1 //===-- llvm/InlineAsm.h - Class to represent inline asm strings-*- 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 // This class represents the inline asm strings, which are Value*'s that are
11 // used as the callee operand of call instructions. InlineAsm's are uniqued
12 // like constants, and created via InlineAsm::get(...).
14 //===----------------------------------------------------------------------===//
16 #ifndef LLVM_INLINEASM_H
17 #define LLVM_INLINEASM_H
19 #include "llvm/Value.h"
27 struct InlineAsmKeyType;
28 template<class ValType, class TypeClass, class ConstantClass, bool HasLargeKey>
29 class ConstantUniqueMap;
30 template<class ConstantClass, class TypeClass, class ValType>
31 struct ConstantCreator;
33 class InlineAsm : public Value {
34 friend struct ConstantCreator<InlineAsm, PointerType, InlineAsmKeyType>;
35 friend class ConstantUniqueMap<InlineAsmKeyType, PointerType, InlineAsm,
38 InlineAsm(const InlineAsm &); // do not implement
39 void operator=(const InlineAsm&); // do not implement
41 std::string AsmString, Constraints;
45 InlineAsm(const PointerType *Ty, const std::string &AsmString,
46 const std::string &Constraints, bool hasSideEffects,
50 /// When the ConstantUniqueMap merges two types and makes two InlineAsms
51 /// identical, it destroys one of them with this method.
52 void destroyConstant();
55 /// InlineAsm::get - Return the specified uniqued inline asm string.
57 static InlineAsm *get(const FunctionType *Ty, StringRef AsmString,
58 StringRef Constraints, bool hasSideEffects,
59 bool isAlignStack = false);
61 bool hasSideEffects() const { return HasSideEffects; }
62 bool isAlignStack() const { return IsAlignStack; }
64 /// getType - InlineAsm's are always pointers.
66 const PointerType *getType() const {
67 return reinterpret_cast<const PointerType*>(Value::getType());
70 /// getFunctionType - InlineAsm's are always pointers to functions.
72 const FunctionType *getFunctionType() const;
74 const std::string &getAsmString() const { return AsmString; }
75 const std::string &getConstraintString() const { return Constraints; }
77 /// Verify - This static method can be used by the parser to check to see if
78 /// the specified constraint string is legal for the type. This returns true
79 /// if legal, false if not.
81 static bool Verify(const FunctionType *Ty, StringRef Constraints);
83 // Constraint String Parsing
84 enum ConstraintPrefix {
90 struct SubConstraintInfo {
91 /// MatchingInput - If this is not -1, this is an output constraint where an
92 /// input constraint is required to match it (e.g. "0"). The value is the
93 /// constraint number that matches this one (for example, if this is
94 /// constraint #0 and constraint #4 has the value "0", this will be 4).
95 signed char MatchingInput;
96 /// Code - The constraint code, either the register name (in braces) or the
97 /// constraint letter/number.
98 std::vector<std::string> Codes;
99 /// Default constructor.
100 SubConstraintInfo() : MatchingInput(-1) {}
103 struct ConstraintInfo {
104 /// Type - The basic type of the constraint: input/output/clobber
106 ConstraintPrefix Type;
108 /// isEarlyClobber - "&": output operand writes result before inputs are all
109 /// read. This is only ever set for an output operand.
112 /// MatchingInput - If this is not -1, this is an output constraint where an
113 /// input constraint is required to match it (e.g. "0"). The value is the
114 /// constraint number that matches this one (for example, if this is
115 /// constraint #0 and constraint #4 has the value "0", this will be 4).
116 signed char MatchingInput;
118 /// hasMatchingInput - Return true if this is an output constraint that has
119 /// a matching input constraint.
120 bool hasMatchingInput() const { return MatchingInput != -1; }
122 /// isCommutative - This is set to true for a constraint that is commutative
123 /// with the next operand.
126 /// isIndirect - True if this operand is an indirect operand. This means
127 /// that the address of the source or destination is present in the call
128 /// instruction, instead of it being returned or passed in explicitly. This
129 /// is represented with a '*' in the asm string.
132 /// Code - The constraint code, either the register name (in braces) or the
133 /// constraint letter/number.
134 std::vector<std::string> Codes;
136 /// isMultipleAlternative - '|': has multiple-alternative constraints.
137 bool isMultipleAlternative;
139 /// multipleAlternatives - If there are multiple alternative constraints,
140 /// this array will contain them. Otherwise it will be empty.
141 std::vector<SubConstraintInfo> multipleAlternatives;
143 /// The currently selected alternative constraint index.
144 unsigned currentAlternativeIndex;
146 ///Default constructor.
149 /// Copy constructor.
150 ConstraintInfo(const ConstraintInfo &other);
152 /// Parse - Analyze the specified string (e.g. "=*&{eax}") and fill in the
153 /// fields in this structure. If the constraint string is not understood,
154 /// return true, otherwise return false.
155 bool Parse(StringRef Str,
156 std::vector<InlineAsm::ConstraintInfo> &ConstraintsSoFar);
158 /// selectAlternative - Point this constraint to the alternative constraint
159 /// indicated by the index.
160 void selectAlternative(unsigned index);
163 /// ParseConstraints - Split up the constraint string into the specific
164 /// constraints and their prefixes. If this returns an empty vector, and if
165 /// the constraint string itself isn't empty, there was an error parsing.
166 static std::vector<ConstraintInfo>
167 ParseConstraints(StringRef ConstraintString);
169 /// ParseConstraints - Parse the constraints of this inlineasm object,
170 /// returning them the same way that ParseConstraints(str) does.
171 std::vector<ConstraintInfo>
172 ParseConstraints() const {
173 return ParseConstraints(Constraints);
176 // Methods for support type inquiry through isa, cast, and dyn_cast:
177 static inline bool classof(const InlineAsm *) { return true; }
178 static inline bool classof(const Value *V) {
179 return V->getValueID() == Value::InlineAsmVal;
183 // These are helper methods for dealing with flags in the INLINEASM SDNode
197 Kind_RegDefEarlyClobber = 6,
199 Flag_MatchingOperand = 0x80000000
202 static unsigned getFlagWord(unsigned Kind, unsigned NumOps) {
203 assert(((NumOps << 3) & ~0xffff) == 0 && "Too many inline asm operands!");
204 return Kind | (NumOps << 3);
207 /// getFlagWordForMatchingOp - Augment an existing flag word returned by
208 /// getFlagWord with information indicating that this input operand is tied
209 /// to a previous output operand.
210 static unsigned getFlagWordForMatchingOp(unsigned InputFlag,
211 unsigned MatchedOperandNo) {
212 return InputFlag | Flag_MatchingOperand | (MatchedOperandNo << 16);
215 static unsigned getKind(unsigned Flags) {
219 static bool isRegDefKind(unsigned Flag){ return getKind(Flag) == Kind_RegDef;}
220 static bool isImmKind(unsigned Flag) { return getKind(Flag) == Kind_Imm; }
221 static bool isMemKind(unsigned Flag) { return getKind(Flag) == Kind_Mem; }
222 static bool isRegDefEarlyClobberKind(unsigned Flag) {
223 return getKind(Flag) == Kind_RegDefEarlyClobber;
226 /// getNumOperandRegisters - Extract the number of registers field from the
227 /// inline asm operand flag.
228 static unsigned getNumOperandRegisters(unsigned Flag) {
229 return (Flag & 0xffff) >> 3;
232 /// isUseOperandTiedToDef - Return true if the flag of the inline asm
233 /// operand indicates it is an use operand that's matched to a def operand.
234 static bool isUseOperandTiedToDef(unsigned Flag, unsigned &Idx) {
235 if ((Flag & Flag_MatchingOperand) == 0)
237 Idx = (Flag & ~Flag_MatchingOperand) >> 16;
244 } // End llvm namespace