blob: e5a9444597acb4edc32d73fe47c92eba1abcec65 [file] [log] [blame]
/* -*- mode:c -*- */
#include "compiler.h"
#include "lib/std.h"
#include "plat/plat.h"
#include <dasm_proto.h>
#include <dasm_x86.h>
#define value_size sizeof(value_t)
|.arch x86;
|.macro setup, nvars;
| push ebp;
| mov ebp, esp;
| sub esp, (value_size * nvars);
|.endmacro;
|.macro cleanup;
| mov esp, ebp;
| pop ebp;
| ret;
|.endmacro;
dasm_State *d;
unsigned int npc = 8;
struct function *find_function(struct environment *env, char *name)
{
struct function *f = env->first;
while (strcmp(f->name, name) != 0)
{
if (f->prev)
f = f->prev;
else
return NULL;
}
return f;
}
void compile_tl(value_t val, struct environment *env)
{
if (!listp(val))
err("Top level must be a list");
value_t form = car(val);
value_t args = cdr(val);
if (symstreq(form, "defun"))
{
dasm_State *d;
dasm_State **Dst = &d;
|.section code;
dasm_init(&d, DASM_MAXSECTION);
|.globals lbl_;
void *labels[lbl__MAX];
dasm_setupglobal(&d, labels, lbl__MAX);
|.actionlist lisp_actions;
dasm_setup(&d, lisp_actions);
dasm_growpc(&d, npc);
struct local local;
local.first = NULL;
local.num_vars = 0;
// Generate code
| setup 0;
value_t name = car(args);
args = cdr(args);
value_t arglist = car(args);
value_t body = cdr(args);
if ((name & HEAP_MASK) != SYMBOL_TAG)
err("function name must be a symbol");
for (; !nilp(body); body = cdr(body))
{
compile_expression(env, &local, car(body), Dst);
}
| cleanup;
add_function(env, (char *)(name ^ SYMBOL_TAG), link(Dst),
length(arglist));
dasm_free(&d);
}
}
struct environment compile_all(struct istream *is)
{
value_t val;
struct environment env;
env.first = NULL;
load_std(&env);
while (read1(is, &val))
{
compile_tl(val, &env);
}
return env;
}
int nextpc(struct local *local, dasm_State **Dst)
{
int n = local->nextpc++;
if (n > local->npc)
{
local->npc += 16;
dasm_growpc(Dst, local->npc);
}
return n;
}
void compile_expression(struct environment *env, struct local *local,
value_t val, dasm_State **Dst)
{
if (symstreq(val, "nil"))
{
| mov eax, (nil);
}
else if (integerp(val) || stringp(val) || symbolp(val))
{
| mov eax, val;
}
else if (listp(val))
{
value_t fsym = car(val);
value_t args = cdr(val);
int nargs = length(args);
if (!symbolp(fsym))
{
err("function name must be a symbol");
}
if (symstreq(fsym, "if"))
{
if (nargs < 2 || nargs > 3)
err("Must give at least 2 arguments to if");
compile_expression(env, local, car(args), Dst);
int false_label = nextpc(local, Dst),
after_label = nextpc(local, Dst);
// result is in eax
| cmp eax, (nil);
| je =>false_label;
compile_expression(env, local, elt(args, 1), Dst);
|=>false_label:
if (nargs == 3)
compile_expression(env, local, elt(args, 2), Dst);
|=>after_label:
}
else
{
struct function *func =
find_function(env, (char *)(fsym ^ SYMBOL_TAG));
if (nargs != func->nargs)
err("wrong number of args");
for (int i = length(args) - 1; i >= 0; i--)
{
compile_expression(env, local, elt(args, i), Dst);
| push eax;
}
| mov ebx, (func->code_addr);
| call ebx;
| add esp, (nargs * 4);
// result in eax
}
}
}
void compile_expr_to_func(struct environment *env, char *name, value_t val,
dasm_State **Dst)
{
| setup 0;
struct local local;
compile_expression(env, &local, val, Dst);
| cleanup;
add_function(env, name, link(Dst), 0);
}