From 615f6653b02829187bb8ddb38b12c34cb2976ef3 Mon Sep 17 00:00:00 2001 From: Eric Anholt Date: Fri, 3 Mar 2017 17:03:44 -0800 Subject: [PATCH] vc4: Fix register pressure cost estimates when a src appears twice. This ended up confusing the scheduler for things like fabs (implemented as fmaxabs x, x) or squaring a number, and it would try to avoid scheduling them because it appeared more expensive than other instructions. Fixes failure to register allocate in dEQP-GLES2.functional.uniform_api.random.3 with almost no shader-db effects (+.35% max temps) --- src/gallium/drivers/vc4/vc4_qir_schedule.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/src/gallium/drivers/vc4/vc4_qir_schedule.c b/src/gallium/drivers/vc4/vc4_qir_schedule.c index 89e6d1d..5118caf 100644 --- a/src/gallium/drivers/vc4/vc4_qir_schedule.c +++ b/src/gallium/drivers/vc4/vc4_qir_schedule.c @@ -434,10 +434,20 @@ get_register_pressure_cost(struct schedule_state *state, struct qinst *inst) cost--; for (int i = 0; i < qir_get_nsrc(inst); i++) { - if (inst->src[i].file == QFILE_TEMP && - !BITSET_TEST(state->temp_live, inst->src[i].index)) { - cost++; + if (inst->src[i].file != QFILE_TEMP || + BITSET_TEST(state->temp_live, inst->src[i].index)) { + continue; + } + + bool already_counted = false; + for (int j = 0; j < i; j++) { + if (inst->src[i].file == inst->src[j].file && + inst->src[i].index == inst->src[j].index) { + already_counted = true; + } } + if (!already_counted) + cost++; } return cost; -- 2.7.4