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SIMD sqrt optimizations including lowp

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This commit is contained in:
Christophe Riccio
2016-05-29 02:57:53 +02:00
parent 449c7ccedf
commit 20cf68679c
6 changed files with 68 additions and 55 deletions
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26
glm/simd/common.h
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@@ -178,30 +178,4 @@ GLM_FUNC_QUALIFIER __m128 glm_f32v4_inf(__m128 x)
return _mm_castsi128_ps(_mm_cmpeq_epi32(t2, _mm_set1_epi32(0xFF000000))); // exponent is all 1s, fraction is 0
}
// SSE scalar reciprocal sqrt using rsqrt op, plus one Newton-Rhaphson iteration
// By Elan Ruskin, http://assemblyrequired.crashworks.org/
GLM_FUNC_QUALIFIER __m128 glm_f32v1_sqrt_wip(__m128 x)
{
__m128 const Rcp0 = _mm_rsqrt_ss(x); // "estimate" opcode
__m128 const Mul0 = _mm_mul_ss(_mm_set1_ps(0.5f), Rcp0);
__m128 const Mul1 = _mm_mul_ss(Rcp0, Rcp0);
__m128 const Mul2 = _mm_mul_ss(x, Mul1);
__m128 const Sub0 = _mm_sub_ss(_mm_set1_ps(3.0f), Mul2);
__m128 const Mul3 = _mm_mul_ss(Mul0, Sub0);
return Mul3;
}
// SSE scalar reciprocal sqrt using rsqrt op, plus one Newton-Rhaphson iteration
// By Elan Ruskin, http://assemblyrequired.crashworks.org/
GLM_FUNC_QUALIFIER __m128 glm_f32v4_sqrt_wip(__m128 x)
{
__m128 const Rcp0 = _mm_rsqrt_ps(x); // "estimate" opcode
__m128 const Mul0 = _mm_mul_ps(_mm_set1_ps(0.5f), Rcp0);
__m128 const Mul1 = _mm_mul_ps(Mul0, Mul0);
__m128 const Mul2 = _mm_mul_ps(x, Mul1);
__m128 const Sub0 = _mm_sub_ps(_mm_set1_ps(3.0f), Mul2);
__m128 const Mul3 = _mm_mul_ps(Mul0, Sub0);
return Mul3;
}
#endif//GLM_ARCH & GLM_ARCH_SSE2_BIT

17
glm/simd/exponential.h
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@@ -3,3 +3,20 @@
#pragma once
#if GLM_ARCH & GLM_ARCH_SSE2_BIT
// SSE scalar reciprocal sqrt using rsqrt op, plus one Newton-Rhaphson iteration
// By Elan Ruskin, http://assemblyrequired.crashworks.org/
GLM_FUNC_QUALIFIER __m128 glm_f32v1_sqrt_lowp(__m128 x)
{
return _mm_mul_ss(_mm_rsqrt_ss(x), x);
}
// SSE scalar reciprocal sqrt using rsqrt op, plus one Newton-Rhaphson iteration
// By Elan Ruskin, http://assemblyrequired.crashworks.org/
GLM_FUNC_QUALIFIER __m128 glm_f32v4_sqrt_lowp(__m128 x)
{
return _mm_mul_ps(_mm_rsqrt_ps(x), x);
}
#endif//GLM_ARCH & GLM_ARCH_SSE2_BIT