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"
20 #include "llvm/ADT/StringRef.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 {
36 friend struct ConstantCreator<InlineAsm, PointerType, InlineAsmKeyType>;
37 friend class ConstantUniqueMap<InlineAsmKeyType, const InlineAsmKeyType&,
38 PointerType, InlineAsm, false>;
40 InlineAsm(const InlineAsm &); // do not implement
41 void operator=(const InlineAsm&); // do not implement
43 std::string AsmString, Constraints;
46 /// AsmDialect - 0 is AT&T (default) and 1 is the Intel dialect.
49 InlineAsm(PointerType *Ty, const std::string &AsmString,
50 const std::string &Constraints, bool hasSideEffects,
51 bool isAlignStack, unsigned asmDialect);
54 /// When the ConstantUniqueMap merges two types and makes two InlineAsms
55 /// identical, it destroys one of them with this method.
56 void destroyConstant();
59 /// InlineAsm::get - Return the specified uniqued inline asm string.
61 static InlineAsm *get(FunctionType *Ty, StringRef AsmString,
62 StringRef Constraints, bool hasSideEffects,
63 bool isAlignStack = false, unsigned asmDialect = 0);
65 bool hasSideEffects() const { return HasSideEffects; }
66 bool isAlignStack() const { return IsAlignStack; }
67 unsigned getDialect() const { return AsmDialect; }
69 /// getType - InlineAsm's are always pointers.
71 PointerType *getType() const {
72 return reinterpret_cast<PointerType*>(Value::getType());
75 /// getFunctionType - InlineAsm's are always pointers to functions.
77 FunctionType *getFunctionType() const;
79 const std::string &getAsmString() const { return AsmString; }
80 const std::string &getConstraintString() const { return Constraints; }
82 /// Verify - This static method can be used by the parser to check to see if
83 /// the specified constraint string is legal for the type. This returns true
84 /// if legal, false if not.
86 static bool Verify(FunctionType *Ty, StringRef Constraints);
88 // Constraint String Parsing
89 enum ConstraintPrefix {
95 typedef std::vector<std::string> ConstraintCodeVector;
97 struct SubConstraintInfo {
98 /// MatchingInput - If this is not -1, this is an output constraint where an
99 /// input constraint is required to match it (e.g. "0"). The value is the
100 /// constraint number that matches this one (for example, if this is
101 /// constraint #0 and constraint #4 has the value "0", this will be 4).
102 signed char MatchingInput;
103 /// Code - The constraint code, either the register name (in braces) or the
104 /// constraint letter/number.
105 ConstraintCodeVector Codes;
106 /// Default constructor.
107 SubConstraintInfo() : MatchingInput(-1) {}
110 typedef std::vector<SubConstraintInfo> SubConstraintInfoVector;
111 struct ConstraintInfo;
112 typedef std::vector<ConstraintInfo> ConstraintInfoVector;
114 struct ConstraintInfo {
115 /// Type - The basic type of the constraint: input/output/clobber
117 ConstraintPrefix Type;
119 /// isEarlyClobber - "&": output operand writes result before inputs are all
120 /// read. This is only ever set for an output operand.
123 /// MatchingInput - If this is not -1, this is an output constraint where an
124 /// input constraint is required to match it (e.g. "0"). The value is the
125 /// constraint number that matches this one (for example, if this is
126 /// constraint #0 and constraint #4 has the value "0", this will be 4).
127 signed char MatchingInput;
129 /// hasMatchingInput - Return true if this is an output constraint that has
130 /// a matching input constraint.
131 bool hasMatchingInput() const { return MatchingInput != -1; }
133 /// isCommutative - This is set to true for a constraint that is commutative
134 /// with the next operand.
137 /// isIndirect - True if this operand is an indirect operand. This means
138 /// that the address of the source or destination is present in the call
139 /// instruction, instead of it being returned or passed in explicitly. This
140 /// is represented with a '*' in the asm string.
143 /// Code - The constraint code, either the register name (in braces) or the
144 /// constraint letter/number.
145 ConstraintCodeVector Codes;
147 /// isMultipleAlternative - '|': has multiple-alternative constraints.
148 bool isMultipleAlternative;
150 /// multipleAlternatives - If there are multiple alternative constraints,
151 /// this array will contain them. Otherwise it will be empty.
152 SubConstraintInfoVector multipleAlternatives;
154 /// The currently selected alternative constraint index.
155 unsigned currentAlternativeIndex;
157 ///Default constructor.
160 /// Copy constructor.
161 ConstraintInfo(const ConstraintInfo &other);
163 /// Parse - Analyze the specified string (e.g. "=*&{eax}") and fill in the
164 /// fields in this structure. If the constraint string is not understood,
165 /// return true, otherwise return false.
166 bool Parse(StringRef Str, ConstraintInfoVector &ConstraintsSoFar);
168 /// selectAlternative - Point this constraint to the alternative constraint
169 /// indicated by the index.
170 void selectAlternative(unsigned index);
173 /// ParseConstraints - Split up the constraint string into the specific
174 /// constraints and their prefixes. If this returns an empty vector, and if
175 /// the constraint string itself isn't empty, there was an error parsing.
176 static ConstraintInfoVector ParseConstraints(StringRef ConstraintString);
178 /// ParseConstraints - Parse the constraints of this inlineasm object,
179 /// returning them the same way that ParseConstraints(str) does.
180 ConstraintInfoVector ParseConstraints() const {
181 return ParseConstraints(Constraints);
184 // Methods for support type inquiry through isa, cast, and dyn_cast:
185 static inline bool classof(const InlineAsm *) { return true; }
186 static inline bool classof(const Value *V) {
187 return V->getValueID() == Value::InlineAsmVal;
191 // These are helper methods for dealing with flags in the INLINEASM SDNode
195 // Fixed operands on an INLINEASM SDNode.
199 Op_ExtraInfo = 3, // HasSideEffects, IsAlignStack
202 // Fixed operands on an INLINEASM MachineInstr.
204 MIOp_ExtraInfo = 1, // HasSideEffects, IsAlignStack
205 MIOp_FirstOperand = 2,
207 // Interpretation of the MIOp_ExtraInfo bit field.
208 Extra_HasSideEffects = 1,
209 Extra_IsAlignStack = 2,
211 // Inline asm operands map to multiple SDNode / MachineInstr operands.
212 // The first operand is an immediate describing the asm operand, the low
214 Kind_RegUse = 1, // Input register, "r".
215 Kind_RegDef = 2, // Output register, "=r".
216 Kind_RegDefEarlyClobber = 3, // Early-clobber output register, "=&r".
217 Kind_Clobber = 4, // Clobbered register, "~r".
218 Kind_Imm = 5, // Immediate.
219 Kind_Mem = 6, // Memory operand, "m".
221 Flag_MatchingOperand = 0x80000000
224 static unsigned getFlagWord(unsigned Kind, unsigned NumOps) {
225 assert(((NumOps << 3) & ~0xffff) == 0 && "Too many inline asm operands!");
226 assert(Kind >= Kind_RegUse && Kind <= Kind_Mem && "Invalid Kind");
227 return Kind | (NumOps << 3);
230 /// getFlagWordForMatchingOp - Augment an existing flag word returned by
231 /// getFlagWord with information indicating that this input operand is tied
232 /// to a previous output operand.
233 static unsigned getFlagWordForMatchingOp(unsigned InputFlag,
234 unsigned MatchedOperandNo) {
235 assert(MatchedOperandNo <= 0x7fff && "Too big matched operand");
236 assert((InputFlag & ~0xffff) == 0 && "High bits already contain data");
237 return InputFlag | Flag_MatchingOperand | (MatchedOperandNo << 16);
240 /// getFlagWordForRegClass - Augment an existing flag word returned by
241 /// getFlagWord with the required register class for the following register
243 /// A tied use operand cannot have a register class, use the register class
244 /// from the def operand instead.
245 static unsigned getFlagWordForRegClass(unsigned InputFlag, unsigned RC) {
246 // Store RC + 1, reserve the value 0 to mean 'no register class'.
248 assert(RC <= 0x7fff && "Too large register class ID");
249 assert((InputFlag & ~0xffff) == 0 && "High bits already contain data");
250 return InputFlag | (RC << 16);
253 static unsigned getKind(unsigned Flags) {
257 static bool isRegDefKind(unsigned Flag){ return getKind(Flag) == Kind_RegDef;}
258 static bool isImmKind(unsigned Flag) { return getKind(Flag) == Kind_Imm; }
259 static bool isMemKind(unsigned Flag) { return getKind(Flag) == Kind_Mem; }
260 static bool isRegDefEarlyClobberKind(unsigned Flag) {
261 return getKind(Flag) == Kind_RegDefEarlyClobber;
263 static bool isClobberKind(unsigned Flag) {
264 return getKind(Flag) == Kind_Clobber;
267 /// getNumOperandRegisters - Extract the number of registers field from the
268 /// inline asm operand flag.
269 static unsigned getNumOperandRegisters(unsigned Flag) {
270 return (Flag & 0xffff) >> 3;
273 /// isUseOperandTiedToDef - Return true if the flag of the inline asm
274 /// operand indicates it is an use operand that's matched to a def operand.
275 static bool isUseOperandTiedToDef(unsigned Flag, unsigned &Idx) {
276 if ((Flag & Flag_MatchingOperand) == 0)
278 Idx = (Flag & ~Flag_MatchingOperand) >> 16;
282 /// hasRegClassConstraint - Returns true if the flag contains a register
283 /// class constraint. Sets RC to the register class ID.
284 static bool hasRegClassConstraint(unsigned Flag, unsigned &RC) {
285 if (Flag & Flag_MatchingOperand)
287 unsigned High = Flag >> 16;
288 // getFlagWordForRegClass() uses 0 to mean no register class, and otherwise
298 } // End llvm namespace