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"
24 struct AssemblyAnnotationWriter;
29 class InlineAsm : public Value {
30 InlineAsm(const InlineAsm &); // do not implement
31 void operator=(const InlineAsm&); // do not implement
33 std::string AsmString, Constraints;
36 InlineAsm(const FunctionType *Ty, const std::string &AsmString,
37 const std::string &Constraints, bool hasSideEffects);
41 /// InlineAsm::get - Return the the specified uniqued inline asm string.
43 static InlineAsm *get(const FunctionType *Ty, const std::string &AsmString,
44 const std::string &Constraints, bool hasSideEffects);
46 bool hasSideEffects() const { return HasSideEffects; }
48 /// getType - InlineAsm's are always pointers.
50 const PointerType *getType() const {
51 return reinterpret_cast<const PointerType*>(Value::getType());
54 /// getFunctionType - InlineAsm's are always pointers to functions.
56 const FunctionType *getFunctionType() const;
58 const std::string &getAsmString() const { return AsmString; }
59 const std::string &getConstraintString() const { return Constraints; }
61 virtual void print(std::ostream &O) const { print(O, 0); }
62 void print(std::ostream *O) const { if (O) print(*O); }
63 void print(std::ostream &OS, AssemblyAnnotationWriter *AAW) const;
65 /// Verify - This static method can be used by the parser to check to see if
66 /// the specified constraint string is legal for the type. This returns true
67 /// if legal, false if not.
69 static bool Verify(const FunctionType *Ty, const std::string &Constraints);
71 // Constraint String Parsing
72 enum ConstraintPrefix {
78 struct ConstraintInfo {
79 /// Type - The basic type of the constraint: input/output/clobber
81 ConstraintPrefix Type;
83 /// isEarlyClobber - "&": output operand writes result before inputs are all
84 /// read. This is only ever set for an output operand.
87 /// hasMatchingInput - This is set to true for an output constraint iff
88 /// there is an input constraint that is required to match it (e.g. "0").
89 bool hasMatchingInput;
91 /// isCommutative - This is set to true for a constraint that is commutative
92 /// with the next operand.
95 /// isIndirect - True if this operand is an indirect operand. This means
96 /// that the address of the source or destination is present in the call
97 /// instruction, instead of it being returned or passed in explicitly. This
98 /// is represented with a '*' in the asm string.
101 /// Code - The constraint code, either the register name (in braces) or the
102 /// constraint letter/number.
103 std::vector<std::string> Codes;
105 /// Parse - Analyze the specified string (e.g. "=*&{eax}") and fill in the
106 /// fields in this structure. If the constraint string is not understood,
107 /// return true, otherwise return false.
108 bool Parse(const std::string &Str,
109 std::vector<InlineAsm::ConstraintInfo> &ConstraintsSoFar);
112 /// ParseConstraints - Split up the constraint string into the specific
113 /// constraints and their prefixes. If this returns an empty vector, and if
114 /// the constraint string itself isn't empty, there was an error parsing.
115 static std::vector<ConstraintInfo>
116 ParseConstraints(const std::string &ConstraintString);
118 /// ParseConstraints - Parse the constraints of this inlineasm object,
119 /// returning them the same way that ParseConstraints(str) does.
120 std::vector<ConstraintInfo>
121 ParseConstraints() const {
122 return ParseConstraints(Constraints);
125 // Methods for support type inquiry through isa, cast, and dyn_cast:
126 static inline bool classof(const InlineAsm *) { return true; }
127 static inline bool classof(const Value *V) {
128 return V->getValueID() == Value::InlineAsmVal;
132 } // End llvm namespace