeCategory CAT, int KIND, bool IS_MAXVAL> struct MaxOrMinIdentity {
using Type = CppTypeFor<CAT, KIND>;
static constexpr Type Value() {
return IS_MAXVAL ? std::numeric_limits<Type>::lowest()
: std::numeric_limits<Type>::max();
}
};
// std::numeric_limits<> may not know int128_t
template <bool IS_MAXVAL>
struct MaxOrMinIdentity<TypeCategory::Integer, 16, IS_MAXVAL> {
using Type = CppTypeFor<TypeCategory::Integer, 16>;
static constexpr Type Value() {
return IS_MAXVAL ? Type{1} << 127 : ~Type{0} >> 1;
}
};
template <TypeCategory CAT, int KIND, bool IS_MAXVAL>
class NumericExtremumAccumulator {
public:
using Type = CppTypeFor<CAT, KIND>;
explicit NumericExtremumAccumulator(const Descriptor &array)
: array_{array} {}
void Reinitialize() {
extremum_ = MaxOrMinIdentity<CAT, KIND, IS_MAXVAL>::Value();
}
template <typename A> void GetResult(A *p, int /*zeroBasedDim*/ = -1) const {
*p = extremum_;
}
bool Accumulate(Type x) {
if constexpr (IS_MAXVAL) {
if (x > extremum_) {
extremum_ = x;
}
} else if (x < extremum_) {
extremum_ = x;
}
return true;
}
template <typename A> bool AccumulateAt(const SubscriptValue at[]) {
return Accumulate(*array_.Element<A>(at));
}
private:
const Descriptor &array_;
Type extremum_{MaxOrMinIdentity<CAT, KIND, IS_MAXVAL>::Value()};
};
template <TypeCategory CAT, int KIND, bool IS_MAXVAL>
inline CppTypeFor<CAT, KIND> TotalNumericMaxOrMin(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask,
const char *intrinsic) {
return GetTotalReduction<CAT, KIND>(x, source, line, dim, mask,
NumericExtremumAccumulator<CAT, KIND, IS_MAXVAL>{x}, intrinsic);
}
template <TypeCategory CAT, int KIND, typename ACCUMULATOR>
static void DoMaxMinNorm2(Descriptor &result, const Descriptor &x, int dim,
const Descriptor *mask, const char *intrinsic, Terminator &terminator) {
using Type = CppTypeFor<CAT, KIND>;
ACCUMULATOR accumulator{x};
if (dim == 0 || x.rank() == 1) {
// Total reduction
result.Establish(x.type(), x.ElementBytes(), nullptr, 0, nullptr,
CFI_attribute_allocatable);
if (int stat{result.Allocate()}) {
terminator.Crash(
"%s: could not allocate memory for result; STAT=%d", intrinsic, stat);
}
DoTotalReduction<Type>(x, dim, mask, accumulator, intrinsic, terminator);
accumulator.GetResult(result.OffsetElement<Type>());
} else {
// Partial reduction
PartialReduction<ACCUMULATOR, CAT, KIND>(
result, x, dim, mask, terminator, intrinsic, accumulator);
}
}
template <TypeCategory CAT, bool IS_MAXVAL> struct MaxOrMinHelper {
template <int KIND> struct Functor {
void operator()(Descriptor &result, const Descriptor &x, int dim,
const Descriptor *mask, const char *intrinsic,
Terminator &terminator) const {
DoMaxMinNorm2<CAT, KIND,
NumericExtremumAccumulator<CAT, KIND, IS_MAXVAL>>(
result, x, dim, mask, intrinsic, terminator);
}
};
};
template <bool IS_MAXVAL>
inline void NumericMaxOrMin(Descriptor &result, const Descriptor &x, int dim,
const char *source, int line, const Descriptor *mask,
const char *intrinsic) {
Terminator terminator{source, line};
auto type{x.type().GetCategoryAndKind()};
RUNTIME_CHECK(terminator, type);
switch (type->first) {
case TypeCategory::Integer:
ApplyIntegerKind<
MaxOrMinHelper<TypeCategory::Integer, IS_MAXVAL>::template Functor,
void>(
type->second, terminator, result, x, dim, mask, intrinsic, terminator);
break;
case TypeCategory::Real:
ApplyFloatingPointKind<
MaxOrMinHelper<TypeCategory::Real, IS_MAXVAL>::template Functor, void>(
type->second, terminator, result, x, dim, mask, intrinsic, terminator);
break;
default:
terminator.Crash("%s: bad type code %d", intrinsic, x.type().raw());
}
}
template <int KIND, bool IS_MAXVAL> class CharacterExtremumAccumulator {
public:
using Type = CppTypeFor<TypeCategory::Character, KIND>;
explicit CharacterExtremumAccumulator(const Descriptor &array)
: array_{array}, charLen_{array_.ElementBytes() / KIND} {}
void Reinitialize() { extremum_ = nullptr; }
template <typename A> void GetResult(A *p, int /*zeroBasedDim*/ = -1) const {
static_assert(std::is_same_v<A, Type>);
if (extremum_) {
std::memcpy(p, extremum_, charLen_);
} else {
// empty array: result is all zero-valued characters
std::memset(p, 0, charLen_);
}
}
bool Accumulate(const Type *x) {
if (!extremum_) {
extremum_ = x;
} else {
int cmp{CharacterScalarCompare(x, extremum_, charLen_, charLen_)};
if (IS_MAXVAL == (cmp > 0)) {
extremum_ = x;
}
}
return true;
}
template <typename A> bool AccumulateAt(const SubscriptValue at[]) {
return Accumulate(array_.Element<A>(at));
}
private:
const Descriptor &array_;
std::size_t charLen_;
const Type *extremum_{nullptr};
};
template <bool IS_MAXVAL> struct CharacterMaxOrMinHelper {
template <int KIND> struct Functor {
void operator()(Descriptor &result, const Descriptor &x, int dim,
const Descriptor *mask, const char *intrinsic,
Terminator &terminator) const {
DoMaxMinNorm2<TypeCategory::Character, KIND,
CharacterExtremumAccumulator<KIND, IS_MAXVAL>>(
result, x, dim, mask, intrinsic, terminator);
}
};
};
template <bool IS_MAXVAL>
inline void CharacterMaxOrMin(Descriptor &result, const Descriptor &x, int dim,
const char *source, int line, const Descriptor *mask,
const char *intrinsic) {
Terminator terminator{source, line};
auto type{x.type().GetCategoryAndKind()};
RUNTIME_CHECK(terminator, type && type->first == TypeCategory::Character);
ApplyCharacterKind<CharacterMaxOrMinHelper<IS_MAXVAL>::template Functor,
void>(
type->second, terminator, result, x, dim, mask, intrinsic, terminator);
}
extern "C" {
CppTypeFor<TypeCategory::Integer, 1> RTNAME(MaxvalInteger1)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 1, true>(
x, source, line, dim, mask, "MAXVAL");
}
CppTypeFor<TypeCategory::Integer, 2> RTNAME(MaxvalInteger2)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 2, true>(
x, source, line, dim, mask, "MAXVAL");
}
CppTypeFor<TypeCategory::Integer, 4> RTNAME(MaxvalInteger4)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 4, true>(
x, source, line, dim, mask, "MAXVAL");
}
CppTypeFor<TypeCategory::Integer, 8> RTNAME(MaxvalInteger8)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 8, true>(
x, source, line, dim, mask, "MAXVAL");
}
#ifdef __SIZEOF_INT128__
CppTypeFor<TypeCategory::Integer, 16> RTNAME(MaxvalInteger16)(
const Descriptor &x, const char *source, int line, int dim,
const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 16, true>(
x, source, line, dim, mask, "MAXVAL");
}
#endif
// TODO: REAL(2 & 3)
CppTypeFor<TypeCategory::Real, 4> RTNAME(MaxvalReal4)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 4, true>(
x, source, line, dim, mask, "MAXVAL");
}
CppTypeFor<TypeCategory::Real, 8> RTNAME(MaxvalReal8)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 8, true>(
x, source, line, dim, mask, "MAXVAL");
}
#if LONG_DOUBLE == 80
CppTypeFor<TypeCategory::Real, 10> RTNAME(MaxvalReal10)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 10, true>(
x, source, line, dim, mask, "MAXVAL");
}
#elif LONG_DOUBLE == 128
CppTypeFor<TypeCategory::Real, 16> RTNAME(MaxvalReal16)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 16, true>(
x, source, line, dim, mask, "MAXVAL");
}
#endif
void RTNAME(MaxvalCharacter)(Descriptor &result, const Descriptor &x,
const char *source, int line, const Descriptor *mask) {
CharacterMaxOrMin<true>(result, x, 0, source, line, mask, "MAXVAL");
}
CppTypeFor<TypeCategory::Integer, 1> RTNAME(MinvalInteger1)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 1, false>(
x, source, line, dim, mask, "MINVAL");
}
CppTypeFor<TypeCategory::Integer, 2> RTNAME(MinvalInteger2)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 2, false>(
x, source, line, dim, mask, "MINVAL");
}
CppTypeFor<TypeCategory::Integer, 4> RTNAME(MinvalInteger4)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 4, false>(
x, source, line, dim, mask, "MINVAL");
}
CppTypeFor<TypeCategory::Integer, 8> RTNAME(MinvalInteger8)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 8, false>(
x, source, line, dim, mask, "MINVAL");
}
#ifdef __SIZEOF_INT128__
CppTypeFor<TypeCategory::Integer, 16> RTNAME(MinvalInteger16)(
const Descriptor &x, const char *source, int line, int dim,
const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Integer, 16, false>(
x, source, line, dim, mask, "MINVAL");
}
#endif
// TODO: REAL(2 & 3)
CppTypeFor<TypeCategory::Real, 4> RTNAME(MinvalReal4)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 4, false>(
x, source, line, dim, mask, "MINVAL");
}
CppTypeFor<TypeCategory::Real, 8> RTNAME(MinvalReal8)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 8, false>(
x, source, line, dim, mask, "MINVAL");
}
#if LONG_DOUBLE == 80
CppTypeFor<TypeCategory::Real, 10> RTNAME(MinvalReal10)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 10, false>(
x, source, line, dim, mask, "MINVAL");
}
#elif LONG_DOUBLE == 128
CppTypeFor<TypeCategory::Real, 16> RTNAME(MinvalReal16)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return TotalNumericMaxOrMin<TypeCategory::Real, 16, false>(
x, source, line, dim, mask, "MINVAL");
}
#endif
void RTNAME(MinvalCharacter)(Descriptor &result, const Descriptor &x,
const char *source, int line, const Descriptor *mask) {
CharacterMaxOrMin<false>(result, x, 0, source, line, mask, "MINVAL");
}
void RTNAME(MaxvalDim)(Descriptor &result, const Descriptor &x, int dim,
const char *source, int line, const Descriptor *mask) {
if (x.type().IsCharacter()) {
CharacterMaxOrMin<true>(result, x, dim, source, line, mask, "MAXVAL");
} else {
NumericMaxOrMin<true>(result, x, dim, source, line, mask, "MAXVAL");
}
}
void RTNAME(MinvalDim)(Descriptor &result, const Descriptor &x, int dim,
const char *source, int line, const Descriptor *mask) {
if (x.type().IsCharacter()) {
CharacterMaxOrMin<false>(result, x, dim, source, line, mask, "MINVAL");
} else {
NumericMaxOrMin<false>(result, x, dim, source, line, mask, "MINVAL");
}
}
} // extern "C"
// NORM2
template <int KIND> class Norm2Accumulator {
public:
using Type = CppTypeFor<TypeCategory::Real, KIND>;
// Use at least double precision for accumulators
using AccumType = CppTypeFor<TypeCategory::Real, std::max(KIND, 8)>;
explicit Norm2Accumulator(const Descriptor &array) : array_{array} {}
void Reinitialize() { max_ = sum_ = 0; }
template <typename A> void GetResult(A *p, int /*zeroBasedDim*/ = -1) const {
// m * sqrt(1 + sum((others(:)/m)**2))
*p = static_cast<Type>(max_ * std::sqrt(1 + sum_));
}
bool Accumulate(Type x) {
auto absX{AccumType{std::abs(x)}};
if (!max_) {
max_ = x;
} else if (absX > max_) {
auto t{max_ / absX}; // < 1.0
auto tsq{t * t};
sum_ *= tsq; // scale sum to reflect change to the max
sum_ += tsq; // include a term for the previous max
max_ = absX;
} else { // absX <= max_
auto t{absX / max_};
sum_ += t * t;
}
return true;
}
template <typename A> bool AccumulateAt(const SubscriptValue at[]) {
return Accumulate(*array_.Element<A>(at));
}
private:
const Descriptor &array_;
AccumType max_{0}; // value (m) with largest magnitude
AccumType sum_{0}; // sum((others(:)/m)**2)
};
template <int KIND> struct Norm2Helper {
void operator()(Descriptor &result, const Descriptor &x, int dim,
const Descriptor *mask, Terminator &terminator) const {
DoMaxMinNorm2<TypeCategory::Real, KIND, Norm2Accumulator<KIND>>(
result, x, dim, mask, "NORM2", terminator);
}
};
extern "C" {
// TODO: REAL(2 & 3)
CppTypeFor<TypeCategory::Real, 4> RTNAME(Norm2_4)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return GetTotalReduction<TypeCategory::Real, 4>(
x, source, line, dim, mask, Norm2Accumulator<4>{x}, "NORM2");
}
CppTypeFor<TypeCategory::Real, 8> RTNAME(Norm2_8)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return GetTotalReduction<TypeCategory::Real, 8>(
x, source, line, dim, mask, Norm2Accumulator<8>{x}, "NORM2");
}
#if LONG_DOUBLE == 80
CppTypeFor<TypeCategory::Real, 10> RTNAME(Norm2_10)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return GetTotalReduction<TypeCategory::Real, 10>(
x, source, line, dim, mask, Norm2Accumulator<10>{x}, "NORM2");
}
#elif LONG_DOUBLE == 128
CppTypeFor<TypeCategory::Real, 16> RTNAME(Norm2_16)(const Descriptor &x,
const char *source, int line, int dim, const Descriptor *mask) {
return GetTotalReduction<TypeCategory::Real, 16>(
x, source, line, dim, mask, Norm2Accumulator<16>{x}, "NORM2");
}
#endif
void RTNAME(Norm2Dim)(Descriptor &result, const Descriptor &x, int dim,
const char *source, int line, const Descriptor *mask) {
Terminator terminator{source, line};
auto type{x.type().GetCategoryAndKind()};
RUNTIME_CHECK(terminator, type);
if (type->first == TypeCategory::Real) {
ApplyFloatingPointKind<Norm2Helper, void>(
type->second, terminator, result, x, dim, mask, terminator);
} else {
terminator.Crash("NORM2: bad type code %d", x.type().raw());
}
}
} // extern "C"
} // namespace Fortran::runtime