glsl: Refactor logic for determining whether to lower return statements.

Previously, do_lower_jumps.cpp determined whether to lower return
statements in ir_lower_jumps_visitor::should_lower_jumps().  Moved
this logic to ir_lower_jumps_visitor::visit(ir_function_signature *),
so that it can be used in determining whether to lower a return
statement at the end of a function.
(cherry picked from commit dbaa2e627e)
This commit is contained in:
Paul Berry 2011-07-01 11:59:32 -07:00 committed by Marek Olšák
parent 934c7a0661
commit d1786cea1c

View file

@ -146,16 +146,17 @@ struct function_record
ir_function_signature* signature;
ir_variable* return_flag; /* used to break out of all loops and then jump to the return instruction */
ir_variable* return_value;
bool is_main;
bool lower_return;
unsigned nesting_depth;
function_record(ir_function_signature* p_signature = 0)
function_record(ir_function_signature* p_signature = 0,
bool lower_return = false)
{
this->signature = p_signature;
this->return_flag = 0;
this->return_value = 0;
this->nesting_depth = 0;
this->is_main = this->signature && (strcmp(this->signature->function_name(), "main") == 0);
this->lower_return = lower_return;
}
ir_variable* get_return_flag()
@ -274,10 +275,8 @@ struct ir_lower_jumps_visitor : public ir_control_flow_visitor {
/* never lower return at the end of a this->function */
if(this->function.nesting_depth == 0 && ir->get_next()->is_tail_sentinel())
lower = false;
else if (this->function.is_main)
lower = lower_main_return;
else
lower = lower_sub_return;
lower = this->function.lower_return;
break;
}
return lower;
@ -530,9 +529,15 @@ lower_continue:
assert(!this->function.signature);
assert(!this->loop.loop);
bool lower_return;
if (strcmp(ir->function_name(), "main") == 0)
lower_return = lower_main_return;
else
lower_return = lower_sub_return;
function_record saved_function = this->function;
loop_record saved_loop = this->loop;
this->function = function_record(ir);
this->function = function_record(ir, lower_return);
this->loop = loop_record(ir);
assert(!this->loop.loop);