0,0 → 1,149 |
/* |
* Copyright © 2010 Intel Corporation |
* |
* Permission is hereby granted, free of charge, to any person obtaining a |
* copy of this software and associated documentation files (the "Software"), |
* to deal in the Software without restriction, including without limitation |
* the rights to use, copy, 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 copyright 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 COPYRIGHT 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_basic_block.cpp |
* |
* Basic block analysis of instruction streams. |
*/ |
|
#include "ir.h" |
#include "ir_visitor.h" |
#include "ir_basic_block.h" |
#include "glsl_types.h" |
|
class ir_has_call_visitor : public ir_hierarchical_visitor { |
public: |
ir_has_call_visitor() |
{ |
has_call = false; |
} |
|
virtual ir_visitor_status visit_enter(ir_call *ir) |
{ |
(void) ir; |
has_call = true; |
return visit_stop; |
} |
|
bool has_call; |
}; |
|
bool |
ir_has_call(ir_instruction *ir) |
{ |
ir_has_call_visitor v; |
ir->accept(&v); |
return v.has_call; |
} |
|
/** |
* Calls a user function for every basic block in the instruction stream. |
* |
* Basic block analysis is pretty easy in our IR thanks to the lack of |
* unstructured control flow. We've got: |
* |
* ir_loop (for () {}, while () {}, do {} while ()) |
* ir_loop_jump ( |
* ir_if () {} |
* ir_return |
* ir_call() |
* |
* Note that the basic blocks returned by this don't encompass all |
* operations performed by the program -- for example, if conditions |
* don't get returned, nor do the assignments that will be generated |
* for ir_call parameters. |
*/ |
void call_for_basic_blocks(exec_list *instructions, |
void (*callback)(ir_instruction *first, |
ir_instruction *last, |
void *data), |
void *data) |
{ |
ir_instruction *leader = NULL; |
ir_instruction *last = NULL; |
|
foreach_iter(exec_list_iterator, iter, *instructions) { |
ir_instruction *ir = (ir_instruction *)iter.get(); |
ir_if *ir_if; |
ir_loop *ir_loop; |
ir_function *ir_function; |
|
if (!leader) |
leader = ir; |
|
if ((ir_if = ir->as_if())) { |
callback(leader, ir, data); |
leader = NULL; |
|
call_for_basic_blocks(&ir_if->then_instructions, callback, data); |
call_for_basic_blocks(&ir_if->else_instructions, callback, data); |
} else if ((ir_loop = ir->as_loop())) { |
callback(leader, ir, data); |
leader = NULL; |
call_for_basic_blocks(&ir_loop->body_instructions, callback, data); |
} else if (ir->as_return() || ir->as_call()) { |
callback(leader, ir, data); |
leader = NULL; |
} else if ((ir_function = ir->as_function())) { |
/* A function definition doesn't interrupt our basic block |
* since execution doesn't go into it. We should process the |
* bodies of its signatures for BBs, though. |
* |
* Note that we miss an opportunity for producing more |
* maximal BBs between the instructions that precede main() |
* and the body of main(). Perhaps those instructions ought |
* to live inside of main(). |
*/ |
foreach_iter(exec_list_iterator, fun_iter, *ir_function) { |
ir_function_signature *ir_sig; |
|
ir_sig = (ir_function_signature *)fun_iter.get(); |
|
call_for_basic_blocks(&ir_sig->body, callback, data); |
} |
} else if (ir->as_assignment()) { |
/* If there's a call in the expression tree being assigned, |
* then that ends the BB too. |
* |
* The assumption is that any consumer of the basic block |
* walker is fine with the fact that the call is somewhere in |
* the tree even if portions of the tree may be evaluated |
* after the call. |
* |
* A consumer that has an issue with this could not process |
* the last instruction of the basic block. If doing so, |
* expression flattener may be useful before using the basic |
* block finder to get more maximal basic blocks out. |
*/ |
if (ir_has_call(ir)) { |
callback(leader, ir, data); |
leader = NULL; |
} |
} |
last = ir; |
} |
if (leader) { |
callback(leader, last, data); |
} |
} |