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added {rsqrt,rcp}d support for sse4.h

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Evghenii
2014-02-05 13:42:45 +01:00
parent 688d9c9a82
commit f225b558ec
1 changed files with 31 additions and 0 deletions
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31
examples/intrinsics/sse4.h
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@@ -2420,6 +2420,21 @@ static FORCEINLINE __vec4_f __rcp_varying_float(__vec4_f v) {
return r;
}
static FORCEINLINE __vec4_d __rcp_varying_double(__vec4_d x) {
__vec4_i64 ex = __and(__cast_bits(__vec4_i64(), x), __smear_i64<__vec4_i64>(0x7fe0000000000000));
__vec4_d exp = __cast_bits(__vec4_d(), __sub(__smear_i64<__vec4_i64>(0x7fd0000000000000), ex));
__vec4_f xf = __cast_fptrunc(__vec4_f(), __mul(x, exp));
__vec4_f yf = __rcp_varying_float(xf);
__vec4_d y = __mul(__cast_fpext(__vec4_d(), yf), exp);
y = __add(y, __mul(y, __sub(__smear_double<__vec4_d>(2.0), __mul(x, y))));
y = __add(y, __mul(y, __sub(__smear_double<__vec4_d>(2.0), __mul(x, y))));
return y;
}
static FORCEINLINE double __rcp_uniform_double(double v)
{
return __extract_element(__rcp_varying_double(__smear_double<__vec4_d>(v)),0);
}
static FORCEINLINE __vec4_f __rsqrt_varying_float(__vec4_f v) {
__m128 rsqrt = _mm_rsqrt_ps(v.v);
// Newton-Raphson iteration to improve precision
@@ -2431,6 +2446,22 @@ static FORCEINLINE __vec4_f __rsqrt_varying_float(__vec4_f v) {
__m128 half_scale = _mm_mul_ps(_mm_set1_ps(0.5), rs_mul);
return half_scale;
}
static FORCEINLINE __vec4_d __rsqrt_varying_double(__vec4_d x) {
__vec4_i64 ex = __and(__cast_bits(__vec4_i64(), x), __smear_i64<__vec4_i64>(0x7fe0000000000000));
__vec4_d exp = __cast_bits(__vec4_d(), __sub(__smear_i64<__vec4_i64>(0x7fd0000000000000), ex));
__vec4_d exph = __cast_bits(__vec4_d(), __sub(__smear_i64<__vec4_i64>(0x5fe0000000000000), __lshr(ex,1)));
__vec4_f xf = __cast_fptrunc(__vec4_f(), __mul(x, exp));
__vec4_f yf = __rsqrt_varying_float(xf);
__vec4_d y = __mul(__cast_fpext(__vec4_d(), yf), exph);
__vec4_d xh = __mul(x, __smear_double<__vec4_d>(0.5));
y = __add(y, __mul(y, __sub(__smear_double<__vec4_d>(0.5), __mul(xh, __mul(y,y)))));
y = __add(y, __mul(y, __sub(__smear_double<__vec4_d>(0.5), __mul(xh, __mul(y,y)))));
return y;
}
static FORCEINLINE double __rsqrt_uniform_double(double v)
{
return __extract_element(__rsqrt_varying_double(__smear_double<__vec4_d>(v)),0);
}
static FORCEINLINE __vec4_f __sqrt_varying_float(__vec4_f v) {
return _mm_sqrt_ps(v.v);