Use int16 min/max for _mm_set_epi16() calls #395
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This fixes a bug that causes g0 overflows when compiled on Intel processors and run on AMD Ryzen processors. According to Intel, the `_mm_set_epi16()` function takes signed shorts (int16): https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=mm_set_epi16&ig_expand=6355,6355 But 0-65535 is the range of uint16, not int16; causing an overflow to -1. This is warned of by the compiler: `implict conversion from int to short changes value from 65535 to -1` For whatever reason, compiling and running on AMD Ryzen chip succeeded fine. Compiling and runing on an Intel chip also worked fine. But compiling on Intel and running on AMD caused an exception. Using the int16 range fixes the problem. However, this is not my skill set and I am not sure if this is the right fix. Please verify. Thank you!
mholt
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Feb 28, 2023
Hopefully. Still need to test and verify it. See upstream PR: strukturag/libde265#395
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This fixes a bug that causes g0 overflows when compiled on Intel processors and run on AMD Ryzen processors.
According to Intel, the
_mm_set_epi16()function takes signed shorts (int16): https://www.intel.com/content/www/us/en/docs/intrinsics-guide/index.html#text=mm_set_epi16&ig_expand=6355,6355But 0-65535 is the range of uint16, not int16; causing an overflow to -1. This is warned of by the compiler:
implict conversion from int to short changes value from 65535 to -1For whatever reason, compiling and running on AMD Ryzen chip succeeded fine. Compiling and runing on an Intel chip also worked fine. But compiling on Intel and running on AMD caused an exception.
Using the int16 range fixes the problem. However, this is not my skill set and I am not sure if this is the right fix. Please verify. Thank you!