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"
25 /// MCExpr - Base class for the full range of assembler expressions which are
26 /// needed for parsing.
30 Binary, ///< Binary expressions.
31 Constant, ///< Constant expressions.
32 SymbolRef, ///< References to labels and assigned expressions.
33 Unary, ///< Unary expressions.
34 Target ///< Target specific expression.
40 MCExpr(const MCExpr&); // DO NOT IMPLEMENT
41 void operator=(const MCExpr&); // DO NOT IMPLEMENT
44 explicit MCExpr(ExprKind _Kind) : Kind(_Kind) {}
50 ExprKind getKind() const { return Kind; }
53 /// @name Utility Methods
56 void print(raw_ostream &OS) const;
60 /// @name Expression Evaluation
63 /// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value.
65 /// @param Res - The absolute value, if evaluation succeeds.
66 /// @param Layout - The assembler layout object to use for evaluating symbol
67 /// values. If not given, then only non-symbolic expressions will be
69 /// @result - True on success.
70 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout *Layout = 0) const;
72 /// EvaluateAsRelocatable - Try to evaluate the expression to a relocatable
73 /// value, i.e. an expression of the fixed form (a - b + constant).
75 /// @param Res - The relocatable value, if evaluation succeeds.
76 /// @param Layout - The assembler layout object to use for evaluating values.
77 /// @result - True on success.
78 bool EvaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout = 0) const;
82 static bool classof(const MCExpr *) { return true; }
85 inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) {
90 //// MCConstantExpr - Represent a constant integer expression.
91 class MCConstantExpr : public MCExpr {
94 explicit MCConstantExpr(int64_t _Value)
95 : MCExpr(MCExpr::Constant), Value(_Value) {}
98 /// @name Construction
101 static const MCConstantExpr *Create(int64_t Value, MCContext &Ctx);
107 int64_t getValue() const { return Value; }
111 static bool classof(const MCExpr *E) {
112 return E->getKind() == MCExpr::Constant;
114 static bool classof(const MCConstantExpr *) { return true; }
117 /// MCSymbolRefExpr - Represent a reference to a symbol from inside an
120 /// A symbol reference in an expression may be a use of a label, a use of an
121 /// assembler variable (defined constant), or constitute an implicit definition
122 /// of the symbol as external.
123 class MCSymbolRefExpr : public MCExpr {
138 VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the asm file)
139 VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the asm file)
140 VK_TLVP // Mach-O thread local variable relocation
144 /// The symbol being referenced.
145 const MCSymbol *Symbol;
147 /// The symbol reference modifier.
148 const VariantKind Kind;
150 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
151 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
154 /// @name Construction
157 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
158 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
161 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
163 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
170 const MCSymbol &getSymbol() const { return *Symbol; }
172 VariantKind getKind() const { return Kind; }
175 /// @name Static Utility Functions
178 static StringRef getVariantKindName(VariantKind Kind);
180 static VariantKind getVariantKindForName(StringRef Name);
184 static bool classof(const MCExpr *E) {
185 return E->getKind() == MCExpr::SymbolRef;
187 static bool classof(const MCSymbolRefExpr *) { return true; }
190 /// MCUnaryExpr - Unary assembler expressions.
191 class MCUnaryExpr : public MCExpr {
194 LNot, ///< Logical negation.
195 Minus, ///< Unary minus.
196 Not, ///< Bitwise negation.
197 Plus ///< Unary plus.
204 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
205 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
208 /// @name Construction
211 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
213 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
214 return Create(LNot, Expr, Ctx);
216 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
217 return Create(Minus, Expr, Ctx);
219 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
220 return Create(Not, Expr, Ctx);
222 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
223 return Create(Plus, Expr, Ctx);
230 /// getOpcode - Get the kind of this unary expression.
231 Opcode getOpcode() const { return Op; }
233 /// getSubExpr - Get the child of this unary expression.
234 const MCExpr *getSubExpr() const { return Expr; }
238 static bool classof(const MCExpr *E) {
239 return E->getKind() == MCExpr::Unary;
241 static bool classof(const MCUnaryExpr *) { return true; }
244 /// MCBinaryExpr - Binary assembler expressions.
245 class MCBinaryExpr : public MCExpr {
249 And, ///< Bitwise and.
250 Div, ///< Signed division.
251 EQ, ///< Equality comparison.
252 GT, ///< Signed greater than comparison (result is either 0 or some
253 ///< target-specific non-zero value)
254 GTE, ///< Signed greater than or equal comparison (result is either 0 or
255 ///< some target-specific non-zero value).
256 LAnd, ///< Logical and.
257 LOr, ///< Logical or.
258 LT, ///< Signed less than comparison (result is either 0 or
259 ///< some target-specific non-zero value).
260 LTE, ///< Signed less than or equal comparison (result is either 0 or
261 ///< some target-specific non-zero value).
262 Mod, ///< Signed remainder.
263 Mul, ///< Multiplication.
264 NE, ///< Inequality comparison.
266 Shl, ///< Shift left.
267 Shr, ///< Shift right (arithmetic or logical, depending on target)
268 Sub, ///< Subtraction.
269 Xor ///< Bitwise exclusive or.
274 const MCExpr *LHS, *RHS;
276 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
277 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
280 /// @name Construction
283 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
284 const MCExpr *RHS, MCContext &Ctx);
285 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
287 return Create(Add, LHS, RHS, Ctx);
289 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
291 return Create(And, LHS, RHS, Ctx);
293 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
295 return Create(Div, LHS, RHS, Ctx);
297 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
299 return Create(EQ, LHS, RHS, Ctx);
301 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
303 return Create(GT, LHS, RHS, Ctx);
305 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
307 return Create(GTE, LHS, RHS, Ctx);
309 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
311 return Create(LAnd, LHS, RHS, Ctx);
313 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
315 return Create(LOr, LHS, RHS, Ctx);
317 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
319 return Create(LT, LHS, RHS, Ctx);
321 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
323 return Create(LTE, LHS, RHS, Ctx);
325 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
327 return Create(Mod, LHS, RHS, Ctx);
329 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
331 return Create(Mul, LHS, RHS, Ctx);
333 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
335 return Create(NE, LHS, RHS, Ctx);
337 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
339 return Create(Or, LHS, RHS, Ctx);
341 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
343 return Create(Shl, LHS, RHS, Ctx);
345 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
347 return Create(Shr, LHS, RHS, Ctx);
349 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
351 return Create(Sub, LHS, RHS, Ctx);
353 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
355 return Create(Xor, LHS, RHS, Ctx);
362 /// getOpcode - Get the kind of this binary expression.
363 Opcode getOpcode() const { return Op; }
365 /// getLHS - Get the left-hand side expression of the binary operator.
366 const MCExpr *getLHS() const { return LHS; }
368 /// getRHS - Get the right-hand side expression of the binary operator.
369 const MCExpr *getRHS() const { return RHS; }
373 static bool classof(const MCExpr *E) {
374 return E->getKind() == MCExpr::Binary;
376 static bool classof(const MCBinaryExpr *) { return true; }
379 /// MCTargetExpr - This is an extension point for target-specific MCExpr
380 /// subclasses to implement.
382 /// NOTE: All subclasses are required to have trivial destructors because
383 /// MCExprs are bump pointer allocated and not destructed.
384 class MCTargetExpr : public MCExpr {
385 virtual void Anchor();
387 MCTargetExpr() : MCExpr(Target) {}
388 virtual ~MCTargetExpr() {}
391 virtual void PrintImpl(raw_ostream &OS) const = 0;
392 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
393 const MCAsmLayout *Layout) const = 0;
396 static bool classof(const MCExpr *E) {
397 return E->getKind() == MCExpr::Target;
399 static bool classof(const MCTargetExpr *) { return true; }
402 } // end namespace llvm