/*
* 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 {
static inline uint32_t
getWeightByte(uint32_t weight, int32_t idx) {
return getWeightTrail(weight, idx); /* same calculation */
}
static U_INLINE uint32_t
getWeightByte(uint32_t weight, int32_t index) {
return getWeightTrail(weight, index); /* same calculation */
}
