Convert APint::{fromString,APInt,getBitsNeeded} to use StringRef.
- Patch by Erick Tryzelaar, with some edits (and a bug fix) from me.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78885 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/APInt.cpp b/lib/Support/APInt.cpp
index daf2244..e352b63 100644
--- a/lib/Support/APInt.cpp
+++ b/lib/Support/APInt.cpp
@@ -14,6 +14,7 @@
#define DEBUG_TYPE "apint"
#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Support/Debug.h"
@@ -75,11 +76,10 @@
clearUnusedBits();
}
-APInt::APInt(unsigned numbits, const char StrStart[], unsigned slen,
- uint8_t radix)
+APInt::APInt(unsigned numbits, const StringRef& Str, uint8_t radix)
: BitWidth(numbits), VAL(0) {
assert(BitWidth && "bitwidth too small");
- fromString(numbits, StrStart, slen, radix);
+ fromString(numbits, Str, radix);
}
APInt& APInt::AssignSlowCase(const APInt& RHS) {
@@ -587,15 +587,16 @@
return *this;
}
-unsigned APInt::getBitsNeeded(const char* str, unsigned slen, uint8_t radix) {
- assert(str != 0 && "Invalid value string");
- assert(slen > 0 && "Invalid string length");
+unsigned APInt::getBitsNeeded(const StringRef& str, uint8_t radix) {
+ assert(!str.empty() && "Invalid string length");
+
+ size_t slen = str.size();
// Each computation below needs to know if its negative
- unsigned isNegative = str[0] == '-';
+ unsigned isNegative = str.front() == '-';
if (isNegative) {
slen--;
- str++;
+ assert(slen && "string is only a minus!");
}
// For radixes of power-of-two values, the bits required is accurately and
// easily computed
@@ -618,7 +619,7 @@
unsigned sufficient = slen*64/18;
// Convert to the actual binary value.
- APInt tmp(sufficient, str, slen, radix);
+ APInt tmp(sufficient, str.substr(isNegative), radix);
// Compute how many bits are required.
return isNegative + tmp.logBase2() + 1;
@@ -2001,15 +2002,19 @@
divide(LHS, lhsWords, RHS, rhsWords, &Quotient, &Remainder);
}
-void APInt::fromString(unsigned numbits, const char *str, unsigned slen,
- uint8_t radix) {
+void APInt::fromString(unsigned numbits, const StringRef& str, uint8_t radix) {
// Check our assumptions here
assert((radix == 10 || radix == 8 || radix == 16 || radix == 2) &&
"Radix should be 2, 8, 10, or 16!");
- assert(str && "String is null?");
- bool isNeg = str[0] == '-';
- if (isNeg)
- str++, slen--;
+ assert(!str.empty() && "Invalid string length");
+ StringRef::iterator p = str.begin();
+ size_t slen = str.size();
+ bool isNeg = *p == '-';
+ if (isNeg) {
+ p++;
+ slen--;
+ assert(slen && "string is only a minus!");
+ }
assert((slen <= numbits || radix != 2) && "Insufficient bit width");
assert(((slen-1)*3 <= numbits || radix != 8) && "Insufficient bit width");
assert(((slen-1)*4 <= numbits || radix != 16) && "Insufficient bit width");
@@ -2028,10 +2033,10 @@
APInt apradix(getBitWidth(), radix);
// Enter digit traversal loop
- for (unsigned i = 0; i < slen; i++) {
+ for (StringRef::iterator e = str.end(); p != e; ++p) {
// Get a digit
unsigned digit = 0;
- char cdigit = str[i];
+ char cdigit = *p;
if (radix == 16) {
if (!isxdigit(cdigit))
llvm_unreachable("Invalid hex digit in string");