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"
28
class InlineAsm : public Value {
29
InlineAsm(const InlineAsm &); // do not implement
30
void operator=(const InlineAsm&); // do not implement
32
std::string AsmString, Constraints;
36
InlineAsm(const FunctionType *Ty, StringRef AsmString,
37
StringRef Constraints, bool hasSideEffects,
38
bool isAlignStack = false);
42
/// InlineAsm::get - Return the specified uniqued inline asm string.
44
static InlineAsm *get(const FunctionType *Ty, StringRef AsmString,
45
StringRef Constraints, bool hasSideEffects,
46
bool isAlignStack = false);
48
bool hasSideEffects() const { return HasSideEffects; }
49
bool isAlignStack() const { return IsAlignStack; }
51
/// getType - InlineAsm's are always pointers.
53
const PointerType *getType() const {
54
return reinterpret_cast<const PointerType*>(Value::getType());
57
/// getFunctionType - InlineAsm's are always pointers to functions.
59
const FunctionType *getFunctionType() const;
61
const std::string &getAsmString() const { return AsmString; }
62
const std::string &getConstraintString() const { return Constraints; }
64
/// Verify - This static method can be used by the parser to check to see if
65
/// the specified constraint string is legal for the type. This returns true
66
/// if legal, false if not.
68
static bool Verify(const FunctionType *Ty, StringRef Constraints);
70
// Constraint String Parsing
71
enum ConstraintPrefix {
77
struct ConstraintInfo {
78
/// Type - The basic type of the constraint: input/output/clobber
80
ConstraintPrefix Type;
82
/// isEarlyClobber - "&": output operand writes result before inputs are all
83
/// read. This is only ever set for an output operand.
86
/// MatchingInput - If this is not -1, this is an output constraint where an
87
/// input constraint is required to match it (e.g. "0"). The value is the
88
/// constraint number that matches this one (for example, if this is
89
/// constraint #0 and constraint #4 has the value "0", this will be 4).
90
signed char MatchingInput;
92
/// hasMatchingInput - Return true if this is an output constraint that has
93
/// a matching input constraint.
94
bool hasMatchingInput() const { return MatchingInput != -1; }
96
/// isCommutative - This is set to true for a constraint that is commutative
97
/// with the next operand.
100
/// isIndirect - True if this operand is an indirect operand. This means
101
/// that the address of the source or destination is present in the call
102
/// instruction, instead of it being returned or passed in explicitly. This
103
/// is represented with a '*' in the asm string.
106
/// Code - The constraint code, either the register name (in braces) or the
107
/// constraint letter/number.
108
std::vector<std::string> Codes;
110
/// Parse - Analyze the specified string (e.g. "=*&{eax}") and fill in the
111
/// fields in this structure. If the constraint string is not understood,
112
/// return true, otherwise return false.
113
bool Parse(StringRef Str,
114
std::vector<InlineAsm::ConstraintInfo> &ConstraintsSoFar);
117
/// ParseConstraints - Split up the constraint string into the specific
118
/// constraints and their prefixes. If this returns an empty vector, and if
119
/// the constraint string itself isn't empty, there was an error parsing.
120
static std::vector<ConstraintInfo>
121
ParseConstraints(StringRef ConstraintString);
123
/// ParseConstraints - Parse the constraints of this inlineasm object,
124
/// returning them the same way that ParseConstraints(str) does.
125
std::vector<ConstraintInfo>
126
ParseConstraints() const {
127
return ParseConstraints(Constraints);
130
// Methods for support type inquiry through isa, cast, and dyn_cast:
131
static inline bool classof(const InlineAsm *) { return true; }
132
static inline bool classof(const Value *V) {
133
return V->getValueID() == Value::InlineAsmVal;
136
/// getNumOperandRegisters - Extract the number of registers field from the
137
/// inline asm operand flag.
138
static unsigned getNumOperandRegisters(unsigned Flag) {
139
return (Flag & 0xffff) >> 3;
142
/// isUseOperandTiedToDef - Return true if the flag of the inline asm
143
/// operand indicates it is an use operand that's matched to a def operand.
144
static bool isUseOperandTiedToDef(unsigned Flag, unsigned &Idx) {
145
if ((Flag & 0x80000000) == 0)
147
Idx = (Flag & ~0x80000000) >> 16;
154
} // End llvm namespace