Files
ivy/lang/codegen/unit.c
Max Wash 7483b32c25 lang: codegen: redesign variable definition/resolution system to support capturing
the codegen scope system has been removed. instead, each generator state in the stack,
from the current state backwards, is informed when a variable is defined, resolved, or
captured.

when a variable is defined, the state stack is traversed back-to-front (current generator
first). each state has a chance to record the variable definition. once one state has
signalled that it has recorded the variable definition, the traversal ends.

when a variable is resolved, the state stack is traversed back-to-front (current generator
first). each state is asked whether or not it recognises the variable identifier being resolved.
if a state has the variable in question defined, it returns information about the variable
definition, and the traversal stops.

once a variable has been resolved, the state stack is traversed front-to-back (current generator
last), starting from the generator /after/ the one that provided the variable definition. each
generator in the iteration is given the chance to adjust the variable information, or generate
IR in response to the variable being accessed. this is used to implement variable capture,
where the state of a variable in the enclosing context is captured for later use.
2025-04-22 15:23:42 +01:00

208 lines
5.6 KiB
C

#include "codegen.h"
#include "var-map.h"
#include <mie/block.h>
#include <mie/func.h>
#include <mie/module.h>
struct unit_codegen_state {
struct code_generator_state s_base;
struct code_generator_scope *s_scope;
/* function for top-level statements */
// struct mie_block *s_immediate_alloca;
struct mie_func *s_immediate;
struct codegen_var_map s_vars;
};
static enum ivy_status switch_to_immediate_func(
struct ivy_codegen *gen, struct unit_codegen_state *unit)
{
if (!unit->s_immediate) {
struct mie_type *ret_type
= mie_ctx_get_type(gen->c_ctx, MIE_TYPE_VOID);
unit->s_immediate = mie_func_create(MIE_FUNC_STATIC, ret_type);
if (!unit->s_immediate) {
return IVY_ERR_NO_MEMORY;
}
mie_module_add_function(
gen->c_module, unit->s_immediate, "init");
}
struct mie_block *block = mie_func_get_last_block(unit->s_immediate);
if (!block) {
#if 0
unit->s_immediate_alloca
= mie_func_create_block(unit->s_immediate, "alloca");
mie_func_insert_block(
unit->s_immediate, unit->s_immediate_alloca, NULL);
#endif
block = mie_func_create_block(unit->s_immediate, "entry");
mie_func_insert_block(unit->s_immediate, block, NULL);
}
if (mie_block_is_terminated(block)) {
block = mie_func_create_block(unit->s_immediate, NULL);
mie_func_insert_block(unit->s_immediate, block, NULL);
}
mie_builder_set_insert_point(gen->c_builder, block);
return IVY_OK;
}
#if 0
static enum ivy_status switch_to_immediate_alloca(
struct ivy_codegen *gen, struct unit_codegen_state *unit)
{
enum ivy_status status = switch_to_immediate_func(gen, unit);
if (status != IVY_OK) {
return status;
}
mie_builder_set_insert_point(gen->c_builder, unit->s_immediate_alloca);
return IVY_OK;
}
#endif
static struct code_generator_result gen_expr(
struct ivy_codegen *gen, struct code_generator_state *state,
struct ivy_ast_node *node, size_t depth)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
struct mie_builder *builder = gen->c_builder;
struct mie_func *current = mie_builder_get_current_func(builder);
enum ivy_status status = IVY_OK;
if (!current || current != unit->s_immediate) {
status = switch_to_immediate_func(gen, unit);
}
if (status != IVY_OK) {
return CODEGEN_RESULT_ERR(status);
}
codegen_push_generator(
gen, CODE_GENERATOR_EXPR, CODEGEN_F_IGNORE_RESULT, NULL);
return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
}
static struct code_generator_result gen_var_declaration(
struct ivy_codegen *gen, struct code_generator_state *state,
struct ivy_ast_node *node, size_t depth)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
struct mie_builder *builder = gen->c_builder;
struct mie_func *current = mie_builder_get_current_func(builder);
enum ivy_status status = IVY_OK;
if (!current || current != unit->s_immediate) {
status = switch_to_immediate_func(gen, unit);
}
if (status != IVY_OK) {
return CODEGEN_RESULT_ERR(status);
}
codegen_push_generator(gen, CODE_GENERATOR_VAR, 0, NULL);
return CODEGEN_RESULT_OK(CODEGEN_R_REPEAT_NODE);
}
#if 0
static struct code_generator_result gen_var_declaration(
struct ivy_codegen *gen, struct code_generator_state *state,
struct ivy_ast_node *node)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
struct mie_builder *builder = gen->c_builder;
struct mie_block *current_block
= mie_builder_get_current_block(gen->c_builder);
enum ivy_status status = IVY_OK;
if (!current_block || current_block != unit->s_immediate_alloca) {
status = switch_to_immediate_alloca(gen, unit);
}
struct codegen_value *value = codegen_pop_value(gen);
struct codegen_value *dest = codegen_pop_value(gen);
if (!dest) {
return CODEGEN_RESULT_ERR(IVY_ERR_BAD_SYNTAX);
}
struct mie_type *id_type = mie_ctx_get_type(gen->c_ctx, MIE_TYPE_ID);
struct mie_value *var_ptr = mie_builder_alloca(builder, id_type, NULL);
if (value) {
mie_builder_store(builder, value->v_value, var_ptr);
}
code_generator_scope_put_variable(
unit->s_scope, (struct ivy_ast_ident_node *)dest->v_node, var_ptr);
return CODEGEN_RESULT_OK(0);
}
#endif
static enum ivy_status state_init(
struct ivy_codegen *gen, struct code_generator_state *state,
uintptr_t argv, void *argp)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
codegen_var_map_init(&unit->s_vars);
return IVY_OK;
}
static enum ivy_status state_fini(
struct ivy_codegen *gen, struct code_generator_state *state,
struct mie_value **result)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
codegen_var_map_fini(&unit->s_vars);
return IVY_OK;
}
static enum ivy_status define_var(
struct ivy_codegen *gen, struct code_generator_state *state,
const char *ident, const struct codegen_var *var)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
return codegen_var_map_put(&unit->s_vars, ident, var);
}
static enum ivy_status resolve_var(
struct ivy_codegen *gen, struct code_generator_state *state,
const char *ident, struct codegen_var *var)
{
struct unit_codegen_state *unit = (struct unit_codegen_state *)state;
struct codegen_var *result = NULL;
enum ivy_status status
= codegen_var_map_get(&unit->s_vars, ident, &result);
if (status != IVY_OK) {
return status;
}
memcpy(var, result, sizeof *var);
return IVY_OK;
}
struct code_generator unit_generator = {
.g_type = CODE_GENERATOR_UNIT,
.g_state_size = sizeof(struct unit_codegen_state),
.g_state_init = state_init,
.g_state_fini = state_fini,
.g_node_generators = {
NODE_CODEGEN(VAR, gen_var_declaration),
},
.g_expr_generator = gen_expr,
.g_define_var = define_var,
.g_resolve_var = resolve_var,
};