/* Parse and emit initializer code for target variable in statements such as
* int b[] = {0, 1, 2, 3}. Generate a series of assignment operations on
* references to target variable.
*/
static struct block *initializer(struct block *block, struct var target)
{
assert(target.kind == DIRECT);
/* Do not care about cv-qualifiers here. */
target.type = unwrapped(target.type);
if (peek().token == '{') {
block = object_initializer(block, target);
} else {
block = assignment_expression(block);
if (!target.symbol->depth && block->expr.kind != IMMEDIATE) {
error("Initializer must be computable at load time.");
exit(1);
}
if (target.kind == DIRECT && !target.type->size) {
assert(!target.offset);
assert(is_string(block->expr));
assert(is_array(block->expr.type));
/* Complete type based on string literal. Evaluation does not have
* the required context to do this logic. */
((struct symbol *) target.symbol)->type.size =
block->expr.type->size;
target.type = block->expr.type;
}
eval_assign(block, target, block->expr);
}
return block;
}
struct block *assignment_expression(struct block *block)
{
struct var target;
block = conditional_expression(block);
target = block->expr;
switch (peek().token) {
case '=':
consume('=');
block = assignment_expression(block);
break;
case MUL_ASSIGN:
consume(MUL_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_MUL, target, block->expr);
break;
case DIV_ASSIGN:
consume(DIV_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_DIV, target, block->expr);
break;
case MOD_ASSIGN:
consume(MOD_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_MOD, target, block->expr);
break;
case PLUS_ASSIGN:
consume(PLUS_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_ADD, target, block->expr);
break;
case MINUS_ASSIGN:
consume(MINUS_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_SUB, target, block->expr);
break;
case AND_ASSIGN:
consume(AND_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_AND, target, block->expr);
break;
case OR_ASSIGN:
consume(OR_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_OR, target, block->expr);
break;
case XOR_ASSIGN:
consume(XOR_ASSIGN);
block = assignment_expression(block);
block->expr = eval_expr(block, IR_OP_XOR, target, block->expr);
break;
default:
return block;
}
block->expr = eval_assign(block, target, block->expr);
return block;
}
/**
Evaluate a function call
*/
value_t eval_call(
clos_t* callee,
array_t* arg_exprs,
clos_t* caller,
value_t* caller_locals
)
{
ast_fun_t* fptr = callee->fun;
assert (fptr != NULL);
if (arg_exprs->len != fptr->param_decls->len)
{
printf("argument count mismatch\n");
exit(-1);
}
// Allocate space for the local variables
value_t* callee_locals = alloca(
sizeof(value_t) * fptr->local_decls->len
);
// Allocate mutable cells for the escaping variables
for (size_t i = 0; i < fptr->esc_locals->len; ++i)
{
ast_decl_t* decl = array_get(fptr->esc_locals, i).word.decl;
assert (decl->esc);
assert (decl->idx < fptr->local_decls->len);
callee_locals[decl->idx] = value_from_obj((heapptr_t)cell_alloc());
}
// Evaluate the argument values
for (size_t i = 0; i < arg_exprs->len; ++i)
{
//printf("evaluating arg %ld\n", i);
heapptr_t param_decl = array_get_ptr(fptr->param_decls, i);
// Evaluate the parameter value
value_t arg_val = eval_expr(
array_get_ptr(arg_exprs, i),
caller,
caller_locals
);
// Assign the value to the parameter
eval_assign(
param_decl,
arg_val,
callee,
callee_locals
);
}
// Evaluate the unit function body in the local frame
return eval_expr(fptr->body_expr, callee, callee_locals);
}
static struct block *unary_expression(struct block *block)
{
struct var value;
switch (peek().token) {
case '&':
consume('&');
block = cast_expression(block);
block->expr = eval_addr(block, block->expr);
break;
case '*':
consume('*');
block = cast_expression(block);
block->expr = eval_deref(block, block->expr);
break;
case '!':
consume('!');
block = cast_expression(block);
block->expr = eval_expr(block, IR_OP_EQ, var_int(0), block->expr);
break;
case '~':
consume('~');
block = cast_expression(block);
block->expr = eval_expr(block, IR_NOT, block->expr);
break;
case '+':
consume('+');
block = cast_expression(block);
block->expr.lvalue = 0;
break;
case '-':
consume('-');
block = cast_expression(block);
block->expr = eval_expr(block, IR_OP_SUB, var_int(0), block->expr);
break;
case SIZEOF: {
struct typetree *type;
struct block *head = cfg_block_init(), *tail;
consume(SIZEOF);
if (peek().token == '(') {
switch (peekn(2).token) {
case FIRST(type_name):
consume('(');
type = declaration_specifiers(NULL);
if (peek().token != ')') {
type = declarator(type, NULL);
}
consume(')');
break;
default:
tail = unary_expression(head);
type = (struct typetree *) tail->expr.type;
break;
}
} else {
tail = unary_expression(head);
type = (struct typetree *) tail->expr.type;
}
if (is_function(type)) {
error("Cannot apply 'sizeof' to function type.");
}
if (!size_of(type)) {
error("Cannot apply 'sizeof' to incomplete type.");
}
block->expr = var_int(size_of(type));
break;
}
case INCREMENT:
consume(INCREMENT);
block = unary_expression(block);
value = block->expr;
block->expr = eval_expr(block, IR_OP_ADD, value, var_int(1));
block->expr = eval_assign(block, value, block->expr);
break;
case DECREMENT:
consume(DECREMENT);
block = unary_expression(block);
value = block->expr;
block->expr = eval_expr(block, IR_OP_SUB, value, var_int(1));
block->expr = eval_assign(block, value, block->expr);
break;
default:
block = postfix_expression(block);
break;
}
return block;
}
static struct block *postfix_expression(struct block *block)
{
struct var root;
block = primary_expression(block);
root = block->expr;
while (1) {
const struct member *field;
const struct typetree *type;
struct var expr, copy, *arg;
struct token tok;
int i, j;
switch ((tok = peek()).token) {
case '[':
do {
/* Evaluate a[b] = *(a + b). The semantics of pointer arithmetic
* takes care of multiplying b with the correct width. */
consume('[');
block = expression(block);
root = eval_expr(block, IR_OP_ADD, root, block->expr);
root = eval_deref(block, root);
consume(']');
} while (peek().token == '[');
break;
case '(':
type = root.type;
if (is_pointer(root.type) && is_function(root.type->next))
type = type_deref(root.type);
else if (!is_function(root.type)) {
error("Expression must have type pointer to function, was %t.",
root.type);
exit(1);
}
consume('(');
arg = calloc(nmembers(type), sizeof(*arg));
for (i = 0; i < nmembers(type); ++i) {
if (peek().token == ')') {
error("Too few arguments, expected %d but got %d.",
nmembers(type), i);
exit(1);
}
block = assignment_expression(block);
arg[i] = block->expr;
/* todo: type check here. */
if (i < nmembers(type) - 1) {
consume(',');
}
}
while (is_vararg(type) && peek().token != ')') {
consume(',');
arg = realloc(arg, (i + 1) * sizeof(*arg));
block = assignment_expression(block);
arg[i] = block->expr;
i++;
}
consume(')');
for (j = 0; j < i; ++j)
param(block, arg[j]);
free(arg);
root = eval_call(block, root);
break;
case '.':
consume('.');
tok = consume(IDENTIFIER);
field = find_type_member(root.type, tok.strval);
if (!field) {
error("Invalid field access, no member named '%s'.",
tok.strval);
exit(1);
}
root.type = field->type;
root.offset += field->offset;
break;
case ARROW:
consume(ARROW);
tok = consume(IDENTIFIER);
if (is_pointer(root.type) && is_struct_or_union(root.type->next)) {
field = find_type_member(type_deref(root.type), tok.strval);
if (!field) {
error("Invalid field access, no member named '%s'.",
tok.strval);
exit(1);
}
/* Make it look like a pointer to the field type, then perform
* normal dereferencing. */
root.type = type_init(T_POINTER, field->type);
root = eval_deref(block, root);
root.offset = field->offset;
} else {
error("Invalid field access.");
exit(1);
}
break;
case INCREMENT:
consume(INCREMENT);
copy = create_var(root.type);
eval_assign(block, copy, root);
expr = eval_expr(block, IR_OP_ADD, root, var_int(1));
eval_assign(block, root, expr);
root = copy;
break;
case DECREMENT:
consume(DECREMENT);
copy = create_var(root.type);
eval_assign(block, copy, root);
expr = eval_expr(block, IR_OP_SUB, root, var_int(1));
eval_assign(block, root, expr);
root = copy;
break;
default:
block->expr = root;
return block;
}
}
}
/**
Evaluate an expression in a given frame
*/
value_t eval_expr(
heapptr_t expr,
clos_t* clos,
value_t* locals
)
{
//printf("eval_expr\n");
// Get the shape of the AST node
// Note: AST nodes must match the shapes defined in init_parser,
// otherwise this interpreter can't handle it
shapeidx_t shape = get_shape(expr);
// Variable or constant declaration (let/var)
if (shape == SHAPE_AST_DECL)
{
ast_decl_t* decl = (ast_decl_t*)expr;
// Let declarations should be initialized
assert (decl->cst == false);
return VAL_FALSE;
}
// Variable reference (read)
if (shape == SHAPE_AST_REF)
{
ast_ref_t* ref = (ast_ref_t*)expr;
assert (ref->decl != NULL);
//printf("evaluating ref to %s\n", string_cstr(ref->name));
// If this is a variable from an outer function
if (ref->decl->fun != clos->fun)
{
//printf("ref from outer fun\n");
assert (ref->idx < clos->fun->free_vars->len);
cell_t* cell = clos->cells[ref->idx];
assert (cell != NULL);
value_t value;
value.word = cell->word;
value.tag = cell->tag;
return value;
}
// Check that the ref index is valid
if (ref->idx > clos->fun->local_decls->len)
{
printf("invalid variable reference\n");
printf("ref->name=%s\n", string_cstr(ref->name));
printf("ref->idx=%d\n", ref->idx);
printf("local_decls->len=%d\n", clos->fun->local_decls->len);
exit(-1);
}
// If this an escaping variable (captured by a closure)
if (ref->decl->esc)
{
// Free variables are stored in mutable cells
// Pointers to the cells are found on the closure object
cell_t* cell = locals[ref->idx].word.cell;
value_t value;
value.word = cell->word;
value.tag = cell->tag;
//printf("read value from cell\n");
return value;
}
/*
printf("reading normal local\n");
string_print(ref->name);
printf("\n");
*/
// Read directly from the stack frame
return locals[ref->idx];
}
if (shape == SHAPE_AST_CONST)
{
//printf("constant\n");
ast_const_t* cst = (ast_const_t*)expr;
return cst->val;
}
if (shape == SHAPE_STRING)
{
return value_from_heapptr(expr, TAG_STRING);
}
// Array literal expression
if (shape == SHAPE_ARRAY)
{
array_t* array_expr = (array_t*)expr;
// Array of values to be produced
array_t* val_array = array_alloc(array_expr->len);
for (size_t i = 0; i < array_expr->len; ++i)
{
heapptr_t expr = array_get(array_expr, i).word.heapptr;
value_t value = eval_expr(expr, clos, locals);
array_set(val_array, i, value);
}
return value_from_heapptr((heapptr_t)val_array, TAG_ARRAY);
}
// Object literal expression
if (shape == SHAPE_AST_OBJ)
{
//printf("obj literal expr\n");
ast_obj_t* obj_expr = (ast_obj_t*)expr;
object_t* obj = object_alloc(OBJ_MIN_CAP);
// TODO: set prototype
// Do this in object_alloc?
for (size_t i = 0; i < obj_expr->name_strs->len; ++i)
{
string_t* prop_name = array_get(obj_expr->name_strs, i).word.string;
heapptr_t val_expr = array_get(obj_expr->val_exprs, i).word.heapptr;
value_t value = eval_expr(val_expr, clos, locals);
object_set_prop(
obj,
prop_name,
value,
ATTR_DEFAULT
);
}
return value_from_obj((heapptr_t)obj);
}
// Binary operator (e.g. a + b)
if (shape == SHAPE_AST_BINOP)
{
//printf("binop\n");
ast_binop_t* binop = (ast_binop_t*)expr;
// Assignment
if (binop->op == &OP_ASSIGN)
{
value_t val = eval_expr(binop->right_expr, clos, locals);
return eval_assign(
binop->left_expr,
val,
clos,
locals
);
}
value_t v0 = eval_expr(binop->left_expr, clos, locals);
value_t v1 = eval_expr(binop->right_expr, clos, locals);
int64_t i0 = v0.word.int64;
int64_t i1 = v1.word.int64;
string_t* s0 = v0.word.string;
string_t* s1 = v1.word.string;
if (binop->op == &OP_MEMBER)
return eval_get_prop(v0, v1);
if (binop->op == &OP_INDEX)
return eval_get_index(v0, v1);
if (binop->op == &OP_ADD)
return value_from_int64(i0 + i1);
if (binop->op == &OP_SUB)
return value_from_int64(i0 - i1);
if (binop->op == &OP_MUL)
return value_from_int64(i0 * i1);
if (binop->op == &OP_DIV)
return value_from_int64(i0 / i1);
if (binop->op == &OP_MOD)
return value_from_int64(i0 % i1);
if (binop->op == &OP_LT)
return (i0 < i1)? VAL_TRUE:VAL_FALSE;
if (binop->op == &OP_LE)
{
if (v0.tag == TAG_STRING && v1.tag == TAG_STRING)
return (strcmp(string_cstr(s0), string_cstr(s1)) <= 0)? VAL_TRUE:VAL_FALSE;
if (v0.tag == TAG_INT64 && v1.tag == TAG_INT64)
return (i0 <= i1)? VAL_TRUE:VAL_FALSE;
assert (false);
}
if (binop->op == &OP_GT)
return (i0 > i1)? VAL_TRUE:VAL_FALSE;
if (binop->op == &OP_GE)
{
if (v0.tag == TAG_STRING && v1.tag == TAG_STRING)
return (strcmp(string_cstr(s0), string_cstr(s1)) >= 0)? VAL_TRUE:VAL_FALSE;
if (v0.tag == TAG_INT64 && v1.tag == TAG_INT64)
return (i0 >= i1)? VAL_TRUE:VAL_FALSE;
assert (false);
}
if (binop->op == &OP_EQ)
return value_equals(v0, v1)? VAL_TRUE:VAL_FALSE;
if (binop->op == &OP_NE)
return value_equals(v0, v1)? VAL_FALSE:VAL_TRUE;
printf("unimplemented binary operator: %s\n", binop->op->str);
return VAL_FALSE;
}
// Unary operator (e.g.: -x, not a)
if (shape == SHAPE_AST_UNOP)
{
ast_unop_t* unop = (ast_unop_t*)expr;
value_t v0 = eval_expr(unop->expr, clos, locals);
if (unop->op == &OP_NEG)
return value_from_int64(-v0.word.int64);
if (unop->op == &OP_NOT)
return eval_truth(v0)? VAL_FALSE:VAL_TRUE;
printf("unimplemented unary operator: %s\n", unop->op->str);
return VAL_FALSE;
}
// Sequence/block expression
if (shape == SHAPE_AST_SEQ)
{
ast_seq_t* seqexpr = (ast_seq_t*)expr;
array_t* expr_list = seqexpr->expr_list;
value_t value = VAL_TRUE;
for (size_t i = 0; i < expr_list->len; ++i)
{
heapptr_t expr = array_get(expr_list, i).word.heapptr;
value = eval_expr(expr, clos, locals);
}
// Return the value of the last expression
return value;
}
// If expression
if (shape == SHAPE_AST_IF)
{
ast_if_t* ifexpr = (ast_if_t*)expr;
value_t t = eval_expr(ifexpr->test_expr, clos, locals);
if (eval_truth(t))
return eval_expr(ifexpr->then_expr, clos, locals);
else
return eval_expr(ifexpr->else_expr, clos, locals);
}
// Function/closure expression
if (shape == SHAPE_AST_FUN)
{
//printf("creating closure\n");
ast_fun_t* nested = (ast_fun_t*)expr;
// Allocate a closure of the nested function
clos_t* new_clos = clos_alloc(nested);
// For each free (closure) variable of the nested function
for (size_t i = 0; i < nested->free_vars->len; ++i)
{
ast_decl_t* decl = array_get(nested->free_vars, i).word.decl;
// If the variable is from this function
if (decl->fun == clos->fun)
{
new_clos->cells[i] = locals[decl->idx].word.cell;
}
else
{
uint32_t free_idx = array_indexof_ptr(clos->fun->free_vars, (heapptr_t)decl);
assert (free_idx < clos->fun->free_vars->len);
new_clos->cells[i] = clos->cells[free_idx];
}
}
assert (new_clos->fun == nested);
return value_from_heapptr((heapptr_t)new_clos, TAG_CLOS);
}
// Call expression
if (shape == SHAPE_AST_CALL)
{
//printf("evaluating call\n");
ast_call_t* callexpr = (ast_call_t*)expr;
// Evaluate the closure expression
value_t callee_clos = eval_expr(callexpr->fun_expr, clos, locals);
if (callee_clos.tag == TAG_CLOS)
{
return eval_call(
callee_clos.word.clos,
callexpr->arg_exprs,
clos,
locals
);
}
if (callee_clos.tag == TAG_HOSTFN)
{
return eval_host_call(
callee_clos.word.hostfn,
callexpr->arg_exprs,
clos,
locals
);
}
printf("invalid callee in function call\n");
exit(-1);
}
printf("eval error, unknown expression type, shapeidx=%d\n", get_shape(expr));
exit(-1);
}
static void member_declaration_list(struct typetree *type)
{
struct namespace ns = {0};
struct typetree *decl_base, *decl_type;
const char *name;
push_scope(&ns);
do {
decl_base = declaration_specifiers(NULL);
do {
name = NULL;
decl_type = declarator(decl_base, &name);
if (!name) {
error("Missing name in member declarator.");
exit(1);
} else if (!size_of(decl_type)) {
error("Field '%s' has incomplete type '%t'.", name, decl_type);
exit(1);
} else {
sym_add(&ns, name, decl_type, SYM_DECLARATION, LINK_NONE);
type_add_member(type, name, decl_type);
}
if (peek().token == ',') {
consume(',');
continue;
}
} while (peek().token != ';');
consume(';');
} while (peek().token != '}');
pop_scope(&ns);
}
static struct typetree *struct_or_union_declaration(void)
{
struct symbol *sym = NULL;
struct typetree *type = NULL;
enum type kind =
(next().token == STRUCT) ? T_STRUCT : T_UNION;
if (peek().token == IDENTIFIER) {
const char *name = consume(IDENTIFIER).strval;
sym = sym_lookup(&ns_tag, name);
if (!sym) {
type = type_init(kind);
sym = sym_add(&ns_tag, name, type, SYM_TYPEDEF, LINK_NONE);
} else if (is_integer(&sym->type)) {
error("Tag '%s' was previously declared as enum.", sym->name);
exit(1);
} else if (sym->type.type != kind) {
error("Tag '%s' was previously declared as %s.",
sym->name, (sym->type.type == T_STRUCT) ? "struct" : "union");
exit(1);
}
/* Retrieve type from existing symbol, possibly providing a complete
* definition that will be available for later declarations. Overwrites
* existing type information from symbol table. */
type = &sym->type;
if (peek().token == '{' && type->size) {
error("Redefiniton of '%s'.", sym->name);
exit(1);
}
}
if (peek().token == '{') {
if (!type) {
/* Anonymous structure; allocate a new standalone type,
* not part of any symbol. */
type = type_init(kind);
}
consume('{');
member_declaration_list(type);
assert(type->size);
consume('}');
}
/* Return to the caller a copy of the root node, which can be overwritten
* with new type qualifiers without altering the tag registration. */
return (sym) ? type_tagged_copy(&sym->type, sym->name) : type;
}
static void enumerator_list(void)
{
struct var val;
struct symbol *sym;
int enum_value = 0;
consume('{');
do {
const char *name = consume(IDENTIFIER).strval;
if (peek().token == '=') {
consume('=');
val = constant_expression();
if (!is_integer(val.type)) {
error("Implicit conversion from non-integer type in enum.");
}
enum_value = val.imm.i;
}
sym = sym_add(
&ns_ident,
name,
&basic_type__int,
SYM_ENUM_VALUE,
LINK_NONE);
sym->enum_value = enum_value++;
if (peek().token != ',')
break;
consume(',');
} while (peek().token != '}');
consume('}');
}
static struct typetree *enum_declaration(void)
{
struct typetree *type = type_init(T_SIGNED, 4);
consume(ENUM);
if (peek().token == IDENTIFIER) {
struct symbol *tag = NULL;
const char *name = consume(IDENTIFIER).strval;
tag = sym_lookup(&ns_tag, name);
if (!tag || tag->depth < ns_tag.current_depth) {
tag = sym_add(&ns_tag, name, type, SYM_TYPEDEF, LINK_NONE);
} else if (!is_integer(&tag->type)) {
error("Tag '%s' was previously defined as aggregate type.",
tag->name);
exit(1);
}
/* Use enum_value as a sentinel to represent definition, checked on
* lookup to detect duplicate definitions. */
if (peek().token == '{') {
if (tag->enum_value) {
error("Redefiniton of enum '%s'.", tag->name);
}
enumerator_list();
tag->enum_value = 1;
}
} else {
enumerator_list();
}
/* Result is always integer. Do not care about the actual enum definition,
* all enums are ints and no type checking is done. */
return type;
}
static struct typetree get_basic_type_from_specifier(unsigned short spec)
{
switch (spec) {
case 0x0001: /* void */
return basic_type__void;
case 0x0002: /* char */
case 0x0012: /* signed char */
return basic_type__char;
case 0x0022: /* unsigned char */
return basic_type__unsigned_char;
case 0x0004: /* short */
case 0x0014: /* signed short */
case 0x000C: /* short int */
case 0x001C: /* signed short int */
return basic_type__short;
case 0x0024: /* unsigned short */
case 0x002C: /* unsigned short int */
return basic_type__unsigned_short;
case 0x0008: /* int */
case 0x0010: /* signed */
case 0x0018: /* signed int */
return basic_type__int;
case 0x0020: /* unsigned */
case 0x0028: /* unsigned int */
return basic_type__unsigned_int;
case 0x0040: /* long */
case 0x0050: /* signed long */
case 0x0048: /* long int */
case 0x0058: /* signed long int */
case 0x00C0: /* long long */
case 0x00D0: /* signed long long */
case 0x00D8: /* signed long long int */
return basic_type__long;
case 0x0060: /* unsigned long */
case 0x0068: /* unsigned long int */
case 0x00E0: /* unsigned long long */
case 0x00E8: /* unsigned long long int */
return basic_type__unsigned_long;
case 0x0100: /* float */
return basic_type__float;
case 0x0200: /* double */
case 0x0240: /* long double */
return basic_type__double;
default:
error("Invalid type specification.");
exit(1);
}
}
/* Parse type, qualifiers and storage class. Do not assume int by default, but
* require at least one type specifier. Storage class is returned as token
* value, unless the provided pointer is NULL, in which case the input is parsed
* as specifier-qualifier-list.
*/
struct typetree *declaration_specifiers(int *stc)
{
struct typetree *type = NULL;
struct token tok;
int done = 0;
/* Use a compact bit representation to hold state about declaration
* specifiers. Initialize storage class to sentinel value. */
unsigned short spec = 0x0000;
enum qualifier qual = Q_NONE;
if (stc) *stc = '$';
#define set_specifier(d) \
if (spec & d) error("Duplicate type specifier '%s'.", tok.strval); \
next(); spec |= d;
#define set_qualifier(d) \
if (qual & d) error("Duplicate type qualifier '%s'.", tok.strval); \
next(); qual |= d;
#define set_storage_class(t) \
if (!stc) error("Unexpected storage class in qualifier list."); \
else if (*stc != '$') error("Multiple storage class specifiers."); \
next(); *stc = t;
do {
switch ((tok = peek()).token) {
case VOID: set_specifier(0x001); break;
case CHAR: set_specifier(0x002); break;
case SHORT: set_specifier(0x004); break;
case INT: set_specifier(0x008); break;
case SIGNED: set_specifier(0x010); break;
case UNSIGNED: set_specifier(0x020); break;
case LONG:
if (spec & 0x040) {
set_specifier(0x080);
} else {
set_specifier(0x040);
}
break;
case FLOAT: set_specifier(0x100); break;
case DOUBLE: set_specifier(0x200); break;
case CONST: set_qualifier(Q_CONST); break;
case VOLATILE: set_qualifier(Q_VOLATILE); break;
case IDENTIFIER: {
struct symbol *tag = sym_lookup(&ns_ident, tok.strval);
if (tag && tag->symtype == SYM_TYPEDEF && !type) {
consume(IDENTIFIER);
type = type_init(T_STRUCT);
*type = tag->type;
} else {
done = 1;
}
break;
}
case UNION:
case STRUCT:
if (!type) {
type = struct_or_union_declaration();
} else {
done = 1;
}
break;
case ENUM:
if (!type) {
type = enum_declaration();
} else {
done = 1;
}
break;
case AUTO:
case REGISTER:
case STATIC:
case EXTERN:
case TYPEDEF:
set_storage_class(tok.token);
break;
default:
done = 1;
break;
}
if (type && spec) {
error("Invalid combination of declaration specifiers.");
exit(1);
}
} while (!done);
#undef set_specifier
#undef set_qualifier
#undef set_storage_class
if (type) {
if (qual & type->qualifier) {
error("Duplicate type qualifier:%s%s.",
(qual & Q_CONST) ? " const" : "",
(qual & Q_VOLATILE) ? " volatile" : "");
}
} else if (spec) {
type = type_init(T_STRUCT);
*type = get_basic_type_from_specifier(spec);
} else {
error("Missing type specifier.");
exit(1);
}
type->qualifier |= qual;
return type;
}
/* Set var = 0, using simple assignment on members for composite types. This
* rule does not consume any input, but generates a series of assignments on the
* given variable. Point is to be able to zero initialize using normal simple
* assignment rules, although IR can become verbose for large structures.
*/
static void zero_initialize(struct block *block, struct var target)
{
int i;
struct var var;
assert(target.kind == DIRECT);
switch (target.type->type) {
case T_STRUCT:
case T_UNION:
target.type = unwrapped(target.type);
var = target;
for (i = 0; i < nmembers(var.type); ++i) {
target.type = get_member(var.type, i)->type;
target.offset = var.offset + get_member(var.type, i)->offset;
zero_initialize(block, target);
}
break;
case T_ARRAY:
assert(target.type->size);
var = target;
target.type = target.type->next;
assert(is_struct(target.type) || !target.type->next);
for (i = 0; i < var.type->size / var.type->next->size; ++i) {
target.offset = var.offset + i * var.type->next->size;
zero_initialize(block, target);
}
break;
case T_POINTER:
var = var_zero(8);
var.type = type_init(T_POINTER, &basic_type__void);
eval_assign(block, target, var);
break;
case T_UNSIGNED:
case T_SIGNED:
var = var_zero(target.type->size);
eval_assign(block, target, var);
break;
default:
error("Invalid type to zero-initialize, was '%t'.", target.type);
exit(1);
}
}
static void
eval_expr(m1_expression *e) {
if (e == NULL)
return;
switch (e->type) {
case EXPR_NUMBER:
eval_number(e->expr.l->value.fval);
break;
case EXPR_INT:
eval_int(e->expr.l->value.ival);
break;
case EXPR_BINARY:
eval_binary(e->expr.b);
break;
case EXPR_UNARY:
eval_unary(e->expr.u);
break;
case EXPR_FUNCALL:
eval_funcall(e->expr.f);
break;
case EXPR_ASSIGN:
eval_assign(e->expr.a);
break;
case EXPR_IF:
eval_if(e->expr.i);
break;
case EXPR_WHILE:
eval_while(e->expr.w);
break;
case EXPR_DOWHILE:
eval_dowhile(e->expr.w);
break;
case EXPR_FOR:
eval_for(e->expr.o);
break;
case EXPR_RETURN:
eval_return(e->expr.e);
break;
case EXPR_NULL:
eval_null();
break;
case EXPR_DEREF:
eval_deref(e->expr.t);
break;
case EXPR_ADDRESS:
eval_address(e->expr.t);
break;
case EXPR_OBJECT:
eval_obj(e->expr.t);
break;
case EXPR_BREAK:
eval_break();
break;
case EXPR_CONTINUE:
eval_continue();
break;
case EXPR_CONSTDECL:
case EXPR_VARDECL:
break;
default:
fprintf(stderr, "unknown expr type");
exit(EXIT_FAILURE);
}
}
