/* subtree - construct tree for l - r */
static Tree subtree(int op, Tree l, Tree r) {
long n;
Type ty = inttype;
if (isarith(l->type) && isarith(r->type)) {
ty = binary(l->type, r->type);
l = cast(l, ty);
r = cast(r, ty);
} else if (isptr(l->type) && !isfunc(l->type->type) && isint(r->type)) {
ty = unqual(l->type);
n = unqual(ty->type)->size;
if (n == 0)
error("unknown size for type `%t'\n", ty->type);
r = cast(r, promote(r->type));
if (n > 1)
r = multree(MUL, cnsttree(signedptr, n), r);
if (isunsigned(r->type))
r = cast(r, unsignedptr);
else
r = cast(r, signedptr);
return simplify(SUB+P, ty, l, r);
} else if (compatible(l->type, r->type)) {
ty = unqual(l->type);
n = unqual(ty->type)->size;
if (n == 0)
error("unknown size for type `%t'\n", ty->type);
l = simplify(SUB+U, unsignedptr,
cast(l, unsignedptr), cast(r, unsignedptr));
return simplify(DIV+I, longtype,
cast(l, longtype), cnsttree(longtype, n));
} else
typeerror(op, l, r);
return simplify(op, ty, l, r);
}
Tree asgntree(int op, Tree l, Tree r) {
Type aty, ty;
r = pointer(r);
ty = assign(l->type, r);
if (ty)
r = cast(r, ty);
else {
typeerror(ASGN, l, r);
if (r->type == voidtype)
r = retype(r, inttype);
ty = r->type;
}
if (l->op != FIELD)
l = lvalue(l);
aty = l->type;
if (isptr(aty))
aty = unqual(aty)->type;
if (isconst(aty)
|| (isstruct(aty) && unqual(aty)->u.sym->u.s.cfields)) {
if (isaddrop(l->op)
&& !l->u.sym->computed && !l->u.sym->generated)
error("assignment to const identifier `%s'\n",
l->u.sym->name);
else
error("assignment to const location\n");
}
if (l->op == FIELD) {
long n = 8 * l->u.field->type->size - fieldsize(l->u.field);
if (n > 0 && isunsigned(l->u.field->type))
r = bittree(BAND, r,
cnsttree(r->type, (unsigned long)fieldmask(l->u.field)));
else if (n > 0) {
if (r->op == CNST + I) {
n = r->u.v.i;
if (n & (1 << (fieldsize(l->u.field) - 1)))
n |= ~0UL << fieldsize(l->u.field);
r = cnsttree(r->type, n);
} else
r = shtree(RSH,
shtree(LSH, r, cnsttree(inttype, n)),
cnsttree(inttype, n));
}
}
if (isstruct(ty) && isaddrop(l->op) && iscallb(r))
return tree(RIGHT, ty,
tree(CALL + B, ty, r->kids[0]->kids[0], l),
idtree(l->u.sym));
return tree(mkop(op, ty), ty, l, r);
}
static Tree addtree(int op, Tree l, Tree r) {
Type ty = inttype;
if (isarith(l->type) && isarith(r->type)) {
ty = binary(l->type, r->type);
l = cast(l, ty);
r = cast(r, ty);
} else if (isptr(l->type) && isint(r->type))
return addtree(ADD, r, l);
else if ( isptr(r->type) && isint(l->type)
&& !isfunc(r->type->type))
{
long n;
ty = unqual(r->type);
n = unqual(ty->type)->size;
if (n == 0)
error("unknown size for type `%t'\n", ty->type);
l = cast(l, promote(l->type));
if (n > 1)
l = multree(MUL, cnsttree(signedptr, n), l);
if (isunsigned(l->type))
l = cast(l, unsignedptr);
else
l = cast(l, signedptr);
if (YYcheck && !isaddrop(r->op)) /* omit */
return nullcall(ty, YYcheck, r, l); /* omit */
return simplify(ADD, ty, l, r);
}
else
typeerror(op, l, r);
return simplify(op, ty, l, r);
}
static void cmp(int op, Symbol p, long n, int lab) {
Type ty = signedint(p->type);
listnodes(eqtree(op,
cast(idtree(p), ty),
cnsttree(ty, n)),
lab, 0);
}
/* call_hook - called at function calls.
If *e is a call, call_hook changes the expression to the equivalent of
the C expression
(tos.ip = i, *e)
where i is the stopping point index for the execution point of the
expression in which the call appears.
*/
static void call_hook(void *cl, Coordinate *cp, Tree *e) {
assert(*e);
*e = tree(RIGHT, (*e)->type,
asgntree(ASGN,
field(lvalue(idtree(tos)), string("ip")),
cnsttree(inttype, Seq_length(pickle->spoints))),
*e);
}
/* point_hook - called at each execution point */
static void point_hook(void *cl, Coordinate *cp, Tree *e) {
Tree t;
/*
add breakpoint test to *e:
(_Nub_bpflags[i] != 0 && _Nub_bp(i), *e)
*/
t = tree(AND, voidtype,
(*optree[NEQ])(NE,
rvalue((*optree['+'])(ADD,
pointer(idtree(nub_bpflags)),
cnsttree(inttype, Seq_length(pickle->spoints)))),
cnsttree(inttype, 0L)),
vcall(nub_bp, voidtype, cnsttree(inttype, Seq_length(pickle->spoints)), NULL));
if (*e)
*e = tree(RIGHT, (*e)->type, t, *e);
else
*e = t;
Seq_addhi(pickle->spoints,
sym_spoint(sym_coordinate(cp->file ? cp->file : string(""), cp->x, cp->y), tail()));
}
/* entry_hook - called an function entry */
static void entry_hook(void *cl, Symbol cfunc) {
static int nfuncs;
Type ty;
/*
Simulate the declaration of an sframe structure,
but without the tag.
*/
ty = newstruct(STRUCT, "");
#define addfield(name,t) \
ty->size = roundup(ty->size, t->align);\
if (ty->align < t->align) ty->align = t->align; \
newfield(string(name), ty, t)->offset = ty->size; \
ty->size += t->size
addfield("up", voidptype);
addfield("down", voidptype);
addfield("func", inttype);
addfield("module",inttype);
addfield("ip", inttype);
#undef addfield
ty->size = roundup(ty->size, ty->align);
ty->u.sym->defined = 1;
ty->u.sym->generated = 1;
tos = genident(AUTO, ty, LOCAL);
addlocal(tos);
tos->defined = 1;
/*
Generated the assignments to the shadow
frame fields.
*/
#define set(name,e) walk(asgntree(ASGN,field(lvalue(idtree(tos)),string(#name)),(e)),0,0)
set(down, idtree(nub_tos));
set(func, cnsttree(inttype, symboluid(cfunc)));
set(module, cnsttree(inttype, uname));
#undef set
walk(asgn(nub_tos, lvalue(idtree(tos))), 0, 0);
foreach(identifiers, PARAM, setoffset, tos);
}
Tree unary(void) {
Tree p;
switch (t) {
case '*': t = gettok(); p = unary(); p = pointer(p);
if (isptr(p->type)
&& (isfunc(p->type->type) || isarray(p->type->type)))
p = retype(p, p->type->type);
else {
if (YYnull)
p = nullcheck(p);
p = rvalue(p);
} break;
case '&': t = gettok(); p = unary(); if (isarray(p->type) || isfunc(p->type))
p = retype(p, ptr(p->type));
else
p = lvalue(p);
if (isaddrop(p->op) && p->u.sym->sclass == REGISTER)
error("invalid operand of unary &; `%s' is declared register\n", p->u.sym->name);
else if (isaddrop(p->op))
p->u.sym->addressed = 1;
break;
case '+': t = gettok(); p = unary(); p = pointer(p);
if (isarith(p->type))
p = cast(p, promote(p->type));
else
typeerror(ADD, p, NULL); break;
case '-': t = gettok(); p = unary(); p = pointer(p);
if (isarith(p->type)) {
Type ty = promote(p->type);
p = cast(p, ty);
if (isunsigned(ty)) {
warning("unsigned operand of unary -\n");
p = simplify(ADD, ty, simplify(BCOM, ty, p, NULL), cnsttree(ty, 1UL));
} else
p = simplify(NEG, ty, p, NULL);
} else
typeerror(SUB, p, NULL); break;
case '~': t = gettok(); p = unary(); p = pointer(p);
if (isint(p->type)) {
Type ty = promote(p->type);
p = simplify(BCOM, ty, cast(p, ty), NULL);
} else
typeerror(BCOM, p, NULL); break;
case '!': t = gettok(); p = unary(); p = pointer(p);
if (isscalar(p->type))
p = simplify(NOT, inttype, cond(p), NULL);
else
typeerror(NOT, p, NULL); break;
case INCR: t = gettok(); p = unary(); p = incr(INCR, pointer(p), consttree(1, inttype)); break;
case DECR: t = gettok(); p = unary(); p = incr(DECR, pointer(p), consttree(1, inttype)); break;
case TYPECODE: case SIZEOF: { int op = t;
Type ty;
p = NULL;
t = gettok();
if (t == '(') {
t = gettok();
if (istypename(t, tsym)) {
ty = typename();
expect(')');
} else {
p = postfix(expr(')'));
ty = p->type;
}
} else {
void swcode(Swtch swp, int b[], int lb, int ub) {
int hilab, lolab, l, u, k = (lb + ub)/2;
long *v = swp->values;
if (k > lb && k < ub) {
lolab = genlabel(1);
hilab = genlabel(1);
} else if (k > lb) {
lolab = genlabel(1);
hilab = swp->deflab->u.l.label;
} else if (k < ub) {
lolab = swp->deflab->u.l.label;
hilab = genlabel(1);
} else
lolab = hilab = swp->deflab->u.l.label;
l = b[k];
u = b[k+1] - 1;
if (u - l + 1 <= 3)
{
int i;
for (i = l; i <= u; i++)
cmp(EQ, swp->sym, v[i], swp->labels[i]->u.l.label);
if (k > lb && k < ub)
cmp(GT, swp->sym, v[u], hilab);
else if (k > lb)
cmp(GT, swp->sym, v[u], hilab);
else if (k < ub)
cmp(LT, swp->sym, v[l], lolab);
else
assert(lolab == hilab),
branch(lolab);
walk(NULL, 0, 0);
}
else {
Tree e;
Type ty = signedint(swp->sym->type);
Symbol table = genident(STATIC,
array(voidptype, u - l + 1, 0), GLOBAL);
(*IR->defsymbol)(table);
if (!isunsigned(swp->sym->type) || v[l] != 0)
cmp(LT, swp->sym, v[l], lolab);
cmp(GT, swp->sym, v[u], hilab);
e = (*optree['-'])(SUB, cast(idtree(swp->sym), ty), cnsttree(ty, v[l]));
if (e->type->size < unsignedptr->size)
e = cast(e, unsignedlong);
walk(tree(JUMP, voidtype,
rvalue((*optree['+'])(ADD, pointer(idtree(table)), e)), NULL),
0, 0);
code(Switch);
codelist->u.swtch.table = table;
codelist->u.swtch.sym = swp->sym;
codelist->u.swtch.deflab = swp->deflab;
codelist->u.swtch.size = u - l + 1;
codelist->u.swtch.values = &v[l];
codelist->u.swtch.labels = &swp->labels[l];
if (v[u] - v[l] + 1 >= 10000)
warning("switch generates a huge table\n");
}
if (k > lb) {
assert(lolab != swp->deflab->u.l.label);
definelab(lolab);
swcode(swp, b, lb, k - 1);
}
if (k < ub) {
assert(hilab != swp->deflab->u.l.label);
definelab(hilab);
swcode(swp, b, k + 1, ub);
}
}
Tree consttree(unsigned n, Type ty) {
if (isarray(ty))
ty = atop(ty);
else assert(isint(ty));
return cnsttree(ty, (unsigned long)n);
}
void statement(int loop, Swtch swp, int lev) {
float ref = refinc;
if (Aflag >= 2 && lev == 15)
warning("more than 15 levels of nested statements\n");
switch (t) {
case IF: ifstmt(genlabel(2), loop, swp, lev + 1);
break;
case WHILE: whilestmt(genlabel(3), swp, lev + 1); break;
case DO: dostmt(genlabel(3), swp, lev + 1); expect(';');
break;
case FOR: forstmt(genlabel(4), swp, lev + 1);
break;
case BREAK: walk(NULL, 0, 0);
definept(NULL);
if (swp && swp->lab > loop)
branch(swp->lab + 1);
else if (loop)
branch(loop + 2);
else
error("illegal break statement\n");
t = gettok(); expect(';');
break;
case CONTINUE: walk(NULL, 0, 0);
definept(NULL);
if (loop)
branch(loop + 1);
else
error("illegal continue statement\n");
t = gettok(); expect(';');
break;
case SWITCH: swstmt(loop, genlabel(2), lev + 1);
break;
case CASE: {
int lab = genlabel(1);
if (swp == NULL)
error("illegal case label\n");
definelab(lab);
while (t == CASE) {
static char stop[] = { IF, ID, 0 };
Tree p;
t = gettok();
p = constexpr(0);
if (generic(p->op) == CNST && isint(p->type)) {
if (swp) {
needconst++;
p = cast(p, swp->sym->type);
if (p->type->op == UNSIGNED)
p->u.v.i = extend(p->u.v.u, p->type);
needconst--;
caselabel(swp, p->u.v.i, lab);
}
} else
error("case label must be a constant integer expression\n");
test(':', stop);
}
statement(loop, swp, lev);
} break;
case DEFAULT: if (swp == NULL)
error("illegal default label\n");
else if (swp->deflab)
error("extra default label\n");
else {
swp->deflab = findlabel(swp->lab);
definelab(swp->deflab->u.l.label);
}
t = gettok();
expect(':');
statement(loop, swp, lev); break;
case RETURN: {
Type rty = freturn(cfunc->type);
t = gettok();
definept(NULL);
if (t != ';')
if (rty == voidtype) {
error("extraneous return value\n");
expr(0);
retcode(NULL);
} else
retcode(expr(0));
else {
if (rty != voidtype) {
warning("missing return value\n");
retcode(cnsttree(inttype, 0L));
} else
retcode(NULL);
}
branch(cfunc->u.f.label);
} expect(';');
break;
case '{': compound(loop, swp, lev + 1); break;
case ';': definept(NULL); t = gettok(); break;
case GOTO: walk(NULL, 0, 0);
definept(NULL);
t = gettok();
if (t == ID) {
Symbol p = lookup(token, stmtlabs);
if (p == NULL) {
p = install(token, &stmtlabs, 0, FUNC);
p->scope = LABELS;
p->u.l.label = genlabel(1);
p->src = src;
}
use(p, src);
branch(p->u.l.label);
t = gettok();
} else
error("missing label in goto\n"); expect(';');
break;
case ID: if (getchr() == ':') {
stmtlabel();
statement(loop, swp, lev);
break;
}
default: definept(NULL);
if (kind[t] != ID) {
error("unrecognized statement\n");
t = gettok();
} else {
Tree e = expr0(0);
listnodes(e, 0, 0);
if (nodecount == 0 || nodecount > 200)
walk(NULL, 0, 0);
else if (glevel) walk(NULL, 0, 0);
deallocate(STMT);
} expect(';');
break;
}
if (kind[t] != IF && kind[t] != ID
&& t != '}' && t != EOI) {
static char stop[] = { IF, ID, '}', 0 };
error("illegal statement termination\n");
skipto(0, stop);
}
refinc = ref;
}
