Files
Mozilla/mozilla/ef/Compiler/RegisterAllocator/BitSet.cpp
fur%netscape.com 1c43d4984f This is a copy of regalloc_code2_BRANCH from Netscape's private repository,
as it existed in January of 1998.


git-svn-id: svn://10.0.0.236/branches/regalloc_code2_BRANCH@22571 18797224-902f-48f8-a5cc-f745e15eee43
1999-03-02 16:12:08 +00:00

135 lines
3.2 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* The contents of this file are subject to the Netscape Public License
* Version 1.0 (the "NPL"); you may not use this file except in
* compliance with the NPL. You may obtain a copy of the NPL at
* http://www.mozilla.org/NPL/
*
* Software distributed under the NPL is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the NPL
* for the specific language governing rights and limitations under the
* NPL.
*
* The Initial Developer of this code under the NPL is Netscape
* Communications Corporation. Portions created by Netscape are
* Copyright (C) 1998 Netscape Communications Corporation. All Rights
* Reserved.
*/
#include "Fundamentals.h"
#include "BitSet.h"
// Return the next bit after index set to true or -1 if none.
//
Int32 BitSet::nextOne(Int32 pos) const
{
++pos;
if (pos < 0 || Uint32(pos) >= universeSize)
return -1;
Uint32 offset = getWordOffset(pos);
Uint8 index = getBitOffset(pos);
Word* ptr = &word[offset];
Word currentWord = *ptr++ >> index;
if (currentWord != Word(0)) {
while ((currentWord & Word(1)) == 0) {
++index;
currentWord >>= 1;
}
return (offset << nBitsInWordLog2) + index;
}
Word* limit = &word[getSizeInWords(universeSize)];
while (ptr < limit) {
++offset;
currentWord = *ptr++;
if (currentWord != Word(0)) {
index = 0;
while ((currentWord & Word(1)) == 0) {
++index;
currentWord >>= 1;
}
return (offset << nBitsInWordLog2) + index;
}
}
return -1;
}
// Return the next bit after index set to false or -1 if none.
//
Int32 BitSet::nextZero(Int32 pos) const
{
++pos;
if (pos < 0 || Uint32(pos) >= universeSize)
return -1;
Uint32 offset = getWordOffset(pos);
Uint8 index = getBitOffset(pos);
Word* ptr = &word[offset];
Word currentWord = *ptr++ >> index;
if (currentWord != Word(~0)) {
for (; index < nBitsInWord; ++index) {
if ((currentWord & Word(1)) == 0) {
Int32 ret = (offset << nBitsInWordLog2) + index;
return (Uint32(ret) < universeSize) ? ret : -1;
}
currentWord >>= 1;
}
}
Word* limit = &word[getSizeInWords(universeSize)];
while (ptr < limit) {
++offset;
currentWord = *ptr++;
if (currentWord != Word(~0)) {
for (index = 0; index < nBitsInWord; ++index) {
if ((currentWord & Word(1)) == 0) {
Int32 ret = (offset << nBitsInWordLog2) + index;
return (Uint32(ret) < universeSize) ? ret : -1;
}
currentWord >>= 1;
}
}
}
return -1;
}
#ifdef DEBUG_LOG
// Print the set.
//
void BitSet::printPretty(LogModuleObject log)
{
UT_OBJECTLOG(log, PR_LOG_ALWAYS, ("[ "));
for (Int32 i = firstOne(); i != -1; i = nextOne(i)) {
Int32 currentBit = i;
UT_OBJECTLOG(log, PR_LOG_ALWAYS, ("%d", currentBit));
Int32 nextBit = nextOne(currentBit);
if (nextBit != currentBit + 1) {
UT_OBJECTLOG(log, PR_LOG_ALWAYS, (" "));
continue;
}
while ((nextBit != -1) && (nextBit == (currentBit + 1))) {
currentBit = nextBit;
nextBit = nextOne(nextBit);
}
if (currentBit > (i+1))
UT_OBJECTLOG(log, PR_LOG_ALWAYS, ("-%d ", currentBit));
else
UT_OBJECTLOG(log, PR_LOG_ALWAYS, (" %d ", currentBit));
i = currentBit;
}
UT_OBJECTLOG(log, PR_LOG_ALWAYS, ("]\n"));
}
#endif // DEBUG_LOG