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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
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Add m-esr52 at 52.6.0
Diffstat (limited to 'intl/icu/source/common/bmpset.cpp')
-rw-r--r--intl/icu/source/common/bmpset.cpp727
1 files changed, 727 insertions, 0 deletions
diff --git a/intl/icu/source/common/bmpset.cpp b/intl/icu/source/common/bmpset.cpp
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+++ b/intl/icu/source/common/bmpset.cpp
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+// Copyright (C) 2016 and later: Unicode, Inc. and others.
+// License & terms of use: http://www.unicode.org/copyright.html
+/*
+******************************************************************************
+*
+* Copyright (C) 2007-2012, International Business Machines
+* Corporation and others. All Rights Reserved.
+*
+******************************************************************************
+* file name: bmpset.cpp
+* encoding: US-ASCII
+* tab size: 8 (not used)
+* indentation:4
+*
+* created on: 2007jan29
+* created by: Markus W. Scherer
+*/
+
+#include "unicode/utypes.h"
+#include "unicode/uniset.h"
+#include "unicode/utf8.h"
+#include "unicode/utf16.h"
+#include "cmemory.h"
+#include "bmpset.h"
+#include "uassert.h"
+
+U_NAMESPACE_BEGIN
+
+BMPSet::BMPSet(const int32_t *parentList, int32_t parentListLength) :
+ list(parentList), listLength(parentListLength) {
+ uprv_memset(asciiBytes, 0, sizeof(asciiBytes));
+ uprv_memset(table7FF, 0, sizeof(table7FF));
+ uprv_memset(bmpBlockBits, 0, sizeof(bmpBlockBits));
+
+ /*
+ * Set the list indexes for binary searches for
+ * U+0800, U+1000, U+2000, .., U+F000, U+10000.
+ * U+0800 is the first 3-byte-UTF-8 code point. Lower code points are
+ * looked up in the bit tables.
+ * The last pair of indexes is for finding supplementary code points.
+ */
+ list4kStarts[0]=findCodePoint(0x800, 0, listLength-1);
+ int32_t i;
+ for(i=1; i<=0x10; ++i) {
+ list4kStarts[i]=findCodePoint(i<<12, list4kStarts[i-1], listLength-1);
+ }
+ list4kStarts[0x11]=listLength-1;
+
+ initBits();
+ overrideIllegal();
+}
+
+BMPSet::BMPSet(const BMPSet &otherBMPSet, const int32_t *newParentList, int32_t newParentListLength) :
+ list(newParentList), listLength(newParentListLength) {
+ uprv_memcpy(asciiBytes, otherBMPSet.asciiBytes, sizeof(asciiBytes));
+ uprv_memcpy(table7FF, otherBMPSet.table7FF, sizeof(table7FF));
+ uprv_memcpy(bmpBlockBits, otherBMPSet.bmpBlockBits, sizeof(bmpBlockBits));
+ uprv_memcpy(list4kStarts, otherBMPSet.list4kStarts, sizeof(list4kStarts));
+}
+
+BMPSet::~BMPSet() {
+}
+
+/*
+ * Set bits in a bit rectangle in "vertical" bit organization.
+ * start<limit<=0x800
+ */
+static void set32x64Bits(uint32_t table[64], int32_t start, int32_t limit) {
+ U_ASSERT(start<limit);
+ U_ASSERT(limit<=0x800);
+
+ int32_t lead=start>>6; // Named for UTF-8 2-byte lead byte with upper 5 bits.
+ int32_t trail=start&0x3f; // Named for UTF-8 2-byte trail byte with lower 6 bits.
+
+ // Set one bit indicating an all-one block.
+ uint32_t bits=(uint32_t)1<<lead;
+ if((start+1)==limit) { // Single-character shortcut.
+ table[trail]|=bits;
+ return;
+ }
+
+ int32_t limitLead=limit>>6;
+ int32_t limitTrail=limit&0x3f;
+
+ if(lead==limitLead) {
+ // Partial vertical bit column.
+ while(trail<limitTrail) {
+ table[trail++]|=bits;
+ }
+ } else {
+ // Partial vertical bit column,
+ // followed by a bit rectangle,
+ // followed by another partial vertical bit column.
+ if(trail>0) {
+ do {
+ table[trail++]|=bits;
+ } while(trail<64);
+ ++lead;
+ }
+ if(lead<limitLead) {
+ bits=~((1<<lead)-1);
+ if(limitLead<0x20) {
+ bits&=(1<<limitLead)-1;
+ }
+ for(trail=0; trail<64; ++trail) {
+ table[trail]|=bits;
+ }
+ }
+ // limit<=0x800. If limit==0x800 then limitLead=32 and limitTrail=0.
+ // In that case, bits=1<<limitLead is undefined but the bits value
+ // is not used because trail<limitTrail is already false.
+ bits=(uint32_t)1<<((limitLead == 0x20) ? (limitLead - 1) : limitLead);
+ for(trail=0; trail<limitTrail; ++trail) {
+ table[trail]|=bits;
+ }
+ }
+}
+
+void BMPSet::initBits() {
+ UChar32 start, limit;
+ int32_t listIndex=0;
+
+ // Set asciiBytes[].
+ do {
+ start=list[listIndex++];
+ if(listIndex<listLength) {
+ limit=list[listIndex++];
+ } else {
+ limit=0x110000;
+ }
+ if(start>=0x80) {
+ break;
+ }
+ do {
+ asciiBytes[start++]=1;
+ } while(start<limit && start<0x80);
+ } while(limit<=0x80);
+
+ // Set table7FF[].
+ while(start<0x800) {
+ set32x64Bits(table7FF, start, limit<=0x800 ? limit : 0x800);
+ if(limit>0x800) {
+ start=0x800;
+ break;
+ }
+
+ start=list[listIndex++];
+ if(listIndex<listLength) {
+ limit=list[listIndex++];
+ } else {
+ limit=0x110000;
+ }
+ }
+
+ // Set bmpBlockBits[].
+ int32_t minStart=0x800;
+ while(start<0x10000) {
+ if(limit>0x10000) {
+ limit=0x10000;
+ }
+
+ if(start<minStart) {
+ start=minStart;
+ }
+ if(start<limit) { // Else: Another range entirely in a known mixed-value block.
+ if(start&0x3f) {
+ // Mixed-value block of 64 code points.
+ start>>=6;
+ bmpBlockBits[start&0x3f]|=0x10001<<(start>>6);
+ start=(start+1)<<6; // Round up to the next block boundary.
+ minStart=start; // Ignore further ranges in this block.
+ }
+ if(start<limit) {
+ if(start<(limit&~0x3f)) {
+ // Multiple all-ones blocks of 64 code points each.
+ set32x64Bits(bmpBlockBits, start>>6, limit>>6);
+ }
+
+ if(limit&0x3f) {
+ // Mixed-value block of 64 code points.
+ limit>>=6;
+ bmpBlockBits[limit&0x3f]|=0x10001<<(limit>>6);
+ limit=(limit+1)<<6; // Round up to the next block boundary.
+ minStart=limit; // Ignore further ranges in this block.
+ }
+ }
+ }
+
+ if(limit==0x10000) {
+ break;
+ }
+
+ start=list[listIndex++];
+ if(listIndex<listLength) {
+ limit=list[listIndex++];
+ } else {
+ limit=0x110000;
+ }
+ }
+}
+
+/*
+ * Override some bits and bytes to the result of contains(FFFD)
+ * for faster validity checking at runtime.
+ * No need to set 0 values where they were reset to 0 in the constructor
+ * and not modified by initBits().
+ * (asciiBytes[] trail bytes, table7FF[] 0..7F, bmpBlockBits[] 0..7FF)
+ * Need to set 0 values for surrogates D800..DFFF.
+ */
+void BMPSet::overrideIllegal() {
+ uint32_t bits, mask;
+ int32_t i;
+
+ if(containsSlow(0xfffd, list4kStarts[0xf], list4kStarts[0x10])) {
+ // contains(FFFD)==TRUE
+ for(i=0x80; i<0xc0; ++i) {
+ asciiBytes[i]=1;
+ }
+
+ bits=3; // Lead bytes 0xC0 and 0xC1.
+ for(i=0; i<64; ++i) {
+ table7FF[i]|=bits;
+ }
+
+ bits=1; // Lead byte 0xE0.
+ for(i=0; i<32; ++i) { // First half of 4k block.
+ bmpBlockBits[i]|=bits;
+ }
+
+ mask=~(0x10001<<0xd); // Lead byte 0xED.
+ bits=1<<0xd;
+ for(i=32; i<64; ++i) { // Second half of 4k block.
+ bmpBlockBits[i]=(bmpBlockBits[i]&mask)|bits;
+ }
+ } else {
+ // contains(FFFD)==FALSE
+ mask=~(0x10001<<0xd); // Lead byte 0xED.
+ for(i=32; i<64; ++i) { // Second half of 4k block.
+ bmpBlockBits[i]&=mask;
+ }
+ }
+}
+
+int32_t BMPSet::findCodePoint(UChar32 c, int32_t lo, int32_t hi) const {
+ /* Examples:
+ findCodePoint(c)
+ set list[] c=0 1 3 4 7 8
+ === ============== ===========
+ [] [110000] 0 0 0 0 0 0
+ [\u0000-\u0003] [0, 4, 110000] 1 1 1 2 2 2
+ [\u0004-\u0007] [4, 8, 110000] 0 0 0 1 1 2
+ [:Any:] [0, 110000] 1 1 1 1 1 1
+ */
+
+ // Return the smallest i such that c < list[i]. Assume
+ // list[len - 1] == HIGH and that c is legal (0..HIGH-1).
+ if (c < list[lo])
+ return lo;
+ // High runner test. c is often after the last range, so an
+ // initial check for this condition pays off.
+ if (lo >= hi || c >= list[hi-1])
+ return hi;
+ // invariant: c >= list[lo]
+ // invariant: c < list[hi]
+ for (;;) {
+ int32_t i = (lo + hi) >> 1;
+ if (i == lo) {
+ break; // Found!
+ } else if (c < list[i]) {
+ hi = i;
+ } else {
+ lo = i;
+ }
+ }
+ return hi;
+}
+
+UBool
+BMPSet::contains(UChar32 c) const {
+ if((uint32_t)c<=0x7f) {
+ return (UBool)asciiBytes[c];
+ } else if((uint32_t)c<=0x7ff) {
+ return (UBool)((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0);
+ } else if((uint32_t)c<0xd800 || (c>=0xe000 && c<=0xffff)) {
+ int lead=c>>12;
+ uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with the same bits 15..6
+ // are either in the set or not.
+ return (UBool)twoBits;
+ } else {
+ // Look up the code point in its 4k block of code points.
+ return containsSlow(c, list4kStarts[lead], list4kStarts[lead+1]);
+ }
+ } else if((uint32_t)c<=0x10ffff) {
+ // surrogate or supplementary code point
+ return containsSlow(c, list4kStarts[0xd], list4kStarts[0x11]);
+ } else {
+ // Out-of-range code points get FALSE, consistent with long-standing
+ // behavior of UnicodeSet::contains(c).
+ return FALSE;
+ }
+}
+
+/*
+ * Check for sufficient length for trail unit for each surrogate pair.
+ * Handle single surrogates as surrogate code points as usual in ICU.
+ */
+const UChar *
+BMPSet::span(const UChar *s, const UChar *limit, USetSpanCondition spanCondition) const {
+ UChar c, c2;
+
+ if(spanCondition) {
+ // span
+ do {
+ c=*s;
+ if(c<=0x7f) {
+ if(!asciiBytes[c]) {
+ break;
+ }
+ } else if(c<=0x7ff) {
+ if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))==0) {
+ break;
+ }
+ } else if(c<0xd800 || c>=0xe000) {
+ int lead=c>>12;
+ uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with the same bits 15..6
+ // are either in the set or not.
+ if(twoBits==0) {
+ break;
+ }
+ } else {
+ // Look up the code point in its 4k block of code points.
+ if(!containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
+ break;
+ }
+ }
+ } else if(c>=0xdc00 || (s+1)==limit || (c2=s[1])<0xdc00 || c2>=0xe000) {
+ // surrogate code point
+ if(!containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
+ break;
+ }
+ } else {
+ // surrogate pair
+ if(!containsSlow(U16_GET_SUPPLEMENTARY(c, c2), list4kStarts[0x10], list4kStarts[0x11])) {
+ break;
+ }
+ ++s;
+ }
+ } while(++s<limit);
+ } else {
+ // span not
+ do {
+ c=*s;
+ if(c<=0x7f) {
+ if(asciiBytes[c]) {
+ break;
+ }
+ } else if(c<=0x7ff) {
+ if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0) {
+ break;
+ }
+ } else if(c<0xd800 || c>=0xe000) {
+ int lead=c>>12;
+ uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with the same bits 15..6
+ // are either in the set or not.
+ if(twoBits!=0) {
+ break;
+ }
+ } else {
+ // Look up the code point in its 4k block of code points.
+ if(containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
+ break;
+ }
+ }
+ } else if(c>=0xdc00 || (s+1)==limit || (c2=s[1])<0xdc00 || c2>=0xe000) {
+ // surrogate code point
+ if(containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
+ break;
+ }
+ } else {
+ // surrogate pair
+ if(containsSlow(U16_GET_SUPPLEMENTARY(c, c2), list4kStarts[0x10], list4kStarts[0x11])) {
+ break;
+ }
+ ++s;
+ }
+ } while(++s<limit);
+ }
+ return s;
+}
+
+/* Symmetrical with span(). */
+const UChar *
+BMPSet::spanBack(const UChar *s, const UChar *limit, USetSpanCondition spanCondition) const {
+ UChar c, c2;
+
+ if(spanCondition) {
+ // span
+ for(;;) {
+ c=*(--limit);
+ if(c<=0x7f) {
+ if(!asciiBytes[c]) {
+ break;
+ }
+ } else if(c<=0x7ff) {
+ if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))==0) {
+ break;
+ }
+ } else if(c<0xd800 || c>=0xe000) {
+ int lead=c>>12;
+ uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with the same bits 15..6
+ // are either in the set or not.
+ if(twoBits==0) {
+ break;
+ }
+ } else {
+ // Look up the code point in its 4k block of code points.
+ if(!containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
+ break;
+ }
+ }
+ } else if(c<0xdc00 || s==limit || (c2=*(limit-1))<0xd800 || c2>=0xdc00) {
+ // surrogate code point
+ if(!containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
+ break;
+ }
+ } else {
+ // surrogate pair
+ if(!containsSlow(U16_GET_SUPPLEMENTARY(c2, c), list4kStarts[0x10], list4kStarts[0x11])) {
+ break;
+ }
+ --limit;
+ }
+ if(s==limit) {
+ return s;
+ }
+ }
+ } else {
+ // span not
+ for(;;) {
+ c=*(--limit);
+ if(c<=0x7f) {
+ if(asciiBytes[c]) {
+ break;
+ }
+ } else if(c<=0x7ff) {
+ if((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0) {
+ break;
+ }
+ } else if(c<0xd800 || c>=0xe000) {
+ int lead=c>>12;
+ uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with the same bits 15..6
+ // are either in the set or not.
+ if(twoBits!=0) {
+ break;
+ }
+ } else {
+ // Look up the code point in its 4k block of code points.
+ if(containsSlow(c, list4kStarts[lead], list4kStarts[lead+1])) {
+ break;
+ }
+ }
+ } else if(c<0xdc00 || s==limit || (c2=*(limit-1))<0xd800 || c2>=0xdc00) {
+ // surrogate code point
+ if(containsSlow(c, list4kStarts[0xd], list4kStarts[0xe])) {
+ break;
+ }
+ } else {
+ // surrogate pair
+ if(containsSlow(U16_GET_SUPPLEMENTARY(c2, c), list4kStarts[0x10], list4kStarts[0x11])) {
+ break;
+ }
+ --limit;
+ }
+ if(s==limit) {
+ return s;
+ }
+ }
+ }
+ return limit+1;
+}
+
+/*
+ * Precheck for sufficient trail bytes at end of string only once per span.
+ * Check validity.
+ */
+const uint8_t *
+BMPSet::spanUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const {
+ const uint8_t *limit=s+length;
+ uint8_t b=*s;
+ if((int8_t)b>=0) {
+ // Initial all-ASCII span.
+ if(spanCondition) {
+ do {
+ if(!asciiBytes[b] || ++s==limit) {
+ return s;
+ }
+ b=*s;
+ } while((int8_t)b>=0);
+ } else {
+ do {
+ if(asciiBytes[b] || ++s==limit) {
+ return s;
+ }
+ b=*s;
+ } while((int8_t)b>=0);
+ }
+ length=(int32_t)(limit-s);
+ }
+
+ if(spanCondition!=USET_SPAN_NOT_CONTAINED) {
+ spanCondition=USET_SPAN_CONTAINED; // Pin to 0/1 values.
+ }
+
+ const uint8_t *limit0=limit;
+
+ /*
+ * Make sure that the last 1/2/3/4-byte sequence before limit is complete
+ * or runs into a lead byte.
+ * In the span loop compare s with limit only once
+ * per multi-byte character.
+ *
+ * Give a trailing illegal sequence the same value as the result of contains(FFFD),
+ * including it if that is part of the span, otherwise set limit0 to before
+ * the truncated sequence.
+ */
+ b=*(limit-1);
+ if((int8_t)b<0) {
+ // b>=0x80: lead or trail byte
+ if(b<0xc0) {
+ // single trail byte, check for preceding 3- or 4-byte lead byte
+ if(length>=2 && (b=*(limit-2))>=0xe0) {
+ limit-=2;
+ if(asciiBytes[0x80]!=spanCondition) {
+ limit0=limit;
+ }
+ } else if(b<0xc0 && b>=0x80 && length>=3 && (b=*(limit-3))>=0xf0) {
+ // 4-byte lead byte with only two trail bytes
+ limit-=3;
+ if(asciiBytes[0x80]!=spanCondition) {
+ limit0=limit;
+ }
+ }
+ } else {
+ // lead byte with no trail bytes
+ --limit;
+ if(asciiBytes[0x80]!=spanCondition) {
+ limit0=limit;
+ }
+ }
+ }
+
+ uint8_t t1, t2, t3;
+
+ while(s<limit) {
+ b=*s;
+ if(b<0xc0) {
+ // ASCII; or trail bytes with the result of contains(FFFD).
+ if(spanCondition) {
+ do {
+ if(!asciiBytes[b]) {
+ return s;
+ } else if(++s==limit) {
+ return limit0;
+ }
+ b=*s;
+ } while(b<0xc0);
+ } else {
+ do {
+ if(asciiBytes[b]) {
+ return s;
+ } else if(++s==limit) {
+ return limit0;
+ }
+ b=*s;
+ } while(b<0xc0);
+ }
+ }
+ ++s; // Advance past the lead byte.
+ if(b>=0xe0) {
+ if(b<0xf0) {
+ if( /* handle U+0000..U+FFFF inline */
+ (t1=(uint8_t)(s[0]-0x80)) <= 0x3f &&
+ (t2=(uint8_t)(s[1]-0x80)) <= 0x3f
+ ) {
+ b&=0xf;
+ uint32_t twoBits=(bmpBlockBits[t1]>>b)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with this lead byte and middle trail byte
+ // are either in the set or not.
+ if(twoBits!=(uint32_t)spanCondition) {
+ return s-1;
+ }
+ } else {
+ // Look up the code point in its 4k block of code points.
+ UChar32 c=(b<<12)|(t1<<6)|t2;
+ if(containsSlow(c, list4kStarts[b], list4kStarts[b+1]) != spanCondition) {
+ return s-1;
+ }
+ }
+ s+=2;
+ continue;
+ }
+ } else if( /* handle U+10000..U+10FFFF inline */
+ (t1=(uint8_t)(s[0]-0x80)) <= 0x3f &&
+ (t2=(uint8_t)(s[1]-0x80)) <= 0x3f &&
+ (t3=(uint8_t)(s[2]-0x80)) <= 0x3f
+ ) {
+ // Give an illegal sequence the same value as the result of contains(FFFD).
+ UChar32 c=((UChar32)(b-0xf0)<<18)|((UChar32)t1<<12)|(t2<<6)|t3;
+ if( ( (0x10000<=c && c<=0x10ffff) ?
+ containsSlow(c, list4kStarts[0x10], list4kStarts[0x11]) :
+ asciiBytes[0x80]
+ ) != spanCondition
+ ) {
+ return s-1;
+ }
+ s+=3;
+ continue;
+ }
+ } else /* 0xc0<=b<0xe0 */ {
+ if( /* handle U+0000..U+07FF inline */
+ (t1=(uint8_t)(*s-0x80)) <= 0x3f
+ ) {
+ if((USetSpanCondition)((table7FF[t1]&((uint32_t)1<<(b&0x1f)))!=0) != spanCondition) {
+ return s-1;
+ }
+ ++s;
+ continue;
+ }
+ }
+
+ // Give an illegal sequence the same value as the result of contains(FFFD).
+ // Handle each byte of an illegal sequence separately to simplify the code;
+ // no need to optimize error handling.
+ if(asciiBytes[0x80]!=spanCondition) {
+ return s-1;
+ }
+ }
+
+ return limit0;
+}
+
+/*
+ * While going backwards through UTF-8 optimize only for ASCII.
+ * Unlike UTF-16, UTF-8 is not forward-backward symmetrical, that is, it is not
+ * possible to tell from the last byte in a multi-byte sequence how many
+ * preceding bytes there should be. Therefore, going backwards through UTF-8
+ * is much harder than going forward.
+ */
+int32_t
+BMPSet::spanBackUTF8(const uint8_t *s, int32_t length, USetSpanCondition spanCondition) const {
+ if(spanCondition!=USET_SPAN_NOT_CONTAINED) {
+ spanCondition=USET_SPAN_CONTAINED; // Pin to 0/1 values.
+ }
+
+ uint8_t b;
+
+ do {
+ b=s[--length];
+ if((int8_t)b>=0) {
+ // ASCII sub-span
+ if(spanCondition) {
+ do {
+ if(!asciiBytes[b]) {
+ return length+1;
+ } else if(length==0) {
+ return 0;
+ }
+ b=s[--length];
+ } while((int8_t)b>=0);
+ } else {
+ do {
+ if(asciiBytes[b]) {
+ return length+1;
+ } else if(length==0) {
+ return 0;
+ }
+ b=s[--length];
+ } while((int8_t)b>=0);
+ }
+ }
+
+ int32_t prev=length;
+ UChar32 c;
+ // trail byte: collect a multi-byte character
+ // (or lead byte in last-trail position)
+ c=utf8_prevCharSafeBody(s, 0, &length, b, -3);
+ // c is a valid code point, not ASCII, not a surrogate
+ if(c<=0x7ff) {
+ if((USetSpanCondition)((table7FF[c&0x3f]&((uint32_t)1<<(c>>6)))!=0) != spanCondition) {
+ return prev+1;
+ }
+ } else if(c<=0xffff) {
+ int lead=c>>12;
+ uint32_t twoBits=(bmpBlockBits[(c>>6)&0x3f]>>lead)&0x10001;
+ if(twoBits<=1) {
+ // All 64 code points with the same bits 15..6
+ // are either in the set or not.
+ if(twoBits!=(uint32_t)spanCondition) {
+ return prev+1;
+ }
+ } else {
+ // Look up the code point in its 4k block of code points.
+ if(containsSlow(c, list4kStarts[lead], list4kStarts[lead+1]) != spanCondition) {
+ return prev+1;
+ }
+ }
+ } else {
+ if(containsSlow(c, list4kStarts[0x10], list4kStarts[0x11]) != spanCondition) {
+ return prev+1;
+ }
+ }
+ } while(length>0);
+ return 0;
+}
+
+U_NAMESPACE_END