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/Support/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 {
144 VK_TLVP, // Mach-O thread local variable relocation
145 VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the .s file)
146 VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the .w file)
147 // FIXME: We'd really like to use the generic Kinds listed above for these.
148 VK_ARM_PLT, // ARM-style PLT references. i.e., (PLT) instead of @PLT
149 VK_ARM_TLSGD, // ditto for TLSGD, GOT, GOTOFF, TPOFF and GOTTPOFF
156 VK_PPC_HA16, // ha16(symbol)
157 VK_PPC_LO16 // lo16(symbol)
161 /// The symbol being referenced.
162 const MCSymbol *Symbol;
164 /// The symbol reference modifier.
165 const VariantKind Kind;
167 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
168 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
171 /// @name Construction
174 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
175 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
178 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
180 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
187 const MCSymbol &getSymbol() const { return *Symbol; }
189 VariantKind getKind() const { return Kind; }
192 /// @name Static Utility Functions
195 static StringRef getVariantKindName(VariantKind Kind);
197 static VariantKind getVariantKindForName(StringRef Name);
201 static bool classof(const MCExpr *E) {
202 return E->getKind() == MCExpr::SymbolRef;
204 static bool classof(const MCSymbolRefExpr *) { return true; }
207 /// MCUnaryExpr - Unary assembler expressions.
208 class MCUnaryExpr : public MCExpr {
211 LNot, ///< Logical negation.
212 Minus, ///< Unary minus.
213 Not, ///< Bitwise negation.
214 Plus ///< Unary plus.
221 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
222 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
225 /// @name Construction
228 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
230 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
231 return Create(LNot, Expr, Ctx);
233 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
234 return Create(Minus, Expr, Ctx);
236 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
237 return Create(Not, Expr, Ctx);
239 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
240 return Create(Plus, Expr, Ctx);
247 /// getOpcode - Get the kind of this unary expression.
248 Opcode getOpcode() const { return Op; }
250 /// getSubExpr - Get the child of this unary expression.
251 const MCExpr *getSubExpr() const { return Expr; }
255 static bool classof(const MCExpr *E) {
256 return E->getKind() == MCExpr::Unary;
258 static bool classof(const MCUnaryExpr *) { return true; }
261 /// MCBinaryExpr - Binary assembler expressions.
262 class MCBinaryExpr : public MCExpr {
266 And, ///< Bitwise and.
267 Div, ///< Signed division.
268 EQ, ///< Equality comparison.
269 GT, ///< Signed greater than comparison (result is either 0 or some
270 ///< target-specific non-zero value)
271 GTE, ///< Signed greater than or equal comparison (result is either 0 or
272 ///< some target-specific non-zero value).
273 LAnd, ///< Logical and.
274 LOr, ///< Logical or.
275 LT, ///< Signed less than comparison (result is either 0 or
276 ///< some target-specific non-zero value).
277 LTE, ///< Signed less than or equal comparison (result is either 0 or
278 ///< some target-specific non-zero value).
279 Mod, ///< Signed remainder.
280 Mul, ///< Multiplication.
281 NE, ///< Inequality comparison.
283 Shl, ///< Shift left.
284 Shr, ///< Shift right (arithmetic or logical, depending on target)
285 Sub, ///< Subtraction.
286 Xor ///< Bitwise exclusive or.
291 const MCExpr *LHS, *RHS;
293 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
294 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
297 /// @name Construction
300 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
301 const MCExpr *RHS, MCContext &Ctx);
302 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
304 return Create(Add, LHS, RHS, Ctx);
306 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
308 return Create(And, LHS, RHS, Ctx);
310 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
312 return Create(Div, LHS, RHS, Ctx);
314 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
316 return Create(EQ, LHS, RHS, Ctx);
318 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
320 return Create(GT, LHS, RHS, Ctx);
322 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
324 return Create(GTE, LHS, RHS, Ctx);
326 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
328 return Create(LAnd, LHS, RHS, Ctx);
330 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
332 return Create(LOr, LHS, RHS, Ctx);
334 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
336 return Create(LT, LHS, RHS, Ctx);
338 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
340 return Create(LTE, LHS, RHS, Ctx);
342 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
344 return Create(Mod, LHS, RHS, Ctx);
346 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
348 return Create(Mul, LHS, RHS, Ctx);
350 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
352 return Create(NE, LHS, RHS, Ctx);
354 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
356 return Create(Or, LHS, RHS, Ctx);
358 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
360 return Create(Shl, LHS, RHS, Ctx);
362 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
364 return Create(Shr, LHS, RHS, Ctx);
366 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
368 return Create(Sub, LHS, RHS, Ctx);
370 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
372 return Create(Xor, LHS, RHS, Ctx);
379 /// getOpcode - Get the kind of this binary expression.
380 Opcode getOpcode() const { return Op; }
382 /// getLHS - Get the left-hand side expression of the binary operator.
383 const MCExpr *getLHS() const { return LHS; }
385 /// getRHS - Get the right-hand side expression of the binary operator.
386 const MCExpr *getRHS() const { return RHS; }
390 static bool classof(const MCExpr *E) {
391 return E->getKind() == MCExpr::Binary;
393 static bool classof(const MCBinaryExpr *) { return true; }
396 /// MCTargetExpr - This is an extension point for target-specific MCExpr
397 /// subclasses to implement.
399 /// NOTE: All subclasses are required to have trivial destructors because
400 /// MCExprs are bump pointer allocated and not destructed.
401 class MCTargetExpr : public MCExpr {
402 virtual void Anchor();
404 MCTargetExpr() : MCExpr(Target) {}
405 virtual ~MCTargetExpr() {}
408 virtual void PrintImpl(raw_ostream &OS) const = 0;
409 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
410 const MCAsmLayout *Layout) const = 0;
413 static bool classof(const MCExpr *E) {
414 return E->getKind() == MCExpr::Target;
416 static bool classof(const MCTargetExpr *) { return true; }
419 } // end namespace llvm