diff options
| author | Francisco Jerez <currojerez@riseup.net> | 2015-07-27 18:42:31 +0300 |
|---|---|---|
| committer | Francisco Jerez <currojerez@riseup.net> | 2015-07-29 19:30:11 +0300 |
| commit | 4529916dfd227af6c4e151f45261db22157fe45f (patch) | |
| tree | 59826f327c1db978a8a0a946b81915e24987b212 | |
| parent | eaba922582cfdccc7b198f9b23d8bd3c26197d03 (diff) | |
i965/fs: Don't set exec_all on instructions wider than the original in lower_simd_width.
This could have led to somewhat increased bandwidth usage for lowered
texturing instructions on Gen4 (which is the only case in which
lower_width may be greater than inst->exec_size). After the previous
patches the invariant mentioned in the comment should no longer be
assumed by any of the other optimization and lowering passes, so the
exec_all() call shouldn't be necessary anymore.
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.com>
| -rw-r--r-- | src/mesa/drivers/dri/i965/brw_fs.cpp | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp index 57e4dd783e..4947f24dc4 100644 --- a/src/mesa/drivers/dri/i965/brw_fs.cpp +++ b/src/mesa/drivers/dri/i965/brw_fs.cpp @@ -4163,10 +4163,15 @@ fs_visitor::lower_simd_width() const unsigned lower_width = get_lowered_simd_width(devinfo, inst); if (lower_width != inst->exec_size) { - /* Builder matching the original instruction. */ + /* Builder matching the original instruction. We may also need to + * emit an instruction of width larger than the original, set the + * execution size of the builder to the highest of both for now so + * we're sure that both cases can be handled. + */ const fs_builder ibld = bld.at(block, inst) .exec_all(inst->force_writemask_all) - .group(inst->exec_size, inst->force_sechalf); + .group(MAX2(inst->exec_size, lower_width), + inst->force_sechalf); /* Split the copies in chunks of the execution width of either the * original or the lowered instruction, whichever is lower. @@ -4189,14 +4194,11 @@ fs_visitor::lower_simd_width() split_inst.exec_size = lower_width; split_inst.eot = inst->eot && i == n - 1; - /* Set exec_all if the lowered width is higher than the original - * to avoid breaking the compiler invariant that no control - * flow-masked instruction is wider than the shader's - * dispatch_width. Then transform the sources and destination and - * emit the lowered instruction. + /* Select the correct channel enables for the i-th group, then + * transform the sources and destination and emit the lowered + * instruction. */ - const fs_builder lbld = ibld.exec_all(lower_width > inst->exec_size) - .group(lower_width, i); + const fs_builder lbld = ibld.group(lower_width, i); for (unsigned j = 0; j < inst->sources; j++) { if (inst->src[j].file != BAD_FILE && |