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 {
140 VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the asm file)
141 VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the asm file)
142 VK_ARM_PLT, // ARM-style PLT symbol references. i.e., (PLT) instead of @PLT
143 VK_TLVP // Mach-O thread local variable relocation
147 /// The symbol being referenced.
148 const MCSymbol *Symbol;
150 /// The symbol reference modifier.
151 const VariantKind Kind;
153 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
154 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
157 /// @name Construction
160 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
161 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
164 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
166 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
173 const MCSymbol &getSymbol() const { return *Symbol; }
175 VariantKind getKind() const { return Kind; }
178 /// @name Static Utility Functions
181 static StringRef getVariantKindName(VariantKind Kind);
183 static VariantKind getVariantKindForName(StringRef Name);
187 static bool classof(const MCExpr *E) {
188 return E->getKind() == MCExpr::SymbolRef;
190 static bool classof(const MCSymbolRefExpr *) { return true; }
193 /// MCUnaryExpr - Unary assembler expressions.
194 class MCUnaryExpr : public MCExpr {
197 LNot, ///< Logical negation.
198 Minus, ///< Unary minus.
199 Not, ///< Bitwise negation.
200 Plus ///< Unary plus.
207 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
208 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
211 /// @name Construction
214 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
216 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
217 return Create(LNot, Expr, Ctx);
219 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
220 return Create(Minus, Expr, Ctx);
222 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
223 return Create(Not, Expr, Ctx);
225 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
226 return Create(Plus, Expr, Ctx);
233 /// getOpcode - Get the kind of this unary expression.
234 Opcode getOpcode() const { return Op; }
236 /// getSubExpr - Get the child of this unary expression.
237 const MCExpr *getSubExpr() const { return Expr; }
241 static bool classof(const MCExpr *E) {
242 return E->getKind() == MCExpr::Unary;
244 static bool classof(const MCUnaryExpr *) { return true; }
247 /// MCBinaryExpr - Binary assembler expressions.
248 class MCBinaryExpr : public MCExpr {
252 And, ///< Bitwise and.
253 Div, ///< Signed division.
254 EQ, ///< Equality comparison.
255 GT, ///< Signed greater than comparison (result is either 0 or some
256 ///< target-specific non-zero value)
257 GTE, ///< Signed greater than or equal comparison (result is either 0 or
258 ///< some target-specific non-zero value).
259 LAnd, ///< Logical and.
260 LOr, ///< Logical or.
261 LT, ///< Signed less than comparison (result is either 0 or
262 ///< some target-specific non-zero value).
263 LTE, ///< Signed less than or equal comparison (result is either 0 or
264 ///< some target-specific non-zero value).
265 Mod, ///< Signed remainder.
266 Mul, ///< Multiplication.
267 NE, ///< Inequality comparison.
269 Shl, ///< Shift left.
270 Shr, ///< Shift right (arithmetic or logical, depending on target)
271 Sub, ///< Subtraction.
272 Xor ///< Bitwise exclusive or.
277 const MCExpr *LHS, *RHS;
279 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
280 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
283 /// @name Construction
286 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
287 const MCExpr *RHS, MCContext &Ctx);
288 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
290 return Create(Add, LHS, RHS, Ctx);
292 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
294 return Create(And, LHS, RHS, Ctx);
296 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
298 return Create(Div, LHS, RHS, Ctx);
300 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
302 return Create(EQ, LHS, RHS, Ctx);
304 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
306 return Create(GT, LHS, RHS, Ctx);
308 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
310 return Create(GTE, LHS, RHS, Ctx);
312 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
314 return Create(LAnd, LHS, RHS, Ctx);
316 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
318 return Create(LOr, LHS, RHS, Ctx);
320 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
322 return Create(LT, LHS, RHS, Ctx);
324 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
326 return Create(LTE, LHS, RHS, Ctx);
328 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
330 return Create(Mod, LHS, RHS, Ctx);
332 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
334 return Create(Mul, LHS, RHS, Ctx);
336 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
338 return Create(NE, LHS, RHS, Ctx);
340 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
342 return Create(Or, LHS, RHS, Ctx);
344 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
346 return Create(Shl, LHS, RHS, Ctx);
348 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
350 return Create(Shr, LHS, RHS, Ctx);
352 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
354 return Create(Sub, LHS, RHS, Ctx);
356 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
358 return Create(Xor, LHS, RHS, Ctx);
365 /// getOpcode - Get the kind of this binary expression.
366 Opcode getOpcode() const { return Op; }
368 /// getLHS - Get the left-hand side expression of the binary operator.
369 const MCExpr *getLHS() const { return LHS; }
371 /// getRHS - Get the right-hand side expression of the binary operator.
372 const MCExpr *getRHS() const { return RHS; }
376 static bool classof(const MCExpr *E) {
377 return E->getKind() == MCExpr::Binary;
379 static bool classof(const MCBinaryExpr *) { return true; }
382 /// MCTargetExpr - This is an extension point for target-specific MCExpr
383 /// subclasses to implement.
385 /// NOTE: All subclasses are required to have trivial destructors because
386 /// MCExprs are bump pointer allocated and not destructed.
387 class MCTargetExpr : public MCExpr {
388 virtual void Anchor();
390 MCTargetExpr() : MCExpr(Target) {}
391 virtual ~MCTargetExpr() {}
394 virtual void PrintImpl(raw_ostream &OS) const = 0;
395 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
396 const MCAsmLayout *Layout) const = 0;
399 static bool classof(const MCExpr *E) {
400 return E->getKind() == MCExpr::Target;
402 static bool classof(const MCTargetExpr *) { return true; }
405 } // end namespace llvm