Augment NumTraits with min/max_exponent().

Replace usage of `std::numeric_limits<...>::min/max_exponent` in
codebase.  Also replaced some other `numeric_limits` usages in
affected tests with the `NumTraits` equivalent.

Fixes #2148
This commit is contained in:
Antonio Sanchez
2021-02-12 13:14:05 -08:00
committed by Rasmus Munk Larsen
parent 9fb7062440
commit 75ce9cd2a7
6 changed files with 74 additions and 54 deletions

View File

@@ -36,7 +36,7 @@ template<typename Packet> EIGEN_STRONG_INLINE EIGEN_DEVICE_FUNC
Packet pfrexp_generic_get_biased_exponent(const Packet& a) {
typedef typename unpacket_traits<Packet>::type Scalar;
typedef typename unpacket_traits<Packet>::integer_packet PacketI;
enum { mantissa_bits = numext::numeric_limits<Scalar>::digits - 1};
enum { mantissa_bits = NumTraits<Scalar>::digits() - 1};
return pcast<PacketI, Packet>(plogical_shift_right<mantissa_bits>(preinterpret<PacketI>(pabs(a))));
}
@@ -48,7 +48,7 @@ Packet pfrexp_generic(const Packet& a, Packet& exponent) {
typedef typename make_unsigned<typename make_integer<Scalar>::type>::type ScalarUI;
enum {
TotalBits = sizeof(Scalar) * CHAR_BIT,
MantissaBits = numext::numeric_limits<Scalar>::digits - 1,
MantissaBits = NumTraits<Scalar>::digits() - 1,
ExponentBits = int(TotalBits) - int(MantissaBits) - 1
};
@@ -116,7 +116,7 @@ Packet pldexp_generic(const Packet& a, const Packet& exponent) {
typedef typename unpacket_traits<PacketI>::type ScalarI;
enum {
TotalBits = sizeof(Scalar) * CHAR_BIT,
MantissaBits = numext::numeric_limits<Scalar>::digits - 1,
MantissaBits = NumTraits<Scalar>::digits() - 1,
ExponentBits = int(TotalBits) - int(MantissaBits) - 1
};
@@ -135,7 +135,7 @@ Packet pldexp_generic(const Packet& a, const Packet& exponent) {
// Explicitly multiplies
// a * (2^e)
// clamping e to the range
// [numeric_limits<Scalar>::min_exponent-2, numeric_limits<Scalar>::max_exponent]
// [NumTraits<Scalar>::min_exponent()-2, NumTraits<Scalar>::max_exponent()]
//
// This is approx 7x faster than pldexp_impl, but will prematurely over/underflow
// if 2^e doesn't fit into a normal floating-point Scalar.
@@ -148,7 +148,7 @@ struct pldexp_fast_impl {
typedef typename unpacket_traits<PacketI>::type ScalarI;
enum {
TotalBits = sizeof(Scalar) * CHAR_BIT,
MantissaBits = numext::numeric_limits<Scalar>::digits - 1,
MantissaBits = NumTraits<Scalar>::digits() - 1,
ExponentBits = int(TotalBits) - int(MantissaBits) - 1
};
@@ -1480,8 +1480,8 @@ Packet generic_pow(const Packet& x, const Packet& y) {
const Packet y_is_nan = pandnot(ptrue(y), pcmp_eq(y, y));
const Packet abs_y_is_inf = pcmp_eq(pabs(y), cst_pos_inf);
EIGEN_CONSTEXPR Scalar huge_exponent =
(std::numeric_limits<Scalar>::max_exponent * Scalar(EIGEN_LN2)) /
std::numeric_limits<Scalar>::epsilon();
(NumTraits<Scalar>::max_exponent() * Scalar(EIGEN_LN2)) /
NumTraits<Scalar>::epsilon();
const Packet abs_y_is_huge = pcmp_le(pset1<Packet>(huge_exponent), pabs(y));
// Predicates for whether y is integer and/or even.