llvm-6502/support/lib/Support/StringExtras.cpp

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#include "llvm/Support/StringExtras.h"
#include "llvm/ConstPoolVals.h"
#include "llvm/DerivedTypes.h"
// Can we treat the specified array as a string? Only if it is an array of
// ubytes or non-negative sbytes.
//
bool isStringCompatible(ConstPoolArray *CPA) {
const Type *ETy = cast<ArrayType>(CPA->getType())->getElementType();
if (ETy == Type::UByteTy) return true;
if (ETy != Type::SByteTy) return false;
for (unsigned i = 0; i < CPA->getNumOperands(); ++i)
if (cast<ConstPoolSInt>(CPA->getOperand(i))->getValue() < 0)
return false;
return true;
}
// toOctal - Convert the low order bits of X into an octal letter
static inline char toOctal(int X) {
return (X&7)+'0';
}
// getAsCString - Return the specified array as a C compatible string, only if
// the predicate isStringCompatible is true.
//
string getAsCString(ConstPoolArray *CPA) {
if (isStringCompatible(CPA)) {
string Result;
const Type *ETy = cast<ArrayType>(CPA->getType())->getElementType();
Result = "\"";
for (unsigned i = 0; i < CPA->getNumOperands(); ++i) {
unsigned char C = (ETy == Type::SByteTy) ?
(unsigned char)cast<ConstPoolSInt>(CPA->getOperand(i))->getValue() :
(unsigned char)cast<ConstPoolUInt>(CPA->getOperand(i))->getValue();
if (isprint(C)) {
Result += C;
} else {
switch(C) {
case '\a': Result += "\\a"; break;
case '\b': Result += "\\b"; break;
case '\f': Result += "\\f"; break;
case '\n': Result += "\\n"; break;
case '\r': Result += "\\r"; break;
case '\t': Result += "\\t"; break;
case '\v': Result += "\\v"; break;
default:
Result += '\\';
Result += toOctal(C >> 6);
Result += toOctal(C >> 3);
Result += toOctal(C >> 0);
break;
}
}
}
Result += "\"";
return Result;
} else {
return CPA->getStrValue();
}
}