106 lines
3 KiB
Text
106 lines
3 KiB
Text
/* $Header$ */
|
|
/* EXPRESSION DESCRIPTOR */
|
|
|
|
/* What we want to define is the struct expr, but since it contains
|
|
a union of various goodies, we define them first; so be patient.
|
|
*/
|
|
|
|
#include "nofloat.h"
|
|
|
|
/* classes of value */
|
|
#define Const 1
|
|
#define Name 2
|
|
#define Label 3
|
|
|
|
struct value {
|
|
int vl_class; /* Const, Name or Label */
|
|
arith vl_value; /* constant value or offset */
|
|
union {
|
|
struct idf *vl_idf; /* external name */
|
|
label vl_lbl; /* compiler-generated label */
|
|
} vl_data;
|
|
};
|
|
|
|
struct string {
|
|
char *sg_value; /* row of bytes repr. the constant */
|
|
int sg_len; /* length of the row */
|
|
label sg_datlab; /* global data-label */
|
|
};
|
|
|
|
#ifndef NOFLOAT
|
|
struct floating {
|
|
char *fl_value; /* pointer to string repr. the fp const. */
|
|
label fl_datlab; /* global data_label */
|
|
};
|
|
#endif NOFLOAT
|
|
|
|
struct oper {
|
|
struct type *op_type; /* resulting type of the operation */
|
|
struct expr *op_left;
|
|
int op_oper; /* the symbol of the operator */
|
|
struct expr *op_right;
|
|
};
|
|
|
|
/* The following constants indicate the class of the expression: */
|
|
#define Value 0 /* it is a value known at load time */
|
|
#define String 1 /* it is a string constant */
|
|
#ifndef NOFLOAT
|
|
#define Float 2 /* it is a floating point constant */
|
|
#endif NOFLOAT
|
|
#define Oper 3 /* it is a run-time expression */
|
|
#define Type 4 /* only its type is relevant */
|
|
|
|
struct expr {
|
|
struct expr *next;
|
|
char *ex_file; /* the file it (probably) comes from */
|
|
unsigned int ex_line; /* the line it (probably) comes from */
|
|
struct type *ex_type;
|
|
char ex_lvalue;
|
|
char ex_flags;
|
|
int ex_class;
|
|
int ex_depth;
|
|
union {
|
|
struct value ex_value;
|
|
struct string ex_string;
|
|
#ifndef NOFLOAT
|
|
struct floating ex_float;
|
|
#endif NOFLOAT
|
|
struct oper ex_oper;
|
|
} ex_object;
|
|
};
|
|
|
|
/* some abbreviated selections */
|
|
#define VL_CLASS ex_object.ex_value.vl_class
|
|
#define VL_VALUE ex_object.ex_value.vl_value
|
|
#define VL_IDF ex_object.ex_value.vl_data.vl_idf
|
|
#define VL_LBL ex_object.ex_value.vl_data.vl_lbl
|
|
#define SG_VALUE ex_object.ex_string.sg_value
|
|
#define SG_LEN ex_object.ex_string.sg_len
|
|
#define SG_DATLAB ex_object.ex_string.sg_datlab
|
|
#ifndef NOFLOAT
|
|
#define FL_VALUE ex_object.ex_float.fl_value
|
|
#define FL_DATLAB ex_object.ex_float.fl_datlab
|
|
#endif NOFLOAT
|
|
#define OP_TYPE ex_object.ex_oper.op_type
|
|
#define OP_LEFT ex_object.ex_oper.op_left
|
|
#define OP_OPER ex_object.ex_oper.op_oper
|
|
#define OP_RIGHT ex_object.ex_oper.op_right
|
|
|
|
/* some bits for the ex_flag field, to keep track of various
|
|
interesting properties of an expression.
|
|
*/
|
|
#define EX_SIZEOF 0001 /* contains sizeof operator */
|
|
#define EX_CAST 0002 /* contains cast */
|
|
#define EX_LOGICAL 0004 /* contains logical operator */
|
|
#define EX_COMMA 0010 /* contains expression comma */
|
|
#define EX_PARENS 0020 /* the top level is parenthesized */
|
|
#define EX_SIDEEFFECTS 0040 /* expression has side effects */
|
|
#define EX_ERROR 0200 /* the expression is wrong */
|
|
|
|
#define NILEXPR ((struct expr *)0)
|
|
|
|
extern struct expr *intexpr(), *new_oper();
|
|
|
|
/* ALLOCDEF "expr" 50 */
|
|
|
|
#define ISCOMMA(e) ((e)->ex_class == Oper && (e)->OP_OPER == INITCOMMA)
|