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_IR_INLINEASM_H
17 #define LLVM_IR_INLINEASM_H
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/IR/Value.h"
28 struct InlineAsmKeyType;
29 template<class ValType, class ValRefType, class TypeClass, class ConstantClass,
31 class ConstantUniqueMap;
32 template<class ConstantClass, class TypeClass, class ValType>
33 struct ConstantCreator;
35 class InlineAsm : public Value {
43 friend struct ConstantCreator<InlineAsm, PointerType, InlineAsmKeyType>;
44 friend class ConstantUniqueMap<InlineAsmKeyType, const InlineAsmKeyType&,
45 PointerType, InlineAsm, false>;
47 InlineAsm(const InlineAsm &) LLVM_DELETED_FUNCTION;
48 void operator=(const InlineAsm&) LLVM_DELETED_FUNCTION;
50 std::string AsmString, Constraints;
55 InlineAsm(PointerType *Ty, const std::string &AsmString,
56 const std::string &Constraints, bool hasSideEffects,
57 bool isAlignStack, AsmDialect asmDialect);
60 /// When the ConstantUniqueMap merges two types and makes two InlineAsms
61 /// identical, it destroys one of them with this method.
62 void destroyConstant();
65 /// InlineAsm::get - Return the specified uniqued inline asm string.
67 static InlineAsm *get(FunctionType *Ty, StringRef AsmString,
68 StringRef Constraints, bool hasSideEffects,
69 bool isAlignStack = false,
70 AsmDialect asmDialect = AD_ATT);
72 bool hasSideEffects() const { return HasSideEffects; }
73 bool isAlignStack() const { return IsAlignStack; }
74 AsmDialect getDialect() const { return Dialect; }
76 /// getType - InlineAsm's are always pointers.
78 PointerType *getType() const {
79 return reinterpret_cast<PointerType*>(Value::getType());
82 /// getFunctionType - InlineAsm's are always pointers to functions.
84 FunctionType *getFunctionType() const;
86 const std::string &getAsmString() const { return AsmString; }
87 const std::string &getConstraintString() const { return Constraints; }
89 /// Verify - This static method can be used by the parser to check to see if
90 /// the specified constraint string is legal for the type. This returns true
91 /// if legal, false if not.
93 static bool Verify(FunctionType *Ty, StringRef Constraints);
95 // Constraint String Parsing
96 enum ConstraintPrefix {
102 typedef std::vector<std::string> ConstraintCodeVector;
104 struct SubConstraintInfo {
105 /// MatchingInput - If this is not -1, this is an output constraint where an
106 /// input constraint is required to match it (e.g. "0"). The value is the
107 /// constraint number that matches this one (for example, if this is
108 /// constraint #0 and constraint #4 has the value "0", this will be 4).
109 signed char MatchingInput;
110 /// Code - The constraint code, either the register name (in braces) or the
111 /// constraint letter/number.
112 ConstraintCodeVector Codes;
113 /// Default constructor.
114 SubConstraintInfo() : MatchingInput(-1) {}
117 typedef std::vector<SubConstraintInfo> SubConstraintInfoVector;
118 struct ConstraintInfo;
119 typedef std::vector<ConstraintInfo> ConstraintInfoVector;
121 struct ConstraintInfo {
122 /// Type - The basic type of the constraint: input/output/clobber
124 ConstraintPrefix Type;
126 /// isEarlyClobber - "&": output operand writes result before inputs are all
127 /// read. This is only ever set for an output operand.
130 /// MatchingInput - If this is not -1, this is an output constraint where an
131 /// input constraint is required to match it (e.g. "0"). The value is the
132 /// constraint number that matches this one (for example, if this is
133 /// constraint #0 and constraint #4 has the value "0", this will be 4).
134 signed char MatchingInput;
136 /// hasMatchingInput - Return true if this is an output constraint that has
137 /// a matching input constraint.
138 bool hasMatchingInput() const { return MatchingInput != -1; }
140 /// isCommutative - This is set to true for a constraint that is commutative
141 /// with the next operand.
144 /// isIndirect - True if this operand is an indirect operand. This means
145 /// that the address of the source or destination is present in the call
146 /// instruction, instead of it being returned or passed in explicitly. This
147 /// is represented with a '*' in the asm string.
150 /// Code - The constraint code, either the register name (in braces) or the
151 /// constraint letter/number.
152 ConstraintCodeVector Codes;
154 /// isMultipleAlternative - '|': has multiple-alternative constraints.
155 bool isMultipleAlternative;
157 /// multipleAlternatives - If there are multiple alternative constraints,
158 /// this array will contain them. Otherwise it will be empty.
159 SubConstraintInfoVector multipleAlternatives;
161 /// The currently selected alternative constraint index.
162 unsigned currentAlternativeIndex;
164 ///Default constructor.
167 /// Copy constructor.
168 ConstraintInfo(const ConstraintInfo &other);
170 /// Parse - Analyze the specified string (e.g. "=*&{eax}") and fill in the
171 /// fields in this structure. If the constraint string is not understood,
172 /// return true, otherwise return false.
173 bool Parse(StringRef Str, ConstraintInfoVector &ConstraintsSoFar);
175 /// selectAlternative - Point this constraint to the alternative constraint
176 /// indicated by the index.
177 void selectAlternative(unsigned index);
180 /// ParseConstraints - Split up the constraint string into the specific
181 /// constraints and their prefixes. If this returns an empty vector, and if
182 /// the constraint string itself isn't empty, there was an error parsing.
183 static ConstraintInfoVector ParseConstraints(StringRef ConstraintString);
185 /// ParseConstraints - Parse the constraints of this inlineasm object,
186 /// returning them the same way that ParseConstraints(str) does.
187 ConstraintInfoVector ParseConstraints() const {
188 return ParseConstraints(Constraints);
191 // Methods for support type inquiry through isa, cast, and dyn_cast:
192 static inline bool classof(const Value *V) {
193 return V->getValueID() == Value::InlineAsmVal;
197 // These are helper methods for dealing with flags in the INLINEASM SDNode
200 enum LLVM_ENUM_INT_TYPE(uint32_t) {
201 // Fixed operands on an INLINEASM SDNode.
205 Op_ExtraInfo = 3, // HasSideEffects, IsAlignStack, AsmDialect.
208 // Fixed operands on an INLINEASM MachineInstr.
210 MIOp_ExtraInfo = 1, // HasSideEffects, IsAlignStack, AsmDialect.
211 MIOp_FirstOperand = 2,
213 // Interpretation of the MIOp_ExtraInfo bit field.
214 Extra_HasSideEffects = 1,
215 Extra_IsAlignStack = 2,
216 Extra_AsmDialect = 4,
220 // Inline asm operands map to multiple SDNode / MachineInstr operands.
221 // The first operand is an immediate describing the asm operand, the low
223 Kind_RegUse = 1, // Input register, "r".
224 Kind_RegDef = 2, // Output register, "=r".
225 Kind_RegDefEarlyClobber = 3, // Early-clobber output register, "=&r".
226 Kind_Clobber = 4, // Clobbered register, "~r".
227 Kind_Imm = 5, // Immediate.
228 Kind_Mem = 6, // Memory operand, "m".
230 Flag_MatchingOperand = 0x80000000
233 static unsigned getFlagWord(unsigned Kind, unsigned NumOps) {
234 assert(((NumOps << 3) & ~0xffff) == 0 && "Too many inline asm operands!");
235 assert(Kind >= Kind_RegUse && Kind <= Kind_Mem && "Invalid Kind");
236 return Kind | (NumOps << 3);
239 /// getFlagWordForMatchingOp - Augment an existing flag word returned by
240 /// getFlagWord with information indicating that this input operand is tied
241 /// to a previous output operand.
242 static unsigned getFlagWordForMatchingOp(unsigned InputFlag,
243 unsigned MatchedOperandNo) {
244 assert(MatchedOperandNo <= 0x7fff && "Too big matched operand");
245 assert((InputFlag & ~0xffff) == 0 && "High bits already contain data");
246 return InputFlag | Flag_MatchingOperand | (MatchedOperandNo << 16);
249 /// getFlagWordForRegClass - Augment an existing flag word returned by
250 /// getFlagWord with the required register class for the following register
252 /// A tied use operand cannot have a register class, use the register class
253 /// from the def operand instead.
254 static unsigned getFlagWordForRegClass(unsigned InputFlag, unsigned RC) {
255 // Store RC + 1, reserve the value 0 to mean 'no register class'.
257 assert(RC <= 0x7fff && "Too large register class ID");
258 assert((InputFlag & ~0xffff) == 0 && "High bits already contain data");
259 return InputFlag | (RC << 16);
262 static unsigned getKind(unsigned Flags) {
266 static bool isRegDefKind(unsigned Flag){ return getKind(Flag) == Kind_RegDef;}
267 static bool isImmKind(unsigned Flag) { return getKind(Flag) == Kind_Imm; }
268 static bool isMemKind(unsigned Flag) { return getKind(Flag) == Kind_Mem; }
269 static bool isRegDefEarlyClobberKind(unsigned Flag) {
270 return getKind(Flag) == Kind_RegDefEarlyClobber;
272 static bool isClobberKind(unsigned Flag) {
273 return getKind(Flag) == Kind_Clobber;
276 /// getNumOperandRegisters - Extract the number of registers field from the
277 /// inline asm operand flag.
278 static unsigned getNumOperandRegisters(unsigned Flag) {
279 return (Flag & 0xffff) >> 3;
282 /// isUseOperandTiedToDef - Return true if the flag of the inline asm
283 /// operand indicates it is an use operand that's matched to a def operand.
284 static bool isUseOperandTiedToDef(unsigned Flag, unsigned &Idx) {
285 if ((Flag & Flag_MatchingOperand) == 0)
287 Idx = (Flag & ~Flag_MatchingOperand) >> 16;
291 /// hasRegClassConstraint - Returns true if the flag contains a register
292 /// class constraint. Sets RC to the register class ID.
293 static bool hasRegClassConstraint(unsigned Flag, unsigned &RC) {
294 if (Flag & Flag_MatchingOperand)
296 unsigned High = Flag >> 16;
297 // getFlagWordForRegClass() uses 0 to mean no register class, and otherwise
307 } // End llvm namespace