archive/php-src
1
0
Fork 0
mirror of https://github.com/php/php-src.git synced 2025-08-15 21:48:51 +02:00
Code Issues Projects Releases Packages Wiki Activity Actions 3

Update IR

Browse source 
IR commit: cd6fe296e8f39af70d5532d955add261899f2639
This commit is contained in:
Dmitry Stogov 2024-03-07 19:38:03 +03:00
parent a541b95a5e
commit 34f27e1b1f
1 changed files with 23 additions and 11 deletions
Download patch file Download diff file Expand all files Collapse all files

34
ext/opcache/jit/ir/ir_cfg.c
View file

@ -1856,9 +1856,15 @@ static int ir_edge_info_cmp(const void *b1, const void *b2)
if (e1->freq != e2->freq) {
return e1->freq < e2->freq ? 1 : -1;
}
/* In case of equal frequences prefer to keep the existing order */
/* In case of equal frequencies, try to avoid penalization of one of the "equal" paths by
* preferring the first RPO successor (in conditional branches) and the last RPO predecessor
* (in merge points).
*
* See "Static Basic Block Reordering Heuristics for Implicit Control Flow in Baseline JITs"
* Polito Guillermo, Ducasse Stephane, and Tesone Pablo (2021)
*/
if (e1->from != e2->from) {
return e1->from - e2->from;
return e2->from - e1->from;
} else {
return e1->to - e2->to;
}
@ -2037,7 +2043,7 @@ static int ir_schedule_blocks_bottom_up(ir_ctx *ctx)
chains[b].prev = b;
}
/* 2. Collect information about BBs and EDGEs freqeuncies */
/* 2. Collect information about BBs and EDGEs frequencies */
edges = ir_mem_malloc(sizeof(ir_edge_info) * max_edges_count);
bb_freq = ir_mem_calloc(ctx->cfg_blocks_count + 1, sizeof(float));
bb_freq[1] = 1.0f;
@ -2052,8 +2058,8 @@ restart:
uint32_t *p = ctx->cfg_edges + bb->predecessors;
for (; n > 0; p++, n--) {
uint32_t predecessor = *p;
/* Basic Blocks are ordered in a way that usual predecessors ids are less then successors.
* So we may comapre blocks ids (predecessor < b) instead of a more expensive check for back edge
/* Basic Blocks are ordered in a way that usual predecessors ids are less than successors.
* So we may compare blocks ids (predecessor < b) instead of a more expensive check for back edge
* (b != predecessor && ctx->cfg_blocks[predecessor].loop_header != b)
*/
if (predecessor < b) {
@ -2255,14 +2261,14 @@ restart:
ir_bitqueue_free(&worklist);
ir_mem_free(visited);
/* 2. Sort EDGEs according to their frequentcies */
/* 2. Sort EDGEs according to their frequencies */
qsort(edges, edges_count, sizeof(ir_edge_info), ir_edge_info_cmp);
#if IR_DEBUG_BB_SCHEDULE_EDGES
ir_dump_edges(ctx, edges_count, edges);
#endif
/* 3. Process EDGEs in the decrising frequentcy order and join the connected chains */
/* 3. Process EDGEs in the decreasing frequency order and join the connected chains */
for (e = edges, i = edges_count; i > 0; e++, i--) {
uint32_t dst = chains[e->to].head;
if (dst == e->to) {
@ -2341,8 +2347,8 @@ restart:
#endif
}
/* 5. Group chains accoring to the most frequnt edge between them */
// TODO: Try to find a better heuristc
/* 5. Group chains according to the most frequent edge between them */
// TODO: Try to find a better heuristic
for (e = edges, i = edges_count; i > 0; e++, i--) {
#if !IR_DEBUG_BB_SCHEDULE_GRAPH
if (!e->from) continue;
@ -2525,8 +2531,14 @@ int ir_schedule_blocks(ir_ctx *ctx)
{
if (ctx->cfg_blocks_count <= 2) {
return 1;
// TODO: make the choise between top-down and bottom-up algorithm configurable
} else if (UNEXPECTED(ctx->flags2 & IR_IRREDUCIBLE_CFG) || ctx->cfg_blocks_count > 256) {
}
/* The bottom-up Pettis-Hansen algorithm is expensive - O(n^3),
* use it only for relatively small functions.
*
* TODO: make the choice between top-down and bottom-up algorithm configurable
*/
if (UNEXPECTED(ctx->flags2 & IR_IRREDUCIBLE_CFG) || ctx->cfg_blocks_count > 256) {
return ir_schedule_blocks_top_down(ctx);
} else {
return ir_schedule_blocks_bottom_up(ctx);