#ifndef scalar_promotions_h
#define scalar_promotions_h
+#include <complex>
#include <cml/core/cml_meta.h>
namespace cml {
namespace et {
+// #define CML_USE_OLD_SCALAR_PROMOTIONS
+#if !defined(CML_USE_OLD_SCALAR_PROMOTIONS)
+
+/* The type promotion code below is a slightly modified version of:
+ * http://ubiety.uwaterloo.ca/~tveldhui/papers/techniques/techniques01.html
+ */
+namespace detail {
+
+template<class T>
+struct precision_trait {
+ enum { precisionRank = 0,
+ knowPrecisionRank = 0 };
+};
+
+#define DECLARE_PRECISION(T,rank) \
+ template<> \
+ struct precision_trait< T > { \
+ enum { precisionRank = rank, \
+ knowPrecisionRank = 1 }; \
+ };
+
+DECLARE_PRECISION(int,100)
+DECLARE_PRECISION(unsigned int,200)
+DECLARE_PRECISION(long,300)
+DECLARE_PRECISION(unsigned long,400)
+
+DECLARE_PRECISION(long long,425)
+DECLARE_PRECISION(unsigned long long,475)
+
+DECLARE_PRECISION(float,500)
+DECLARE_PRECISION(double,600)
+DECLARE_PRECISION(long double,700)
+DECLARE_PRECISION(std::complex<float>,800)
+DECLARE_PRECISION(std::complex<double>,900)
+DECLARE_PRECISION(std::complex<long double>,1000)
+
+template<class T>
+struct autopromote_trait {
+ typedef T T_numtype;
+};
+
+#define DECLARE_AUTOPROMOTE(T1,T2) \
+ template<> \
+ struct autopromote_trait<T1> { \
+ typedef T2 T_numtype; \
+ };
+
+// These are the odd cases where small integer types
+// are automatically promoted to int or unsigned int for
+// arithmetic.
+DECLARE_AUTOPROMOTE(bool, int)
+DECLARE_AUTOPROMOTE(char, int)
+DECLARE_AUTOPROMOTE(unsigned char, int)
+DECLARE_AUTOPROMOTE(short int, int)
+DECLARE_AUTOPROMOTE(short unsigned int, unsigned int)
+
+template<class T1, class T2, int promoteToT1>
+struct promote2 {
+ typedef T1 T_promote;
+};
+
+template<class T1, class T2>
+struct promote2<T1,T2,0> {
+ typedef T2 T_promote;
+};
+
+template<class T1_orig, class T2_orig>
+struct promote_trait {
+ // Handle promotion of small integers to int/unsigned int
+ typedef typename autopromote_trait<T1_orig>::T_numtype T1;
+ typedef typename autopromote_trait<T2_orig>::T_numtype T2;
+
+ // True if T1 is higher ranked
+ enum {
+ T1IsBetter =
+ (int) precision_trait<T1>::precisionRank >
+ (int) precision_trait<T2>::precisionRank,
+
+ // True if we know ranks for both T1 and T2
+ knowBothRanks =
+ precision_trait<T1>::knowPrecisionRank
+ && precision_trait<T2>::knowPrecisionRank,
+
+ // True if we know T1 but not T2
+ knowT1butNotT2 = precision_trait<T1>::knowPrecisionRank
+ && !(precision_trait<T2>::knowPrecisionRank),
+
+ // True if we know T2 but not T1
+ knowT2butNotT1 = precision_trait<T2>::knowPrecisionRank
+ && !(precision_trait<T1>::knowPrecisionRank),
+
+ // True if T1 is bigger than T2
+ T1IsLarger = sizeof(T1) >= sizeof(T2),
+
+ // We know T1 but not T2: true
+ // We know T2 but not T1: false
+ // Otherwise, if T1 is bigger than T2: true
+ defaultPromotion = knowT1butNotT2 ? false :
+ (knowT2butNotT1 ? true : T1IsLarger)
+ };
+
+ // If we have both ranks, then use them.
+ // If we have only one rank, then use the unknown type.
+ // If we have neither rank, then promote to the larger type.
+
+ enum {
+ promoteToT1 = (knowBothRanks ? T1IsBetter : defaultPromotion)
+ ? 1 : 0
+ };
+
+ typedef typename promote2<T1,T2,promoteToT1>::T_promote T_promote;
+};
+
+} // namespace detail
+
+/** Defers to detail::promote_trait<>. */
+template<class E1, class E2> struct ScalarPromote
+{
+ typedef typename detail::promote_trait<E1,E2>::T_promote type;
+};
+
+#else
+
namespace detail {
/** @class IntPromote
*/
template<class E1_in, class E2_in> struct ScalarPromote
{
-
/* Integral-promote the types (if possible). */
typedef typename detail::IntPromote<E1_in>::result E1;
typedef typename detail::IntPromote<E2_in>::result E2;
same_type<float_filter,void>::is_true,
int_filter, float_filter>::result type;
};
+#endif
} // namespace et
} // namespace cml