/*
*******************************************************************************
*
* Copyright (C) 1999-2010, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: ucol_wgt.c
* encoding: US-ASCII
* tab size: 8 (not used)
* indentation:4
*
* created on: 2001mar08
* created by: Markus W. Scherer
*
* This file contains code for allocating n collation element weights
* between two exclusive limits.
* It is used only internally by ucol_bld.
*/
#include "unicode/utypes.h"
#if !UCONFIG_NO_COLLATION
#include "ucol_imp.h"
#include "ucol_wgt.h"
#include "cmemory.h"
#include "uarrsort.h"
#ifdef UCOL_DEBUG
# include <stdio.h>
#endif
/* collation element weight allocation -------------------------------------- */
/* helper functions for CE weights */
static U_INLINE int32_t
lengthOfWeight(uint32_t weight) {
if((weight&0xffffff)==0) {
return 1;
} else if((weight&0xffff)==0) {
return 2;
} else if((weight&0xff)==0) {
return 3;
} else {
return 4;
}
}
static U_INLINE uint32_t
getWeightTrail(uint32_t weight, int32_t length) {
return (uint32_t)(weight>>(8*(4-length)))&0xff;
}
static U_INLINE uint32_t
setWeightTrail(uint32_t weight, int32_t length, uint32_t trail) {
length=8*(4-length);
return (uint32_t)((weight&(0xffffff00<<length))|(trail<<length));
}
static U_INLINE uint32_t
getWeightByte(uint32_t weight, int32_t idx) {
return getWeightTrail(weight, idx); /* same calculation */
}
static U_INLINE uint32_t
setWeightByte(uint32_t weight, int32_t idx, uint32_t byte) {
uint32_t mask; /* 0xffffffff except a 00 "hole" for the index-th byte */
idx*=8;
mask=((uint32_t)0xffffffff)>>idx;
idx=32-idx;
mask|=0xffffff00<<idx;
return (uint32_t)((weight&mask)|(byte<<idx));
}
static U_INLINE uint32_t
truncateWeight(uint32_t weight, int32_t length) {
return (uint32_t)(weight&(0xffffffff<<(8*(4-length))));
}
static U_INLINE uint32_t
incWeightTrail(uint32_t weight, int32_t length) {
return (uint32_t)(weight+(1UL<<(8*(4-length))));
}
static U_INLINE uint32_t
decWeightTrail(uint32_t weight, int32_t length) {
return (uint32_t)(weight-(1UL<<(8*(4-length))));
}
static U_INLINE uint32_t
incWeight(uint32_t weight, int32_t length, uint32_t maxByte) {
uint32_t byte;
for(;;) {
byte=getWeightByte(weight, length);
if(byte<maxByte) {
return setWeightByte(weight, length, byte+1);
} else {
/* roll over, set this byte to UCOL_BYTE_FIRST_TAILORED and increment the previous one */
weight=setWeightByte(weight, length, UCOL_BYTE_FIRST_TAILORED);
--length;
}
}
}
static U_INLINE int32_t
lengthenRange(WeightRange *range, uint32_t maxByte, uint32_t countBytes) {
int32_t length;
length=range->length2+1;
range->start=setWeightTrail(range->start, length, UCOL_BYTE_FIRST_TAILORED);
range->end=setWeightTrail(range->end, length, maxByte);
range->count2*=countBytes;
range->length2=length;
return length;
}
/* for uprv_sortArray: sort ranges in weight order */
static int32_t U_CALLCONV
compareRanges(const void *context, const void *left, const void *right) {
uint32_t l, r;
l=((const WeightRange *)left)->start;
r=((const WeightRange *)right)->start;
if(l<r) {
return -1;
} else if(l>r) {
return 1;
} else {
return 0;
}
}
/*
* take two CE weights and calculate the
* possible ranges of weights between the two limits, excluding them
* for weights with up to 4 bytes there are up to 2*4-1=7 ranges
*/
static U_INLINE int32_t
getWeightRanges(uint32_t lowerLimit, uint32_t upperLimit,
uint32_t maxByte, uint32_t countBytes,
WeightRange ranges[7]) {
WeightRange lower[5], middle, upper[5]; /* [0] and [1] are not used - this simplifies indexing */
uint32_t weight, trail;
int32_t length, lowerLength, upperLength, rangeCount;
/* assume that both lowerLimit & upperLimit are not 0 */
/* get the lengths of the limits */
lowerLength=lengthOfWeight(lowerLimit);
upperLength=lengthOfWeight(upperLimit);
#ifdef UCOL_DEBUG
printf("length of lower limit 0x%08lx is %ld\n", lowerLimit, lowerLength);
printf("length of upper limit 0x%08lx is %ld\n", upperLimit, upperLength);
#endif
if(lowerLimit>=upperLimit) {
#ifdef UCOL_DEBUG
printf("error: no space between lower & upper limits\n");
#endif
return 0;
}
/* check that neither is a prefix of the other */
if(lowerLength<upperLength) {
if(lowerLimit==truncateWeight(upperLimit, lowerLength)) {
#ifdef UCOL_DEBUG
printf("error: lower limit 0x%08lx is a prefix of upper limit 0x%08lx\n", lowerLimit, upperLimit);
#endif
return 0;
}
}
/* if the upper limit is a prefix of the lower limit then the earlier test lowerLimit>=upperLimit has caught it */
/* reset local variables */
uprv_memset(lower, 0, sizeof(lower));
uprv_memset(&middle, 0, sizeof(middle));
uprv_memset(upper, 0, sizeof(upper));
/*
* With the limit lengths of 1..4, there are up to 7 ranges for allocation:
* range minimum length
* lower[4] 4
* lower[3] 3
* lower[2] 2
* middle 1
* upper[2] 2
* upper[3] 3
* upper[4] 4
*
* We are now going to calculate up to 7 ranges.
* Some of them will typically overlap, so we will then have to merge and eliminate ranges.
*/
weight=lowerLimit;
for(length=lowerLength; length>=2; --length) {
trail=getWeightTrail(weight, length);
if(trail<maxByte) {
lower[length].start=incWeightTrail(weight, length);
lower[length].end=setWeightTrail(weight, length, maxByte);
lower[length].length=length;
lower[length].count=maxByte-trail;
}
weight=truncateWeight(weight, length-1);
}
middle.start=incWeightTrail(weight, 1);
weight=upperLimit;
for(length=upperLength; length>=2; --length) {
trail=getWeightTrail(weight, length);
if(trail>UCOL_BYTE_FIRST_TAILORED) {
upper[length].start=setWeightTrail(weight, length, UCOL_BYTE_FIRST_TAILORED);
upper[length].end=decWeightTrail(weight, length);
upper[length].length=length;
upper[length].count=trail-UCOL_BYTE_FIRST_TAILORED;
}
weight=truncateWeight(weight, length-1);
}
middle.end=decWeightTrail(weight, 1);
/* set the middle range */
middle.length=1;
if(middle.end>=middle.start) {
middle.count=(int32_t)((middle.end-middle.start)>>24)+1;
} else {
/* eliminate overlaps */
uint32_t start, end;
/* remove the middle range */
middle.count=0;
/* reduce or remove the lower ranges that go beyond upperLimit */
for(length=4; length>=2; --length) {
if(lower[length].count>0 && upper[length].count>0) {
start=upper[length].start;
end=lower[length].end;
if(end>=start || incWeight(end, length, maxByte)==start) {
/* lower and upper ranges collide or are directly adjacent: merge these two and remove all shorter ranges */
start=lower[length].start;
end=lower[length].end=upper[length].end;
/*
* merging directly adjacent ranges needs to subtract the 0/1 gaps in between;
* it may result in a range with count>countBytes
*/
lower[length].count=
(int32_t)(getWeightTrail(end, length)-getWeightTrail(start, length)+1+
countBytes*(getWeightByte(end, length-1)-getWeightByte(start, length-1)));
upper[length].count=0;
while(--length>=2) {
lower[length].count=upper[length].count=0;
}
break;
}
}
}
}
#ifdef UCOL_DEBUG
/* print ranges */
for(length=4; length>=2; --length) {
if(lower[length].count>0) {
printf("lower[%ld] .start=0x%08lx .end=0x%08lx .count=%ld\n", length, lower[length].start, lower[length].end, lower[length].count);
}
}
if(middle.count>0) {
printf("middle .start=0x%08lx .end=0x%08lx .count=%ld\n", middle.start, middle.end, middle.count);
}
for(length=2; length<=4; ++length) {
if(upper[length].count>0) {
printf("upper[%ld] .start=0x%08lx .end=0x%08lx .count=%ld\n", length, upper[length].start, upper[length].end, upper[length].count);
}
}
#endif
/* copy the ranges, shortest first, into the result array */
rangeCount=0;
if(middle.count>0) {
uprv_memcpy(ranges, &middle, sizeof(WeightRange));
rangeCount=1;
}
for(length=2; length<=4; ++length) {
/* copy upper first so that later the middle range is more likely the first one to use */
if(upper[length].count>0) {
uprv_memcpy(ranges+rangeCount, upper+length, sizeof(WeightRange));
++rangeCount;
}
if(lower[length].count>0) {
uprv_memcpy(ranges+rangeCount, lower+length, sizeof(WeightRange));
++rangeCount;
}
}
return rangeCount;
}
/*
* call getWeightRanges and then determine heuristically
* which ranges to use for a given number of weights between (excluding)
* two limits
*/
U_CFUNC int32_t
ucol_allocWeights(uint32_t lowerLimit, uint32_t upperLimit,
uint32_t n,
uint32_t maxByte,
WeightRange ranges[7]) {
/* number of usable byte values 3..maxByte */
uint32_t countBytes=maxByte-UCOL_BYTE_FIRST_TAILORED+1;
uint32_t lengthCounts[6]; /* [0] unused, [5] to make index checks unnecessary */
uint32_t maxCount;
int32_t i, rangeCount, minLength/*, maxLength*/;
/* countBytes to the power of index */
uint32_t powers[5];
/* gcc requires explicit initialization */
powers[0] = 1;
powers[1] = countBytes;
powers[2] = countBytes*countBytes;
powers[3] = countBytes*countBytes*countBytes;
powers[4] = countBytes*countBytes*countBytes*countBytes;
#ifdef UCOL_DEBUG
puts("");
#endif
rangeCount=getWeightRanges(lowerLimit, upperLimit, maxByte, countBytes, ranges);
if(rangeCount<=0) {
#ifdef UCOL_DEBUG
printf("error: unable to get Weight ranges\n");
#endif
return 0;
}
/* what is the maximum number of weights with these ranges? */
maxCount=0;
for(i=0; i<rangeCount; ++i) {
maxCount+=(uint32_t)ranges[i].count*powers[4-ranges[i].length];
}
if(maxCount>=n) {
#ifdef UCOL_DEBUG
printf("the maximum number of %lu weights is sufficient for n=%lu\n", maxCount, n);
#endif
} else {
#ifdef UCOL_DEBUG
printf("error: the maximum number of %lu weights is insufficient for n=%lu\n", maxCount, n);
#endif
return 0;
}
/* set the length2 and count2 fields */
for(i=0; i<rangeCount; ++i) {
ranges[i].length2=ranges[i].length;
ranges[i].count2=(uint32_t)ranges[i].count;
}
/* try until we find suitably large ranges */
for(;;) {
/* get the smallest number of bytes in a range */
minLength=ranges[0].length2;
/* sum up the number of elements that fit into ranges of each byte length */
uprv_memset(lengthCounts, 0, sizeof(lengthCounts));
for(i=0; i<rangeCount; ++i) {
lengthCounts[ranges[i].length2]+=ranges[i].count2;
}
/* now try to allocate n elements in the available short ranges */
if(n<=(lengthCounts[minLength]+lengthCounts[minLength+1])) {
/* trivial cases, use the first few ranges */
maxCount=0;
rangeCount=0;
do {
maxCount+=ranges[rangeCount].count2;
++rangeCount;
} while(n>maxCount);
#ifdef UCOL_DEBUG
printf("take first %ld ranges\n", rangeCount);
#endif
break;
} else if(n<=ranges[0].count2*countBytes) {
/* easy case, just make this one range large enough by lengthening it once more, possibly split it */
uint32_t count1, count2, power_1, power;
/*maxLength=minLength+1;*/
/* calculate how to split the range between maxLength-1 (count1) and maxLength (count2) */
power_1=powers[minLength-ranges[0].length];
power=power_1*countBytes;
count2=(n+power-1)/power;
count1=ranges[0].count-count2;
/* split the range */
#ifdef UCOL_DEBUG
printf("split the first range %ld:%ld\n", count1, count2);
#endif
if(count1<1) {
rangeCount=1;
/* lengthen the entire range to maxLength */
lengthenRange(ranges, maxByte, countBytes);
} else {
/* really split the range */
uint32_t byte;
/* create a new range with the end and initial and current length of the old one */
rangeCount=2;
ranges[1].end=ranges[0].end;
ranges[1].length=ranges[0].length;
ranges[1].length2=minLength;
/* set the end of the first range according to count1 */
i=ranges[0].length;
byte=getWeightByte(ranges[0].start, i)+count1-1;
/*
* ranges[0].count and count1 may be >countBytes
* from merging adjacent ranges;
* byte>maxByte is possible
*/
if(byte<=maxByte) {
ranges[0].end=setWeightByte(ranges[0].start, i, byte);
} else /* byte>maxByte */ {
ranges[0].end=setWeightByte(incWeight(ranges[0].start, i-1, maxByte), i, byte-countBytes);
}
/* set the bytes in the end weight at length+1..length2 to maxByte */
byte=(maxByte<<24)|(maxByte<<16)|(maxByte<<8)|maxByte; /* this used to be 0xffffffff */
ranges[0].end=truncateWeight(ranges[0].end, i)|
((byte>>(8*i))&(byte<<(8*(4-minLength))));
/* set the start of the second range to immediately follow the end of the first one */
ranges[1].start=incWeight(ranges[0].end, minLength, maxByte);
/* set the count values (informational) */
ranges[0].count=count1;
ranges[1].count=count2;
ranges[0].count2=count1*power_1;
ranges[1].count2=count2*power_1; /* will be *countBytes when lengthened */
/* lengthen the second range to maxLength */
lengthenRange(ranges+1, maxByte, countBytes);
}
break;
}
/* no good match, lengthen all minLength ranges and iterate */
#ifdef UCOL_DEBUG
printf("lengthen the short ranges from %ld bytes to %ld and iterate\n", minLength, minLength+1);
#endif
for(i=0; ranges[i].length2==minLength; ++i) {
lengthenRange(ranges+i, maxByte, countBytes);
}
}
if(rangeCount>1) {
/* sort the ranges by weight values */
UErrorCode errorCode=U_ZERO_ERROR;
uprv_sortArray(ranges, rangeCount, sizeof(WeightRange), compareRanges, NULL, FALSE, &errorCode);
/* ignore error code: we know that the internal sort function will not fail here */
}
#ifdef UCOL_DEBUG
puts("final ranges:");
for(i=0; i<rangeCount; ++i) {
printf("ranges[%ld] .start=0x%08lx .end=0x%08lx .length=%ld .length2=%ld .count=%ld .count2=%lu\n",
i, ranges[i].start, ranges[i].end, ranges[i].length, ranges[i].length2, ranges[i].count, ranges[i].count2);
}
#endif
/* set maxByte in ranges[0] for ucol_nextWeight() */
ranges[0].count=maxByte;
return rangeCount;
}
/*
* given a set of ranges calculated by ucol_allocWeights(),
* iterate through the weights
*/
U_CFUNC uint32_t
ucol_nextWeight(WeightRange ranges[], int32_t *pRangeCount) {
if(*pRangeCount<=0) {
return 0xffffffff;
} else {
uint32_t weight, maxByte;
/* get maxByte from the .count field */
maxByte=ranges[0].count;
/* get the next weight */
weight=ranges[0].start;
if(weight==ranges[0].end) {
/* this range is finished, remove it and move the following ones up */
if(--*pRangeCount>0) {
uprv_memmove(ranges, ranges+1, *pRangeCount*sizeof(WeightRange));
ranges[0].count=maxByte; /* keep maxByte in ranges[0] */
}
} else {
/* increment the weight for the next value */
ranges[0].start=incWeight(weight, ranges[0].length2, maxByte);
}
return weight;
}
}
#ifdef UCOL_DEBUG
static void
testAlloc(uint32_t lowerLimit, uint32_t upperLimit, uint32_t n, UBool enumerate) {
WeightRange ranges[8];
int32_t rangeCount;
rangeCount=ucol_allocWeights(lowerLimit, upperLimit, n, ranges);
if(enumerate) {
uint32_t weight;
while(n>0) {
weight=ucol_nextWeight(ranges, &rangeCount);
if(weight==0xffffffff) {
printf("error: 0xffffffff with %lu more weights to go\n", n);
break;
}
printf(" 0x%08lx\n", weight);
--n;
}
}
}
extern int
main(int argc, const char *argv[]) {
#if 0
#endif
testAlloc(0x364214fc, 0x44b87d23, 5, FALSE);
testAlloc(0x36421500, 0x44b87d23, 5, FALSE);
testAlloc(0x36421500, 0x44b87d23, 20, FALSE);
testAlloc(0x36421500, 0x44b87d23, 13700, FALSE);
testAlloc(0x36421500, 0x38b87d23, 1, FALSE);
testAlloc(0x36421500, 0x38b87d23, 20, FALSE);
testAlloc(0x36421500, 0x38b87d23, 200, TRUE);
testAlloc(0x36421500, 0x38b87d23, 13700, FALSE);
testAlloc(0x36421500, 0x37b87d23, 13700, FALSE);
testAlloc(0x36ef1500, 0x37b87d23, 13700, FALSE);
testAlloc(0x36421500, 0x36b87d23, 13700, FALSE);
testAlloc(0x36b87122, 0x36b87d23, 13700, FALSE);
testAlloc(0x49000000, 0x4a600000, 13700, FALSE);
testAlloc(0x9fffffff, 0xd0000000, 13700, FALSE);
testAlloc(0x9fffffff, 0xd0000000, 67400, FALSE);
testAlloc(0x9fffffff, 0xa0030000, 67400, FALSE);
testAlloc(0x9fffffff, 0xa0030000, 40000, FALSE);
testAlloc(0xa0000000, 0xa0030000, 40000, FALSE);
testAlloc(0xa0031100, 0xa0030000, 40000, FALSE);
#if 0
#endif
return 0;
}
#endif
#endif /* #if !UCONFIG_NO_COLLATION */