Mesa (master): i965/fs: Remove dead_code_eliminate_local().
Matt Turner
mattst88 at kemper.freedesktop.org
Tue Apr 15 17:24:39 UTC 2014
Module: Mesa
Branch: master
Commit: 73400d8f70bab8549fb4cbcdc9ba905bf93b8716
URL: http://cgit.freedesktop.org/mesa/mesa/commit/?id=73400d8f70bab8549fb4cbcdc9ba905bf93b8716
Author: Matt Turner <mattst88 at gmail.com>
Date: Mon Apr 14 11:18:59 2014 -0700
i965/fs: Remove dead_code_eliminate_local().
Subsumed by the new dead_code_eliminate() function. No shader-db
changes.
Reviewed-by: Eric Anholt <eric at anholt.net>
---
src/mesa/drivers/dri/i965/brw_fs.cpp | 158 ----------------------------------
src/mesa/drivers/dri/i965/brw_fs.h | 1 -
2 files changed, 159 deletions(-)
diff --git a/src/mesa/drivers/dri/i965/brw_fs.cpp b/src/mesa/drivers/dri/i965/brw_fs.cpp
index c723bf0..88dfdfc 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.cpp
+++ b/src/mesa/drivers/dri/i965/brw_fs.cpp
@@ -2085,163 +2085,6 @@ fs_visitor::opt_algebraic()
return progress;
}
-struct dead_code_hash_key
-{
- int vgrf;
- int reg_offset;
-};
-
-static bool
-dead_code_hash_compare(const void *a, const void *b)
-{
- return memcmp(a, b, sizeof(struct dead_code_hash_key)) == 0;
-}
-
-static void
-clear_dead_code_hash(struct hash_table *ht)
-{
- struct hash_entry *entry;
-
- hash_table_foreach(ht, entry) {
- _mesa_hash_table_remove(ht, entry);
- }
-}
-
-static void
-insert_dead_code_hash(struct hash_table *ht,
- int vgrf, int reg_offset, fs_inst *inst)
-{
- /* We don't bother freeing keys, because they'll be GCed with the ht. */
- struct dead_code_hash_key *key = ralloc(ht, struct dead_code_hash_key);
-
- key->vgrf = vgrf;
- key->reg_offset = reg_offset;
-
- _mesa_hash_table_insert(ht, _mesa_hash_data(key, sizeof(*key)), key, inst);
-}
-
-static struct hash_entry *
-get_dead_code_hash_entry(struct hash_table *ht, int vgrf, int reg_offset)
-{
- struct dead_code_hash_key key;
-
- key.vgrf = vgrf;
- key.reg_offset = reg_offset;
-
- return _mesa_hash_table_search(ht, _mesa_hash_data(&key, sizeof(key)), &key);
-}
-
-static void
-remove_dead_code_hash(struct hash_table *ht,
- int vgrf, int reg_offset)
-{
- struct hash_entry *entry = get_dead_code_hash_entry(ht, vgrf, reg_offset);
- if (!entry)
- return;
-
- _mesa_hash_table_remove(ht, entry);
-}
-
-/**
- * Walks basic blocks, removing any regs that are written but not read before
- * being redefined.
- *
- * The dead_code_eliminate() function implements a global dead code
- * elimination, but it only handles the removing the last write to a register
- * if it's never read. This one can handle intermediate writes, but only
- * within a basic block.
- */
-bool
-fs_visitor::dead_code_eliminate_local()
-{
- struct hash_table *ht;
- bool progress = false;
-
- ht = _mesa_hash_table_create(mem_ctx, dead_code_hash_compare);
-
- if (ht == NULL) {
- return false;
- }
-
- foreach_list_safe(node, &this->instructions) {
- fs_inst *inst = (fs_inst *)node;
-
- /* At a basic block, empty the HT since we don't understand dataflow
- * here.
- */
- if (inst->is_control_flow()) {
- clear_dead_code_hash(ht);
- continue;
- }
-
- /* Clear the HT of any instructions that got read. */
- for (int i = 0; i < 3; i++) {
- fs_reg src = inst->src[i];
- if (src.file != GRF)
- continue;
-
- int read = 1;
- if (inst->is_send_from_grf())
- read = virtual_grf_sizes[src.reg] - src.reg_offset;
-
- for (int reg_offset = src.reg_offset;
- reg_offset < src.reg_offset + read;
- reg_offset++) {
- remove_dead_code_hash(ht, src.reg, reg_offset);
- }
- }
-
- /* Add any update of a GRF to the HT, removing a previous write if it
- * wasn't read.
- */
- if (inst->dst.file == GRF) {
- if (inst->regs_written > 1) {
- /* We don't know how to trim channels from an instruction's
- * writes, so we can't incrementally remove unread channels from
- * it. Just remove whatever it overwrites from the table
- */
- for (int i = 0; i < inst->regs_written; i++) {
- remove_dead_code_hash(ht,
- inst->dst.reg,
- inst->dst.reg_offset + i);
- }
- } else {
- struct hash_entry *entry =
- get_dead_code_hash_entry(ht, inst->dst.reg,
- inst->dst.reg_offset);
-
- if (entry) {
- if (inst->is_partial_write()) {
- /* For a partial write, we can't remove any previous dead code
- * candidate, since we're just modifying their result.
- */
- } else {
- /* We're completely updating a channel, and there was a
- * previous write to the channel that wasn't read. Kill it!
- */
- fs_inst *inst = (fs_inst *)entry->data;
- inst->remove();
- progress = true;
- }
-
- _mesa_hash_table_remove(ht, entry);
- }
-
- if (!inst->has_side_effects())
- insert_dead_code_hash(ht, inst->dst.reg, inst->dst.reg_offset,
- inst);
- }
- }
- }
-
- _mesa_hash_table_destroy(ht, NULL);
-
- if (progress)
- invalidate_live_intervals();
-
- return progress;
-}
-
bool
fs_visitor::compute_to_mrf()
{
@@ -3194,7 +3037,6 @@ fs_visitor::run()
progress = opt_cse() || progress;
progress = opt_copy_propagate() || progress;
progress = opt_peephole_predicated_break() || progress;
- progress = dead_code_eliminate_local() || progress;
progress = dead_code_eliminate() || progress;
progress = opt_peephole_sel() || progress;
progress = dead_control_flow_eliminate(this) || progress;
diff --git a/src/mesa/drivers/dri/i965/brw_fs.h b/src/mesa/drivers/dri/i965/brw_fs.h
index 3d21ee5..4c12bd7 100644
--- a/src/mesa/drivers/dri/i965/brw_fs.h
+++ b/src/mesa/drivers/dri/i965/brw_fs.h
@@ -374,7 +374,6 @@ public:
bool register_coalesce();
bool compute_to_mrf();
bool dead_code_eliminate();
- bool dead_code_eliminate_local();
bool remove_duplicate_mrf_writes();
bool virtual_grf_interferes(int a, int b);
void schedule_instructions(instruction_scheduler_mode mode);
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