#include <msp/core/raii.h>
+#include <msp/strings/format.h>
#include "optimize.h"
using namespace std;
namespace SL {
InlineableFunctionLocator::InlineableFunctionLocator():
- in_function(0)
+ current_function(0),
+ return_count(0)
{ }
void InlineableFunctionLocator::visit(FunctionCall &call)
{
FunctionDeclaration *def = call.declaration;
- if(def && def->definition!=def)
+ if(def)
def = def->definition;
if(def)
{
unsigned &count = refcounts[def];
++count;
- if(count>1 || def==in_function)
+ /* Don't inline functions which are called more than once or are called
+ recursively. */
+ if(count>1 || def==current_function)
inlineable.erase(def);
}
void InlineableFunctionLocator::visit(FunctionDeclaration &func)
{
unsigned &count = refcounts[func.definition];
- if(!count && func.parameters.empty())
+ if(count<=1 && func.parameters.empty())
inlineable.insert(func.definition);
- SetForScope<FunctionDeclaration *> set(in_function, &func);
+ SetForScope<FunctionDeclaration *> set(current_function, &func);
+ return_count = 0;
TraversingVisitor::visit(func);
}
+void InlineableFunctionLocator::visit(Conditional &cond)
+{
+ TraversingVisitor::visit(cond);
+ inlineable.erase(current_function);
+}
+
+void InlineableFunctionLocator::visit(Iteration &iter)
+{
+ TraversingVisitor::visit(iter);
+ inlineable.erase(current_function);
+}
+
+void InlineableFunctionLocator::visit(Return &ret)
+{
+ TraversingVisitor::visit(ret);
+ if(return_count)
+ inlineable.erase(current_function);
+ ++return_count;
+}
+
+
+InlineContentInjector::InlineContentInjector():
+ source_func(0),
+ remap_names(false),
+ deps_only(false)
+{ }
+
+const string &InlineContentInjector::apply(Stage &stage, FunctionDeclaration &target_func, Block &tgt_blk, const NodeList<Statement>::iterator &ins_pt, FunctionDeclaration &src)
+{
+ target_block = &tgt_blk;
+ source_func = &src;
+ for(NodeList<Statement>::iterator i=src.body.body.begin(); i!=src.body.body.end(); ++i)
+ {
+ r_inlined_statement = 0;
+ (*i)->visit(*this);
+ if(!r_inlined_statement)
+ r_inlined_statement = (*i)->clone();
+
+ SetFlag set_remap(remap_names);
+ r_inlined_statement->visit(*this);
+ tgt_blk.body.insert(ins_pt, r_inlined_statement);
+ }
+
+ NodeReorderer().apply(stage, target_func, dependencies);
+
+ return r_result_name;
+}
+
+string InlineContentInjector::create_unused_name(const string &base, bool always_prefix)
+{
+ string result = base;
+ if(always_prefix || target_block->variables.count(result))
+ result = format("_%s_%s", source_func->name, base);
+ unsigned initial_size = result.size();
+ for(unsigned i=1; target_block->variables.count(result); ++i)
+ {
+ result.erase(initial_size);
+ result += format("_%d", i);
+ }
+ return result;
+}
+
+void InlineContentInjector::visit(VariableReference &var)
+{
+ if(remap_names)
+ {
+ map<string, VariableDeclaration *>::const_iterator i = variable_map.find(var.name);
+ if(i!=variable_map.end())
+ var.name = i->second->name;
+ }
+ else if(var.declaration)
+ {
+ SetFlag set_deps(deps_only);
+ dependencies.insert(var.declaration);
+ var.declaration->visit(*this);
+ }
+}
+
+void InlineContentInjector::visit(InterfaceBlockReference &iface)
+{
+ if(!remap_names && iface.declaration)
+ {
+ SetFlag set_deps(deps_only);
+ dependencies.insert(iface.declaration);
+ iface.declaration->visit(*this);
+ }
+}
+
+void InlineContentInjector::visit(FunctionCall &call)
+{
+ if(!remap_names && call.declaration)
+ dependencies.insert(call.declaration);
+ TraversingVisitor::visit(call);
+}
+
+void InlineContentInjector::visit(VariableDeclaration &var)
+{
+ TraversingVisitor::visit(var);
+
+ if(var.type_declaration)
+ {
+ SetFlag set_deps(deps_only);
+ dependencies.insert(var.type_declaration);
+ var.type_declaration->visit(*this);
+ }
+
+ if(!remap_names && !deps_only)
+ {
+ RefPtr<VariableDeclaration> inlined_var = var.clone();
+ inlined_var->name = create_unused_name(var.name, false);
+ r_inlined_statement = inlined_var;
+
+ variable_map[var.name] = inlined_var.get();
+ }
+}
+
+void InlineContentInjector::visit(Return &ret)
+{
+ TraversingVisitor::visit(ret);
+
+ if(ret.expression)
+ {
+ /* Create a new variable to hold the return value of the inlined
+ function. */
+ r_result_name = create_unused_name("return", true);
+ RefPtr<VariableDeclaration> var = new VariableDeclaration;
+ var->source = ret.source;
+ var->line = ret.line;
+ var->type = source_func->return_type;
+ var->name = r_result_name;
+ var->init_expression = ret.expression->clone();
+ r_inlined_statement = var;
+ }
+}
+
FunctionInliner::FunctionInliner():
- extract_result(0)
+ current_function(0),
+ r_any_inlined(false)
{ }
-void FunctionInliner::apply(Stage &stage)
+bool FunctionInliner::apply(Stage &s)
{
- inlineable = InlineableFunctionLocator().apply(stage);
- stage.content.visit(*this);
+ stage = &s;
+ inlineable = InlineableFunctionLocator().apply(s);
+ r_any_inlined = false;
+ s.content.visit(*this);
+ return r_any_inlined;
}
void FunctionInliner::visit_and_inline(RefPtr<Expression> &ptr)
{
- inline_result = 0;
+ r_inline_result = 0;
ptr->visit(*this);
- if(inline_result)
- ptr = inline_result;
+ if(r_inline_result)
+ {
+ ptr = r_inline_result;
+ r_any_inlined = true;
+ }
+ r_inline_result = 0;
}
void FunctionInliner::visit(Block &block)
{
- if(extract_result)
- --extract_result;
-
+ SetForScope<Block *> set_block(current_block, &block);
+ SetForScope<NodeList<Statement>::iterator> save_insert_point(insert_point, block.body.begin());
for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
{
+ insert_point = i;
(*i)->visit(*this);
- if(extract_result)
- --extract_result;
}
}
void FunctionInliner::visit(UnaryExpression &unary)
{
visit_and_inline(unary.expression);
- inline_result = 0;
}
void FunctionInliner::visit(BinaryExpression &binary)
{
visit_and_inline(binary.left);
visit_and_inline(binary.right);
- inline_result = 0;
}
void FunctionInliner::visit(MemberAccess &memacc)
{
visit_and_inline(memacc.left);
- inline_result = 0;
}
void FunctionInliner::visit(FunctionCall &call)
visit_and_inline(*i);
FunctionDeclaration *def = call.declaration;
- if(def && def->definition!=def)
+ if(def)
def = def->definition;
if(def && inlineable.count(def))
{
- extract_result = 2;
- def->visit(*this);
+ string result_name = InlineContentInjector().apply(*stage, *current_function, *current_block, insert_point, *def);
+
+ // This will later get removed by UnusedVariableRemover.
+ if(result_name.empty())
+ result_name = "msp_unused_from_inline";
+
+ RefPtr<VariableReference> ref = new VariableReference;
+ ref->name = result_name;
+ r_inline_result = ref;
+
+ /* Inlined variables need to be resolved before this function can be
+ inlined further. */
+ inlineable.erase(current_function);
}
- else
- inline_result = 0;
+}
+
+void FunctionInliner::visit(ExpressionStatement &expr)
+{
+ visit_and_inline(expr.expression);
}
void FunctionInliner::visit(VariableDeclaration &var)
{
if(var.init_expression)
visit_and_inline(var.init_expression);
- inline_result = 0;
}
-void FunctionInliner::visit(Return &ret)
+void FunctionInliner::visit(FunctionDeclaration &func)
{
- TraversingVisitor::visit(ret);
+ SetForScope<FunctionDeclaration *> set_func(current_function, &func);
+ TraversingVisitor::visit(func);
+}
+
+void FunctionInliner::visit(Conditional &cond)
+{
+ visit_and_inline(cond.condition);
+ cond.body.visit(*this);
+}
+
+void FunctionInliner::visit(Iteration &iter)
+{
+ /* Visit the initialization statement before entering the loop body so the
+ inlined statements get inserted outside. */
+ if(iter.init_statement)
+ iter.init_statement->visit(*this);
- if(extract_result)
- inline_result = ret.expression->clone();
+ SetForScope<Block *> set_block(current_block, &iter.body);
+ /* Skip the condition and loop expression parts because they're not properly
+ inside the body block. Inlining anything into them will require a more
+ comprehensive transformation. */
+ iter.body.visit(*this);
+}
+
+void FunctionInliner::visit(Return &ret)
+{
+ if(ret.expression)
+ visit_and_inline(ret.expression);
}
-ConstantConditionEliminator::ConstantConditionEliminator():
- record_only(false)
+ExpressionInliner::ExpressionInfo::ExpressionInfo():
+ expression(0),
+ assign_scope(0),
+ inline_point(0),
+ inner_oper(0),
+ outer_oper(0),
+ inline_on_rhs(false),
+ trivial(false),
+ available(true)
{ }
-void ConstantConditionEliminator::apply(Stage &stage)
+
+ExpressionInliner::ExpressionInliner():
+ r_ref_info(0),
+ r_any_inlined(false),
+ r_trivial(false),
+ mutating(false),
+ iteration_init(false),
+ iteration_body(0),
+ r_oper(0)
+{ }
+
+bool ExpressionInliner::apply(Stage &s)
{
- stage.content.visit(*this);
- NodeRemover().apply(stage, nodes_to_remove);
+ s.content.visit(*this);
+ return r_any_inlined;
}
-void ConstantConditionEliminator::visit(Block &block)
+void ExpressionInliner::visit_and_record(RefPtr<Expression> &ptr, const Operator *outer_oper, bool on_rhs)
{
- SetForScope<Block *> set_block(current_block, &block);
- for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
+ r_ref_info = 0;
+ ptr->visit(*this);
+ if(r_ref_info && r_ref_info->expression && r_ref_info->available)
{
- insert_point = i;
- (*i)->visit(*this);
+ if(iteration_body && !r_ref_info->trivial)
+ {
+ /* Don't inline non-trivial expressions which were assigned outside
+ an iteration statement. The iteration may run multiple times, which
+ would cause the expression to also be evaluated multiple times. */
+ Block *i = r_ref_info->assign_scope;
+ for(; (i && i!=iteration_body); i=i->parent) ;
+ if(!i)
+ return;
+ }
+
+ r_ref_info->outer_oper = outer_oper;
+ if(r_ref_info->trivial)
+ inline_expression(*r_ref_info->expression, ptr, outer_oper, r_ref_info->inner_oper, on_rhs);
+ else
+ {
+ /* Record the inline point for a non-trivial expression but don't
+ inline it yet. It might turn out it shouldn't be inlined after all. */
+ r_ref_info->inline_point = &ptr;
+ r_ref_info->inline_on_rhs = on_rhs;
+ }
}
+ r_ref_info = 0;
+}
+
+void ExpressionInliner::inline_expression(Expression &expr, RefPtr<Expression> &ptr, const Operator *outer_oper, const Operator *inner_oper, bool on_rhs)
+{
+ unsigned outer_precedence = (outer_oper ? outer_oper->precedence : 20);
+ unsigned inner_precedence = (inner_oper ? inner_oper->precedence : 0);
+
+ bool needs_parentheses = (inner_precedence>=outer_precedence);
+ if(inner_oper && inner_oper==outer_oper)
+ // Omit parentheses if the operator's natural grouping works out.
+ needs_parentheses = (inner_oper->assoc!=Operator::ASSOCIATIVE && on_rhs!=(inner_oper->assoc==Operator::RIGHT_TO_LEFT));
+
+ if(needs_parentheses)
+ {
+ RefPtr<ParenthesizedExpression> parexpr = new ParenthesizedExpression;
+ parexpr->expression = expr.clone();
+ ptr = parexpr;
+ }
+ else
+ ptr = expr.clone();
- for(map<string, VariableDeclaration *>::const_iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
- variable_values.erase(i->second);
+ r_any_inlined = true;
}
-void ConstantConditionEliminator::visit(UnaryExpression &unary)
+void ExpressionInliner::visit(Block &block)
{
- if(VariableReference *var = dynamic_cast<VariableReference *>(unary.expression.get()))
- if(unary.oper=="++" || unary.oper=="--")
- variable_values.erase(var->declaration);
+ TraversingVisitor::visit(block);
+
+ for(map<VariableDeclaration *, ExpressionInfo>::iterator i=expressions.begin(); i!=expressions.end(); )
+ {
+ map<string, VariableDeclaration *>::iterator j = block.variables.find(i->first->name);
+ if(j!=block.variables.end() && j->second==i->first)
+ {
+ if(i->second.expression && i->second.inline_point)
+ inline_expression(*i->second.expression, *i->second.inline_point, i->second.outer_oper, i->second.inner_oper, i->second.inline_on_rhs);
+
+ expressions.erase(i++);
+ }
+ else
+ {
+ /* The expression was assigned in this block and may depend on local
+ variables of the block. If this is a conditionally executed block,
+ the assignment might not always happen. Mark the expression as not
+ available to any outer blocks. */
+ if(i->second.assign_scope==&block)
+ i->second.available = false;
+
+ ++i;
+ }
+ }
}
-void ConstantConditionEliminator::visit(Assignment &assign)
+void ExpressionInliner::visit(VariableReference &var)
{
- variable_values.erase(assign.target_declaration);
+ if(var.declaration)
+ {
+ map<VariableDeclaration *, ExpressionInfo>::iterator i = expressions.find(var.declaration);
+ if(i!=expressions.end())
+ {
+ /* If a non-trivial expression is referenced multiple times, don't
+ inline it. */
+ if(i->second.inline_point && !i->second.trivial)
+ i->second.expression = 0;
+ /* Mutating expressions are analogous to self-referencing assignments
+ and prevent inlining. */
+ if(mutating)
+ i->second.expression = 0;
+ r_ref_info = &i->second;
+ }
+ }
}
-void ConstantConditionEliminator::visit(VariableDeclaration &var)
+void ExpressionInliner::visit(MemberAccess &memacc)
{
- if((var.constant || current_block->parent) && var.init_expression)
- variable_values[&var] = var.init_expression.get();
+ visit_and_record(memacc.left, memacc.oper, false);
+ r_oper = memacc.oper;
+ r_trivial = false;
}
-void ConstantConditionEliminator::visit(Conditional &cond)
+void ExpressionInliner::visit(UnaryExpression &unary)
+{
+ SetFlag set_target(mutating, mutating || unary.oper->token[1]=='+' || unary.oper->token[1]=='-');
+ visit_and_record(unary.expression, unary.oper, false);
+ r_oper = unary.oper;
+ r_trivial = false;
+}
+
+void ExpressionInliner::visit(BinaryExpression &binary)
{
- if(!record_only)
+ visit_and_record(binary.left, binary.oper, false);
+ {
+ SetFlag clear_target(mutating, false);
+ visit_and_record(binary.right, binary.oper, true);
+ }
+ r_oper = binary.oper;
+ r_trivial = false;
+}
+
+void ExpressionInliner::visit(Assignment &assign)
+{
+ {
+ SetFlag set_target(mutating);
+ visit_and_record(assign.left, assign.oper, false);
+ }
+ r_oper = 0;
+ visit_and_record(assign.right, assign.oper, true);
+
+ if(assign.target_declaration)
{
- ExpressionEvaluator eval(variable_values);
- cond.condition->visit(eval);
- if(eval.is_result_valid())
+ map<VariableDeclaration *, ExpressionInfo>::iterator i = expressions.find(assign.target_declaration);
+ if(i!=expressions.end())
{
- Block &block = (eval.get_result() ? cond.body : cond.else_body);
- current_block->body.splice(insert_point, block.body);
- nodes_to_remove.insert(&cond);
- return;
+ /* Self-referencing assignments can't be inlined without additional
+ work. Just clear any previous expression. */
+ i->second.expression = (assign.self_referencing ? 0 : assign.right.get());
+ i->second.assign_scope = current_block;
+ i->second.inline_point = 0;
+ i->second.inner_oper = r_oper;
+ i->second.available = true;
}
}
+ r_oper = assign.oper;
+ r_trivial = false;
+}
+
+void ExpressionInliner::visit(FunctionCall &call)
+{
+ for(NodeArray<Expression>::iterator i=call.arguments.begin(); i!=call.arguments.end(); ++i)
+ visit_and_record(*i, 0, false);
+ r_oper = 0;
+ r_trivial = false;
+}
+
+void ExpressionInliner::visit(VariableDeclaration &var)
+{
+ r_oper = 0;
+ r_trivial = true;
+ if(var.init_expression)
+ visit_and_record(var.init_expression, 0, false);
+
+ bool constant = var.constant;
+ if(constant && var.layout)
+ {
+ for(vector<Layout::Qualifier>::const_iterator i=var.layout->qualifiers.begin(); (constant && i!=var.layout->qualifiers.end()); ++i)
+ constant = (i->name!="constant_id");
+ }
+
+ /* Only inline global variables if they're constant and have trivial
+ initializers. Non-constant variables could change in ways which are hard to
+ analyze and non-trivial expressions could be expensive to inline. */
+ if((current_block->parent || (constant && r_trivial)) && var.interface.empty())
+ {
+ ExpressionInfo &info = expressions[&var];
+ /* Assume variables declared in an iteration initialization statement
+ will have their values change throughout the iteration. */
+ info.expression = (iteration_init ? 0 : var.init_expression.get());
+ info.assign_scope = current_block;
+ info.inner_oper = r_oper;
+ info.trivial = r_trivial;
+ }
+}
+
+void ExpressionInliner::visit(Conditional &cond)
+{
+ visit_and_record(cond.condition, 0, false);
+ cond.body.visit(*this);
+}
+
+void ExpressionInliner::visit(Iteration &iter)
+{
+ SetForScope<Block *> set_block(current_block, &iter.body);
+ if(iter.init_statement)
+ {
+ SetFlag set_init(iteration_init);
+ iter.init_statement->visit(*this);
+ }
+
+ SetForScope<Block *> set_body(iteration_body, &iter.body);
+ if(iter.condition)
+ iter.condition->visit(*this);
+ iter.body.visit(*this);
+ if(iter.loop_expression)
+ iter.loop_expression->visit(*this);
+}
+
+void ExpressionInliner::visit(Return &ret)
+{
+ if(ret.expression)
+ visit_and_record(ret.expression, 0, false);
+}
+
+
+void ConstantConditionEliminator::apply(Stage &stage)
+{
+ stage.content.visit(*this);
+ NodeRemover().apply(stage, nodes_to_remove);
+}
+
+void ConstantConditionEliminator::visit(Block &block)
+{
+ SetForScope<Block *> set_block(current_block, &block);
+ for(NodeList<Statement>::iterator i=block.body.begin(); i!=block.body.end(); ++i)
+ {
+ insert_point = i;
+ (*i)->visit(*this);
+ }
+}
+
+void ConstantConditionEliminator::visit(Conditional &cond)
+{
+ ExpressionEvaluator eval;
+ cond.condition->visit(eval);
+ if(eval.is_result_valid())
+ {
+ Block &block = (eval.get_result() ? cond.body : cond.else_body);
+ current_block->body.splice(insert_point, block.body);
+ nodes_to_remove.insert(&cond);
+ return;
+ }
+
TraversingVisitor::visit(cond);
}
void ConstantConditionEliminator::visit(Iteration &iter)
{
- if(!record_only)
+ if(iter.condition)
{
- if(iter.condition)
+ /* If the loop condition is always false on the first iteration, the
+ entire loop can be removed */
+ ExpressionEvaluator::ValueMap values;
+ if(VariableDeclaration *var = dynamic_cast<VariableDeclaration *>(iter.init_statement.get()))
+ values[var] = var->init_expression.get();
+ ExpressionEvaluator eval(values);
+ iter.condition->visit(eval);
+ if(eval.is_result_valid() && !eval.get_result())
{
- /* If the loop condition is always false on the first iteration, the
- entire loop can be removed */
- if(iter.init_statement)
- iter.init_statement->visit(*this);
- ExpressionEvaluator eval(variable_values);
- iter.condition->visit(eval);
- if(eval.is_result_valid() && !eval.get_result())
- {
- nodes_to_remove.insert(&iter);
- return;
- }
+ nodes_to_remove.insert(&iter);
+ return;
}
-
- /* Record all assignments that occur inside the loop body so those
- variables won't be considered as constant */
- SetFlag set_record(record_only);
- TraversingVisitor::visit(iter);
}
TraversingVisitor::visit(iter);
-
- if(VariableDeclaration *init_decl = dynamic_cast<VariableDeclaration *>(iter.init_statement.get()))
- variable_values.erase(init_decl);
}
{ }
+bool UnusedTypeRemover::apply(Stage &stage)
+{
+ stage.content.visit(*this);
+ NodeRemover().apply(stage, unused_nodes);
+ return !unused_nodes.empty();
+}
+
+void UnusedTypeRemover::visit(Literal &literal)
+{
+ unused_nodes.erase(literal.type);
+}
+
+void UnusedTypeRemover::visit(UnaryExpression &unary)
+{
+ unused_nodes.erase(unary.type);
+ TraversingVisitor::visit(unary);
+}
+
+void UnusedTypeRemover::visit(BinaryExpression &binary)
+{
+ unused_nodes.erase(binary.type);
+ TraversingVisitor::visit(binary);
+}
+
+void UnusedTypeRemover::visit(FunctionCall &call)
+{
+ unused_nodes.erase(call.type);
+ TraversingVisitor::visit(call);
+}
+
+void UnusedTypeRemover::visit(BasicTypeDeclaration &type)
+{
+ if(type.base_type)
+ unused_nodes.erase(type.base_type);
+ unused_nodes.insert(&type);
+}
+
+void UnusedTypeRemover::visit(ImageTypeDeclaration &type)
+{
+ if(type.base_type)
+ unused_nodes.erase(type.base_type);
+ unused_nodes.insert(&type);
+}
+
+void UnusedTypeRemover::visit(StructDeclaration &strct)
+{
+ unused_nodes.insert(&strct);
+ TraversingVisitor::visit(strct);
+}
+
+void UnusedTypeRemover::visit(VariableDeclaration &var)
+{
+ unused_nodes.erase(var.type_declaration);
+}
+
+void UnusedTypeRemover::visit(InterfaceBlock &iface)
+{
+ unused_nodes.erase(iface.type_declaration);
+}
+
+void UnusedTypeRemover::visit(FunctionDeclaration &func)
+{
+ unused_nodes.erase(func.return_type_declaration);
+ TraversingVisitor::visit(func);
+}
+
+
UnusedVariableRemover::UnusedVariableRemover():
aggregate(0),
- assignment(0),
+ r_assignment(0),
assignment_target(false),
- assign_to_subscript(false)
+ r_assign_to_subfield(false),
+ r_side_effects(false)
{ }
bool UnusedVariableRemover::apply(Stage &stage)
BlockVariableMap &global_variables = variables.back();
for(BlockVariableMap::iterator i=global_variables.begin(); i!=global_variables.end(); ++i)
{
- if(i->first->interface=="out" && (stage.type==Stage::FRAGMENT || i->first->linked_declaration || !i->first->name.compare(0, 3, "gl_")))
+ string interface = i->first->interface;
+ bool linked = i->first->linked_declaration;
+ map<VariableDeclaration *, Node *>::iterator j = aggregates.find(i->first);
+ if(j!=aggregates.end())
+ if(InterfaceBlock *iface = dynamic_cast<InterfaceBlock *>(j->second))
+ {
+ interface = iface->interface;
+ linked = iface->linked_block;
+ }
+
+ /* Don't remove output variables which are used by the next stage or the
+ graphics API. */
+ if(interface=="out" && (stage.type==Stage::FRAGMENT || linked || !i->first->name.compare(0, 3, "gl_")))
continue;
+
+ // Mark other unreferenced global variables as unused.
if(!i->second.referenced)
{
unused_nodes.insert(i->first);
if(var.declaration && !assignment_target)
{
VariableInfo &var_info = variables.back()[var.declaration];
- var_info.assignments.clear();
+ // Previous assignments are used by this reference.
+ clear_assignments(var_info, false);
var_info.referenced = true;
}
}
+void UnusedVariableRemover::visit(InterfaceBlockReference &iface)
+{
+ unused_nodes.erase(iface.declaration);
+}
+
void UnusedVariableRemover::visit(MemberAccess &memacc)
{
+ if(assignment_target)
+ r_assign_to_subfield = true;
TraversingVisitor::visit(memacc);
unused_nodes.erase(memacc.declaration);
}
+void UnusedVariableRemover::visit(UnaryExpression &unary)
+{
+ TraversingVisitor::visit(unary);
+ if(unary.oper->token[1]=='+' || unary.oper->token[1]=='-')
+ r_side_effects = true;
+}
+
void UnusedVariableRemover::visit(BinaryExpression &binary)
{
- if(binary.oper=="[")
+ if(binary.oper->token[0]=='[')
{
if(assignment_target)
- assign_to_subscript = true;
+ r_assign_to_subfield = true;
binary.left->visit(*this);
- SetForScope<bool> set(assignment_target, false);
+ SetFlag set(assignment_target, false);
binary.right->visit(*this);
}
else
void UnusedVariableRemover::visit(Assignment &assign)
{
{
- assign_to_subscript = false;
- SetForScope<bool> set(assignment_target, !assign.self_referencing);
+ SetFlag set(assignment_target, !assign.self_referencing);
assign.left->visit(*this);
}
assign.right->visit(*this);
- assignment = &assign;
+ r_assignment = &assign;
+ r_side_effects = true;
+}
+
+void UnusedVariableRemover::visit(FunctionCall &call)
+{
+ TraversingVisitor::visit(call);
+ /* Treat function calls as having side effects so expression statements
+ consisting of nothing but a function call won't be optimized away. */
+ r_side_effects = true;
}
void UnusedVariableRemover::record_assignment(VariableDeclaration &var, Node &node, bool chained)
{
VariableInfo &var_info = variables.back()[&var];
+ /* An assignment which completely replaces the value of the variable causes
+ any previous unreferenced assignments to be unused. */
if(!chained)
clear_assignments(var_info, true);
var_info.assignments.push_back(&node);
void UnusedVariableRemover::visit(ExpressionStatement &expr)
{
- assignment = 0;
+ r_assignment = 0;
+ r_assign_to_subfield = false;
+ r_side_effects = false;
TraversingVisitor::visit(expr);
- if(assignment && assignment->target_declaration)
- record_assignment(*assignment->target_declaration, expr, (assignment->self_referencing || assign_to_subscript));
+ if(r_assignment && r_assignment->target_declaration)
+ record_assignment(*r_assignment->target_declaration, expr, (r_assignment->self_referencing || r_assign_to_subfield));
+ if(!r_side_effects)
+ unused_nodes.insert(&expr);
}
void UnusedVariableRemover::visit(StructDeclaration &strct)
{
SetForScope<Node *> set(aggregate, &strct);
- unused_nodes.insert(&strct);
TraversingVisitor::visit(strct);
}
if(var.init_expression)
record_assignment(var, *var.init_expression, false);
}
- unused_nodes.erase(var.type_declaration);
TraversingVisitor::visit(var);
}
{
SetForScope<Node *> set(aggregate, &iface);
unused_nodes.insert(&iface);
- TraversingVisitor::visit(iface);
+ iface.struct_declaration->members.visit(*this);
}
void UnusedVariableRemover::visit(FunctionDeclaration &func)
func.body.visit(*this);
BlockVariableMap &block_variables = variables.back();
+
+ /* Mark global variables as conditionally assigned so assignments in other
+ functions won't be removed. */
for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
- i->second.conditionally_assigned = true;
+ if(!i->second.local)
+ i->second.conditionally_assigned = true;
+
+ /* Always treat function parameters as referenced. Removing unused
+ parameters is not currently supported. */
for(NodeArray<VariableDeclaration>::iterator i=func.parameters.begin(); i!=func.parameters.end(); ++i)
block_variables[i->get()].referenced = true;
+
merge_down_variables();
}
{
if(!i->second.referenced)
unused_nodes.insert(i->first);
- clear_assignments(i->second, i->first->interface!="out");
+ /* Any unreferenced assignments when a variable runs out of scope
+ become unused. */
+ clear_assignments(i->second, true);
continue;
}
parent_variables.insert(*i);
else
{
+ // Merge a non-local variable's state into the parent scope.
if(i->second.referenced || !i->second.conditionally_assigned)
clear_assignments(j->second, !i->second.referenced);
j->second.conditionally_assigned = i->second.conditionally_assigned;
swap(variables.back(), if_variables);
cond.else_body.visit(*this);
+ // Combine variables from both branches.
BlockVariableMap &else_variables = variables.back();
for(BlockVariableMap::iterator i=else_variables.begin(); i!=else_variables.end(); ++i)
{
BlockVariableMap::iterator j = if_variables.find(i->first);
if(j!=if_variables.end())
{
+ // The variable was found in both branches.
i->second.assignments.insert(i->second.assignments.end(), j->second.assignments.begin(), j->second.assignments.end());
i->second.conditionally_assigned |= j->second.conditionally_assigned;
if_variables.erase(j);
}
else
+ // Mark variables found in only one branch as conditionally assigned.
i->second.conditionally_assigned = true;
}
+ /* Move variables which were only used in the if block into the combined
+ block. */
for(BlockVariableMap::iterator i=if_variables.begin(); i!=if_variables.end(); ++i)
{
i->second.conditionally_assigned = true;
{
variables.push_back(BlockVariableMap());
TraversingVisitor::visit(iter);
-
- BlockVariableMap &block_variables = variables.back();
- for(BlockVariableMap::iterator i=block_variables.begin(); i!=block_variables.end(); ++i)
- if(!i->second.local && i->second.referenced)
- i->second.assignments.clear();
-
merge_down_variables();
}
projects / libs / gl.git / blobdiff