ExpressionInliner::ExpressionInliner():
r_ref_info(0),
- r_any_inlined(false),
r_trivial(false),
- mutating(false),
+ access_read(true),
+ access_write(false),
iteration_init(false),
iteration_body(0),
r_oper(0)
bool ExpressionInliner::apply(Stage &s)
{
s.content.visit(*this);
- return r_any_inlined;
-}
-
-void ExpressionInliner::inline_expression(Expression &expr, RefPtr<Expression> &ptr)
-{
- ptr = expr.clone();
- r_any_inlined = true;
-}
-
-void ExpressionInliner::visit(Block &block)
-{
- TraversingVisitor::visit(block);
- for(map<string, VariableDeclaration *>::iterator i=block.variables.begin(); i!=block.variables.end(); ++i)
- {
- map<Assignment::Target, ExpressionInfo>::iterator j = expressions.lower_bound(i->second);
- for(; (j!=expressions.end() && j->first.declaration==i->second); )
+ bool any_inlined = false;
+ for(list<ExpressionInfo>::iterator i=expressions.begin(); i!=expressions.end(); ++i)
+ if(i->expression && (i->trivial || i->uses.size()==1))
{
- if(j->second.expression && j->second.inline_point)
- inline_expression(*j->second.expression, *j->second.inline_point);
-
- expressions.erase(j++);
+ for(vector<ExpressionUse>::iterator j=i->uses.begin(); j!=i->uses.end(); ++j)
+ if(!j->blocked)
+ {
+ *j->reference = i->expression->clone();
+ any_inlined = true;
+ }
}
- }
- /* Expressions assigned in this block may depend on local variables of the
- block. If this is a conditionally executed block, the assignments might not
- always happen. Mark the expressions as not available to any outer blocks. */
- for(map<Assignment::Target, ExpressionInfo>::iterator i=expressions.begin(); i!=expressions.end(); ++i)
- if(i->second.assign_scope==&block)
- i->second.available = false;
+ return any_inlined;
}
void ExpressionInliner::visit(RefPtr<Expression> &expr)
{
r_ref_info = 0;
expr->visit(*this);
- if(r_ref_info && r_ref_info->expression && r_ref_info->available)
+ if(r_ref_info && r_ref_info->expression)
{
+ ExpressionUse use;
+ use.reference = &expr;
+ use.ref_scope = current_block;
+ use.blocked = access_write;
+
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
+ /* Block inlining of non-trivial expressions 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;
+ for(Block *i=iteration_body->parent; (!use.blocked && i); i=i->parent)
+ use.blocked = (i==r_ref_info->assign_scope);
}
- if(r_ref_info->trivial)
- inline_expression(*r_ref_info->expression, expr);
- 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 = &expr;
+ /* Block inlining assignments from from inner scopes. The assignment may
+ depend on local variables of that scope or may not always be executed. */
+ for(Block *i=r_ref_info->assign_scope->parent; (!use.blocked && i); i=i->parent)
+ use.blocked = (i==current_block);
+
+ r_ref_info->uses.push_back(use);
}
r_oper = expr->oper;
r_ref_info = 0;
void ExpressionInliner::visit(VariableReference &var)
{
- if(var.declaration)
+ if(var.declaration && access_read)
{
- map<Assignment::Target, 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;
- }
+ map<Assignment::Target, ExpressionInfo *>::iterator i = assignments.find(var.declaration);
+ if(i!=assignments.end())
+ r_ref_info = i->second;
}
}
void ExpressionInliner::visit(UnaryExpression &unary)
{
- SetFlag set_target(mutating, mutating || unary.oper->token[1]=='+' || unary.oper->token[1]=='-');
+ SetFlag set_write(access_write, access_write || unary.oper->token[1]=='+' || unary.oper->token[1]=='-');
visit(unary.expression);
r_trivial = false;
}
{
visit(binary.left);
{
- SetFlag clear_target(mutating, false);
+ SetFlag clear_write(access_write, false);
visit(binary.right);
}
r_trivial = false;
void ExpressionInliner::visit(Assignment &assign)
{
{
- SetFlag set_target(mutating);
+ SetFlag set_read(access_read, assign.oper->token[0]!='=');
+ SetFlag set_write(access_write);
visit(assign.left);
}
r_oper = 0;
+ r_trivial = true;
visit(assign.right);
- map<Assignment::Target, ExpressionInfo>::iterator i = expressions.find(assign.target);
- if(i!=expressions.end())
+ map<Assignment::Target, ExpressionInfo *>::iterator i = assignments.find(assign.target);
+ if(i!=assignments.end())
{
- /* 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.available = true;
+ if(iteration_body && i->second->expression)
+ {
+ /* Block inlining into previous references within the iteration
+ statement. On iterations after the first they would refer to the
+ assignment within the iteration. */
+ for(vector<ExpressionUse>::iterator j=i->second->uses.begin(); j!=i->second->uses.end(); ++j)
+ for(Block *k=j->ref_scope; (!j->blocked && k); k=k->parent)
+ j->blocked = (k==iteration_body);
+ }
+
+ expressions.push_back(ExpressionInfo());
+ ExpressionInfo &info = expressions.back();
+ info.target = assign.target;
+ // Self-referencing assignments can't be inlined without additional work.
+ if(!assign.self_referencing)
+ info.expression = assign.right;
+ info.assign_scope = current_block;
+ info.trivial = r_trivial;
+
+ i->second = &info;
}
r_trivial = false;
analyze and non-trivial expressions could be expensive to inline. */
if((current_block->parent || (constant && r_trivial)) && var.interface.empty())
{
- ExpressionInfo &info = expressions[&var];
+ expressions.push_back(ExpressionInfo());
+ ExpressionInfo &info = expressions.back();
+ info.target = &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());
+ if(!iteration_init)
+ info.expression = var.init_expression;
info.assign_scope = current_block;
info.trivial = r_trivial;
+
+ assignments[&var] = &info;
}
}
projects / libs / gl.git / blobdiff