diff options
| -rw-r--r-- | src/mesa/drivers/dri/r300/compiler/radeon_optimize.c | 45 |
1 files changed, 31 insertions, 14 deletions
diff --git a/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c b/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c index c15a9b1c45..e2889302e6 100644 --- a/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c +++ b/src/mesa/drivers/dri/r300/compiler/radeon_optimize.c @@ -475,8 +475,8 @@ static void constant_folding(struct radeon_compiler * c, struct rc_instruction * } /** - * This function returns a writemask that indicates wich components are - * read by src and also written by dst. + * If src and dst use the same register, this function returns a writemask that + * indicates wich components are read by src. Otherwise zero is returned. */ static unsigned int src_reads_dst_mask(struct rc_src_register src, struct rc_dst_register dst) @@ -563,10 +563,18 @@ static int presub_helper( * s->Inst->U.I.DstReg, because if it does we must not * remove s->Inst. */ for(i = 0; i < info->NumSrcRegs; i++) { - if(s->Inst->U.I.DstReg.WriteMask != - src_reads_dst_mask(inst->U.I.SrcReg[i], - s->Inst->U.I.DstReg)) { - continue; + unsigned int mask = src_reads_dst_mask( + inst->U.I.SrcReg[i], s->Inst->U.I.DstReg); + /* XXX We could be more aggressive here using + * presubtract. It is okay if SrcReg[i] only reads + * from some of the mask components. */ + if(s->Inst->U.I.DstReg.WriteMask != mask) { + if (s->Inst->U.I.DstReg.WriteMask & mask) { + can_remove = 0; + break; + } else { + continue; + } } if (cant_sub || !can_use_presub) { can_remove = 0; @@ -626,6 +634,21 @@ static void presub_replace_add(struct peephole_state *s, inst->U.I.SrcReg[src_index].Index = presub_opcode; } +static int is_presub_candidate(struct rc_instruction * inst) +{ + const struct rc_opcode_info * info = rc_get_opcode_info(inst->U.I.Opcode); + unsigned int i; + + if (inst->U.I.PreSub.Opcode != RC_PRESUB_NONE || inst->U.I.SaturateMode) + return 0; + + for(i = 0; i < info->NumSrcRegs; i++) { + if (src_reads_dst_mask(inst->U.I.SrcReg[i], inst->U.I.DstReg)) + return 0; + } + return 1; +} + static int peephole_add_presub_add( struct radeon_compiler * c, struct rc_instruction * inst_add) @@ -635,10 +658,7 @@ static int peephole_add_presub_add( unsigned int i; struct peephole_state s; - if (inst_add->U.I.PreSub.Opcode != RC_PRESUB_NONE) - return 0; - - if (inst_add->U.I.SaturateMode) + if (!is_presub_candidate(inst_add)) return 0; if (inst_add->U.I.SrcReg[0].Swizzle != inst_add->U.I.SrcReg[1].Swizzle) @@ -705,10 +725,7 @@ static int peephole_add_presub_inv( unsigned int i, swz, mask; struct peephole_state s; - if (inst_add->U.I.PreSub.Opcode != RC_PRESUB_NONE) - return 0; - - if (inst_add->U.I.SaturateMode) + if (!is_presub_candidate(inst_add)) return 0; mask = inst_add->U.I.DstReg.WriteMask; |