MultiSource/Benchmarks/MallocBench/gs/zarith.c

/* Copyright (C) 1989, 1990 Aladdin Enterprises.  All rights reserved.
   Distributed by Free Software Foundation, Inc.

This file is part of Ghostscript.

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to the Ghostscript General Public License for full details.

Everyone is granted permission to copy, modify and redistribute
Ghostscript, but only under the conditions described in the Ghostscript
General Public License.  A copy of this license is supposed to have been
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responsibilities.  It should be in a file named COPYING.  Among other
things, the copyright notice and this notice must be preserved on all
copies.  */

/* zarith.c */
/* Arithmetic operators for GhostScript */
#include "math_.h"
#include "ghost.h"
#include "errors.h"
#include "oper.h"
#include "store.h"

/****** NOTE: none of the arithmetic operators  ******/
/****** currently check for floating exceptions ******/

/* Macro for accessing next-to-top stack element */
#define opm1 (op-1)
/* Macros for generating non-integer cases for arithmetic operations. */
/* 'frob' is one of the arithmetic operators, +, -, or *. */
#define non_int_cases(frob,frob_equals)\
 switch ( r_type(op) ) {\
  default: return e_typecheck;\
  case t_real: switch ( r_type(opm1) ) {\
   default: return e_typecheck;\
   case t_real: opm1->value.realval frob_equals op->value.realval; break;\
   case t_integer: make_real(opm1, opm1->value.intval frob op->value.realval);\
  } break;\
  case t_integer: switch ( r_type(opm1) ) {\
   default: return e_typecheck;\
   case t_real: opm1->value.realval frob_equals op->value.intval; break;\
   case t_integer:
#define end_cases()\
  } }

/* add */
int
zadd(register ref *op)
{	non_int_cases(+, +=)
	   {	long int2 = op->value.intval;
		if ( ((opm1->value.intval += int2) ^ int2) < 0 &&
		     ((opm1->value.intval - int2) ^ int2) >= 0
		   )
		   {	/* Overflow, convert to real */
			make_real(opm1, (float)opm1->value.intval - int2);
		   }
	   }
	end_cases()
	pop(1);
	return 0;
}

/* div */
int
zdiv(register ref *op)
{	register ref *op1 = op - 1;
	/* We can't use the non_int_cases macro, */
	/* because we have to check explicitly for op == 0. */
	switch ( r_type(op) )
	   {
	default: return e_typecheck;
	case t_real:
		if ( op->value.realval == 0 ) return e_undefinedresult;
		switch ( r_type(op1) )
		   {
		default: return e_typecheck;
		case t_real: op1->value.realval /= op->value.realval; break;
		case t_integer: make_real(op1, op1->value.intval / op->value.realval);
		   }
		break;
	case t_integer:
		if ( op->value.intval == 0 ) return e_undefinedresult;
		switch ( r_type(op1) )
		   {
		default: return e_typecheck;
		case t_real: op1->value.realval /= op->value.intval; break;
		case t_integer: make_real(op1, (float)op1->value.intval / op->value.intval);
		   }
	   }
	pop(1);
	return 0;
}

/* mul */
int
zmul(register ref *op)
{	non_int_cases(*, *=)
	   {	long int1 = opm1->value.intval;
		long int2 = op->value.intval;
		long abs1 = (int1 >= 0 ? int1 : - int1);
		long abs2 = (int2 >= 0 ? int2 : - int2);
		float fprod;
		if (	(abs1 > 0x7fff || abs2 > 0x7fff) &&
			/* At least one of the operands is very large. */
			/* Check for integer overflow. */
			abs1 != 0 &&
			abs2 > 0x7fffffffL / abs1 &&
			/* Check for the boundary case */
			(fprod = (float)int1 * int2,
			 (int1 * int2 != -0x80000000L ||
			 fprod != (float)-0x80000000L))
		   )
			make_real(opm1, fprod);
		else
			opm1->value.intval = int1 * int2;
	   }
	end_cases()
	pop(1);
	return 0;
}

/* sub */
int
zsub(register ref *op)
{	non_int_cases(-, -=)
	   {	long int1 = opm1->value.intval;
		if ( (int1 ^ (opm1->value.intval = int1 - op->value.intval)) < 0 &&
		     (int1 ^ op->value.intval) < 0
		   )
		   {	/* Overflow, convert to real */
			make_real(opm1, (float)int1 - op->value.intval);
		   }
	   }
	end_cases()
	pop(1);
	return 0;
}

/* idiv */
int
zidiv(register ref *op)
{	/* The Red Book says this only works on integers, */
	/* but implementations also accept reals. */
	ref save_num;
	int code;
	save_num = op[-1];
	code = zdiv(op);
	if ( code < 0 ) return code;	/* division failed */
	code = zcvi(op - 1);
	if ( code < 0 )
	   {	/* cvi failed, restore numerator */
		op[-1] = save_num;
		osp = op;		/* restore osp as well */
	   }
	return code;
}

/* mod */
int
zmod(register ref *op)
{	check_type(op[-1], t_integer);
	check_type(*op, t_integer);
	if ( op->value.intval == 0 ) return e_undefinedresult;
	op[-1].value.intval %= op->value.intval;
	pop(1);
	return 0;
}

/* neg */
int
zneg(register ref *op)
{	switch ( r_type(op) )
	   {
	default: return e_typecheck;
	case t_real: op->value.realval = -op->value.realval; break;
	case t_integer:
		if ( op->value.intval == -0x80000000L )	/* min integer */
			make_real(op, -(float)-0x80000000L);
		else
			op->value.intval = -op->value.intval;
	   }
	return 0;
}

/* ceiling */
int
zceiling(register ref *op)
{	switch ( r_type(op) )
	   {
	default: return e_typecheck;
	case t_real: op->value.realval = ceil(op->value.realval);
	case t_integer: ;
	   }
	return 0;
}

/* floor */
int
zfloor(register ref *op)
{	switch ( r_type(op) )
	   {
	default: return e_typecheck;
	case t_real: op->value.realval = floor(op->value.realval);
	case t_integer: ;
	   }
	return 0;
}

/* round */
int
zround(register ref *op)
{	switch ( r_type(op) )
	   {
	default: return e_typecheck;
	case t_real: op->value.realval = floor(op->value.realval + 0.5);
	case t_integer: ;
	   }
	return 0;
}

/* truncate */
int
ztruncate(register ref *op)
{	switch ( r_type(op) )
	   {
	default: return e_typecheck;
	case t_real:
		op->value.realval =
			(op->value.realval < 0.0 ?
				ceil(op->value.realval) :
				floor(op->value.realval));
	case t_integer: ;
	   }
	return 0;
}

/* ------ Initialization procedure ------ */

void
zarith_op_init()
{	static op_def my_defs[] = {
		{"2add", zadd},
		{"1ceiling", zceiling},
		{"2div", zdiv},
		{"2idiv", zidiv},
		{"1floor", zfloor},
		{"2mod", zmod},
		{"2mul", zmul},
		{"1neg", zneg},
		{"1round", zround},
		{"2sub", zsub},
		{"1truncate", ztruncate},
		op_def_end
	};
	z_op_init(my_defs);
}