new interface for remove_trailing_zeros(uint32_t& n, int s = 0)

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Florimond Collette 2023-05-18 11:20:56 +02:00 committed by GitHub
parent 8f51cc693b
commit d9943cd4b2
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@ -1128,7 +1128,7 @@ bool is_left_endpoint_integer_shorter_interval(int exponent) noexcept {
}
// Remove trailing zeros from n and return the number of zeros removed (float)
FMT_INLINE int remove_trailing_zeros(uint32_t& n) noexcept {
FMT_INLINE int remove_trailing_zeros(uint32_t& n, int s = 0) noexcept {
FMT_ASSERT(n != 0, "");
// Modular inverse of 5 (mod 2^32): (mod_inv_5 * 5) mod 2^32 = 1.
// See https://github.com/fmtlib/fmt/issues/3163 for more details.
@ -1137,7 +1137,6 @@ FMT_INLINE int remove_trailing_zeros(uint32_t& n) noexcept {
const uint32_t mod_inv_25 =
static_cast<uint32_t>(uint64_t(mod_inv_5) * mod_inv_5);
int s = 0;
while (true) {
auto q = rotr(n * mod_inv_25, 2);
if (q > max_value<uint32_t>() / 100) break;
@ -1165,7 +1164,7 @@ FMT_INLINE int remove_trailing_zeros(uint64_t& n) noexcept {
// If yes, work with the quotient...
auto n32 = static_cast<uint32_t>(nm.high() >> (90 - 64));
// ... and use the 32 bit variant of the function
auto s = remove_trailing_zeros(n32);
int s = remove_trailing_zeros(n32, 8);
n = n32;
return s;
}