Files
triton/lib/codegen/barriers.cpp
2019-02-24 14:35:16 -05:00

91 lines
2.7 KiB
C++

#include <algorithm>
#include "triton/codegen/barriers.h"
#include "triton/codegen/allocation.h"
#include "triton/codegen/buffer_info.h"
#include "triton/ir/module.h"
#include "triton/ir/function.h"
#include "triton/ir/basic_block.h"
#include "triton/ir/instructions.h"
namespace triton {
namespace codegen{
bool barriers::intersect(const interval_vec_t &X, interval_t x) {
return std::any_of(X.begin(), X.end(), [&](const interval_t &y){
bool left_intersect = y.first <= x.first && x.first < y.second;
bool right_intersect = y.first <= x.second && x.second < y.second;
return left_intersect || right_intersect;
});
}
bool barriers::intersect(const interval_vec_t &X, const interval_vec_t &Y) {
return std::any_of(Y.begin(), Y.end(), [&](const interval_t &y){
return intersect(X, y);
});
}
void barriers::add_reference(ir::value *v, interval_vec_t &res){
if(dynamic_cast<ir::copy_to_shared_inst*>(v)){
unsigned offset = alloc_->get_offset(v);
unsigned num_bytes = alloc_->get_num_bytes(v);
res.push_back(interval_t(offset, offset + num_bytes));
}
}
void barriers::get_read_intervals(ir::instruction *i, interval_vec_t &res){
for(ir::value *op: i->ops())
add_reference(op, res);
}
void barriers::get_written_intervals(ir::instruction *i, interval_vec_t &res){
if(!dynamic_cast<ir::phi_node*>(i))
add_reference(i, res);
}
void barriers::insert_barrier(ir::instruction *instr, ir::builder &builder) {
if(auto *phi = dynamic_cast<ir::phi_node*>(instr)) {
std::set<ir::value*> incoming;
for(unsigned n = 0; n < phi->get_num_incoming(); n++){
ir::instruction *inc_val = dynamic_cast<ir::instruction*>(phi->get_incoming_value(n));
assert(inc_val);
if(incoming.insert(inc_val).second){
ir::basic_block *block = inc_val->get_parent();
builder.set_insert_point(block->get_inst_list().back());
builder.create_barrier();
}
}
}
else {
builder.set_insert_point(instr);
builder.create_barrier();
}
}
void barriers::add(ir::basic_block *block, interval_vec_t &not_synced, ir::builder &builder) {
ir::basic_block::inst_list_t instructions = block->get_inst_list();
for(ir::instruction *i: instructions){
interval_vec_t read, written;
get_read_intervals(i, read);
get_written_intervals(i, written);
if(intersect(not_synced, read)) {
not_synced.clear();
insert_barrier(i, builder);
}
std::copy(written.begin(), written.end(), std::back_inserter(not_synced));
}
}
void barriers::run(ir::module &mod) {
ir::builder &builder = mod.get_builder();
for(ir::function *fn: mod.get_function_list()){
// find barrier location
interval_vec_t not_synced;
for(ir::basic_block *block: fn->blocks())
add(block, not_synced, builder);
}
}
}
}