1 //===- MCExpr.h - Assembly Level Expressions --------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLVM_MC_MCEXPR_H
11 #define LLVM_MC_MCEXPR_H
13 #include "llvm/Support/Casting.h"
14 #include "llvm/System/DataTypes.h"
24 /// MCExpr - Base class for the full range of assembler expressions which are
25 /// needed for parsing.
29 Binary, ///< Binary expressions.
30 Constant, ///< Constant expressions.
31 SymbolRef, ///< References to labels and assigned expressions.
32 Unary, ///< Unary expressions.
33 Target ///< Target specific expression.
39 MCExpr(const MCExpr&); // DO NOT IMPLEMENT
40 void operator=(const MCExpr&); // DO NOT IMPLEMENT
43 explicit MCExpr(ExprKind _Kind) : Kind(_Kind) {}
49 ExprKind getKind() const { return Kind; }
52 /// @name Utility Methods
55 void print(raw_ostream &OS) const;
59 /// @name Expression Evaluation
62 /// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value.
64 /// @param Res - The absolute value, if evaluation succeeds.
65 /// @result - True on success.
66 bool EvaluateAsAbsolute(int64_t &Res) const;
68 /// EvaluateAsRelocatable - Try to evaluate the expression to a relocatable
69 /// value, i.e. an expression of the fixed form (a - b + constant).
71 /// @param Res - The relocatable value, if evaluation succeeds.
72 /// @result - True on success.
73 bool EvaluateAsRelocatable(MCValue &Res) const;
77 static bool classof(const MCExpr *) { return true; }
80 inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) {
85 //// MCConstantExpr - Represent a constant integer expression.
86 class MCConstantExpr : public MCExpr {
89 explicit MCConstantExpr(int64_t _Value)
90 : MCExpr(MCExpr::Constant), Value(_Value) {}
93 /// @name Construction
96 static const MCConstantExpr *Create(int64_t Value, MCContext &Ctx);
102 int64_t getValue() const { return Value; }
106 static bool classof(const MCExpr *E) {
107 return E->getKind() == MCExpr::Constant;
109 static bool classof(const MCConstantExpr *) { return true; }
112 /// MCSymbolRefExpr - Represent a reference to a symbol from inside an
115 /// A symbol reference in an expression may be a use of a label, a use of an
116 /// assembler variable (defined constant), or constitute an implicit definition
117 /// of the symbol as external.
118 class MCSymbolRefExpr : public MCExpr {
119 const MCSymbol *Symbol;
121 explicit MCSymbolRefExpr(const MCSymbol *_Symbol)
122 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol) {}
125 /// @name Construction
128 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx);
129 static const MCSymbolRefExpr *Create(StringRef Name, MCContext &Ctx);
131 /// CreateTemp - Create a reference to an assembler temporary label with the
133 static const MCSymbolRefExpr *CreateTemp(StringRef Name, MCContext &Ctx);
139 const MCSymbol &getSymbol() const { return *Symbol; }
143 static bool classof(const MCExpr *E) {
144 return E->getKind() == MCExpr::SymbolRef;
146 static bool classof(const MCSymbolRefExpr *) { return true; }
149 /// MCUnaryExpr - Unary assembler expressions.
150 class MCUnaryExpr : public MCExpr {
153 LNot, ///< Logical negation.
154 Minus, ///< Unary minus.
155 Not, ///< Bitwise negation.
156 Plus ///< Unary plus.
163 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
164 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
167 /// @name Construction
170 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
172 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
173 return Create(LNot, Expr, Ctx);
175 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
176 return Create(Minus, Expr, Ctx);
178 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
179 return Create(Not, Expr, Ctx);
181 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
182 return Create(Plus, Expr, Ctx);
189 /// getOpcode - Get the kind of this unary expression.
190 Opcode getOpcode() const { return Op; }
192 /// getSubExpr - Get the child of this unary expression.
193 const MCExpr *getSubExpr() const { return Expr; }
197 static bool classof(const MCExpr *E) {
198 return E->getKind() == MCExpr::Unary;
200 static bool classof(const MCUnaryExpr *) { return true; }
203 /// MCBinaryExpr - Binary assembler expressions.
204 class MCBinaryExpr : public MCExpr {
208 And, ///< Bitwise and.
209 Div, ///< Signed division.
210 EQ, ///< Equality comparison.
211 GT, ///< Signed greater than comparison (result is either 0 or some
212 ///< target-specific non-zero value)
213 GTE, ///< Signed greater than or equal comparison (result is either 0 or
214 ///< some target-specific non-zero value).
215 LAnd, ///< Logical and.
216 LOr, ///< Logical or.
217 LT, ///< Signed less than comparison (result is either 0 or
218 ///< some target-specific non-zero value).
219 LTE, ///< Signed less than or equal comparison (result is either 0 or
220 ///< some target-specific non-zero value).
221 Mod, ///< Signed remainder.
222 Mul, ///< Multiplication.
223 NE, ///< Inequality comparison.
225 Shl, ///< Shift left.
226 Shr, ///< Shift right (arithmetic or logical, depending on target)
227 Sub, ///< Subtraction.
228 Xor ///< Bitwise exclusive or.
233 const MCExpr *LHS, *RHS;
235 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
236 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
239 /// @name Construction
242 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
243 const MCExpr *RHS, MCContext &Ctx);
244 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
246 return Create(Add, LHS, RHS, Ctx);
248 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
250 return Create(And, LHS, RHS, Ctx);
252 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
254 return Create(Div, LHS, RHS, Ctx);
256 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
258 return Create(EQ, LHS, RHS, Ctx);
260 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
262 return Create(GT, LHS, RHS, Ctx);
264 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
266 return Create(GTE, LHS, RHS, Ctx);
268 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
270 return Create(LAnd, LHS, RHS, Ctx);
272 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
274 return Create(LOr, LHS, RHS, Ctx);
276 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
278 return Create(LT, LHS, RHS, Ctx);
280 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
282 return Create(LTE, LHS, RHS, Ctx);
284 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
286 return Create(Mod, LHS, RHS, Ctx);
288 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
290 return Create(Mul, LHS, RHS, Ctx);
292 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
294 return Create(NE, LHS, RHS, Ctx);
296 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
298 return Create(Or, LHS, RHS, Ctx);
300 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
302 return Create(Shl, LHS, RHS, Ctx);
304 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
306 return Create(Shr, LHS, RHS, Ctx);
308 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
310 return Create(Sub, LHS, RHS, Ctx);
312 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
314 return Create(Xor, LHS, RHS, Ctx);
321 /// getOpcode - Get the kind of this binary expression.
322 Opcode getOpcode() const { return Op; }
324 /// getLHS - Get the left-hand side expression of the binary operator.
325 const MCExpr *getLHS() const { return LHS; }
327 /// getRHS - Get the right-hand side expression of the binary operator.
328 const MCExpr *getRHS() const { return RHS; }
332 static bool classof(const MCExpr *E) {
333 return E->getKind() == MCExpr::Binary;
335 static bool classof(const MCBinaryExpr *) { return true; }
338 /// MCTargetExpr - This is an extension point for target-specific MCExpr
339 /// subclasses to implement.
341 /// NOTE: All subclasses are required to have trivial destructors because
342 /// MCExprs are bump pointer allocated and not destructed.
343 class MCTargetExpr : public MCExpr {
344 virtual void Anchor();
346 MCTargetExpr() : MCExpr(Target) {}
347 virtual ~MCTargetExpr() {}
350 virtual void PrintImpl(raw_ostream &OS) const = 0;
351 virtual bool EvaluateAsRelocatableImpl(MCValue &Res) const = 0;
354 static bool classof(const MCExpr *E) {
355 return E->getKind() == MCExpr::Target;
357 static bool classof(const MCTargetExpr *) { return true; }
360 } // end namespace llvm