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author | marha <marha@users.sourceforge.net> | 2010-12-28 16:10:20 +0000 |
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committer | marha <marha@users.sourceforge.net> | 2010-12-28 16:10:20 +0000 |
commit | 807c6931fe683fd844ceec1b023232181e6aae03 (patch) | |
tree | 1a131ed95fe2200d0ad33da8f7755a7ed2364adc /mesalib/src/glsl/ir_constant_propagation.cpp | |
parent | 973099dda7e49e5abe29819a7124b3b1e7bd8b92 (diff) | |
download | vcxsrv-807c6931fe683fd844ceec1b023232181e6aae03.tar.gz vcxsrv-807c6931fe683fd844ceec1b023232181e6aae03.tar.bz2 vcxsrv-807c6931fe683fd844ceec1b023232181e6aae03.zip |
xserver and mesa git update 28-12-2010
Diffstat (limited to 'mesalib/src/glsl/ir_constant_propagation.cpp')
-rw-r--r-- | mesalib/src/glsl/ir_constant_propagation.cpp | 437 |
1 files changed, 0 insertions, 437 deletions
diff --git a/mesalib/src/glsl/ir_constant_propagation.cpp b/mesalib/src/glsl/ir_constant_propagation.cpp deleted file mode 100644 index 5d875b7be..000000000 --- a/mesalib/src/glsl/ir_constant_propagation.cpp +++ /dev/null @@ -1,437 +0,0 @@ -/* - * Copyright © 2010 Intel Corporation - * - * Permission is hereby granted, free of charge, to any person obtaining a - * constant of this software and associated documentation files (the "Software"), - * to deal in the Software without restriction, including without limitation - * the rights to use, constant, modify, merge, publish, distribute, sublicense, - * and/or sell copies of the Software, and to permit persons to whom the - * Software is furnished to do so, subject to the following conditions: - * - * The above constantright notice and this permission notice (including the next - * paragraph) shall be included in all copies or substantial portions of the - * Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL - * THE AUTHORS OR CONSTANTRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING - * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER - * DEALINGS IN THE SOFTWARE. - */ - -/** - * \file ir_constant_propagation.cpp - * - * Tracks assignments of constants to channels of variables, and - * usage of those constant channels with direct usage of the constants. - * - * This can lead to constant folding and algebraic optimizations in - * those later expressions, while causing no increase in instruction - * count (due to constants being generally free to load from a - * constant push buffer or as instruction immediate values) and - * possibly reducing register pressure. - */ - -#include "ir.h" -#include "ir_visitor.h" -#include "ir_rvalue_visitor.h" -#include "ir_basic_block.h" -#include "ir_optimization.h" -#include "glsl_types.h" - -class acp_entry : public exec_node -{ -public: - acp_entry(ir_variable *var, unsigned write_mask, ir_constant *constant) - { - assert(var); - assert(constant); - this->var = var; - this->write_mask = write_mask; - this->constant = constant; - } - - ir_variable *var; - ir_constant *constant; - unsigned write_mask; -}; - - -class kill_entry : public exec_node -{ -public: - kill_entry(ir_variable *var, unsigned write_mask) - { - assert(var); - this->var = var; - this->write_mask = write_mask; - } - - ir_variable *var; - unsigned write_mask; -}; - -class ir_constant_propagation_visitor : public ir_rvalue_visitor { -public: - ir_constant_propagation_visitor() - { - progress = false; - mem_ctx = talloc_new(0); - this->acp = new(mem_ctx) exec_list; - this->kills = new(mem_ctx) exec_list; - } - ~ir_constant_propagation_visitor() - { - talloc_free(mem_ctx); - } - - virtual ir_visitor_status visit_enter(class ir_loop *); - virtual ir_visitor_status visit_enter(class ir_function_signature *); - virtual ir_visitor_status visit_enter(class ir_function *); - virtual ir_visitor_status visit_leave(class ir_assignment *); - virtual ir_visitor_status visit_enter(class ir_call *); - virtual ir_visitor_status visit_enter(class ir_if *); - - void add_constant(ir_assignment *ir); - void kill(ir_variable *ir, unsigned write_mask); - void handle_if_block(exec_list *instructions); - void handle_rvalue(ir_rvalue **rvalue); - - /** List of acp_entry: The available constants to propagate */ - exec_list *acp; - - /** - * List of kill_entry: The masks of variables whose values were - * killed in this block. - */ - exec_list *kills; - - bool progress; - - bool killed_all; - - void *mem_ctx; -}; - - -void -ir_constant_propagation_visitor::handle_rvalue(ir_rvalue **rvalue) -{ - if (this->in_assignee || !*rvalue) - return; - - const glsl_type *type = (*rvalue)->type; - if (!type->is_scalar() && !type->is_vector()) - return; - - ir_swizzle *swiz = NULL; - ir_dereference_variable *deref = (*rvalue)->as_dereference_variable(); - if (!deref) { - swiz = (*rvalue)->as_swizzle(); - if (!swiz) - return; - - deref = swiz->val->as_dereference_variable(); - if (!deref) - return; - } - - ir_constant_data data; - memset(&data, 0, sizeof(data)); - - for (unsigned int i = 0; i < type->components(); i++) { - int channel; - acp_entry *found = NULL; - - if (swiz) { - switch (i) { - case 0: channel = swiz->mask.x; break; - case 1: channel = swiz->mask.y; break; - case 2: channel = swiz->mask.z; break; - case 3: channel = swiz->mask.w; break; - default: assert(!"shouldn't be reached"); channel = 0; break; - } - } else { - channel = i; - } - - foreach_iter(exec_list_iterator, iter, *this->acp) { - acp_entry *entry = (acp_entry *)iter.get(); - if (entry->var == deref->var && entry->write_mask & (1 << channel)) { - found = entry; - break; - } - } - - if (!found) - return; - - int rhs_channel = 0; - for (int j = 0; j < 4; j++) { - if (j == channel) - break; - if (found->write_mask & (1 << j)) - rhs_channel++; - } - - switch (type->base_type) { - case GLSL_TYPE_FLOAT: - data.f[i] = found->constant->value.f[rhs_channel]; - break; - case GLSL_TYPE_INT: - data.i[i] = found->constant->value.i[rhs_channel]; - break; - case GLSL_TYPE_UINT: - data.u[i] = found->constant->value.u[rhs_channel]; - break; - case GLSL_TYPE_BOOL: - data.b[i] = found->constant->value.b[rhs_channel]; - break; - default: - assert(!"not reached"); - break; - } - } - - *rvalue = new(talloc_parent(deref)) ir_constant(type, &data); - this->progress = true; -} - -ir_visitor_status -ir_constant_propagation_visitor::visit_enter(ir_function_signature *ir) -{ - /* Treat entry into a function signature as a completely separate - * block. Any instructions at global scope will be shuffled into - * main() at link time, so they're irrelevant to us. - */ - exec_list *orig_acp = this->acp; - exec_list *orig_kills = this->kills; - bool orig_killed_all = this->killed_all; - - this->acp = new(mem_ctx) exec_list; - this->kills = new(mem_ctx) exec_list; - this->killed_all = false; - - visit_list_elements(this, &ir->body); - - this->kills = orig_kills; - this->acp = orig_acp; - this->killed_all = orig_killed_all; - - return visit_continue_with_parent; -} - -ir_visitor_status -ir_constant_propagation_visitor::visit_leave(ir_assignment *ir) -{ - if (this->in_assignee) - return visit_continue; - - kill(ir->lhs->variable_referenced(), ir->write_mask); - - add_constant(ir); - - return visit_continue; -} - -ir_visitor_status -ir_constant_propagation_visitor::visit_enter(ir_function *ir) -{ - (void) ir; - return visit_continue; -} - -ir_visitor_status -ir_constant_propagation_visitor::visit_enter(ir_call *ir) -{ - /* Do constant propagation on call parameters, but skip any out params */ - exec_list_iterator sig_param_iter = ir->get_callee()->parameters.iterator(); - foreach_iter(exec_list_iterator, iter, ir->actual_parameters) { - ir_variable *sig_param = (ir_variable *)sig_param_iter.get(); - ir_rvalue *param = (ir_rvalue *)iter.get(); - if (sig_param->mode != ir_var_out && sig_param->mode != ir_var_inout) { - ir_rvalue *new_param = param; - handle_rvalue(&new_param); - if (new_param != param) - param->replace_with(new_param); - else - param->accept(this); - } - sig_param_iter.next(); - } - - /* Since we're unlinked, we don't (necssarily) know the side effects of - * this call. So kill all copies. - */ - acp->make_empty(); - this->killed_all = true; - - return visit_continue_with_parent; -} - -void -ir_constant_propagation_visitor::handle_if_block(exec_list *instructions) -{ - exec_list *orig_acp = this->acp; - exec_list *orig_kills = this->kills; - bool orig_killed_all = this->killed_all; - - this->acp = new(mem_ctx) exec_list; - this->kills = new(mem_ctx) exec_list; - this->killed_all = false; - - /* Populate the initial acp with a constant of the original */ - foreach_iter(exec_list_iterator, iter, *orig_acp) { - acp_entry *a = (acp_entry *)iter.get(); - this->acp->push_tail(new(this->mem_ctx) acp_entry(a->var, a->write_mask, - a->constant)); - } - - visit_list_elements(this, instructions); - - if (this->killed_all) { - orig_acp->make_empty(); - } - - exec_list *new_kills = this->kills; - this->kills = orig_kills; - this->acp = orig_acp; - this->killed_all = this->killed_all || orig_killed_all; - - foreach_iter(exec_list_iterator, iter, *new_kills) { - kill_entry *k = (kill_entry *)iter.get(); - kill(k->var, k->write_mask); - } -} - -ir_visitor_status -ir_constant_propagation_visitor::visit_enter(ir_if *ir) -{ - ir->condition->accept(this); - handle_rvalue(&ir->condition); - - handle_if_block(&ir->then_instructions); - handle_if_block(&ir->else_instructions); - - /* handle_if_block() already descended into the children. */ - return visit_continue_with_parent; -} - -ir_visitor_status -ir_constant_propagation_visitor::visit_enter(ir_loop *ir) -{ - exec_list *orig_acp = this->acp; - exec_list *orig_kills = this->kills; - bool orig_killed_all = this->killed_all; - - /* FINISHME: For now, the initial acp for loops is totally empty. - * We could go through once, then go through again with the acp - * cloned minus the killed entries after the first run through. - */ - this->acp = new(mem_ctx) exec_list; - this->kills = new(mem_ctx) exec_list; - this->killed_all = false; - - visit_list_elements(this, &ir->body_instructions); - - if (this->killed_all) { - orig_acp->make_empty(); - } - - exec_list *new_kills = this->kills; - this->kills = orig_kills; - this->acp = orig_acp; - this->killed_all = this->killed_all || orig_killed_all; - - foreach_iter(exec_list_iterator, iter, *new_kills) { - kill_entry *k = (kill_entry *)iter.get(); - kill(k->var, k->write_mask); - } - - /* already descended into the children. */ - return visit_continue_with_parent; -} - -void -ir_constant_propagation_visitor::kill(ir_variable *var, unsigned write_mask) -{ - assert(var != NULL); - - /* We don't track non-vectors. */ - if (!var->type->is_vector() && !var->type->is_scalar()) - return; - - /* Remove any entries currently in the ACP for this kill. */ - foreach_iter(exec_list_iterator, iter, *this->acp) { - acp_entry *entry = (acp_entry *)iter.get(); - - if (entry->var == var) { - entry->write_mask &= ~write_mask; - if (entry->write_mask == 0) - entry->remove(); - } - } - - /* Add this writemask of the variable to the list of killed - * variables in this block. - */ - foreach_iter(exec_list_iterator, iter, *this->kills) { - kill_entry *entry = (kill_entry *)iter.get(); - - if (entry->var == var) { - entry->write_mask |= write_mask; - return; - } - } - /* Not already in the list. Make new entry. */ - this->kills->push_tail(new(this->mem_ctx) kill_entry(var, write_mask)); -} - -/** - * Adds an entry to the available constant list if it's a plain assignment - * of a variable to a variable. - */ -void -ir_constant_propagation_visitor::add_constant(ir_assignment *ir) -{ - acp_entry *entry; - - if (ir->condition) { - ir_constant *condition = ir->condition->as_constant(); - if (!condition || !condition->value.b[0]) - return; - } - - if (!ir->write_mask) - return; - - ir_dereference_variable *deref = ir->lhs->as_dereference_variable(); - ir_constant *constant = ir->rhs->as_constant(); - - if (!deref || !constant) - return; - - /* Only do constant propagation on vectors. Constant matrices, - * arrays, or structures would require more work elsewhere. - */ - if (!deref->var->type->is_vector() && !deref->var->type->is_scalar()) - return; - - entry = new(this->mem_ctx) acp_entry(deref->var, ir->write_mask, constant); - this->acp->push_tail(entry); -} - -/** - * Does a constant propagation pass on the code present in the instruction stream. - */ -bool -do_constant_propagation(exec_list *instructions) -{ - ir_constant_propagation_visitor v; - - visit_list_elements(&v, instructions); - - return v.progress; -} |