ast.cc

/******************************************************************************
  Copyright (c) 1992, 1995, 1996 Xerox Corporation.  All rights reserved.
  Portions of this code were written by Stephen White, aka ghond.
  Use and copying of this software and preparation of derivative works based
  upon this software are permitted.  Any distribution of this software or
  derivative works must comply with all applicable United States export
  control laws.  This software is made available AS IS, and Xerox Corporation
  makes no warranty about the software, its performance or its conformity to
  any specification.  Any person obtaining a copy of this software is requested
  to send their name and post office or electronic mail address to:
    Pavel Curtis
    Xerox PARC
    3333 Coyote Hill Rd.
    Palo Alto, CA 94304
    Pavel@Xerox.Com
 *****************************************************************************/

#include "my-string.h"

#include "ast.h"
#include "config.h"
#include "list.h"
#include "log.h"
#include "program.h"
#include "structures.h"
#include "sym_table.h"
#include "storage.h"
#include "utils.h"

struct entry {
    void *ptr;
    Memory_Type type;
};

static int pool_size, next_pool_slot;
static struct entry *pool;

void
begin_code_allocation()
{
    pool_size = 10;
    next_pool_slot = 0;
    pool = (struct entry *)mymalloc(pool_size * sizeof(struct entry), M_AST_POOL);
}

void
end_code_allocation(int aborted)
{
    if (aborted) {
	int i;

	for (i = 0; i < next_pool_slot; i++) {
	    if (pool[i].ptr != 0)
		myfree(pool[i].ptr, pool[i].type);
	}
    }
    myfree(pool, M_AST_POOL);
}

static void *
allocate(int size, Memory_Type type)
{
    if (next_pool_slot >= pool_size) {	/* enlarge the pool */
	struct entry *new_pool;
	int i;

	pool_size *= 2;
	new_pool = (struct entry *)mymalloc(pool_size * sizeof(struct entry), M_AST_POOL);
	for (i = 0; i < next_pool_slot; i++) {
	    new_pool[i] = pool[i];
	}
	myfree(pool, M_AST_POOL);
	pool = new_pool;
    }
    pool[next_pool_slot].type = type;
    return pool[next_pool_slot++].ptr = mymalloc(size, type);
}

static void
deallocate(void *ptr)
{
    int i;

    for (i = 0; i < next_pool_slot; i++) {
	if (ptr == pool[i].ptr) {
	    myfree(ptr, pool[i].type);
	    pool[i].ptr = 0;
	    return;
	}
    }

    errlog("DEALLOCATE: Unknown pointer deallocated\n");
}

char *
alloc_string(const char *buffer)
{
    char *string = (char *)allocate(strlen(buffer) + 1, M_STRING);

    strcpy(string, buffer);
    return string;
}

void
dealloc_string(char *str)
{
    deallocate(str);
}

double *
alloc_float(double value)
{
    double *d = (double *)allocate(sizeof(double), M_FLOAT);

    *d = value;
    return d;
}

void
dealloc_node(void *node)
{
    deallocate(node);
}

Stmt *
alloc_stmt(enum Stmt_Kind kind)
{
    Stmt *result = (Stmt *)allocate(sizeof(Stmt), M_AST);

    result->kind = kind;
    result->next = 0;
    return result;
}

Cond_Arm *
alloc_cond_arm(Expr * condition, Stmt * stmt)
{
    Cond_Arm *result = (Cond_Arm *)allocate(sizeof(Cond_Arm), M_AST);

    result->condition = condition;
    result->stmt = stmt;
    result->next = 0;
    return result;
}

Except_Arm *
alloc_except(int id, Arg_List * codes, Stmt * stmt)
{
    Except_Arm *result = (Except_Arm *)allocate(sizeof(Except_Arm), M_AST);

    result->id = id;
    result->codes = codes;
    result->stmt = stmt;
    result->label = 0;
    result->next = 0;
    return result;
}

Expr *
alloc_expr(enum Expr_Kind kind)
{
    Expr *result = (Expr *)allocate(sizeof(Expr), M_AST);

    result->kind = kind;
    return result;
}

Expr *
alloc_var(var_type type)
{
    Expr *result = (Expr *)alloc_expr(EXPR_VAR);

    result->e.var.type = type;
    return result;
}

Expr *
alloc_binary(enum Expr_Kind kind, Expr * lhs, Expr * rhs)
{
    Expr *result = (Expr *)alloc_expr(kind);

    result->e.bin.lhs = lhs;
    result->e.bin.rhs = rhs;
    return result;
}

Expr *
alloc_verb(Expr * obj, Expr * verb, Arg_List * args)
{
    Expr *result = (Expr *)alloc_expr(EXPR_VERB);

    result->e.verb.obj = obj;
    result->e.verb.verb = verb;
    result->e.verb.args = args;
    return result;
}

Map_List *
alloc_map_list(Expr * key, Expr * value)
{
    Map_List *result = (Map_List *)allocate(sizeof(Map_List), M_AST);

    result->key = key;
    result->value = value;
    result->next = 0;
    return result;
}

Arg_List *
alloc_arg_list(enum Arg_Kind kind, Expr * expr)
{
    Arg_List *result = (Arg_List *)allocate(sizeof(Arg_List), M_AST);

    result->kind = kind;
    result->expr = expr;
    result->next = 0;
    return result;
}

Scatter *
alloc_scatter(enum Scatter_Kind kind, int id, Expr * expr)
{
    Scatter *sc = (Scatter *)allocate(sizeof(Scatter), M_AST);

    sc->kind = kind;
    sc->id = id;
    sc->expr = expr;
    sc->next = 0;
    sc->label = sc->next_label = 0;

    return sc;
}

static void free_expr(Expr *);

static void
free_map_list(Map_List * map)
{
    Map_List *m, *next_m;

    for (m = map; m; m = next_m) {
	next_m = m->next;
	free_expr(m->key);
	free_expr(m->value);
	myfree(m, M_AST);
    }
}

static void
free_arg_list(Arg_List * args)
{
    Arg_List *arg, *next_arg;

    for (arg = args; arg; arg = next_arg) {
	next_arg = arg->next;
	free_expr(arg->expr);
	myfree(arg, M_AST);
    }
}

static void
free_scatter(Scatter * sc)
{
    Scatter *next_sc;

    for (; sc; sc = next_sc) {
	next_sc = sc->next;
	if (sc->expr)
	    free_expr(sc->expr);
	myfree(sc, M_AST);
    }
}

static void
free_expr(Expr * expr)
{
    switch (expr->kind) {

    case EXPR_VAR:
	free_var(expr->e.var);
	break;

    case EXPR_ID:
    case EXPR_FIRST:
    case EXPR_LAST:
	/* Do nothing. */
	break;

    case EXPR_PROP:
    case EXPR_INDEX:
    case EXPR_PLUS:
    case EXPR_MINUS:
    case EXPR_TIMES:
    case EXPR_DIVIDE:
    case EXPR_MOD:
    case EXPR_AND:
    case EXPR_OR:
    case EXPR_EQ:
    case EXPR_NE:
    case EXPR_LT:
    case EXPR_LE:
    case EXPR_GT:
    case EXPR_GE:
    case EXPR_IN:
    case EXPR_ASGN:
    case EXPR_EXP:
    case EXPR_BITOR:
    case EXPR_BITAND:
    case EXPR_BITXOR:
    case EXPR_BITSHL:
    case EXPR_BITSHR:
	free_expr(expr->e.bin.lhs);
	free_expr(expr->e.bin.rhs);
	break;

    case EXPR_COND:
	free_expr(expr->e.cond.condition);
	free_expr(expr->e.cond.consequent);
	free_expr(expr->e.cond.alternate);
	break;

    case EXPR_VERB:
	free_expr(expr->e.verb.obj);
	free_expr(expr->e.verb.verb);
	free_arg_list(expr->e.verb.args);
	break;

    case EXPR_RANGE:
	free_expr(expr->e.range.base);
	free_expr(expr->e.range.from);
	free_expr(expr->e.range.to);
	break;

    case EXPR_CALL:
	free_arg_list(expr->e.call.args);
	break;

    case EXPR_NEGATE:
    case EXPR_NOT:
    case EXPR_COMPLEMENT:
	free_expr(expr->e.expr);
	break;

    case EXPR_MAP:
        free_map_list(expr->e.map);
        break;

    case EXPR_LIST:
	free_arg_list(expr->e.list);
	break;

    case EXPR_CATCH:
	free_expr(expr->e._catch._try);
	free_arg_list(expr->e._catch.codes);
	if (expr->e._catch.except)
	    free_expr(expr->e._catch.except);
	break;

    case EXPR_SCATTER:
	free_scatter(expr->e.scatter);
	break;

    default:
	errlog("FREE_EXPR: Unknown Expr_Kind: %d\n", expr->kind);
	break;
    }

    myfree(expr, M_AST);
}

void
free_stmt(Stmt * stmt)
{
    Stmt *next_stmt;
    Cond_Arm *arm, *next_arm;
    Except_Arm *except, *next_e;

    for (; stmt; stmt = next_stmt) {
	next_stmt = stmt->next;

	switch (stmt->kind) {

	case STMT_COND:
	    for (arm = stmt->s.cond.arms; arm; arm = next_arm) {
		next_arm = arm->next;
		free_expr(arm->condition);
		free_stmt(arm->stmt);
		myfree(arm, M_AST);
	    }
	    if (stmt->s.cond.otherwise)
		free_stmt(stmt->s.cond.otherwise);
	    break;

	case STMT_LIST:
	    free_expr(stmt->s.list.expr);
	    free_stmt(stmt->s.list.body);
	    break;

	case STMT_RANGE:
	    free_expr(stmt->s.range.from);
	    free_expr(stmt->s.range.to);
	    free_stmt(stmt->s.range.body);
	    break;

	case STMT_WHILE:
	    free_expr(stmt->s.loop.condition);
	    free_stmt(stmt->s.loop.body);
	    break;

	case STMT_FORK:
	    free_expr(stmt->s.fork.time);
	    free_stmt(stmt->s.fork.body);
	    break;

	case STMT_EXPR:
	case STMT_RETURN:
	    if (stmt->s.expr)
		free_expr(stmt->s.expr);
	    break;

	case STMT_TRY_EXCEPT:
	    free_stmt(stmt->s._catch.body);
	    for (except = stmt->s._catch.excepts; except; except = next_e) {
		next_e = except->next;
		free_arg_list(except->codes);
		free_stmt(except->stmt);
		myfree(except, M_AST);
	    }
	    break;

	case STMT_TRY_FINALLY:
	    free_stmt(stmt->s.finally.body);
	    free_stmt(stmt->s.finally.handler);
	    break;

	case STMT_BREAK:
	case STMT_CONTINUE:
	    break;		/* Nothing extra to free */

	default:
	    errlog("FREE_STMT: unknown Stmt_Kind: %d\n", stmt->kind);
	    break;
	}

	myfree(stmt, M_AST);
    }
}