freedreno/ir3: only tex instructions have wrmask

At the ir3 level, we would assume that we could use wrmask to mask
off other components of an instruction returning a vecN when they are
not used.  Which would let RA use components not written for other live
values.  But this is only true for tex instructions.

Signed-off-by: Rob Clark <robdclark@chromium.org>
Reviewed-by: Kristian H. Kristensen <hoegsberg@google.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

diff --git a/src/freedreno/ir3/ir3_depth.c b/src/freedreno/ir3/ir3_depth.c
index bdd00693104507a8f3e5bc74f5a726a47b1b99fe..4bbd1e56d7c1156761a7603b330f3ee41ce97e9a 100644 (file)
--- a/src/freedreno/ir3/ir3_depth.c
+++ b/src/freedreno/ir3/ir3_depth.c
@@ -177,13 +177,10 @@ remove_unused_by_block(struct ir3_block *block)
                if (instr->flags & IR3_INSTR_UNUSED) {
                        if (instr->opc == OPC_META_SPLIT) {
                                struct ir3_instruction *src = ssa(instr->regs[1]);
-                               /* leave inputs alone.. we can't optimize out components of
-                                * an input, since the hw is still going to be writing all
-                                * of the components, and we could end up in a situation
-                                * where multiple inputs overlap.
+                               /* tex (cat5) instructions have a writemask, so we can
+                                * mask off unused components.  Other instructions do not.
                                 */
-                               if ((src->opc != OPC_META_INPUT) &&
-                                               (src->regs[0]->wrmask > 1)) {
+                               if (is_tex(src) && (src->regs[0]->wrmask > 1)) {
                                        src->regs[0]->wrmask &= ~(1 << instr->split.off);
 
                                        /* prune no-longer needed right-neighbors.  We could