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 {
141 VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the asm file)
142 VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the asm file)
143 VK_ARM_PLT, // ARM-style PLT symbol references. i.e., (PLT) instead of @PLT
144 VK_TLVP // Mach-O thread local variable relocation
148 /// The symbol being referenced.
149 const MCSymbol *Symbol;
151 /// The symbol reference modifier.
152 const VariantKind Kind;
154 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
155 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
158 /// @name Construction
161 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
162 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
165 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
167 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
174 const MCSymbol &getSymbol() const { return *Symbol; }
176 VariantKind getKind() const { return Kind; }
179 /// @name Static Utility Functions
182 static StringRef getVariantKindName(VariantKind Kind);
184 static VariantKind getVariantKindForName(StringRef Name);
188 static bool classof(const MCExpr *E) {
189 return E->getKind() == MCExpr::SymbolRef;
191 static bool classof(const MCSymbolRefExpr *) { return true; }
194 /// MCUnaryExpr - Unary assembler expressions.
195 class MCUnaryExpr : public MCExpr {
198 LNot, ///< Logical negation.
199 Minus, ///< Unary minus.
200 Not, ///< Bitwise negation.
201 Plus ///< Unary plus.
208 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
209 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
212 /// @name Construction
215 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
217 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
218 return Create(LNot, Expr, Ctx);
220 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
221 return Create(Minus, Expr, Ctx);
223 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
224 return Create(Not, Expr, Ctx);
226 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
227 return Create(Plus, Expr, Ctx);
234 /// getOpcode - Get the kind of this unary expression.
235 Opcode getOpcode() const { return Op; }
237 /// getSubExpr - Get the child of this unary expression.
238 const MCExpr *getSubExpr() const { return Expr; }
242 static bool classof(const MCExpr *E) {
243 return E->getKind() == MCExpr::Unary;
245 static bool classof(const MCUnaryExpr *) { return true; }
248 /// MCBinaryExpr - Binary assembler expressions.
249 class MCBinaryExpr : public MCExpr {
253 And, ///< Bitwise and.
254 Div, ///< Signed division.
255 EQ, ///< Equality comparison.
256 GT, ///< Signed greater than comparison (result is either 0 or some
257 ///< target-specific non-zero value)
258 GTE, ///< Signed greater than or equal comparison (result is either 0 or
259 ///< some target-specific non-zero value).
260 LAnd, ///< Logical and.
261 LOr, ///< Logical or.
262 LT, ///< Signed less than comparison (result is either 0 or
263 ///< some target-specific non-zero value).
264 LTE, ///< Signed less than or equal comparison (result is either 0 or
265 ///< some target-specific non-zero value).
266 Mod, ///< Signed remainder.
267 Mul, ///< Multiplication.
268 NE, ///< Inequality comparison.
270 Shl, ///< Shift left.
271 Shr, ///< Shift right (arithmetic or logical, depending on target)
272 Sub, ///< Subtraction.
273 Xor ///< Bitwise exclusive or.
278 const MCExpr *LHS, *RHS;
280 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
281 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
284 /// @name Construction
287 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
288 const MCExpr *RHS, MCContext &Ctx);
289 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
291 return Create(Add, LHS, RHS, Ctx);
293 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
295 return Create(And, LHS, RHS, Ctx);
297 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
299 return Create(Div, LHS, RHS, Ctx);
301 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
303 return Create(EQ, LHS, RHS, Ctx);
305 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
307 return Create(GT, LHS, RHS, Ctx);
309 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
311 return Create(GTE, LHS, RHS, Ctx);
313 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
315 return Create(LAnd, LHS, RHS, Ctx);
317 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
319 return Create(LOr, LHS, RHS, Ctx);
321 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
323 return Create(LT, LHS, RHS, Ctx);
325 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
327 return Create(LTE, LHS, RHS, Ctx);
329 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
331 return Create(Mod, LHS, RHS, Ctx);
333 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
335 return Create(Mul, LHS, RHS, Ctx);
337 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
339 return Create(NE, LHS, RHS, Ctx);
341 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
343 return Create(Or, LHS, RHS, Ctx);
345 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
347 return Create(Shl, LHS, RHS, Ctx);
349 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
351 return Create(Shr, LHS, RHS, Ctx);
353 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
355 return Create(Sub, LHS, RHS, Ctx);
357 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
359 return Create(Xor, LHS, RHS, Ctx);
366 /// getOpcode - Get the kind of this binary expression.
367 Opcode getOpcode() const { return Op; }
369 /// getLHS - Get the left-hand side expression of the binary operator.
370 const MCExpr *getLHS() const { return LHS; }
372 /// getRHS - Get the right-hand side expression of the binary operator.
373 const MCExpr *getRHS() const { return RHS; }
377 static bool classof(const MCExpr *E) {
378 return E->getKind() == MCExpr::Binary;
380 static bool classof(const MCBinaryExpr *) { return true; }
383 /// MCTargetExpr - This is an extension point for target-specific MCExpr
384 /// subclasses to implement.
386 /// NOTE: All subclasses are required to have trivial destructors because
387 /// MCExprs are bump pointer allocated and not destructed.
388 class MCTargetExpr : public MCExpr {
389 virtual void Anchor();
391 MCTargetExpr() : MCExpr(Target) {}
392 virtual ~MCTargetExpr() {}
395 virtual void PrintImpl(raw_ostream &OS) const = 0;
396 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
397 const MCAsmLayout *Layout) const = 0;
400 static bool classof(const MCExpr *E) {
401 return E->getKind() == MCExpr::Target;
403 static bool classof(const MCTargetExpr *) { return true; }
406 } // end namespace llvm