cc65/src/ca65/expr.h

185 lines
7.2 KiB
C

/*****************************************************************************/
/* */
/* expr.h */
/* */
/* Expression evaluation for the ca65 macroassembler */
/* */
/* */
/* */
/* (C) 1998-2012, Ullrich von Bassewitz */
/* Roemerstrasse 52 */
/* D-70794 Filderstadt */
/* EMail: uz@cc65.org */
/* */
/* */
/* This software is provided 'as-is', without any expressed or implied */
/* warranty. In no event will the authors be held liable for any damages */
/* arising from the use of this software. */
/* */
/* Permission is granted to anyone to use this software for any purpose, */
/* including commercial applications, and to alter it and redistribute it */
/* freely, subject to the following restrictions: */
/* */
/* 1. The origin of this software must not be misrepresented; you must not */
/* claim that you wrote the original software. If you use this software */
/* in a product, an acknowledgment in the product documentation would be */
/* appreciated but is not required. */
/* 2. Altered source versions must be plainly marked as such, and must not */
/* be misrepresented as being the original software. */
/* 3. This notice may not be removed or altered from any source */
/* distribution. */
/* */
/*****************************************************************************/
#ifndef EXPR_H
#define EXPR_H
/* common */
#include "coll.h"
#include "exprdefs.h"
/*****************************************************************************/
/* Forwards */
/*****************************************************************************/
struct ExprDesc;
/*****************************************************************************/
/* Code */
/*****************************************************************************/
ExprNode* Expression (void);
/* Evaluate an expression, build the expression tree on the heap and return
** a pointer to the root of the tree.
*/
long ConstExpression (void);
/* Parse an expression. Check if the expression is const, and print an error
** message if not. Return the value of the expression, or a dummy, if it is
** not constant.
*/
void FreeExpr (ExprNode* Root);
/* Free the expression tree, Root is pointing to. */
ExprNode* SimplifyExpr (ExprNode* Expr, const struct ExprDesc* D);
/* Try to simplify the given expression tree */
ExprNode* GenLiteralExpr (long Val);
/* Return an expression tree that encodes the given literal value */
ExprNode* GenLiteral0 (void);
/* Return an expression tree that encodes the number zero */
ExprNode* GenSymExpr (struct SymEntry* Sym);
/* Return an expression node that encodes the given symbol */
ExprNode* GenAddExpr (ExprNode* Left, ExprNode* Right);
/* Generate an addition from the two operands */
ExprNode* GenCurrentPC (void);
/* Return the current program counter as expression */
ExprNode* GenSwapExpr (ExprNode* Expr);
/* Return an extended expression with lo and hi bytes swapped */
ExprNode* GenBranchExpr (unsigned Offs);
/* Return an expression that encodes the difference between current PC plus
** offset and the target expression (that is, Expression() - (*+Offs) ).
*/
ExprNode* GenULabelExpr (unsigned Num);
/* Return an expression for an unnamed label with the given index */
ExprNode* GenByteExpr (ExprNode* Expr);
/* Force the given expression into a byte and return the result */
ExprNode* GenWordExpr (ExprNode* Expr);
/* Force the given expression into a word and return the result. */
ExprNode* GenNearAddrExpr (ExprNode* Expr);
/* A word sized expression that will error if given a far expression at assemble time. */
ExprNode* GenFarAddrExpr (ExprNode* Expr);
/* Force the given expression into a far address and return the result. */
ExprNode* GenDWordExpr (ExprNode* Expr);
/* Force the given expression into a dword and return the result. */
ExprNode* GenNE (ExprNode* Expr, long Val);
/* Generate an expression that compares Expr and Val for inequality */
int IsConstExpr (ExprNode* Expr, long* Val);
/* Return true if the given expression is a constant expression, that is, one
** with no references to external symbols. If Val is not NULL and the
** expression is constant, the constant value is stored here.
*/
int IsByteExpr (ExprNode* Root);
/* Return true if this is a byte expression */
int IsByteRange (long Val);
/* Return true if this is a byte value */
int IsWordRange (long Val);
/* Return true if this is a word value */
int IsFarRange (long Val);
/* Return true if this is a far (24 bit) value */
int IsEasyConst (const ExprNode* E, long* Val);
/* Do some light checking if the given node is a constant. Don't care if E is
** a complex expression. If E is a constant, return true and place its value
** into Val, provided that Val is not NULL.
*/
ExprNode* CloneExpr (ExprNode* Expr);
/* Clone the given expression tree. The function will simply clone symbol
** nodes, it will not resolve them.
*/
void WriteExpr (ExprNode* Expr);
/* Write the given expression to the object file */
void ExprGuessedAddrSize (const ExprNode* Expr, unsigned char AddrSize);
/* Mark the address size of the given expression tree as guessed. The address
** size passed as argument is the one NOT used, because the actual address
** size wasn't known. Example: Zero page addressing was not used because symbol
** is undefined, and absolute addressing was available.
** This function will actually parse the expression tree for undefined symbols,
** and mark these symbols accordingly.
*/
ExprNode* FuncBankByte (void);
/* Handle the .BANKBYTE builtin function */
ExprNode* FuncLoByte (void);
/* Handle the .LOBYTE builtin function */
ExprNode* FuncHiByte (void);
/* Handle the .HIBYTE builtin function */
ExprNode* MakeBoundedExpr (ExprNode* Expr, unsigned Size);
/* Force the given expression into a specific size of ForceRange is true */
ExprNode* BoundedExpr (ExprNode* (*ExprFunc) (void), unsigned Size);
/* Parse an expression and force it within a given size if ForceRange is true */
/* End of expr.h */
#endif