ack/lang/cem/cemcom.ansi/ch3bin.c
George Koehler 15950f9c95 Add long long literals like 123LL to ACK C.
For now, a long long literal must have the 'LL' or 'll' suffix.  A
literal without 'LL' or 'll' acts as before: it may become unsigned
long but not long long.  (For targets where int and long have the same
size, some literals change from unsigned int to unsigned long.)

Type `arith` may be too narrow for long long values.  Add a second
type `writh` for wide arithmetic, and change some variables from arith
to writh.  This may cause bugs if I forget to use writh, or if a
conversion from writh to arith overflows.  I mark some conversions
with (arith) or (writh) casts.

 - BigPars, SmallPars: Remove SPECIAL_ARITHMETICS.  This feature
   would change arith to a different type, but can't work, because it
   would conflict with definitions of arith in both <em_arith.h> and
   <flt_arith.h>.
 - LLlex.c: Understand 'LL' or 'll' suffix.  Cut size of constant when
   it overflows writh, not only when it overflows the target machine's
   types.  (This cut might not be necessary, because we might cut it
   again later.)  When picking signed long or unsigned long, check the
   target's long type, not the compiler's arith type; the old check
   for `val >= 0` was broken where sizeof(arith) > 4.
 - LLlex.h: Change struct token's tok_ival to writh, so it can hold a
   long long literal.
 - arith.c: Adjust to VL_VALUE being writh.  Don't convert between
   float and integer at compile-time if the integer might be too wide
   for <flt_arith.h>.  Add writh2str(), because writh might be too
   wide for long2str().
 - arith.h: Remove SPECIAL_ARITHMETICS.  Declare full_mask[] here,
   not in several *.c files.  Declare writh2str().
 - ch3.c, ch3bin.c, ch3mon.c, declarator.c, statement.g: Remove
   obsolete casts.  Adjust to VL_VALUE being writh.
 - conversion.c, stab.c: Don't declare full_mask[].
 - cstoper.c: Use writh for constant operations on VL_VALUE, and for
   full_mask[].
 - declar., field.c, ival.g: Add casts.
 - dumpidf.c: Need to #include "parameters.h" before checking DEBUG.
   Use writh2str, because "%ld" might not work.
 - eval.c, eval.h: Add casts.  Use writh when writing a wide constant
   in EM.
 - expr.c: Add and remove casts.  In fill_int_expr(), make expression
   from long long literal.  In chk_cst_expr(), allow long long as
   constant expression, so the compiler may accept `case 123LL:` in a
   switch statement.
 - expr.str: Change struct value's vl_value and struct expr's VL_VALUE
   to writh, so an expression may have a long long value at compile
   time.
 - statement.g: Remove obsolete casts.
 - switch.c, switch.str: Use writh in case entries for switch
   statements, so `switch (ll) {...}` with long long ll works.
 - tokenname.c: Add ULNGLNG so LLlex.c can use it for literals.
2019-09-04 22:14:38 -04:00

398 lines
9.8 KiB
C

/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/* $Id$ */
/* SEMANTIC ANALYSIS (CHAPTER 3.3) -- BINARY OPERATORS */
#include "parameters.h"
#include <alloc.h>
#include <flt_arith.h>
#include "arith.h"
#include "type.h"
#include "struct.h"
#include "label.h"
#include "expr.h"
#include "Lpars.h"
#include "sizes.h"
#include "ch3bin.h"
#include "ch3mon.h"
#include "ch3.h"
#include "error.h"
#include "cstoper.h"
#include "fltcstoper.h"
extern char options[];
extern char *symbol2str();
void pntminuspnt();
/* This chapter asks for the repeated application of code to handle
an operation that may be executed at compile time or at run time,
depending on the constancy of the operands.
*/
/*
* Although the relational operators are generally not commutative, we can
* switch the arguments if the operator is adapted (e.g. < becomes >)
*/
#define non_commutative_binop(expp, oper, expr) mk_binop(expp, oper, expr, 0)
#define commutative_binop(expp, oper, expr) mk_binop(expp, oper, expr, 1)
#define non_commutative_relop(expp, oper, expr) mk_binop(expp, oper, expr, 1)
void ch3bin(register struct expr **expp, int oper, struct expr *expr)
{
/* apply binary operator oper between *expp and expr.
NB: don't swap operands if op is one of the op= operators!!!
*/
register struct type *expp_tp;
any2opnd(expp, oper);
expp_tp = (*expp)->ex_type;
/* expp_tp can never be ARRAY, since any2opnd() converts the type
* to pointer (except for SIZEOF and unary &).
*/
any2opnd(&expr, oper);
switch (oper) {
case '[': /* 3.3.2.1 */
/* indexing follows the commutative laws */
switch (expp_tp->tp_fund) {
case POINTER:
break;
case ERRONEOUS:
return;
default: /* unindexable */
switch (expr->ex_type->tp_fund) {
case POINTER:
break;
case ERRONEOUS:
return;
default:
expr_error(*expp,
"indexing an object of type %s",
symbol2str(expp_tp->tp_fund));
return;
}
break;
}
ch3bin(expp, '+', expr);
ch3mon('*', expp);
break;
case '(': /* 3.3.2.2 */
if (expp_tp->tp_fund == POINTER
&& expp_tp->tp_up->tp_fund == FUNCTION) {
ch3mon('*', expp);
expp_tp = (*expp)->ex_type;
}
if (expp_tp->tp_fund != FUNCTION) {
expr_error(*expp, "call of non-function (%s)",
symbol2str(expp_tp->tp_fund));
/* leave the expression; it may still serve */
free_expression(expr); /* there go the parameters */
*expp = new_oper(error_type,
*expp, '(', (struct expr *)0);
}
else
*expp = new_oper(expp_tp->tp_up, *expp, '(', expr);
(*expp)->ex_flags |= EX_SIDEEFFECTS;
break;
case PARCOMMA: /* 3.3.2.2 */
*expp = new_oper(expr->ex_type, *expp, PARCOMMA, expr);
break;
case '%':
case MODAB:
case ANDAB:
case XORAB:
case ORAB:
opnd2integral(expp, oper);
opnd2integral(&expr, oper);
/* fallthrough */
case '/':
case DIVAB:
case TIMESAB:
arithbalance(expp, oper, &expr);
non_commutative_binop(expp, oper, expr);
break;
case '&':
case '^':
case '|':
opnd2integral(expp, oper);
opnd2integral(&expr, oper);
/* fallthrough */
case '*':
arithbalance(expp, oper, &expr);
commutative_binop(expp, oper, expr);
break;
case '+':
if (expr->ex_type->tp_fund == POINTER) { /* swap operands */
struct expr *etmp = expr;
expp_tp = expr->ex_type; /* both in registers */
expr = *expp;
*expp = etmp;
}
/* fallthrough */
case PLUSAB:
case POSTINCR:
case PLUSPLUS:
if (expp_tp->tp_fund == POINTER) {
pointer_arithmetic(expp, oper, &expr);
if (expr->ex_type->tp_size != (*expp)->ex_type->tp_size)
ch3cast(&expr, CAST, (*expp)->ex_type);
pointer_binary(expp, oper, expr);
}
else {
arithbalance(expp, oper, &expr);
if (oper == '+')
commutative_binop(expp, oper, expr);
else
non_commutative_binop(expp, oper, expr);
}
break;
case '-':
case MINAB:
case POSTDECR:
case MINMIN:
if (expp_tp->tp_fund == POINTER) {
if (expr->ex_type->tp_fund == POINTER)
pntminuspnt(expp, oper, expr);
else {
pointer_arithmetic(expp, oper, &expr);
pointer_binary(expp, oper, expr);
}
}
else {
arithbalance(expp, oper, &expr);
non_commutative_binop(expp, oper, expr);
}
break;
case LEFT:
case RIGHT:
case LEFTAB:
case RIGHTAB:
opnd2integral(expp, oper);
opnd2integral(&expr, oper);
arithbalance(expp, oper, &expr); /* ch. 3.3.7 */
ch3cast(&expr, oper, int_type); /* cvt. rightop to int */
non_commutative_binop(expp, oper, expr);
break;
case '<':
case '>':
case LESSEQ:
case GREATEREQ:
case EQUAL:
case NOTEQUAL:
relbalance(expp, oper, &expr);
non_commutative_relop(expp, oper, expr);
(*expp)->ex_type = int_type;
break;
case AND:
case OR:
opnd2test(expp, oper);
opnd2test(&expr, oper);
if (is_cp_cst(*expp)) {
register struct expr *ex = *expp;
/* the following condition is a short-hand for
((oper == AND) && o1) || ((oper == OR) && !o1)
where o1 == (*expp)->VL_VALUE;
and ((oper == AND) || (oper == OR))
*/
if ((oper == AND) == (ex->VL_VALUE != 0)) {
*expp = expr;
}
else {
ex->ex_flags |= expr->ex_flags;
free_expression(expr);
*expp = intexpr((arith)(oper != AND), INT);
}
(*expp)->ex_flags |= ex->ex_flags | EX_ILVALUE;
free_expression(ex);
}
else
if (is_cp_cst(expr)) {
/* Note!!!: the following condition is a short-hand for
((oper == AND) && o2) || ((oper == OR) && !o2)
where o2 == expr->VL_VALUE
and ((oper == AND) || (oper == OR))
*/
if ((oper == AND) == (expr->VL_VALUE != 0)) {
(*expp)->ex_flags |= expr->ex_flags | EX_ILVALUE;
free_expression(expr);
}
else {
if (oper == OR)
expr->VL_VALUE = 1;
ch3bin(expp, ',', expr);
}
}
else {
*expp = new_oper(int_type, *expp, oper, expr);
}
(*expp)->ex_flags |= EX_LOGICAL;
break;
case ':':
if (is_struct_or_union(expp_tp->tp_fund)
|| is_struct_or_union(expr->ex_type->tp_fund)) {
if (!equal_type(expp_tp, expr->ex_type, -1, 0))
expr_error(*expp, "illegal balance");
}
else
relbalance(expp, oper, &expr);
#ifdef LINT
if ( (is_cp_cst(*expp) && is_cp_cst(expr))
&& (*expp)->VL_VALUE == expr->VL_VALUE
) {
hwarning("operands of : are constant and equal");
}
#endif /* LINT */
*expp = new_oper((*expp)->ex_type, *expp, oper, expr);
break;
case '?':
opnd2logical(expp, oper);
if (is_cp_cst(*expp)) {
#ifdef LINT
hwarning("condition in ?: expression is constant");
#endif /* LINT */
if ((*expp)->VL_VALUE) {
free_expression(*expp);
free_expression(expr->OP_RIGHT);
*expp = expr->OP_LEFT;
}
else {
free_expression(*expp);
free_expression(expr->OP_LEFT);
*expp = expr->OP_RIGHT;
}
free_expr(expr);
(*expp)->ex_flags |= EX_ILVALUE;
}
else {
*expp = new_oper(expr->ex_type, *expp, oper, expr);
}
break;
case ',':
if (is_cp_cst(*expp)) {
#ifdef LINT
hwarning("constant expression ignored");
#endif /* LINT */
free_expression(*expp);
*expp = expr;
}
else {
*expp = new_oper(expr->ex_type, *expp, oper, expr);
}
(*expp)->ex_flags |= EX_COMMA;
break;
}
}
void pntminuspnt(register struct expr **expp, int oper, register struct expr *expr)
{
/* Subtracting two pointers is so complicated it merits a
routine of its own.
*/
struct type *up_type = (*expp)->ex_type->tp_up;
if (!equal_type(up_type, expr->ex_type->tp_up, -1, 0)) {
expr_error(*expp, "subtracting incompatible pointers");
free_expression(expr);
erroneous2int(expp);
return;
}
/* we hope the optimizer will eliminate the load-time
pointer subtraction
*/
*expp = new_oper((*expp)->ex_type, *expp, oper, expr);
ch3cast(expp, CAST, pa_type); /* ptr-ptr: result has pa_type */
ch3bin(expp, '/'
, intexpr(size_of_type(up_type, symbol2str(up_type->tp_fund))
, pa_type->tp_fund));
ch3cast(expp, CAST, pa_type); /* result will be an integral expr */
/* cast necessary ??? */
if (int_size != pointer_size) (*expp)->ex_flags |= EX_PTRDIFF;
}
/*
* The function arg_switched() returns the operator that should be used
* when the arguments are switched. This is special for some relational
* operators.
*/
int arg_switched(int oper)
{
switch (oper) {
case '<': return '>';
case '>': return '<';
case LESSEQ: return GREATEREQ;
case GREATEREQ: return LESSEQ;
default: return oper;
}
}
void mk_binop(struct expr **expp, int oper, register struct expr *expr, int commutative)
{
/* Constructs in *expp the operation indicated by the operands.
"commutative" indicates whether "oper" is a commutative
operator.
*/
register struct expr *ex = *expp;
if (is_cp_cst(expr) && is_cp_cst(ex))
cstbin(expp, oper, expr);
else if (is_fp_cst(expr) && is_fp_cst(ex))
fltcstbin(expp, oper, expr);
else {
*expp = (commutative
&& !(ex->ex_flags & EX_VOLATILE)
&& (expr->ex_depth > ex->ex_depth
|| ((expr->ex_flags & EX_SIDEEFFECTS)
&& !(ex->ex_flags & EX_SIDEEFFECTS))
|| is_cp_cst(ex)))
? new_oper(ex->ex_type, expr, arg_switched(oper), ex)
: new_oper(ex->ex_type, ex, oper, expr);
}
}
void pointer_arithmetic(register struct expr **expp1, int oper, register struct expr **expp2)
{
int typ;
/* prepares the integral expression expp2 in order to
apply it to the pointer expression expp1
*/
if ((typ = any2arith(expp2, oper)) == FLOAT
|| typ == DOUBLE
|| typ == LNGDBL) {
expr_error(*expp2,
"illegal combination of %s and pointer",
symbol2str(typ));
erroneous2int(expp2);
}
ch3bin( expp2, '*',
intexpr(size_of_type((*expp1)->ex_type->tp_up, "object"),
pa_type->tp_fund)
);
}
void pointer_binary(register struct expr **expp, int oper, register struct expr *expr)
{
/* constructs the pointer arithmetic expression out of
a pointer expression, a binary operator and an integral
expression.
*/
if (is_ld_cst(expr) && is_ld_cst(*expp))
cstbin(expp, oper, expr);
else
*expp = new_oper((*expp)->ex_type, *expp, oper, expr);
}