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) {}
46 bool EvaluateAsRelocatableImpl(MCValue &Res, const MCAsmLayout *Layout,
52 ExprKind getKind() const { return Kind; }
55 /// @name Utility Methods
58 void print(raw_ostream &OS) const;
62 /// @name Expression Evaluation
65 /// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value.
67 /// @param Res - The absolute value, if evaluation succeeds.
68 /// @param Layout - The assembler layout object to use for evaluating symbol
69 /// values. If not given, then only non-symbolic expressions will be
71 /// @result - True on success.
72 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout *Layout = 0) const;
74 /// EvaluateAsRelocatable - Try to evaluate the expression to a relocatable
75 /// value, i.e. an expression of the fixed form (a - b + constant).
77 /// @param Res - The relocatable value, if evaluation succeeds.
78 /// @param Layout - The assembler layout object to use for evaluating values.
79 /// @result - True on success.
80 bool EvaluateAsRelocatable(MCValue &Res, const MCAsmLayout *Layout = 0) const;
84 static bool classof(const MCExpr *) { return true; }
87 inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) {
92 //// MCConstantExpr - Represent a constant integer expression.
93 class MCConstantExpr : public MCExpr {
96 explicit MCConstantExpr(int64_t _Value)
97 : MCExpr(MCExpr::Constant), Value(_Value) {}
100 /// @name Construction
103 static const MCConstantExpr *Create(int64_t Value, MCContext &Ctx);
109 int64_t getValue() const { return Value; }
113 static bool classof(const MCExpr *E) {
114 return E->getKind() == MCExpr::Constant;
116 static bool classof(const MCConstantExpr *) { return true; }
119 /// MCSymbolRefExpr - Represent a reference to a symbol from inside an
122 /// A symbol reference in an expression may be a use of a label, a use of an
123 /// assembler variable (defined constant), or constitute an implicit definition
124 /// of the symbol as external.
125 class MCSymbolRefExpr : public MCExpr {
143 VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the asm file)
144 VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the asm file)
145 VK_ARM_PLT, // ARM-style PLT symbol references. i.e., (PLT) instead of @PLT
146 VK_TLVP // Mach-O thread local variable relocation
150 /// The symbol being referenced.
151 const MCSymbol *Symbol;
153 /// The symbol reference modifier.
154 const VariantKind Kind;
156 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
157 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
160 /// @name Construction
163 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
164 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
167 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
169 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
176 const MCSymbol &getSymbol() const { return *Symbol; }
178 VariantKind getKind() const { return Kind; }
181 /// @name Static Utility Functions
184 static StringRef getVariantKindName(VariantKind Kind);
186 static VariantKind getVariantKindForName(StringRef Name);
190 static bool classof(const MCExpr *E) {
191 return E->getKind() == MCExpr::SymbolRef;
193 static bool classof(const MCSymbolRefExpr *) { return true; }
196 /// MCUnaryExpr - Unary assembler expressions.
197 class MCUnaryExpr : public MCExpr {
200 LNot, ///< Logical negation.
201 Minus, ///< Unary minus.
202 Not, ///< Bitwise negation.
203 Plus ///< Unary plus.
210 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
211 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
214 /// @name Construction
217 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
219 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
220 return Create(LNot, Expr, Ctx);
222 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
223 return Create(Minus, Expr, Ctx);
225 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
226 return Create(Not, Expr, Ctx);
228 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
229 return Create(Plus, Expr, Ctx);
236 /// getOpcode - Get the kind of this unary expression.
237 Opcode getOpcode() const { return Op; }
239 /// getSubExpr - Get the child of this unary expression.
240 const MCExpr *getSubExpr() const { return Expr; }
244 static bool classof(const MCExpr *E) {
245 return E->getKind() == MCExpr::Unary;
247 static bool classof(const MCUnaryExpr *) { return true; }
250 /// MCBinaryExpr - Binary assembler expressions.
251 class MCBinaryExpr : public MCExpr {
255 And, ///< Bitwise and.
256 Div, ///< Signed division.
257 EQ, ///< Equality comparison.
258 GT, ///< Signed greater than comparison (result is either 0 or some
259 ///< target-specific non-zero value)
260 GTE, ///< Signed greater than or equal comparison (result is either 0 or
261 ///< some target-specific non-zero value).
262 LAnd, ///< Logical and.
263 LOr, ///< Logical or.
264 LT, ///< Signed less than comparison (result is either 0 or
265 ///< some target-specific non-zero value).
266 LTE, ///< Signed less than or equal comparison (result is either 0 or
267 ///< some target-specific non-zero value).
268 Mod, ///< Signed remainder.
269 Mul, ///< Multiplication.
270 NE, ///< Inequality comparison.
272 Shl, ///< Shift left.
273 Shr, ///< Shift right (arithmetic or logical, depending on target)
274 Sub, ///< Subtraction.
275 Xor ///< Bitwise exclusive or.
280 const MCExpr *LHS, *RHS;
282 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
283 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
286 /// @name Construction
289 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
290 const MCExpr *RHS, MCContext &Ctx);
291 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
293 return Create(Add, LHS, RHS, Ctx);
295 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
297 return Create(And, LHS, RHS, Ctx);
299 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
301 return Create(Div, LHS, RHS, Ctx);
303 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
305 return Create(EQ, LHS, RHS, Ctx);
307 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
309 return Create(GT, LHS, RHS, Ctx);
311 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
313 return Create(GTE, LHS, RHS, Ctx);
315 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
317 return Create(LAnd, LHS, RHS, Ctx);
319 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
321 return Create(LOr, LHS, RHS, Ctx);
323 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
325 return Create(LT, LHS, RHS, Ctx);
327 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
329 return Create(LTE, LHS, RHS, Ctx);
331 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
333 return Create(Mod, LHS, RHS, Ctx);
335 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
337 return Create(Mul, LHS, RHS, Ctx);
339 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
341 return Create(NE, LHS, RHS, Ctx);
343 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
345 return Create(Or, LHS, RHS, Ctx);
347 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
349 return Create(Shl, LHS, RHS, Ctx);
351 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
353 return Create(Shr, LHS, RHS, Ctx);
355 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
357 return Create(Sub, LHS, RHS, Ctx);
359 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
361 return Create(Xor, LHS, RHS, Ctx);
368 /// getOpcode - Get the kind of this binary expression.
369 Opcode getOpcode() const { return Op; }
371 /// getLHS - Get the left-hand side expression of the binary operator.
372 const MCExpr *getLHS() const { return LHS; }
374 /// getRHS - Get the right-hand side expression of the binary operator.
375 const MCExpr *getRHS() const { return RHS; }
379 static bool classof(const MCExpr *E) {
380 return E->getKind() == MCExpr::Binary;
382 static bool classof(const MCBinaryExpr *) { return true; }
385 /// MCTargetExpr - This is an extension point for target-specific MCExpr
386 /// subclasses to implement.
388 /// NOTE: All subclasses are required to have trivial destructors because
389 /// MCExprs are bump pointer allocated and not destructed.
390 class MCTargetExpr : public MCExpr {
391 virtual void Anchor();
393 MCTargetExpr() : MCExpr(Target) {}
394 virtual ~MCTargetExpr() {}
397 virtual void PrintImpl(raw_ostream &OS) const = 0;
398 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
399 const MCAsmLayout *Layout) const = 0;
402 static bool classof(const MCExpr *E) {
403 return E->getKind() == MCExpr::Target;
405 static bool classof(const MCTargetExpr *) { return true; }
408 } // end namespace llvm