sse

I want to convert an array of unsigned short numbers to float using SSE. Let's say __m128i xVal; // Has 8 16-bit unsigned integers __m128 y1, y2; // 2 xmm registers for 8 float values I want first 4 uint16 in y1 & next 4 uint16 in y2. Need to know which sse intrinsic to use. You need to first unpack your vector of 8 x 16 bit unsigned shorts into two vectors of 32 bit unsigned ints, then convert each of these vectors to float: __m128i xlo = _mm_unpacklo_epi16(x, _mm_set1_epi16(0)); __m128i xhi = _mm_unpackhi_epi16(x, _mm_set1_epi16(0)); __m128 ylo = _mm_cvtepi32_ps(xlo); __m128 yhi = _mm

I am looking for SIMD math libraries (preferably open source) for SSE and AVX. I mean for example if I have a AVX register v with 8 float values I want sin(v) to return the sin of all eight values at once. AMD has a propreitery library, LibM http://developer.amd.com/tools/cpu-development/libm/ which has some SIMD math functions but LibM only uses AVX if it detects FMA4 which Intel CPUs don't have. Also I'm not sure it fully uses AVX as all the function names end in s4 (d2) and not s8 (d4). It give better performance than the standard math libraries on Intel CPUs but it's not much better. Intel

This question already has an answer here: Sum reduction of unsigned bytes without overflow, using SSE2 on Intel 2 answers I am new to SSE2 instructions. I have found an instruction _mm_add_epi8 which can add two array elements. But I want an SSE instruction which can add all elements of an array. I was trying to develop this concept using this code: #include <iostream> #include <conio.h> #include <emmintrin.h> void sse(unsigned char* a,unsigned char* b); void main() { /*unsigned char *arr; arr=(unsigned char *)malloc(50);*/ unsigned char arr[]={'a','b','c','d','e','f','i','j','k','l','m','n',

Quick Summary: I have an array of 24-bit values. Any suggestion on how to quickly expand the individual 24-bit array elements into 32-bit elements? Details: I'm processing incoming video frames in realtime using Pixel Shaders in DirectX 10. A stumbling block is that my frames are coming in from the capture hardware with 24-bit pixels (either as YUV or RGB images), but DX10 takes 32-bit pixel textures. So, I have to expand the 24-bit values to 32-bits before I can load them into the GPU. I really don't care what I set the remaining 8 bits to, or where the incoming 24-bits are in that 32-bit

I should count the number of set bits of a __m128i register. In particular, I should write two functions that are able to count the number of bits of the register, using the following ways. The total number of set bits of the register. The number of set bits for each byte of the register. Are there intrinsic functions that can perform, wholly or partially, the above operations? Here are some codes I used in an old project ( there is a research paper about it ). The function popcnt8 below computes the number of bits set in each byte. SSE2-only version (based on Algorithm 3 in Hacker's Delight