xemu-project/nv2a_vsh_cpu
1
0
Fork 0
mirror of https://github.com/xemu-project/nv2a_vsh_cpu.git synced 2024-11-26 19:20:22 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

Fixes LOG.

Browse Source
This commit is contained in:
Erik Abair 2022-06-23 20:13:24 -07:00
parent 2de2148592
commit 5aa83ec399
2 changed files with 12 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
src/nv2a_vsh_cpu.c
View File

@ -246,10 +246,15 @@ void nv2a_vsh_cpu_log(float *out, const float *inputs) {
out[1] = 1.0f;
out[2] = INFINITY;
} else {
int exp = 0;
out[1] = frexpf(tmp, &exp);
out[0] = (float)exp;
out[2] = out[0] + log2f(tmp);
// frexpf returns values that do not match nv2a, so the exponent is
// extracted manually.
uint32_t tmp_int = *(uint32_t*)&tmp;
uint32_t exponent = ((tmp_int >> 23) & 0xFF) - 127;
uint32_t mantissa = (tmp_int & 0x7FFFFF) | 0x3F800000;
out[0] = (float)exponent;
out[1] = *(float*)&mantissa;
out[2] = log2f(tmp);
}
out[3] = 1.0f;

3
test/operations/test_basic.cpp
View File

@ -92,7 +92,10 @@ BOOST_AUTO_TEST_CASE(add_trivial) {
// }
//}
// Returned values are very close to correct and could be checked with a more
// permissive float equality.
//BOOST_AUTO_TEST_CASE(log_trivial) {
// // 0xDB5056B0
// float inputs[][4] = {
// {-5.864211e16f, 0.0f, 0.0f, 0.0f},
// {0.0f, 0.0f, 0.0f, 0.0f},