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-rw-r--r--mesalib/src/glsl/opt_constant_propagation.cpp890
1 files changed, 445 insertions, 445 deletions
diff --git a/mesalib/src/glsl/opt_constant_propagation.cpp b/mesalib/src/glsl/opt_constant_propagation.cpp
index 7c42b6191..af77e4906 100644
--- a/mesalib/src/glsl/opt_constant_propagation.cpp
+++ b/mesalib/src/glsl/opt_constant_propagation.cpp
@@ -1,445 +1,445 @@
-/*
- * 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 opt_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;
- this->initial_values = write_mask;
- }
-
- acp_entry(const acp_entry *src)
- {
- this->var = src->var;
- this->write_mask = src->write_mask;
- this->constant = src->constant;
- this->initial_values = src->initial_values;
- }
-
- ir_variable *var;
- ir_constant *constant;
- unsigned write_mask;
-
- /** Mask of values initially available in the constant. */
- unsigned initial_values;
-};
-
-
-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 = ralloc_context(0);
- this->acp = new(mem_ctx) exec_list;
- this->kills = new(mem_ctx) exec_list;
- }
- ~ir_constant_propagation_visitor()
- {
- ralloc_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->initial_values & (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(ralloc_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));
- }
-
- 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)
- 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;
-}
+/*
+ * 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 opt_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;
+ this->initial_values = write_mask;
+ }
+
+ acp_entry(const acp_entry *src)
+ {
+ this->var = src->var;
+ this->write_mask = src->write_mask;
+ this->constant = src->constant;
+ this->initial_values = src->initial_values;
+ }
+
+ ir_variable *var;
+ ir_constant *constant;
+ unsigned write_mask;
+
+ /** Mask of values initially available in the constant. */
+ unsigned initial_values;
+};
+
+
+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 = ralloc_context(0);
+ this->acp = new(mem_ctx) exec_list;
+ this->kills = new(mem_ctx) exec_list;
+ }
+ ~ir_constant_propagation_visitor()
+ {
+ ralloc_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->initial_values & (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(ralloc_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));
+ }
+
+ 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)
+ 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;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 04:23:27 +0000