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 {
144 VK_ARM_HI16, // The R_ARM_MOVT_ABS relocation (:upper16: in the asm file)
145 VK_ARM_LO16, // The R_ARM_MOVW_ABS_NC relocation (:lower16: in the asm file)
146 VK_ARM_PLT, // ARM-style PLT symbol references. i.e., (PLT) instead of @PLT
147 VK_TLVP // Mach-O thread local variable relocation
151 /// The symbol being referenced.
152 const MCSymbol *Symbol;
154 /// The symbol reference modifier.
155 const VariantKind Kind;
157 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
158 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
161 /// @name Construction
164 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
165 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
168 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
170 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
177 const MCSymbol &getSymbol() const { return *Symbol; }
179 VariantKind getKind() const { return Kind; }
182 /// @name Static Utility Functions
185 static StringRef getVariantKindName(VariantKind Kind);
187 static VariantKind getVariantKindForName(StringRef Name);
191 static bool classof(const MCExpr *E) {
192 return E->getKind() == MCExpr::SymbolRef;
194 static bool classof(const MCSymbolRefExpr *) { return true; }
197 /// MCUnaryExpr - Unary assembler expressions.
198 class MCUnaryExpr : public MCExpr {
201 LNot, ///< Logical negation.
202 Minus, ///< Unary minus.
203 Not, ///< Bitwise negation.
204 Plus ///< Unary plus.
211 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
212 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
215 /// @name Construction
218 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
220 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
221 return Create(LNot, Expr, Ctx);
223 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
224 return Create(Minus, Expr, Ctx);
226 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
227 return Create(Not, Expr, Ctx);
229 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
230 return Create(Plus, Expr, Ctx);
237 /// getOpcode - Get the kind of this unary expression.
238 Opcode getOpcode() const { return Op; }
240 /// getSubExpr - Get the child of this unary expression.
241 const MCExpr *getSubExpr() const { return Expr; }
245 static bool classof(const MCExpr *E) {
246 return E->getKind() == MCExpr::Unary;
248 static bool classof(const MCUnaryExpr *) { return true; }
251 /// MCBinaryExpr - Binary assembler expressions.
252 class MCBinaryExpr : public MCExpr {
256 And, ///< Bitwise and.
257 Div, ///< Signed division.
258 EQ, ///< Equality comparison.
259 GT, ///< Signed greater than comparison (result is either 0 or some
260 ///< target-specific non-zero value)
261 GTE, ///< Signed greater than or equal comparison (result is either 0 or
262 ///< some target-specific non-zero value).
263 LAnd, ///< Logical and.
264 LOr, ///< Logical or.
265 LT, ///< Signed less than comparison (result is either 0 or
266 ///< some target-specific non-zero value).
267 LTE, ///< Signed less than or equal comparison (result is either 0 or
268 ///< some target-specific non-zero value).
269 Mod, ///< Signed remainder.
270 Mul, ///< Multiplication.
271 NE, ///< Inequality comparison.
273 Shl, ///< Shift left.
274 Shr, ///< Shift right (arithmetic or logical, depending on target)
275 Sub, ///< Subtraction.
276 Xor ///< Bitwise exclusive or.
281 const MCExpr *LHS, *RHS;
283 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
284 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
287 /// @name Construction
290 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
291 const MCExpr *RHS, MCContext &Ctx);
292 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
294 return Create(Add, LHS, RHS, Ctx);
296 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
298 return Create(And, LHS, RHS, Ctx);
300 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
302 return Create(Div, LHS, RHS, Ctx);
304 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
306 return Create(EQ, LHS, RHS, Ctx);
308 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
310 return Create(GT, LHS, RHS, Ctx);
312 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
314 return Create(GTE, LHS, RHS, Ctx);
316 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
318 return Create(LAnd, LHS, RHS, Ctx);
320 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
322 return Create(LOr, LHS, RHS, Ctx);
324 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
326 return Create(LT, LHS, RHS, Ctx);
328 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
330 return Create(LTE, LHS, RHS, Ctx);
332 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
334 return Create(Mod, LHS, RHS, Ctx);
336 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
338 return Create(Mul, LHS, RHS, Ctx);
340 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
342 return Create(NE, LHS, RHS, Ctx);
344 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
346 return Create(Or, LHS, RHS, Ctx);
348 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
350 return Create(Shl, LHS, RHS, Ctx);
352 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
354 return Create(Shr, LHS, RHS, Ctx);
356 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
358 return Create(Sub, LHS, RHS, Ctx);
360 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
362 return Create(Xor, LHS, RHS, Ctx);
369 /// getOpcode - Get the kind of this binary expression.
370 Opcode getOpcode() const { return Op; }
372 /// getLHS - Get the left-hand side expression of the binary operator.
373 const MCExpr *getLHS() const { return LHS; }
375 /// getRHS - Get the right-hand side expression of the binary operator.
376 const MCExpr *getRHS() const { return RHS; }
380 static bool classof(const MCExpr *E) {
381 return E->getKind() == MCExpr::Binary;
383 static bool classof(const MCBinaryExpr *) { return true; }
386 /// MCTargetExpr - This is an extension point for target-specific MCExpr
387 /// subclasses to implement.
389 /// NOTE: All subclasses are required to have trivial destructors because
390 /// MCExprs are bump pointer allocated and not destructed.
391 class MCTargetExpr : public MCExpr {
392 virtual void Anchor();
394 MCTargetExpr() : MCExpr(Target) {}
395 virtual ~MCTargetExpr() {}
398 virtual void PrintImpl(raw_ostream &OS) const = 0;
399 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
400 const MCAsmLayout *Layout) const = 0;
403 static bool classof(const MCExpr *E) {
404 return E->getKind() == MCExpr::Target;
406 static bool classof(const MCTargetExpr *) { return true; }
409 } // end namespace llvm