factor/vm/jit.cpp

135 lines
3.3 KiB
C++

#include "master.hpp"
namespace factor
{
/* Simple code generator used by:
- profiler (profiler.cpp),
- quotation compiler (quotations.cpp),
- megamorphic caches (dispatch.cpp),
- polymorphic inline caches (inline_cache.cpp) */
/* Allocates memory */
jit::jit(code_block_type type_, cell owner_, factor_vm *vm)
: type(type_),
owner(owner_,vm),
code(vm),
relocation(vm),
parameters(vm),
literals(vm),
computing_offset_p(false),
position(0),
offset(0),
parent(vm)
{}
void jit::emit_relocation(cell code_template_)
{
data_root<array> code_template(code_template_,parent);
cell capacity = array_capacity(code_template.untagged());
for(cell i = 1; i < capacity; i += 3)
{
relocation_class rel_class = (relocation_class)untag_fixnum(array_nth(code_template.untagged(),i));
relocation_type rel_type = (relocation_type)untag_fixnum(array_nth(code_template.untagged(),i + 1));
cell offset = array_nth(code_template.untagged(),i + 2);
relocation_entry new_entry(rel_type,rel_class,code.count + untag_fixnum(offset));
relocation.append_bytes(&new_entry,sizeof(relocation_entry));
}
}
/* Allocates memory */
void jit::emit(cell code_template_)
{
data_root<array> code_template(code_template_,parent);
emit_relocation(code_template.value());
data_root<byte_array> insns(array_nth(code_template.untagged(),0),parent);
if(computing_offset_p)
{
cell size = array_capacity(insns.untagged());
if(offset == 0)
{
position--;
computing_offset_p = false;
}
else if(offset < size)
{
position++;
computing_offset_p = false;
}
else
offset -= size;
}
code.append_byte_array(insns.value());
}
void jit::emit_with_literal(cell code_template_, cell argument_) {
data_root<array> code_template(code_template_,parent);
data_root<object> argument(argument_,parent);
literal(argument.value());
emit(code_template.value());
}
void jit::emit_with_parameter(cell code_template_, cell argument_) {
data_root<array> code_template(code_template_,parent);
data_root<object> argument(argument_,parent);
parameter(argument.value());
emit(code_template.value());
}
bool jit::emit_subprimitive(cell word_, bool tail_call_p, bool stack_frame_p)
{
data_root<word> word(word_,parent);
data_root<array> code_template(word->subprimitive,parent);
parameters.append(untag<array>(array_nth(code_template.untagged(),0)));
literals.append(untag<array>(array_nth(code_template.untagged(),1)));
emit(array_nth(code_template.untagged(),2));
if(array_capacity(code_template.untagged()) == 5)
{
if(tail_call_p)
{
if(stack_frame_p) emit(parent->special_objects[JIT_EPILOG]);
emit(array_nth(code_template.untagged(),4));
return true;
}
else
emit(array_nth(code_template.untagged(),3));
}
return false;
}
/* Facility to convert compiled code offsets to quotation offsets.
Call jit_compute_offset() with the compiled code offset, then emit
code, and at the end jit->position is the quotation position. */
void jit::compute_position(cell offset_)
{
computing_offset_p = true;
position = 0;
offset = offset_;
}
/* Allocates memory */
code_block *jit::to_code_block()
{
code.trim();
relocation.trim();
parameters.trim();
literals.trim();
return parent->add_code_block(
type,
code.elements.value(),
false_object, /* no labels */
owner.value(),
relocation.elements.value(),
parameters.elements.value(),
literals.elements.value());
}
}