Status: New
Owner: ----
New issue 2228 by [email protected]: Generate SIMD instructions for
SIMD-like code patterns
http://code.google.com/p/v8/issues/detail?id=2228
Turning typed arrays code like
function add_ps(a, b) {
a[0] += b[0];
a[1] += b[1];
a[2] += b[2];
a[3] += b[3];
}
function mul_ps(a, b) {
a[0] *= b[0];
a[1] *= b[1];
a[2] *= b[2];
a[3] *= b[3];
}
var vectors = new Float32Array(400000);
var adds = new Float32Array(4000);
for (var i=0; i<vectors.length; i+=4) {
var a = new Float32Array(vectors.buffer, i*4, 4);
for (var j=0; j<adds.length; j+=4) {
var b = new Float32Array(adds.buffer, j*4, 4);
add_ps(a, b);
mul_ps(a, b);
}
}
into something like the following C snippet
float *vectors;
float *adds;
// ... initialize vectors and adds
__m128 a, b;
for (int i=0; i<vectors_length; i+=4) {
a = _mm_load_ps(vectors+i);
for (int j=0; j<adds_length; j+=4) {
b = _mm_load_ps(adds+j);
a = _mm_add_ps(a, b);
a = _mm_mul_ps(a, b);
}
_mm_store_ps(vectors+i, a);
}
would be nice.
--
v8-dev mailing list
[email protected]
http://groups.google.com/group/v8-dev
