Files
MXCompiler/src/opt/regalloc.cpp
2024-10-22 14:27:40 +00:00

381 lines
16 KiB
C++

#include "regalloc.h"
#include "IR/IR_basic.h"
#include "cfg.h"
#include "confgraph.h"
#include "liveanalysis.h"
#include "phieliminate.h"
#include "tools.h"
void EnforcePhysicalRegs(CFGType &cfg) {
using namespace opt;
// process callee side
auto entry_node = cfg.entry;
auto func = cfg.corresponding_func;
std::unordered_set<std::string> missing_caller_saved_regs;
for (auto reg : caller_saved_regs) {
missing_caller_saved_regs.insert(reg);
}
for (size_t i = 0; i < 8 && i < func->args_full_name.size(); i++) {
auto new_def = std::make_shared<ForceDef>();
new_def->var_full = "%reg." + arg_regs[i];
new_def->ty = func->args[i];
auto new_move = std::make_shared<MoveInstruct>();
new_move->src_full = "%reg." + arg_regs[i];
new_move->dest_full = func->args_full_name[i];
new_move->ty = func->args[i];
entry_node->corresponding_block->actions.push_front(new_move);
entry_node->corresponding_block->actions.push_front(new_def);
missing_caller_saved_regs.erase(arg_regs[i]);
}
for (size_t i = 8; i < func->args_full_name.size(); i++) {
auto arg_load = std::make_shared<LoadSpilledArgs>();
arg_load->arg_id = i;
arg_load->var_full = func->args_full_name[i];
arg_load->ty = func->args[i];
entry_node->corresponding_block->actions.push_front(arg_load);
}
for (auto callee_saved_reg : callee_saved_regs) {
auto new_def = std::make_shared<ForceDef>();
new_def->var_full = "%reg." + callee_saved_reg;
new_def->ty = LLVMIRIntType(32);
auto new_move = std::make_shared<MoveInstruct>();
new_move->src_full = new_def->var_full;
new_move->dest_full = "%calleesave." + callee_saved_reg;
new_move->ty = LLVMIRIntType(32);
entry_node->corresponding_block->actions.push_front(new_move);
entry_node->corresponding_block->actions.push_front(new_def);
}
for (auto node : cfg.nodes) {
auto block = node->corresponding_block;
if (std::dynamic_pointer_cast<RETAction>(block->exit_action)) {
for (auto callee_saved_reg : callee_saved_regs) {
auto new_move = std::make_shared<MoveInstruct>();
new_move->src_full = "%calleesave." + callee_saved_reg;
new_move->dest_full = "%reg." + callee_saved_reg;
new_move->ty = LLVMIRIntType(32);
auto new_use = std::make_shared<ForceUse>();
new_use->var_full = "%reg." + callee_saved_reg;
block->actions.push_back(new_move);
block->actions.push_back(new_use);
}
if (!std::holds_alternative<LLVMVOIDType>(std::dynamic_pointer_cast<RETAction>(block->exit_action)->type)) {
auto new_move = std::make_shared<MoveInstruct>();
new_move->src_full = std::dynamic_pointer_cast<RETAction>(block->exit_action)->value;
new_move->dest_full = "%reg.x10";
new_move->ty = std::dynamic_pointer_cast<RETAction>(block->exit_action)->type;
if (new_move->src_full == "%reg.x10" && new_move->dest_full == "%reg.x10") throw std::runtime_error("error");
block->actions.push_back(new_move);
std::dynamic_pointer_cast<RETAction>(block->exit_action)->value = "%reg.x10";
}
}
}
// TODO: process caller side
for (auto node : cfg.nodes) {
auto block = node->corresponding_block;
for (auto it_act = block->actions.begin(); it_act != block->actions.end(); ++it_act) {
if (!std::dynamic_pointer_cast<CallItem>(*it_act)) continue;
auto it_next = it_act;
++it_next;
auto call_act = std::dynamic_pointer_cast<CallItem>(*it_act);
if (!std::holds_alternative<LLVMVOIDType>(call_act->return_type)) {
auto return_value_collect = std::make_shared<MoveInstruct>();
return_value_collect->ty = call_act->return_type;
return_value_collect->src_full = "%reg.x10";
return_value_collect->dest_full = call_act->result_full;
block->actions.insert(it_next, return_value_collect);
call_act->result_full = "%reg.x10";
}
std::unordered_set<std::string> caller_saved_regs_to_process;
for (auto reg : caller_saved_regs) {
caller_saved_regs_to_process.insert(reg);
missing_caller_saved_regs.erase(reg);
}
for (size_t i = 0; i < call_act->args_val_full.size() & i < 8; i++) {
auto new_move = std::make_shared<MoveInstruct>();
new_move->ty = call_act->args_ty[i];
new_move->src_full = call_act->args_val_full[i];
new_move->dest_full = "%reg." + arg_regs[i];
block->actions.insert(it_act, new_move);
call_act->args_val_full[i] = "%reg." + arg_regs[i];
caller_saved_regs_to_process.erase(arg_regs[i]);
}
if (call_act->args_val_full.size() > 8) {
for (size_t i = call_act->args_val_full.size() - 1; i >= 8; i--) {
auto new_store = std::make_shared<StoreSpilledArgs>();
new_store->arg_id = i;
new_store->var_full = call_act->args_val_full[i];
new_store->ty = call_act->args_ty[i];
block->actions.insert(it_act, new_store);
if (i == call_act->args_val_full.size() - 1) {
new_store->move_sp_down = call_act->args_val_full.size() - 8;
} else {
new_store->move_sp_down = 0;
}
}
call_act->move_sp_up = call_act->args_val_full.size() - 8;
call_act->args_val_full.resize(8);
call_act->args_ty.resize(8);
} else {
call_act->move_sp_up = 0;
}
for (auto reg : caller_saved_regs_to_process) {
auto new_def = std::make_shared<ForceDef>();
new_def->var_full = "%reg." + reg;
new_def->ty = LLVMIRIntType(32);
block->actions.insert(it_act, new_def);
}
for (auto reg : caller_saved_regs) {
auto new_use = std::make_shared<ForceUse>();
new_use->var_full = "%reg." + reg;
block->actions.insert(it_next, new_use);
}
it_act = it_next;
--it_act;
}
}
// avoid missing some caller saved regs
for (auto reg : missing_caller_saved_regs) {
auto new_def = std::make_shared<ForceDef>();
new_def->var_full = "%reg." + reg;
new_def->ty = LLVMIRIntType(32);
auto new_use = std::make_shared<ForceUse>();
new_use->var_full = "%reg." + reg;
entry_node->corresponding_block->actions.push_front(new_use);
entry_node->corresponding_block->actions.push_front(new_def);
}
}
void TranslateColorResult(std::shared_ptr<FunctionDefItem> func, CFGType &cfg, ConfGraph &confgraph) {
using namespace opt;
std::unordered_map<std::string, size_t> spilled_var_to_id;
auto &var_to_id = cfg.var_to_id;
auto ApplyColoringResult = [&](std::string &var) {
auto confnode = confgraph.id_to_node[var_to_id[var]];
confnode = ConfGraphNode::FindFather(confnode);
if (!confnode->is_binded_with_physical_reg) {
if (spilled_var_to_id.find(var) != spilled_var_to_id.end()) {
var = "#" + std::to_string(spilled_var_to_id[var]);
} else {
spilled_var_to_id[var] = func->spilled_vars++;
var = "#" + std::to_string(spilled_var_to_id[var]);
}
} else {
var = "$reg." + std::to_string(confnode->color);
}
};
func->spilled_vars = 0;
for (auto node : cfg.nodes) {
auto block = node->corresponding_block;
std::vector<size_t> cur_node_use;
std::vector<size_t> cur_node_def;
bool use_def_init = false;
for (auto act : block->actions) {
if (auto br_act = std::dynamic_pointer_cast<BRAction>(act)) {
if (var_to_id.find(br_act->cond) != var_to_id.end()) {
ApplyColoringResult(br_act->cond);
}
} else if (auto ret_act = std::dynamic_pointer_cast<RETAction>(act)) {
if (!std::holds_alternative<LLVMVOIDType>(ret_act->type) && var_to_id.find(ret_act->value) != var_to_id.end()) {
ApplyColoringResult(ret_act->value);
}
} else if (auto bin_act = std::dynamic_pointer_cast<BinaryOperationAction>(act)) {
if (var_to_id.find(bin_act->operand1_full) != var_to_id.end()) {
ApplyColoringResult(bin_act->operand1_full);
}
if (var_to_id.find(bin_act->operand2_full) != var_to_id.end()) {
ApplyColoringResult(bin_act->operand2_full);
}
if (var_to_id.find(bin_act->result_full) != var_to_id.end()) {
ApplyColoringResult(bin_act->result_full);
}
} else if (auto load_act = std::dynamic_pointer_cast<LoadAction>(act)) {
if (var_to_id.find(load_act->ptr_full) != var_to_id.end()) {
ApplyColoringResult(load_act->ptr_full);
}
if (var_to_id.find(load_act->result_full) != var_to_id.end()) {
ApplyColoringResult(load_act->result_full);
}
} else if (auto store_act = std::dynamic_pointer_cast<StoreAction>(act)) {
if (var_to_id.find(store_act->value_full) != var_to_id.end()) {
ApplyColoringResult(store_act->value_full);
}
if (var_to_id.find(store_act->ptr_full) != var_to_id.end()) {
ApplyColoringResult(store_act->ptr_full);
}
} else if (auto get_act = std::dynamic_pointer_cast<GetElementPtrAction>(act)) {
std::unordered_set<std::string> used_vars;
if (var_to_id.find(get_act->ptr_full) != var_to_id.end()) {
ApplyColoringResult(get_act->ptr_full);
}
for (auto &idx : get_act->indices) {
if (var_to_id.find(idx) != var_to_id.end()) {
ApplyColoringResult(idx);
}
}
if (var_to_id.find(get_act->result_full) != var_to_id.end()) {
ApplyColoringResult(get_act->result_full);
}
} else if (auto icmp_act = std::dynamic_pointer_cast<ICMPAction>(act)) {
if (var_to_id.find(icmp_act->operand1_full) != var_to_id.end()) {
ApplyColoringResult(icmp_act->operand1_full);
}
if (var_to_id.find(icmp_act->operand2_full) != var_to_id.end()) {
ApplyColoringResult(icmp_act->operand2_full);
}
if (var_to_id.find(icmp_act->result_full) != var_to_id.end()) {
ApplyColoringResult(icmp_act->result_full);
}
} else if (auto call_act = std::dynamic_pointer_cast<CallItem>(act)) {
for (auto &arg : call_act->args_val_full) {
if (var_to_id.find(arg) != var_to_id.end()) {
ApplyColoringResult(arg);
}
}
if (!std::holds_alternative<LLVMVOIDType>(call_act->return_type) &&
var_to_id.find(call_act->result_full) != var_to_id.end()) {
ApplyColoringResult(call_act->result_full);
}
} else if (auto select_act = std::dynamic_pointer_cast<SelectItem>(act)) {
if (var_to_id.find(select_act->cond_full) != var_to_id.end()) {
ApplyColoringResult(select_act->cond_full);
}
if (var_to_id.find(select_act->true_val_full) != var_to_id.end()) {
ApplyColoringResult(select_act->true_val_full);
}
if (var_to_id.find(select_act->false_val_full) != var_to_id.end()) {
ApplyColoringResult(select_act->false_val_full);
}
if (var_to_id.find(select_act->result_full) != var_to_id.end()) {
ApplyColoringResult(select_act->result_full);
}
} else if (auto move_act = std::dynamic_pointer_cast<MoveInstruct>(act)) {
if (VRegCheck(move_act->src_full) && var_to_id.find(move_act->src_full) != var_to_id.end()) {
ApplyColoringResult(move_act->src_full);
}
if (var_to_id.find(move_act->dest_full) != var_to_id.end()) {
ApplyColoringResult(move_act->dest_full);
}
} else if (auto force_def_act = std::dynamic_pointer_cast<ForceDef>(act)) {
if (var_to_id.find(force_def_act->var_full) != var_to_id.end()) {
ApplyColoringResult(force_def_act->var_full);
}
} else if (auto force_use_act = std::dynamic_pointer_cast<ForceUse>(act)) {
if (var_to_id.find(force_use_act->var_full) != var_to_id.end()) {
ApplyColoringResult(force_use_act->var_full);
}
} else if (auto load_spilled_args_act = std::dynamic_pointer_cast<LoadSpilledArgs>(act)) {
if (var_to_id.find(load_spilled_args_act->var_full) != var_to_id.end()) {
ApplyColoringResult(load_spilled_args_act->var_full);
}
} else if (auto store_spilled_args_act = std::dynamic_pointer_cast<StoreSpilledArgs>(act)) {
if (var_to_id.find(store_spilled_args_act->var_full) != var_to_id.end()) {
ApplyColoringResult(store_spilled_args_act->var_full);
}
} else if (auto alloca_act = std::dynamic_pointer_cast<AllocaAction>(act)) {
ApplyColoringResult(alloca_act->name_full);
}
}
{
auto act = block->exit_action;
if (auto br_act = std::dynamic_pointer_cast<BRAction>(act)) {
if (var_to_id.find(br_act->cond) != var_to_id.end()) {
ApplyColoringResult(br_act->cond);
}
} else if (auto ret_act = std::dynamic_pointer_cast<RETAction>(act)) {
if (!std::holds_alternative<LLVMVOIDType>(ret_act->type) && var_to_id.find(ret_act->value) != var_to_id.end()) {
ApplyColoringResult(ret_act->value);
}
}
}
for (auto act_it = block->actions.begin(); act_it != block->actions.end(); ++act_it) {
bool need_remove = false;
if (auto move_act = std::dynamic_pointer_cast<MoveInstruct>(*act_it)) {
if (move_act->src_full == move_act->dest_full) {
need_remove = true;
}
}
// else if (auto force_def_act = std::dynamic_pointer_cast<ForceDef>(*act_it)) {
// need_remove = true;
// } else if (auto force_use_act = std::dynamic_pointer_cast<ForceUse>(*act_it)) {
// need_remove = true;
// }
if (need_remove) {
auto it_next = act_it;
++it_next;
block->actions.erase(act_it);
act_it = it_next;
--act_it;
}
}
}
}
void PairMoveEliminate(std::shared_ptr<FunctionDefItem> func, CFGType &cfg, ConfGraph &confgraph) {
for (auto node : cfg.nodes) {
auto block = node->corresponding_block;
auto it = block->actions.begin();
while (it != block->actions.end()) {
while (it != block->actions.end() && !std::dynamic_pointer_cast<opt::MoveInstruct>(*it)) {
++it;
}
if (it == block->actions.end()) break;
std::unordered_map<std::string, std::list<std::shared_ptr<ActionItem>>::iterator> defined_by;
do {
auto cur_move = std::dynamic_pointer_cast<opt::MoveInstruct>(*it);
if (defined_by.find(cur_move->src_full) != defined_by.end() &&
std::dynamic_pointer_cast<opt::MoveInstruct>(*defined_by[cur_move->src_full])->src_full ==
cur_move->dest_full) {
auto it_next = it;
++it_next;
block->actions.erase(it);
it = it_next;
} else {
defined_by[cur_move->dest_full] = it;
++it;
}
} while (it != block->actions.end() && std::dynamic_pointer_cast<opt::MoveInstruct>(*it));
}
}
}
void RemoveCallingConventionKeeper(std::shared_ptr<FunctionDefItem> func, CFGType &cfg, ConfGraph &confgraph) {
for (auto node : cfg.nodes) {
auto block = node->corresponding_block;
std::vector<std::list<std::shared_ptr<ActionItem>>::iterator> act_to_move;
for (auto it = block->actions.begin(); it != block->actions.end(); ++it) {
if (std::dynamic_pointer_cast<opt::ForceDef>(*it) || std::dynamic_pointer_cast<opt::ForceUse>(*it)) {
act_to_move.push_back(it);
}
}
for (auto it : act_to_move) {
block->actions.erase(it);
}
}
}
void ConductRegAllocForFunction(std::shared_ptr<FunctionDefItem> func) {
std::cerr << "processing function " << func->func_name_raw << std::endl;
CFGType cfg;
ConfGraph confgraph;
cfg = BuildCFGForFunction(func);
EnforcePhysicalRegs(cfg);
// func->RecursivePrint(std::cerr);
do {
cfg.init();
cfg = BuildCFGForFunction(func);
LiveAnalysis(cfg);
confgraph.init();
confgraph = BuildConfGraph(cfg);
} while (ConductColoring(func, cfg, confgraph));
TranslateColorResult(func, cfg, confgraph);
RemoveCallingConventionKeeper(func, cfg, confgraph);
// func->RecursivePrint(std::cerr);
}
std::shared_ptr<ModuleItem> RegAlloc(std::shared_ptr<ModuleItem> src) {
auto res = src;
for (auto &func : res->function_defs) {
// func = std::make_shared<FunctionDefItem>(*func);
ConductRegAllocForFunction(func);
}
return res;
}