From 2eaed464e2080d8321d3903b71086a1ecfc4ee4a Mon Sep 17 00:00:00 2001 From: Szabolcs Nagy Date: Wed, 4 Sep 2013 15:52:54 +0000 Subject: [PATCH] math: use float_t and double_t in scalbnf and scalbn remove STRICT_ASSIGN (c99 semantics is assumed) and use the conventional union to prepare the scaling factor (so libm.h is no longer needed) --- src/math/scalbn.c | 18 ++++++++++-------- src/math/scalbnf.c | 18 ++++++++++-------- 2 files changed, 20 insertions(+), 16 deletions(-) diff --git a/src/math/scalbn.c b/src/math/scalbn.c index 1fec432f..530e07c7 100644 --- a/src/math/scalbn.c +++ b/src/math/scalbn.c @@ -1,29 +1,31 @@ -#include "libm.h" +#include +#include double scalbn(double x, int n) { - double scale; + union {double f; uint64_t i;} u; + double_t y = x; if (n > 1023) { - x *= 0x1p1023; + y *= 0x1p1023; n -= 1023; if (n > 1023) { - x *= 0x1p1023; + y *= 0x1p1023; n -= 1023; if (n > 1023) n = 1023; } } else if (n < -1022) { - x *= 0x1p-1022; + y *= 0x1p-1022; n += 1022; if (n < -1022) { - x *= 0x1p-1022; + y *= 0x1p-1022; n += 1022; if (n < -1022) n = -1022; } } - INSERT_WORDS(scale, (uint32_t)(0x3ff+n)<<20, 0); - STRICT_ASSIGN(double, x, x * scale); + u.i = (uint64_t)(0x3ff+n)<<52; + x = y * u.f; return x; } diff --git a/src/math/scalbnf.c b/src/math/scalbnf.c index c0eeaf84..0b62c3c7 100644 --- a/src/math/scalbnf.c +++ b/src/math/scalbnf.c @@ -1,29 +1,31 @@ -#include "libm.h" +#include +#include float scalbnf(float x, int n) { - float scale; + union {float f; uint32_t i;} u; + float_t y = x; if (n > 127) { - x *= 0x1p127f; + y *= 0x1p127f; n -= 127; if (n > 127) { - x *= 0x1p127f; + y *= 0x1p127f; n -= 127; if (n > 127) n = 127; } } else if (n < -126) { - x *= 0x1p-126f; + y *= 0x1p-126f; n += 126; if (n < -126) { - x *= 0x1p-126f; + y *= 0x1p-126f; n += 126; if (n < -126) n = -126; } } - SET_FLOAT_WORD(scale, (uint32_t)(0x7f+n)<<23); - STRICT_ASSIGN(float, x, x * scale); + u.i = (uint32_t)(0x7f+n)<<23; + x = y * u.f; return x; } -- 2.25.1