19434a0749f26c640305f68ef85d17a31063a5705Ian Romanick/* 29434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * Copyright © 2010 Intel Corporation 39434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 49434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * Permission is hereby granted, free of charge, to any person obtaining a 59434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * copy of this software and associated documentation files (the "Software"), 69434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * to deal in the Software without restriction, including without limitation 79434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * the rights to use, copy, modify, merge, publish, distribute, sublicense, 89434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * and/or sell copies of the Software, and to permit persons to whom the 99434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * Software is furnished to do so, subject to the following conditions: 109434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 119434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * The above copyright notice and this permission notice (including the next 129434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * paragraph) shall be included in all copies or substantial portions of the 139434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * Software. 149434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 159434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 169434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 179434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 189434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 199434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 209434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 219434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * DEALINGS IN THE SOFTWARE. 229434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 239434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 249434a0749f26c640305f68ef85d17a31063a5705Ian Romanick#include "glsl_types.h" 259434a0749f26c640305f68ef85d17a31063a5705Ian Romanick#include "loop_analysis.h" 269434a0749f26c640305f68ef85d17a31063a5705Ian Romanick#include "ir_hierarchical_visitor.h" 279434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 289434a0749f26c640305f68ef85d17a31063a5705Ian Romanickstatic bool is_loop_terminator(ir_if *ir); 299434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 309434a0749f26c640305f68ef85d17a31063a5705Ian Romanickstatic bool all_expression_operands_are_loop_constant(ir_rvalue *, 319434a0749f26c640305f68ef85d17a31063a5705Ian Romanick hash_table *); 329434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 339434a0749f26c640305f68ef85d17a31063a5705Ian Romanickstatic ir_rvalue *get_basic_induction_increment(ir_assignment *, hash_table *); 349434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 359434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 369434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_state::loop_state() 379434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 389434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->ht = hash_table_ctor(0, hash_table_pointer_hash, 399434a0749f26c640305f68ef85d17a31063a5705Ian Romanick hash_table_pointer_compare); 40d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke this->mem_ctx = ralloc_context(NULL); 4158c988ada56114b56477983f66b4039219f1a82cEric Anholt this->loop_found = false; 429434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 439434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 449434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 459434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_state::~loop_state() 469434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 479434a0749f26c640305f68ef85d17a31063a5705Ian Romanick hash_table_dtor(this->ht); 48d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke ralloc_free(this->mem_ctx); 499434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 509434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 519434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 529434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable_state * 539434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_state::insert(ir_loop *ir) 549434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 559434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable_state *ls = new(this->mem_ctx) loop_variable_state; 5658c988ada56114b56477983f66b4039219f1a82cEric Anholt 579434a0749f26c640305f68ef85d17a31063a5705Ian Romanick hash_table_insert(this->ht, ls, ir); 5858c988ada56114b56477983f66b4039219f1a82cEric Anholt this->loop_found = true; 599434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 609434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return ls; 619434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 629434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 639434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 649434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable_state * 659434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_state::get(const ir_loop *ir) 669434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 679434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return (loop_variable_state *) hash_table_find(this->ht, ir); 689434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 699434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 709434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 719434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable * 729434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable_state::get(const ir_variable *ir) 739434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 749434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return (loop_variable *) hash_table_find(this->var_hash, ir); 759434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 769434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 779434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 789434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable * 799434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable_state::insert(ir_variable *var) 809434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 81d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke void *mem_ctx = ralloc_parent(this); 82d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke loop_variable *lv = rzalloc(mem_ctx, loop_variable); 839434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 849434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->var = var; 859434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 869434a0749f26c640305f68ef85d17a31063a5705Ian Romanick hash_table_insert(this->var_hash, lv, lv->var); 879434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->variables.push_tail(lv); 889434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 899434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return lv; 909434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 919434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 929434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 939434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_terminator * 949434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_variable_state::insert(ir_if *if_stmt) 959434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 96d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke void *mem_ctx = ralloc_parent(this); 97d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke loop_terminator *t = rzalloc(mem_ctx, loop_terminator); 989434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 999434a0749f26c640305f68ef85d17a31063a5705Ian Romanick t->ir = if_stmt; 1009434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->terminators.push_tail(t); 1019434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1029434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return t; 1039434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 1049434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1059434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1069434a0749f26c640305f68ef85d17a31063a5705Ian Romanickclass loop_analysis : public ir_hierarchical_visitor { 1079434a0749f26c640305f68ef85d17a31063a5705Ian Romanickpublic: 1089434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_analysis(); 1099434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1103bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick virtual ir_visitor_status visit(ir_loop_jump *); 1119434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit(ir_dereference_variable *); 1129434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1130405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke virtual ir_visitor_status visit_enter(ir_call *); 1140405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke 1159434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit_enter(ir_loop *); 1169434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit_leave(ir_loop *); 1179434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit_enter(ir_assignment *); 1189434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit_leave(ir_assignment *); 1199434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit_enter(ir_if *); 1209434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit_leave(ir_if *); 1219434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1229434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_state *loops; 1239434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1249434a0749f26c640305f68ef85d17a31063a5705Ian Romanick int if_statement_depth; 1259434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1269434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_assignment *current_assignment; 1279434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1289434a0749f26c640305f68ef85d17a31063a5705Ian Romanick exec_list state; 1299434a0749f26c640305f68ef85d17a31063a5705Ian Romanick}; 1309434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1319434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1329434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::loop_analysis() 1339434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 1349434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->loops = new loop_state; 1359434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1369434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->if_statement_depth = 0; 1379434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->current_assignment = NULL; 1389434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 1399434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1409434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1419434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 1423bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanickloop_analysis::visit(ir_loop_jump *ir) 1433bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick{ 1443bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick (void) ir; 1453bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick 1463bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick assert(!this->state.is_empty()); 1473bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick 1483bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick loop_variable_state *const ls = 1493bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick (loop_variable_state *) this->state.get_head(); 1503bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick 1513bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick ls->num_loop_jumps++; 1523bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick 1533bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick return visit_continue; 1543bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick} 1553bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick 1563bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanick 1573bcfafcf0320ee5407716ff67062e80d162760d4Ian Romanickir_visitor_status 1580405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunkeloop_analysis::visit_enter(ir_call *ir) 1590405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke{ 1600405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke /* If we're not somewhere inside a loop, there's nothing to do. */ 1610405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke if (this->state.is_empty()) 1620405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke return visit_continue; 1630405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke 1640405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke loop_variable_state *const ls = 1650405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke (loop_variable_state *) this->state.get_head(); 1660405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke 1670405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke ls->contains_calls = true; 1680405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke return visit_continue_with_parent; 1690405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke} 1700405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke 1710405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke 1720405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunkeir_visitor_status 1739434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit(ir_dereference_variable *ir) 1749434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 1759434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* If we're not somewhere inside a loop, there's nothing to do. 1769434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 1779434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (this->state.is_empty()) 178956f049fd24eb5239361e68a1f27e1bebb3315a0Ian Romanick return visit_continue; 1799434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1809434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable_state *const ls = 1819434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (loop_variable_state *) this->state.get_head(); 1829434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1839434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_variable *var = ir->variable_referenced(); 1849434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable *lv = ls->get(var); 1859434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1869434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv == NULL) { 1879434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv = ls->insert(var); 1889434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->read_before_write = !this->in_assignee; 1899434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 1909434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1919434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (this->in_assignee) { 1929434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(this->current_assignment != NULL); 1939434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1949434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->conditional_assignment = (this->if_statement_depth > 0) 1959434a0749f26c640305f68ef85d17a31063a5705Ian Romanick || (this->current_assignment->condition != NULL); 1969434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 1979434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->first_assignment == NULL) { 1989434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(lv->num_assignments == 0); 1999434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2009434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->first_assignment = this->current_assignment; 2019434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 2029434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2039434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->num_assignments++; 2049434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } else if (lv->first_assignment == this->current_assignment) { 2059434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* This catches the case where the variable is used in the RHS of an 2069434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * assignment where it is also in the LHS. 2079434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 2089434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->read_before_write = true; 2099434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 2109434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2119434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 2129434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 2139434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2149434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 2159434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit_enter(ir_loop *ir) 2169434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 2179434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable_state *ls = this->loops->insert(ir); 2189434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->state.push_head(ls); 2199434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2209434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 2219434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 2229434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2239434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 2249434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit_leave(ir_loop *ir) 2259434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 2269434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable_state *const ls = 2279434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (loop_variable_state *) this->state.pop_head(); 2289434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2290405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke /* Function calls may contain side effects. These could alter any of our 2300405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * variables in ways that cannot be known, and may even terminate shader 2310405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * execution (say, calling discard in the fragment shader). So we can't 2320405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * rely on any of our analysis about assignments to variables. 2330405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * 2340405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * We could perform some conservative analysis (prove there's no statically 2350405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * possible assignment, etc.) but it isn't worth it for now; function 2360405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke * inlining will allow us to unroll loops anyway. 2370405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke */ 2380405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke if (ls->contains_calls) 2390405bd08ca0e01ebc68891ee1ff47d320983f775Kenneth Graunke return visit_continue; 2409434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2419434a0749f26c640305f68ef85d17a31063a5705Ian Romanick foreach_list(node, &ir->body_instructions) { 2429434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* Skip over declarations at the start of a loop. 2439434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 2449434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (((ir_instruction *) node)->as_variable()) 2459434a0749f26c640305f68ef85d17a31063a5705Ian Romanick continue; 2469434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2479434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_if *if_stmt = ((ir_instruction *) node)->as_if(); 2489434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2499434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if ((if_stmt != NULL) && is_loop_terminator(if_stmt)) 2509434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ls->insert(if_stmt); 2519434a0749f26c640305f68ef85d17a31063a5705Ian Romanick else 2529434a0749f26c640305f68ef85d17a31063a5705Ian Romanick break; 2539434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 2549434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2559434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2569434a0749f26c640305f68ef85d17a31063a5705Ian Romanick foreach_list_safe(node, &ls->variables) { 2579434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable *lv = (loop_variable *) node; 2589434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2599434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* Move variables that are already marked as being loop constant to 2609434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * a separate list. These trivially don't need to be tested. 2619434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 2629434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->is_loop_constant()) { 2639434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->remove(); 2649434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ls->constants.push_tail(lv); 2659434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 2669434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 2679434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2689434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* Each variable assigned in the loop that isn't already marked as being loop 2699434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * constant might still be loop constant. The requirements at this point 2709434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * are: 2719434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 2729434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * - Variable is written before it is read. 2739434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 2749434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * - Only one assignment to the variable. 2759434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 2769434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * - All operands on the RHS of the assignment are also loop constants. 2779434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 2789434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * The last requirement is the reason for the progress loop. A variable 2799434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * marked as a loop constant on one pass may allow other variables to be 2809434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * marked as loop constant on following passes. 2819434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 2829434a0749f26c640305f68ef85d17a31063a5705Ian Romanick bool progress; 2839434a0749f26c640305f68ef85d17a31063a5705Ian Romanick do { 2849434a0749f26c640305f68ef85d17a31063a5705Ian Romanick progress = false; 2859434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2869434a0749f26c640305f68ef85d17a31063a5705Ian Romanick foreach_list_safe(node, &ls->variables) { 2879434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable *lv = (loop_variable *) node; 2889434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2899434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->conditional_assignment || (lv->num_assignments > 1)) 2909434a0749f26c640305f68ef85d17a31063a5705Ian Romanick continue; 2919434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2929434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* Process the RHS of the assignment. If all of the variables 2939434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * accessed there are loop constants, then add this 2949434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 2959434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_rvalue *const rhs = lv->first_assignment->rhs; 2969434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (all_expression_operands_are_loop_constant(rhs, ls->var_hash)) { 2979434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->rhs_clean = true; 2989434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 2999434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->is_loop_constant()) { 3009434a0749f26c640305f68ef85d17a31063a5705Ian Romanick progress = true; 3019434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3029434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->remove(); 3039434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ls->constants.push_tail(lv); 3049434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 3059434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 3069434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 3079434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } while (progress); 3089434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3099434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* The remaining variables that are not loop invariant might be loop 3109434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * induction variables. 3119434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3129434a0749f26c640305f68ef85d17a31063a5705Ian Romanick foreach_list_safe(node, &ls->variables) { 3139434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable *lv = (loop_variable *) node; 3149434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3159434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* If there is more than one assignment to a variable, it cannot be a 3169434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * loop induction variable. This isn't strictly true, but this is a 3179434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * very simple induction variable detector, and it can't handle more 3189434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * complex cases. 3199434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3209434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->num_assignments > 1) 3219434a0749f26c640305f68ef85d17a31063a5705Ian Romanick continue; 3229434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3239434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* All of the variables with zero assignments in the loop are loop 3249434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * invariant, and they should have already been filtered out. 3259434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3269434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(lv->num_assignments == 1); 3279434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(lv->first_assignment != NULL); 3289434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3299434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* The assignmnet to the variable in the loop must be unconditional. 3309434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3319434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->conditional_assignment) 3329434a0749f26c640305f68ef85d17a31063a5705Ian Romanick continue; 3339434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3349434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* Basic loop induction variables have a single assignment in the loop 3359434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * that has the form 'VAR = VAR + i' or 'VAR = VAR - i' where i is a 3369434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * loop invariant. 3379434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3389434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_rvalue *const inc = 3399434a0749f26c640305f68ef85d17a31063a5705Ian Romanick get_basic_induction_increment(lv->first_assignment, ls->var_hash); 3409434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (inc != NULL) { 3419434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->iv_scale = NULL; 3429434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->biv = lv->var; 3439434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->increment = inc; 3449434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3459434a0749f26c640305f68ef85d17a31063a5705Ian Romanick lv->remove(); 3469434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ls->induction_variables.push_tail(lv); 3479434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 3489434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 3499434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3509434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 3519434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 3529434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3539434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 3549434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit_enter(ir_if *ir) 3559434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 3569434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (void) ir; 3579434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3589434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (!this->state.is_empty()) 3599434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->if_statement_depth++; 3609434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3619434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 3629434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 3639434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3649434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 3659434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit_leave(ir_if *ir) 3669434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 3679434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (void) ir; 3689434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3699434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (!this->state.is_empty()) 3709434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->if_statement_depth--; 3719434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3729434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 3739434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 3749434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3759434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 3769434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit_enter(ir_assignment *ir) 3779434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 3789434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* If we're not somewhere inside a loop, there's nothing to do. 3799434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3809434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (this->state.is_empty()) 3819434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue_with_parent; 3829434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3839434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->current_assignment = ir; 3849434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3859434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 3869434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 3879434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3889434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_visitor_status 3899434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_analysis::visit_leave(ir_assignment *ir) 3909434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 3919434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* Since the visit_enter exits with visit_continue_with_parent for this 3929434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * case, the loop state stack should never be empty here. 3939434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 3949434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(!this->state.is_empty()); 3959434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3969434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(this->current_assignment == ir); 3979434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->current_assignment = NULL; 3989434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 3999434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 4009434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 4019434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4029434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4039434a0749f26c640305f68ef85d17a31063a5705Ian Romanickclass examine_rhs : public ir_hierarchical_visitor { 4049434a0749f26c640305f68ef85d17a31063a5705Ian Romanickpublic: 4059434a0749f26c640305f68ef85d17a31063a5705Ian Romanick examine_rhs(hash_table *loop_variables) 4069434a0749f26c640305f68ef85d17a31063a5705Ian Romanick { 4079434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->only_uses_loop_constants = true; 4089434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->loop_variables = loop_variables; 4099434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 4109434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4119434a0749f26c640305f68ef85d17a31063a5705Ian Romanick virtual ir_visitor_status visit(ir_dereference_variable *ir) 4129434a0749f26c640305f68ef85d17a31063a5705Ian Romanick { 4139434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable *lv = 4149434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (loop_variable *) hash_table_find(this->loop_variables, ir->var); 4159434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4169434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(lv != NULL); 4179434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4189434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (lv->is_loop_constant()) { 4199434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_continue; 4209434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } else { 4219434a0749f26c640305f68ef85d17a31063a5705Ian Romanick this->only_uses_loop_constants = false; 4229434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return visit_stop; 4239434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 4249434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 4259434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4269434a0749f26c640305f68ef85d17a31063a5705Ian Romanick hash_table *loop_variables; 4279434a0749f26c640305f68ef85d17a31063a5705Ian Romanick bool only_uses_loop_constants; 4289434a0749f26c640305f68ef85d17a31063a5705Ian Romanick}; 4299434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4309434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4319434a0749f26c640305f68ef85d17a31063a5705Ian Romanickbool 4329434a0749f26c640305f68ef85d17a31063a5705Ian Romanickall_expression_operands_are_loop_constant(ir_rvalue *ir, hash_table *variables) 4339434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 4349434a0749f26c640305f68ef85d17a31063a5705Ian Romanick examine_rhs v(variables); 4359434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4369434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir->accept(&v); 4379434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4389434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return v.only_uses_loop_constants; 4399434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 4409434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4419434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4429434a0749f26c640305f68ef85d17a31063a5705Ian Romanickir_rvalue * 4439434a0749f26c640305f68ef85d17a31063a5705Ian Romanickget_basic_induction_increment(ir_assignment *ir, hash_table *var_hash) 4449434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 4459434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* The RHS must be a binary expression. 4469434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 4479434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_expression *const rhs = ir->rhs->as_expression(); 4489434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if ((rhs == NULL) 4499434a0749f26c640305f68ef85d17a31063a5705Ian Romanick || ((rhs->operation != ir_binop_add) 4509434a0749f26c640305f68ef85d17a31063a5705Ian Romanick && (rhs->operation != ir_binop_sub))) 4519434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return NULL; 4529434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4539434a0749f26c640305f68ef85d17a31063a5705Ian Romanick /* One of the of operands of the expression must be the variable assigned. 4549434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * If the operation is subtraction, the variable in question must be the 4559434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * "left" operand. 4569434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 4579434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_variable *const var = ir->lhs->variable_referenced(); 4589434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4599434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_variable *const op0 = rhs->operands[0]->variable_referenced(); 4609434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_variable *const op1 = rhs->operands[1]->variable_referenced(); 4619434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4629434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (((op0 != var) && (op1 != var)) 4639434a0749f26c640305f68ef85d17a31063a5705Ian Romanick || ((op1 == var) && (rhs->operation == ir_binop_sub))) 4649434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return NULL; 4659434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4669434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_rvalue *inc = (op0 == var) ? rhs->operands[1] : rhs->operands[0]; 4679434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 468f061524f0737bf59dad6ab9bb2e0015df804e4b5Ian Romanick if (inc->as_constant() == NULL) { 4699434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_variable *const inc_var = inc->variable_referenced(); 4709434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (inc_var != NULL) { 4719434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_variable *lv = 4729434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (loop_variable *) hash_table_find(var_hash, inc_var); 4739434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4749434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (!lv->is_loop_constant()) 4759434a0749f26c640305f68ef85d17a31063a5705Ian Romanick inc = NULL; 4769434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } else 4779434a0749f26c640305f68ef85d17a31063a5705Ian Romanick inc = NULL; 4789434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 4799434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4809434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if ((inc != NULL) && (rhs->operation == ir_binop_sub)) { 481d3073f58c17d8675a2ecdd5dfa83e5520c78e1a8Kenneth Graunke void *mem_ctx = ralloc_parent(ir); 4829434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4839434a0749f26c640305f68ef85d17a31063a5705Ian Romanick inc = new(mem_ctx) ir_expression(ir_unop_neg, 4849434a0749f26c640305f68ef85d17a31063a5705Ian Romanick inc->type, 4859434a0749f26c640305f68ef85d17a31063a5705Ian Romanick inc->clone(mem_ctx, NULL), 4869434a0749f26c640305f68ef85d17a31063a5705Ian Romanick NULL); 4879434a0749f26c640305f68ef85d17a31063a5705Ian Romanick } 4889434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4899434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return inc; 4909434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 4919434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4929434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 4939434a0749f26c640305f68ef85d17a31063a5705Ian Romanick/** 4949434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * Detect whether an if-statement is a loop terminating condition 4959434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 4969434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * Detects if-statements of the form 4979434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * 4989434a0749f26c640305f68ef85d17a31063a5705Ian Romanick * (if (expression bool ...) (break)) 4999434a0749f26c640305f68ef85d17a31063a5705Ian Romanick */ 5009434a0749f26c640305f68ef85d17a31063a5705Ian Romanickbool 5019434a0749f26c640305f68ef85d17a31063a5705Ian Romanickis_loop_terminator(ir_if *ir) 5029434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 5039434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (!ir->else_instructions.is_empty()) 5049434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return false; 5059434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5069434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_instruction *const inst = 5079434a0749f26c640305f68ef85d17a31063a5705Ian Romanick (ir_instruction *) ir->then_instructions.get_head(); 5089434a0749f26c640305f68ef85d17a31063a5705Ian Romanick assert(inst != NULL); 5099434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5109434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (inst->ir_type != ir_type_loop_jump) 5119434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return false; 5129434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5139434a0749f26c640305f68ef85d17a31063a5705Ian Romanick ir_loop_jump *const jump = (ir_loop_jump *) inst; 5149434a0749f26c640305f68ef85d17a31063a5705Ian Romanick if (jump->mode != ir_loop_jump::jump_break) 5159434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return false; 5169434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5179434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return true; 5189434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 5199434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5209434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5219434a0749f26c640305f68ef85d17a31063a5705Ian Romanickloop_state * 5229434a0749f26c640305f68ef85d17a31063a5705Ian Romanickanalyze_loop_variables(exec_list *instructions) 5239434a0749f26c640305f68ef85d17a31063a5705Ian Romanick{ 5249434a0749f26c640305f68ef85d17a31063a5705Ian Romanick loop_analysis v; 5259434a0749f26c640305f68ef85d17a31063a5705Ian Romanick 5269434a0749f26c640305f68ef85d17a31063a5705Ian Romanick v.run(instructions); 5279434a0749f26c640305f68ef85d17a31063a5705Ian Romanick return v.loops; 5289434a0749f26c640305f68ef85d17a31063a5705Ian Romanick} 529