diff options
| author | Matt Turner <[email protected]> | 2013-09-17 18:02:05 -0700 |
|---|---|---|
| committer | Matt Turner <[email protected]> | 2013-10-07 10:41:16 -0700 |
| commit | 6f9428eb68bb0f7592f4384455fc7aab23940d92 (patch) | |
| tree | 4c84da7111570d6bd02b07122bda7414d8273d36 /src/glsl/lower_discard.cpp | |
| parent | 6c125973f31addf903921647e8244abccb944e1a (diff) | |
glsl: Implement usubBorrow() built-in for ARB_gpu_shader5.
i965 implements this with a single (multiple destination) instruction,
SUBB. Emitting SUBB directly from usubBorrow() would be ideal, but our
optimization passes don't know how to copy with expressions with
side-effects.
Radeon has an SUBB_UINT instruction that only generates the borrow
bit. I've chosen to go this route and implement usubBorrow() by doing the
subtraction and the borrow operations separately.
Reviewed-by: Kenneth Graunke <[email protected]>
Reviewed-by: Ian Romanick <[email protected]>
Diffstat (limited to 'src/glsl/lower_discard.cpp')
0 files changed, 0 insertions, 0 deletions