factor/vm/jit.cpp

155 lines
3.8 KiB
C++

#include "master.hpp"
namespace factor
{
/* Simple code generator used by:
- 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)
{
fixnum old_count = atomic::fetch_add(&parent->current_jit_count, 1);
FACTOR_ASSERT(old_count >= 0);
(void)old_count;
}
jit::~jit()
{
fixnum old_count = atomic::fetch_subtract(&parent->current_jit_count, 1);
FACTOR_ASSERT(old_count >= 1);
(void)old_count;
}
void jit::emit_relocation(cell relocation_template_)
{
data_root<byte_array> relocation_template(relocation_template_,parent);
cell capacity = array_capacity(relocation_template.untagged())
/ sizeof(relocation_entry);
relocation_entry *relocations = relocation_template->data<relocation_entry>();
for(cell i = 0; i < capacity; i++)
{
relocation_entry entry = relocations[i];
relocation_entry new_entry(entry.rel_type(), entry.rel_class(),
entry.rel_offset() + code.count);
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(array_nth(code_template.untagged(),0));
data_root<byte_array> insns(array_nth(code_template.untagged(),1),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());
}
/* Allocates memory */
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());
}
/* Allocates memory */
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());
}
/* Allocates memory */
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(cell frame_size)
{
/* Emit dummy GC info */
code.grow_bytes(alignment_for(code.count + 4,data_alignment));
u32 dummy_gc_info = 0;
code.append_bytes(&dummy_gc_info,sizeof(u32));
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(),
frame_size);
}
}