diff options
| author | Tom Stellard <tstellar@gmail.com> | 2011-04-16 12:39:09 -0700 |
|---|---|---|
| committer | Tom Stellard <tstellar@gmail.com> | 2011-04-16 14:23:04 -0700 |
| commit | ea95bf7d8954d1d98113931c83ca130ba02e0330 (patch) | |
| tree | 59f719f5e83f111b25fd9f14350f3b5a712d64f5 | |
| parent | b8050add5669ccc91ff658222ce97682886f2a2f (diff) | |
r300/compiler: Fix incorrect presubtract conversion
ADD instructions with constant swizzles can't be converted to
presubtract operations.
(cherry picked from commit 0fa81d6d05b12db825be31533d9a485625ae35e2)
| -rw-r--r-- | src/mesa/drivers/dri/r300/compiler/radeon_optimize.c | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c b/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c index bebe8061832..b174d7178e4 100644 --- a/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c +++ b/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c @@ -647,10 +647,34 @@ static int is_presub_candidate( { const struct rc_opcode_info * info = rc_get_opcode_info(inst->U.I.Opcode); unsigned int i; + unsigned int is_constant[2] = {0, 0}; + + assert(inst->U.I.Opcode == RC_OPCODE_ADD); if (inst->U.I.PreSub.Opcode != RC_PRESUB_NONE || inst->U.I.SaturateMode) return 0; + /* If both sources use a constant swizzle, then we can't convert it to + * a presubtract operation. In fact for the ADD and SUB presubtract + * operations neither source can contain a constant swizzle. This + * specific case is checked in peephole_add_presub_add() when + * we make sure the swizzles for both sources are equal, so we + * don't need to worry about it here. */ + for (i = 0; i < 2; i++) { + int chan; + for (chan = 0; chan < 4; chan++) { + rc_swizzle swz = + get_swz(inst->U.I.SrcReg[i].Swizzle, chan); + if (swz == RC_SWIZZLE_ONE + || swz == RC_SWIZZLE_ZERO + || swz == RC_SWIZZLE_HALF) { + is_constant[i] = 1; + } + } + } + if (is_constant[0] && is_constant[1]) + return 0; + for(i = 0; i < info->NumSrcRegs; i++) { struct rc_src_register src = inst->U.I.SrcReg[i]; if (src_reads_dst_mask(src, inst->U.I.DstReg)) |