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/ADT/DenseMap.h"
14 #include "llvm/Support/Casting.h"
15 #include "llvm/Support/DataTypes.h"
28 typedef DenseMap<const MCSectionData*, uint64_t> SectionAddrMap;
30 /// MCExpr - Base class for the full range of assembler expressions which are
31 /// needed for parsing.
35 Binary, ///< Binary expressions.
36 Constant, ///< Constant expressions.
37 SymbolRef, ///< References to labels and assigned expressions.
38 Unary, ///< Unary expressions.
39 Target ///< Target specific expression.
45 MCExpr(const MCExpr&); // DO NOT IMPLEMENT
46 void operator=(const MCExpr&); // DO NOT IMPLEMENT
48 bool EvaluateAsAbsolute(int64_t &Res, const MCAssembler *Asm,
49 const MCAsmLayout *Layout,
50 const SectionAddrMap *Addrs) const;
52 explicit MCExpr(ExprKind _Kind) : Kind(_Kind) {}
54 bool EvaluateAsRelocatableImpl(MCValue &Res, const MCAssembler *Asm,
55 const MCAsmLayout *Layout,
56 const SectionAddrMap *Addrs,
62 ExprKind getKind() const { return Kind; }
65 /// @name Utility Methods
68 void print(raw_ostream &OS) const;
72 /// @name Expression Evaluation
75 /// EvaluateAsAbsolute - Try to evaluate the expression to an absolute value.
77 /// @param Res - The absolute value, if evaluation succeeds.
78 /// @param Layout - The assembler layout object to use for evaluating symbol
79 /// values. If not given, then only non-symbolic expressions will be
81 /// @result - True on success.
82 bool EvaluateAsAbsolute(int64_t &Res) const;
83 bool EvaluateAsAbsolute(int64_t &Res, const MCAssembler &Asm) const;
84 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout) const;
85 bool EvaluateAsAbsolute(int64_t &Res, const MCAsmLayout &Layout,
86 const SectionAddrMap &Addrs) const;
88 /// EvaluateAsRelocatable - Try to evaluate the expression to a relocatable
89 /// value, i.e. an expression of the fixed form (a - b + constant).
91 /// @param Res - The relocatable value, if evaluation succeeds.
92 /// @param Layout - The assembler layout object to use for evaluating values.
93 /// @result - True on success.
94 bool EvaluateAsRelocatable(MCValue &Res, const MCAsmLayout &Layout) const;
96 /// FindAssociatedSection - Find the "associated section" for this expression,
97 /// which is currently defined as the absolute section for constants, or
98 /// otherwise the section associated with the first defined symbol in the
100 const MCSection *FindAssociatedSection() const;
104 static bool classof(const MCExpr *) { return true; }
107 inline raw_ostream &operator<<(raw_ostream &OS, const MCExpr &E) {
112 //// MCConstantExpr - Represent a constant integer expression.
113 class MCConstantExpr : public MCExpr {
116 explicit MCConstantExpr(int64_t _Value)
117 : MCExpr(MCExpr::Constant), Value(_Value) {}
120 /// @name Construction
123 static const MCConstantExpr *Create(int64_t Value, MCContext &Ctx);
129 int64_t getValue() const { return Value; }
133 static bool classof(const MCExpr *E) {
134 return E->getKind() == MCExpr::Constant;
136 static bool classof(const MCConstantExpr *) { return true; }
139 /// MCSymbolRefExpr - Represent a reference to a symbol from inside an
142 /// A symbol reference in an expression may be a use of a label, a use of an
143 /// assembler variable (defined constant), or constitute an implicit definition
144 /// of the symbol as external.
145 class MCSymbolRefExpr : public MCExpr {
164 VK_TLVP, // Mach-O thread local variable relocation
165 // FIXME: We'd really like to use the generic Kinds listed above for these.
166 VK_ARM_PLT, // ARM-style PLT references. i.e., (PLT) instead of @PLT
167 VK_ARM_TLSGD, // ditto for TLSGD, GOT, GOTOFF, TPOFF and GOTTPOFF
174 VK_PPC_HA16, // ha16(symbol)
175 VK_PPC_LO16 // lo16(symbol)
179 /// The symbol being referenced.
180 const MCSymbol *Symbol;
182 /// The symbol reference modifier.
183 const VariantKind Kind;
185 explicit MCSymbolRefExpr(const MCSymbol *_Symbol, VariantKind _Kind)
186 : MCExpr(MCExpr::SymbolRef), Symbol(_Symbol), Kind(_Kind) {}
189 /// @name Construction
192 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, MCContext &Ctx) {
193 return MCSymbolRefExpr::Create(Symbol, VK_None, Ctx);
196 static const MCSymbolRefExpr *Create(const MCSymbol *Symbol, VariantKind Kind,
198 static const MCSymbolRefExpr *Create(StringRef Name, VariantKind Kind,
205 const MCSymbol &getSymbol() const { return *Symbol; }
207 VariantKind getKind() const { return Kind; }
210 /// @name Static Utility Functions
213 static StringRef getVariantKindName(VariantKind Kind);
215 static VariantKind getVariantKindForName(StringRef Name);
219 static bool classof(const MCExpr *E) {
220 return E->getKind() == MCExpr::SymbolRef;
222 static bool classof(const MCSymbolRefExpr *) { return true; }
225 /// MCUnaryExpr - Unary assembler expressions.
226 class MCUnaryExpr : public MCExpr {
229 LNot, ///< Logical negation.
230 Minus, ///< Unary minus.
231 Not, ///< Bitwise negation.
232 Plus ///< Unary plus.
239 MCUnaryExpr(Opcode _Op, const MCExpr *_Expr)
240 : MCExpr(MCExpr::Unary), Op(_Op), Expr(_Expr) {}
243 /// @name Construction
246 static const MCUnaryExpr *Create(Opcode Op, const MCExpr *Expr,
248 static const MCUnaryExpr *CreateLNot(const MCExpr *Expr, MCContext &Ctx) {
249 return Create(LNot, Expr, Ctx);
251 static const MCUnaryExpr *CreateMinus(const MCExpr *Expr, MCContext &Ctx) {
252 return Create(Minus, Expr, Ctx);
254 static const MCUnaryExpr *CreateNot(const MCExpr *Expr, MCContext &Ctx) {
255 return Create(Not, Expr, Ctx);
257 static const MCUnaryExpr *CreatePlus(const MCExpr *Expr, MCContext &Ctx) {
258 return Create(Plus, Expr, Ctx);
265 /// getOpcode - Get the kind of this unary expression.
266 Opcode getOpcode() const { return Op; }
268 /// getSubExpr - Get the child of this unary expression.
269 const MCExpr *getSubExpr() const { return Expr; }
273 static bool classof(const MCExpr *E) {
274 return E->getKind() == MCExpr::Unary;
276 static bool classof(const MCUnaryExpr *) { return true; }
279 /// MCBinaryExpr - Binary assembler expressions.
280 class MCBinaryExpr : public MCExpr {
284 And, ///< Bitwise and.
285 Div, ///< Signed division.
286 EQ, ///< Equality comparison.
287 GT, ///< Signed greater than comparison (result is either 0 or some
288 ///< target-specific non-zero value)
289 GTE, ///< Signed greater than or equal comparison (result is either 0 or
290 ///< some target-specific non-zero value).
291 LAnd, ///< Logical and.
292 LOr, ///< Logical or.
293 LT, ///< Signed less than comparison (result is either 0 or
294 ///< some target-specific non-zero value).
295 LTE, ///< Signed less than or equal comparison (result is either 0 or
296 ///< some target-specific non-zero value).
297 Mod, ///< Signed remainder.
298 Mul, ///< Multiplication.
299 NE, ///< Inequality comparison.
301 Shl, ///< Shift left.
302 Shr, ///< Shift right (arithmetic or logical, depending on target)
303 Sub, ///< Subtraction.
304 Xor ///< Bitwise exclusive or.
309 const MCExpr *LHS, *RHS;
311 MCBinaryExpr(Opcode _Op, const MCExpr *_LHS, const MCExpr *_RHS)
312 : MCExpr(MCExpr::Binary), Op(_Op), LHS(_LHS), RHS(_RHS) {}
315 /// @name Construction
318 static const MCBinaryExpr *Create(Opcode Op, const MCExpr *LHS,
319 const MCExpr *RHS, MCContext &Ctx);
320 static const MCBinaryExpr *CreateAdd(const MCExpr *LHS, const MCExpr *RHS,
322 return Create(Add, LHS, RHS, Ctx);
324 static const MCBinaryExpr *CreateAnd(const MCExpr *LHS, const MCExpr *RHS,
326 return Create(And, LHS, RHS, Ctx);
328 static const MCBinaryExpr *CreateDiv(const MCExpr *LHS, const MCExpr *RHS,
330 return Create(Div, LHS, RHS, Ctx);
332 static const MCBinaryExpr *CreateEQ(const MCExpr *LHS, const MCExpr *RHS,
334 return Create(EQ, LHS, RHS, Ctx);
336 static const MCBinaryExpr *CreateGT(const MCExpr *LHS, const MCExpr *RHS,
338 return Create(GT, LHS, RHS, Ctx);
340 static const MCBinaryExpr *CreateGTE(const MCExpr *LHS, const MCExpr *RHS,
342 return Create(GTE, LHS, RHS, Ctx);
344 static const MCBinaryExpr *CreateLAnd(const MCExpr *LHS, const MCExpr *RHS,
346 return Create(LAnd, LHS, RHS, Ctx);
348 static const MCBinaryExpr *CreateLOr(const MCExpr *LHS, const MCExpr *RHS,
350 return Create(LOr, LHS, RHS, Ctx);
352 static const MCBinaryExpr *CreateLT(const MCExpr *LHS, const MCExpr *RHS,
354 return Create(LT, LHS, RHS, Ctx);
356 static const MCBinaryExpr *CreateLTE(const MCExpr *LHS, const MCExpr *RHS,
358 return Create(LTE, LHS, RHS, Ctx);
360 static const MCBinaryExpr *CreateMod(const MCExpr *LHS, const MCExpr *RHS,
362 return Create(Mod, LHS, RHS, Ctx);
364 static const MCBinaryExpr *CreateMul(const MCExpr *LHS, const MCExpr *RHS,
366 return Create(Mul, LHS, RHS, Ctx);
368 static const MCBinaryExpr *CreateNE(const MCExpr *LHS, const MCExpr *RHS,
370 return Create(NE, LHS, RHS, Ctx);
372 static const MCBinaryExpr *CreateOr(const MCExpr *LHS, const MCExpr *RHS,
374 return Create(Or, LHS, RHS, Ctx);
376 static const MCBinaryExpr *CreateShl(const MCExpr *LHS, const MCExpr *RHS,
378 return Create(Shl, LHS, RHS, Ctx);
380 static const MCBinaryExpr *CreateShr(const MCExpr *LHS, const MCExpr *RHS,
382 return Create(Shr, LHS, RHS, Ctx);
384 static const MCBinaryExpr *CreateSub(const MCExpr *LHS, const MCExpr *RHS,
386 return Create(Sub, LHS, RHS, Ctx);
388 static const MCBinaryExpr *CreateXor(const MCExpr *LHS, const MCExpr *RHS,
390 return Create(Xor, LHS, RHS, Ctx);
397 /// getOpcode - Get the kind of this binary expression.
398 Opcode getOpcode() const { return Op; }
400 /// getLHS - Get the left-hand side expression of the binary operator.
401 const MCExpr *getLHS() const { return LHS; }
403 /// getRHS - Get the right-hand side expression of the binary operator.
404 const MCExpr *getRHS() const { return RHS; }
408 static bool classof(const MCExpr *E) {
409 return E->getKind() == MCExpr::Binary;
411 static bool classof(const MCBinaryExpr *) { return true; }
414 /// MCTargetExpr - This is an extension point for target-specific MCExpr
415 /// subclasses to implement.
417 /// NOTE: All subclasses are required to have trivial destructors because
418 /// MCExprs are bump pointer allocated and not destructed.
419 class MCTargetExpr : public MCExpr {
420 virtual void Anchor();
422 MCTargetExpr() : MCExpr(Target) {}
423 virtual ~MCTargetExpr() {}
426 virtual void PrintImpl(raw_ostream &OS) const = 0;
427 virtual bool EvaluateAsRelocatableImpl(MCValue &Res,
428 const MCAsmLayout *Layout) const = 0;
429 virtual void AddValueSymbols(MCAssembler *) const = 0;
430 virtual const MCSection *FindAssociatedSection() const = 0;
432 static bool classof(const MCExpr *E) {
433 return E->getKind() == MCExpr::Target;
435 static bool classof(const MCTargetExpr *) { return true; }
438 } // end namespace llvm