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libsst/Lib/Include/CML/et/array_promotions.h
2026-04-03 00:22:39 -05:00

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/* -*- C++ -*- ------------------------------------------------------------
Copyright (c) 2007 Jesse Anders and Demian Nave http://cmldev.net/
The Configurable Math Library (CML) is distributed under the terms of the
Boost Software License, v1.0 (see cml/LICENSE for details).
*-----------------------------------------------------------------------*/
/** @file
* @brief
*
* Defines promotions between array types.
*
* @todo Can/should an expression with a fixed-size argument promote to a
* fixed array instead of a dynamic array?
*/
#ifndef array_promotions_h
#define array_promotions_h
#include <cml/core/cml_meta.h>
#include <cml/et/scalar_promotions.h>
namespace cml {
namespace et {
#define VAL_MAX(_a_,_b_) ( ((_a_)>(_b_))?(_a_):(_b_) )
namespace detail {
/* This is specialized for 1D and 2D promotions: */
template<class A1, class A2, typename DTag1, typename DTag2,
typename PromotedSizeTag> struct promote;
/* Promote 1D fixed-size arrays to a 1D fixed-size array: */
template<class A1, class A2>
struct promote<A1,A2,oned_tag,oned_tag,fixed_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, deduce the array size: */
enum { Size = VAL_MAX((size_t)A1::array_size, (size_t)A2::array_size) };
/* Finally, generate the promoted array type: */
typedef fixed_1D<promoted_scalar,Size> type;
};
/* Promote 1D dynamic arrays to a 1D dynamic array: */
template<class A1, class A2>
struct promote<A1,A2,oned_tag,oned_tag,dynamic_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, rebind to get the proper allocator: */
typedef typename CML_DEFAULT_ARRAY_ALLOC
::rebind<promoted_scalar>::other allocator;
/* Finally, generate the promoted array type: */
typedef dynamic_1D<promoted_scalar,allocator> type;
};
/* Promote fixed 2D+1D array expressions to a fixed 1D array: */
template<class A1, class A2>
struct promote<A1,A2,twod_tag,oned_tag,fixed_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, deduce the array size: */
enum { Size = (size_t)A1::array_rows };
/* Finally, generate the promoted array type: */
typedef fixed_1D<promoted_scalar,Size> type;
};
/* Promote fixed 1D+2D array expressions to a fixed 1D array: */
template<class A1, class A2>
struct promote<A1,A2,oned_tag,twod_tag,fixed_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, deduce the array size: */
enum { Size = (size_t)A2::array_cols };
/* Finally, generate the promoted array type: */
typedef fixed_1D<promoted_scalar,Size> type;
};
/* Promote dynamic 2D+1D array expression to a 1D dynamic array: */
template<class A1, class A2>
struct promote<A1,A2,twod_tag,oned_tag,dynamic_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, rebind to get the proper allocator: */
typedef typename CML_DEFAULT_ARRAY_ALLOC
::rebind<promoted_scalar>::other allocator;
/* Finally, generate the promoted array type: */
typedef dynamic_1D<promoted_scalar,allocator> type;
};
/* Promote dynamic 1D+2D array expression to a 1D dynamic array: */
template<class A1, class A2>
struct promote<A1,A2,oned_tag,twod_tag,dynamic_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, rebind to get the proper allocator: */
typedef typename CML_DEFAULT_ARRAY_ALLOC
::rebind<promoted_scalar>::other allocator;
/* Finally, generate the promoted array type: */
typedef dynamic_1D<promoted_scalar,allocator> type;
};
/* This is a helper to deduce the result of a promoted 2D array: */
template<typename LeftL, typename RightL> struct deduce_layout {
#if defined(CML_ALWAYS_PROMOTE_TO_DEFAULT_LAYOUT)
typedef CML_DEFAULT_ARRAY_LAYOUT promoted_layout;
#else
typedef typename select_if<
same_type<LeftL,RightL>::is_true, LeftL,
CML_DEFAULT_ARRAY_LAYOUT>::result promoted_layout;
#endif
};
/* Promote 2D fixed-size arrays to a 2D fixed-size array. The resulting
* matrix has the same number of rows as A1, and the same number of
* columns as A2.
*/
template<class A1, class A2>
struct promote<A1,A2,twod_tag,twod_tag,fixed_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, deduce the array size: */
enum {
Rows = (size_t)A1::array_rows,
Cols = (size_t)A2::array_cols
};
/* Then deduce the array layout: */
typedef typename A1::layout left_layout;
typedef typename A2::layout right_layout;
typedef typename deduce_layout<left_layout,right_layout>
::promoted_layout promoted_layout;
/* Finally, generate the promoted array type: */
typedef fixed_2D<promoted_scalar,Rows,Cols,promoted_layout> type;
};
/* Promote 2D dynamic arrays to a 2D dynamic array: */
template<class A1, class A2>
struct promote<A1,A2,twod_tag,twod_tag,dynamic_size_tag>
{
typedef typename A1::value_type left_scalar;
typedef typename A2::value_type right_scalar;
/* First, promote the scalar type: */
typedef typename ScalarPromote<
left_scalar,right_scalar>::type promoted_scalar;
/* Next, rebind to get the proper allocator: */
typedef typename CML_DEFAULT_ARRAY_ALLOC
::rebind<promoted_scalar>::other allocator;
/* Then deduce the array layout: */
typedef typename A1::layout left_layout;
typedef typename A2::layout right_layout;
typedef typename deduce_layout<left_layout,right_layout>
::promoted_layout promoted_layout;
/* Finally, generate the promoted array type: */
typedef dynamic_2D<promoted_scalar,promoted_layout,allocator> type;
};
} // namespace detail
/** Class to promote array types.
*
* Both arguments must be array types.
*
* @sa fixed_1D
* @sa fixed_2D
* @sa dynamic_1D
* @sa dynamic_2D
*/
template<class A1, class A2>
struct ArrayPromote
{
/* Shorthand: */
//typedef typename A1::value_type left_scalar;
//typedef typename A2::value_type right_scalar;
typedef typename A1::dimension_tag left_dtag;
typedef typename A2::dimension_tag right_dtag;
/* Deduce the proper type based upon the characteristics of AT1 and
* AT2. This is the table of type conversions:
*
* AT1 AT2 Result
* memory size memory size memory size
*
* fixed fixed fixed fixed fixed fixed
* fixed fixed dynamic dynamic dynamic dynamic
* fixed fixed external fixed fixed fixed
* fixed fixed external dynamic dynamic dynamic
*
* dynamic dynamic fixed fixed dynamic dynamic
* dynamic dynamic dynamic dynamic dynamic dynamic
* dynamic dynamic external fixed dynamic dynamic
* dynamic dynamic external dynamic dynamic dynamic
*
* external fixed external fixed fixed fixed
* external fixed fixed fixed fixed fixed
* external fixed dynamic dynamic dynamic dynamic
* external fixed external dynamic dynamic dynamic
*
* external dynamic external fixed dynamic dynamic
* external dynamic fixed fixed dynamic dynamic
* external dynamic dynamic dynamic dynamic dynamic
* external dynamic external dynamic dynamic dynamic
*
* Note that if one argument is a dynamically-sized array, the result
* must be a dynamically allocated and sized array. Likewise, if both
* arguments have fixed size, the result can be a fixed-sized array.
*/
/* Check if both arguments are fixed-size arrays. If so, the promoted
* array will be a fixed array, and if not, it will be a dynamic array:
*/
typedef typename select_if<
(same_type<typename A1::size_tag, fixed_size_tag>::is_true
&& same_type<typename A2::size_tag, fixed_size_tag>::is_true),
fixed_size_tag, /* True */
dynamic_size_tag /* False */
>::result promoted_size_tag;
/* Deduce the promoted type: */
typedef typename detail::promote<
A1, A2, left_dtag, right_dtag, promoted_size_tag>::type type;
};
/* Cleanup internal macros: */
#undef VAL_MAX
} // namespace et
} // namespace cml
#endif
// -------------------------------------------------------------------------
// vim:ft=cpp