xo-tokenizer2/src/jit/Jit.cpp

295 lines
10 KiB
C++

/* @file Jit.cpp */
#include "Jit.hpp"
namespace xo {
using xo::ast::exprtype;
using xo::ast::Expression;
using xo::ast::ConstantInterface;
using xo::ast::PrimitiveInterface;
using xo::ast::Lambda;
using xo::ast::Variable;
using xo::ast::Apply;
using xo::reflect::TypeDescr;
using std::cerr;
using std::endl;
namespace jit {
Jit::Jit()
: llvm_cx_{std::make_unique<llvm::LLVMContext>()},
llvm_ir_builder_{std::make_unique<llvm::IRBuilder<>>(*llvm_cx_)},
llvm_module_{std::make_unique<llvm::Module>("xojit", *llvm_cx_)}
{}
llvm::Value *
Jit::codegen_constant(ref::brw<ConstantInterface> expr)
{
TypeDescr td = expr->value_td();
if (td->is_native<double>()) {
return llvm::ConstantFP::get(*llvm_cx_,
llvm::APFloat(*(expr->value_tp().recover_native<double>())));
} else if (td->is_native<float>()) {
return llvm::ConstantFP::get(*llvm_cx_,
llvm::APFloat(*(expr->value_tp().recover_native<float>())));
}
return nullptr;
}
llvm::Function *
Jit::codegen_primitive(ref::brw<PrimitiveInterface> expr)
{
/** note: documentation (such as it is) for llvm::Function here:
*
* https://llvm.org/doxygen/classllvm_1_1Function.html
**/
auto * fn = llvm_module_->getFunction(expr->name());
if (fn) {
/** function with this name already known to llvm module;
* use that definition
*
* TODO: verify that signatures match!
**/
return fn;
}
/** establish prototype for this function **/
// PLACEHOLDER
// just make prototype for function :: double -> double
TypeDescr fn_td = expr->value_td();
int n_fn_arg = fn_td->n_fn_arg();
std::vector<llvm::Type *> llvm_argtype_v(n_fn_arg);
/** check function args are all doubles **/
for (int i = 0; i < n_fn_arg; ++i) {
TypeDescr arg_td = fn_td->fn_arg(i);
if (arg_td->is_native<double>()) {
llvm_argtype_v.push_back(llvm::Type::getDoubleTy(*llvm_cx_));
// TODO: extend with other native types here...
} else {
cerr << "Jit::codegen_primitive: error: primitive f with arg i of type T where double expected"
<< xtag("f", expr->name())
<< xtag("i", i)
<< xtag("T", arg_td->short_name())
<< endl;
return nullptr;
}
}
//std::vector<llvm::Type *> double_v(n_fn_arg, llvm::Type::getDoubleTy(*llvm_cx_));
TypeDescr retval_td = fn_td->fn_retval();
llvm::Type * llvm_retval = nullptr;
if (retval_td->is_native<double>()) {
llvm_retval = llvm::Type::getDoubleTy(*llvm_cx_);
} else {
cerr << "Jit::codegen_primitive: error: primitive f returning T where double expected"
<< xtag("f", expr->name())
<< xtag("T", retval_td->short_name())
<< endl;
return nullptr;
}
auto * llvm_fn_type = llvm::FunctionType::get(llvm_retval,
llvm_argtype_v,
false /*!varargs*/);
fn = llvm::Function::Create(llvm_fn_type,
llvm::Function::ExternalLinkage,
expr->name(),
llvm_module_.get());
// set names for arguments (for diagonostics?). Money-see-kaleidoscope-monkey-do here
#ifdef NOT_USING
for (auto & arg : fn->args())
arg.setName(formalnameofthisarg);
#endif
return fn;
} /*codegen_primitive*/
llvm::Value *
Jit::codegen_apply(ref::brw<Apply> apply)
{
using std::cerr;
using std::endl;
/* editorial:
*
* to handle (computed functions) properly,
* we will need a runtime representation for a 'primitive function pointer'
*
* For now, finesse by only handling PrimitiveInterface in function-callee position
*/
if (apply->fn()->extype() == exprtype::primitive) {
auto pm = PrimitiveInterface::from(apply->fn());
auto * fn = this->codegen_primitive(pm);
#ifdef NOT_USING_DEBUG
cerr << "Jit::codegen_apply: fn:" << endl;
fn->print(llvm::errs());
cerr << endl;
#endif
if (fn->arg_size() != apply->argv().size()) {
cerr << "Jit::codegen_apply: error: callee f expecting n1 args where n2 supplied"
<< xtag("f", pm->name())
<< xtag("n1", pm->n_arg())
<< xtag("n2", apply->argv().size())
<< endl;
return nullptr;
}
std::vector<llvm::Value *> args;
args.reserve(apply->argv().size());
for (const auto & arg_expr : apply->argv()) {
auto * arg = this->codegen(arg_expr);
#ifdef NOT_USING_DEBUG
cerr << "Jit::codegen_apply: arg:" << endl;
arg->print(llvm::errs());
cerr << endl;
#endif
args.push_back(arg);
}
return llvm_ir_builder_->CreateCall(fn, args, "calltmp");
} else {
cerr << "Jit::codegen_apply: error: only allowing call to known primitives at present" << endl;
return nullptr;
}
} /*codegen_apply*/
llvm::Function *
Jit::codegen_lambda(ref::brw<Lambda> lambda)
{
/* reminder! this is the *expression*, not the *closure* */
global_env_[lambda->name()] = lambda.get();
/* do we already know a function with this name? */
auto * fn = llvm_module_->getFunction(lambda->name());
if (fn) {
/** function with this name already defined?? **/
return nullptr;
}
/* establish prototype for this function */
// PLACEHOLDER
// just make prototype for function :: double -> double
std::vector<llvm::Type *> double_v(1, llvm::Type::getDoubleTy(*llvm_cx_));
auto * llvm_fn_type = llvm::FunctionType::get(llvm::Type::getDoubleTy(*llvm_cx_),
double_v,
false /*!varargs*/);
/* create (initially empty) function */
fn = llvm::Function::Create(llvm_fn_type,
llvm::Function::ExternalLinkage,
lambda->name(),
llvm_module_.get());
/* also capture argument names */
int i = 0;
for (auto & arg : fn->args())
arg.setName(lambda->argv().at(i));
/* generate function body */
auto block = llvm::BasicBlock::Create(*llvm_cx_, "entry", fn);
llvm_ir_builder_->SetInsertPoint(block);
/* formal parameters need to appear in named_value_map_ */
nested_env_.clear();
for (auto & arg : fn->args())
nested_env_[std::string(arg.getName())] = &arg;
llvm::Value * retval = this->codegen(lambda->body());
if (retval) {
/* completes the function.. */
llvm_ir_builder_->CreateRet(retval);
/* validate! always validate! */
llvm::verifyFunction(*fn);
/* optimize! */
// thefpm->run(*fn, *thefam);
return fn;
}
/* oops, something went wrong */
fn->eraseFromParent();
return nullptr;
} /*codegen_lambda*/
llvm::Value *
Jit::codegen_variable(ref::brw<Variable> var)
{
auto ix = nested_env_.find(var->name());
if (ix == nested_env_.end()) {
cerr << "Jit::codegen_variable: no binding for variable x"
<< xtag("x", var->name())
<< endl;
}
return ix->second;
} /*codegen_variable*/
llvm::Value *
Jit::codegen(ref::brw<Expression> expr)
{
switch(expr->extype()) {
case exprtype::constant:
return this->codegen_constant(ConstantInterface::from(expr));
case exprtype::primitive:
return this->codegen_primitive(PrimitiveInterface::from(expr));
case exprtype::apply:
return this->codegen_apply(Apply::from(expr));
case exprtype::lambda:
return this->codegen_lambda(Lambda::from(expr));
case exprtype::variable:
return this->codegen_variable(Variable::from(expr));
case exprtype::invalid:
case exprtype::n_expr:
return nullptr;
break;
}
cerr << "Jit::codegen: error: no handler for expression of type T"
<< xtag("T", expr->extype())
<< endl;
return nullptr;
} /*codegen*/
void
Jit::display(std::ostream & os) const {
os << "<Jit>";
}
std::string
Jit::display_string() const {
return tostr(*this);
}
} /*namespace jit*/
} /*namespace xo*/
/* end Jit.cpp */