../deps/icu-small/source/common/normalizer2impl.cpp

Bug Summary

File:	out/../deps/icu-small/source/common/normalizer2impl.cpp
Warning:	line 539, column 14 Dereference of null pointer
Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-unknown-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name normalizer2impl.cpp -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -pic-is-pie -mframe-pointer=all -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/home/maurizio/node-v18.6.0/out -resource-dir /usr/local/lib/clang/16.0.0 -D V8_DEPRECATION_WARNINGS -D V8_IMMINENT_DEPRECATION_WARNINGS -D _GLIBCXX_USE_CXX11_ABI=1 -D NODE_OPENSSL_CONF_NAME=nodejs_conf -D NODE_OPENSSL_HAS_QUIC -D __STDC_FORMAT_MACROS -D OPENSSL_NO_PINSHARED -D OPENSSL_THREADS -D U_COMMON_IMPLEMENTATION=1 -D U_ATTRIBUTE_DEPRECATED= -D _CRT_SECURE_NO_DEPRECATE= -D U_STATIC_IMPLEMENTATION=1 -D UCONFIG_NO_SERVICE=1 -D U_ENABLE_DYLOAD=0 -D U_HAVE_STD_STRING=1 -D UCONFIG_NO_BREAK_ITERATION=0 -I ../deps/icu-small/source/common -internal-isystem /usr/lib/gcc/x86_64-redhat-linux/8/../../../../include/c++/8 -internal-isystem /usr/lib/gcc/x86_64-redhat-linux/8/../../../../include/c++/8/x86_64-redhat-linux -internal-isystem /usr/lib/gcc/x86_64-redhat-linux/8/../../../../include/c++/8/backward -internal-isystem /usr/local/lib/clang/16.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-redhat-linux/8/../../../../x86_64-redhat-linux/include -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-unused-parameter -Wno-deprecated-declarations -Wno-strict-aliasing -std=gnu++17 -fdeprecated-macro -fdebug-compilation-dir=/home/maurizio/node-v18.6.0/out -ferror-limit 19 -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-08-22-142216-507842-1 -x c++ ../deps/icu-small/source/common/normalizer2impl.cpp
1// © 2016 and later: Unicode, Inc. and others.
2// License & terms of use: http://www.unicode.org/copyright.html
3/*
4*******************************************************************************
5*
6*   Copyright (C) 2009-2014, International Business Machines
7*   Corporation and others.  All Rights Reserved.
8*
9*******************************************************************************
10*   file name:  normalizer2impl.cpp
11*   encoding:   UTF-8
12*   tab size:   8 (not used)
13*   indentation:4
14*
15*   created on: 2009nov22
16*   created by: Markus W. Scherer
17*/

19// #define UCPTRIE_DEBUG

21#include "unicode/utypes.h"

23#if !UCONFIG_NO_NORMALIZATION0

25#include "unicode/bytestream.h"
26#include "unicode/edits.h"
27#include "unicode/normalizer2.h"
28#include "unicode/stringoptions.h"
29#include "unicode/ucptrie.h"
30#include "unicode/udata.h"
31#include "unicode/umutablecptrie.h"
32#include "unicode/ustring.h"
33#include "unicode/utf16.h"
34#include "unicode/utf8.h"
35#include "bytesinkutil.h"
36#include "cmemory.h"
37#include "mutex.h"
38#include "normalizer2impl.h"
39#include "putilimp.h"
40#include "uassert.h"
41#include "ucptrie_impl.h"
42#include "uset_imp.h"
43#include "uvector.h"

45U_NAMESPACE_BEGINnamespace icu_71 {

47namespace {

49/**
* UTF-8 lead byte for minNoMaybeCP.
* Can be lower than the actual lead byte for c.
* Typically U+0300 for NFC/NFD, U+00A0 for NFKC/NFKD, U+0041 for NFKC_Casefold.
*/
54inline uint8_t leadByteForCP(UChar32 c) {
  if (c <= 0x7f) {
      return (uint8_t)c;
  } else if (c <= 0x7ff) {
      return (uint8_t)(0xc0+(c>>6));
  } else {
      // Should not occur because ccc(U+0300)!=0.
      return 0xe0;
  }
63}

65/**
* Returns the code point from one single well-formed UTF-8 byte sequence
* between cpStart and cpLimit.
*
* Trie UTF-8 macros do not assemble whole code points (for efficiency).
* When we do need the code point, we call this function.
* We should not need it for normalization-inert data (norm16==0).
* Illegal sequences yield the error value norm16==0 just like real normalization-inert code points.
*/
74UChar32 codePointFromValidUTF8(const uint8_t *cpStart, const uint8_t *cpLimit) {
  // Similar to U8_NEXT_UNSAFE(s, i, c).
  U_ASSERT(cpStart < cpLimit)(void)0;
  uint8_t c = *cpStart;
  switch(cpLimit-cpStart) {
  case 1:
      return c;
  case 2:
      return ((c&0x1f)<<6) | (cpStart[1]&0x3f);
  case 3:
      // no need for (c&0xf) because the upper bits are truncated after <<12 in the cast to (UChar)
      return (UChar)((c<<12) | ((cpStart[1]&0x3f)<<6) | (cpStart[2]&0x3f));
  case 4:
      return ((c&7)<<18) | ((cpStart[1]&0x3f)<<12) | ((cpStart[2]&0x3f)<<6) | (cpStart[3]&0x3f);
  default:
      UPRV_UNREACHABLE_EXITabort();  // Should not occur.
  }
91}

93/**
* Returns the last code point in [start, p[ if it is valid and in U+1000..U+D7FF.
* Otherwise returns a negative value.
*/
97UChar32 previousHangulOrJamo(const uint8_t *start, const uint8_t *p) {
  if ((p - start) >= 3) {
      p -= 3;
      uint8_t l = *p;
      uint8_t t1, t2;
      if (0xe1 <= l && l <= 0xed &&
              (t1 = (uint8_t)(p[1] - 0x80)) <= 0x3f &&
              (t2 = (uint8_t)(p[2] - 0x80)) <= 0x3f &&
              (l < 0xed || t1 <= 0x1f)) {
          return ((l & 0xf) << 12) | (t1 << 6) | t2;
      }
  }
  return U_SENTINEL(-1);
110}

112/**
* Returns the offset from the Jamo T base if [src, limit[ starts with a single Jamo T code point.
* Otherwise returns a negative value.
*/
116int32_t getJamoTMinusBase(const uint8_t *src, const uint8_t *limit) {
  // Jamo T: E1 86 A8..E1 87 82
  if ((limit - src) >= 3 && *src == 0xe1) {
      if (src[1] == 0x86) {
          uint8_t t = src[2];
          // The first Jamo T is U+11A8 but JAMO_T_BASE is 11A7.
          // Offset 0 does not correspond to any conjoining Jamo.
          if (0xa8 <= t && t <= 0xbf) {
              return t - 0xa7;
          }
      } else if (src[1] == 0x87) {
          uint8_t t = src[2];
          if ((int8_t)t <= (int8_t)0x82u) {
              return t - (0xa7 - 0x40);
          }
      }
  }
  return -1;
134}

136void
137appendCodePointDelta(const uint8_t *cpStart, const uint8_t *cpLimit, int32_t delta,
                   ByteSink &sink, Edits *edits) {
  char buffer[U8_MAX_LENGTH4];
  int32_t length;
  int32_t cpLength = (int32_t)(cpLimit - cpStart);
  if (cpLength == 1) {
      // The builder makes ASCII map to ASCII.
      buffer[0] = (uint8_t)(*cpStart + delta);
      length = 1;
  } else {
      int32_t trail = *(cpLimit-1) + delta;
      if (0x80 <= trail && trail <= 0xbf) {
          // The delta only changes the last trail byte.
          --cpLimit;
          length = 0;
          do { buffer[length++] = *cpStart++; } while (cpStart < cpLimit);
          buffer[length++] = (uint8_t)trail;
      } else {
          // Decode the code point, add the delta, re-encode.
          UChar32 c = codePointFromValidUTF8(cpStart, cpLimit) + delta;
          length = 0;
          U8_APPEND_UNSAFE(buffer, length, c)do { uint32_t __uc=(c); if(__uc<=0x7f) { (buffer)[(length)
++]=(uint8_t)__uc; } else { if(__uc<=0x7ff) { (buffer)[(length
)++]=(uint8_t)((__uc>>6)|0xc0); } else { if(__uc<=0xffff
) { (buffer)[(length)++]=(uint8_t)((__uc>>12)|0xe0); } else
 { (buffer)[(length)++]=(uint8_t)((__uc>>18)|0xf0); (buffer
)[(length)++]=(uint8_t)(((__uc>>12)&0x3f)|0x80); } (
buffer)[(length)++]=(uint8_t)(((__uc>>6)&0x3f)|0x80
); } (buffer)[(length)++]=(uint8_t)((__uc&0x3f)|0x80); } }
 while (false);
      }
  }
  if (edits != nullptr) {
      edits->addReplace(cpLength, length);
  }
  sink.Append(buffer, length);
165}

167}  // namespace

169// ReorderingBuffer -------------------------------------------------------- ***

171ReorderingBuffer::ReorderingBuffer(const Normalizer2Impl &ni, UnicodeString &dest,
                                 UErrorCode &errorCode) :
      impl(ni), str(dest),
      start(str.getBuffer(8)), reorderStart(start), limit(start),
      remainingCapacity(str.getCapacity()), lastCC(0) {
  if (start == nullptr && U_SUCCESS(errorCode)) {
      // getBuffer() already did str.setToBogus()
      errorCode = U_MEMORY_ALLOCATION_ERROR;
  }
180}

182UBool ReorderingBuffer::init(int32_t destCapacity, UErrorCode &errorCode) {
  int32_t length=str.length();
  start=str.getBuffer(destCapacity);
  if(start==NULL__null) {
      // getBuffer() already did str.setToBogus()
      errorCode=U_MEMORY_ALLOCATION_ERROR;
      return FALSE0;
  }
  limit=start+length;
  remainingCapacity=str.getCapacity()-length;
  reorderStart=start;
  if(start==limit) {
      lastCC=0;
  } else {
      setIterator();
      lastCC=previousCC();
      // Set reorderStart after the last code point with cc<=1 if there is one.
      if(lastCC>1) {
          while(previousCC()>1) {}
      }
      reorderStart=codePointLimit;
  }
  return TRUE1;
205}

207UBool ReorderingBuffer::equals(const UChar *otherStart, const UChar *otherLimit) const {
  int32_t length=(int32_t)(limit-start);
  return
      length==(int32_t)(otherLimit-otherStart) &&
      0==u_memcmpu_memcmp_71(start, otherStart, length);
212}

214UBool ReorderingBuffer::equals(const uint8_t *otherStart, const uint8_t *otherLimit) const {
  U_ASSERT((otherLimit - otherStart) <= INT32_MAX)(void)0;  // ensured by caller
  int32_t length = (int32_t)(limit - start);
  int32_t otherLength = (int32_t)(otherLimit - otherStart);
  // For equal strings, UTF-8 is at least as long as UTF-16, and at most three times as long.
  if (otherLength < length || (otherLength / 3) > length) {
      return FALSE0;
  }
  // Compare valid strings from between normalization boundaries.
  // (Invalid sequences are normalization-inert.)
  for (int32_t i = 0, j = 0;;) {
      if (i >= length) {
          return j >= otherLength;
      } else if (j >= otherLength) {
          return FALSE0;
      }
      // Not at the end of either string yet.
      UChar32 c, other;
      U16_NEXT_UNSAFE(start, i, c)do { (c)=(start)[(i)++]; if((((c)&0xfffffc00)==0xd800)) {
 (c)=(((UChar32)((c))<<10UL)+(UChar32)((start)[(i)++])-
((0xd800<<10UL)+0xdc00-0x10000)); } } while (false);
      U8_NEXT_UNSAFE(otherStart, j, other)do { (other)=(uint8_t)(otherStart)[(j)++]; if(!(((other)&
0x80)==0)) { if((other)<0xe0) { (other)=(((other)&0x1f
)<<6)|((otherStart)[(j)++]&0x3f); } else if((other)
<0xf0) { (other)=(UChar)(((other)<<12)|(((otherStart
)[j]&0x3f)<<6)|((otherStart)[(j)+1]&0x3f)); (j)
+=2; } else { (other)=(((other)&7)<<18)|(((otherStart
)[j]&0x3f)<<12)|(((otherStart)[(j)+1]&0x3f)<<
6)|((otherStart)[(j)+2]&0x3f); (j)+=3; } } } while (false
);
      if (c != other) {
          return FALSE0;
      }
  }
238}

240UBool ReorderingBuffer::appendSupplementary(UChar32 c, uint8_t cc, UErrorCode &errorCode) {
  if(remainingCapacity<2 && !resize(2, errorCode)) {
      return FALSE0;
  }
  if(lastCC<=cc || cc==0) {
      limit[0]=U16_LEAD(c)(UChar)(((c)>>10)+0xd7c0);
      limit[1]=U16_TRAIL(c)(UChar)(((c)&0x3ff)|0xdc00);
      limit+=2;
      lastCC=cc;
      if(cc<=1) {
          reorderStart=limit;
      }
  } else {
      insert(c, cc);
  }
  remainingCapacity-=2;
  return TRUE1;
257}

259UBool ReorderingBuffer::append(const UChar *s, int32_t length, UBool isNFD,
                             uint8_t leadCC, uint8_t trailCC,
                             UErrorCode &errorCode) {
  if(length==0) {
      return TRUE1;
  }
  if(remainingCapacity<length && !resize(length, errorCode)) {
      return FALSE0;
  }
  remainingCapacity-=length;
  if(lastCC<=leadCC || leadCC==0) {
      if(trailCC<=1) {
          reorderStart=limit+length;
      } else if(leadCC<=1) {
          reorderStart=limit+1;  // Ok if not a code point boundary.
      }
      const UChar *sLimit=s+length;
      do { *limit++=*s++; } while(s!=sLimit);
      lastCC=trailCC;
  } else {
      int32_t i=0;
      UChar32 c;
      U16_NEXT(s, i, length, c)do { (c)=(s)[(i)++]; if((((c)&0xfffffc00)==0xd800)) { uint16_t
 __c2; if((i)!=(length) && (((__c2=(s)[(i)])&0xfffffc00
)==0xdc00)) { ++(i); (c)=(((UChar32)((c))<<10UL)+(UChar32
)(__c2)-((0xd800<<10UL)+0xdc00-0x10000)); } } } while (
false);
      insert(c, leadCC);  // insert first code point
      while(i<length) {
          U16_NEXT(s, i, length, c)do { (c)=(s)[(i)++]; if((((c)&0xfffffc00)==0xd800)) { uint16_t
 __c2; if((i)!=(length) && (((__c2=(s)[(i)])&0xfffffc00
)==0xdc00)) { ++(i); (c)=(((UChar32)((c))<<10UL)+(UChar32
)(__c2)-((0xd800<<10UL)+0xdc00-0x10000)); } } } while (
false);
          if(i<length) {
              if (isNFD) {
                  leadCC = Normalizer2Impl::getCCFromYesOrMaybe(impl.getRawNorm16(c));
              } else {
                  leadCC = impl.getCC(impl.getNorm16(c));
              }
          } else {
              leadCC=trailCC;
          }
          append(c, leadCC, errorCode);
      }
  }
  return TRUE1;
298}

300UBool ReorderingBuffer::appendZeroCC(UChar32 c, UErrorCode &errorCode) {
  int32_t cpLength=U16_LENGTH(c)((uint32_t)(c)<=0xffff ? 1 : 2);
  if(remainingCapacity<cpLength && !resize(cpLength, errorCode)) {
      return FALSE0;
  }
  remainingCapacity-=cpLength;
  if(cpLength==1) {
      *limit++=(UChar)c;
  } else {
      limit[0]=U16_LEAD(c)(UChar)(((c)>>10)+0xd7c0);
      limit[1]=U16_TRAIL(c)(UChar)(((c)&0x3ff)|0xdc00);
      limit+=2;
  }
  lastCC=0;
  reorderStart=limit;
  return TRUE1;
316}

318UBool ReorderingBuffer::appendZeroCC(const UChar *s, const UChar *sLimit, UErrorCode &errorCode) {
  if(s==sLimit) {
      return TRUE1;
  }
  int32_t length=(int32_t)(sLimit-s);
  if(remainingCapacity<length && !resize(length, errorCode)) {
      return FALSE0;
  }
  u_memcpyu_memcpy_71(limit, s, length);
  limit+=length;
  remainingCapacity-=length;
  lastCC=0;
  reorderStart=limit;
  return TRUE1;
332}

334void ReorderingBuffer::remove() {
  reorderStart=limit=start;
  remainingCapacity=str.getCapacity();
  lastCC=0;
338}

340void ReorderingBuffer::removeSuffix(int32_t suffixLength) {
  if(suffixLength<(limit-start)) {
      limit-=suffixLength;
      remainingCapacity+=suffixLength;
  } else {
      limit=start;
      remainingCapacity=str.getCapacity();
  }
  lastCC=0;
  reorderStart=limit;
350}

352UBool ReorderingBuffer::resize(int32_t appendLength, UErrorCode &errorCode) {
  int32_t reorderStartIndex=(int32_t)(reorderStart-start);
  int32_t length=(int32_t)(limit-start);
  str.releaseBuffer(length);
  int32_t newCapacity=length+appendLength;
  int32_t doubleCapacity=2*str.getCapacity();
  if(newCapacity<doubleCapacity) {
      newCapacity=doubleCapacity;
  }
  if(newCapacity<256) {
      newCapacity=256;
  }
  start=str.getBuffer(newCapacity);
  if(start==NULL__null) {
      // getBuffer() already did str.setToBogus()
      errorCode=U_MEMORY_ALLOCATION_ERROR;
      return FALSE0;
  }
  reorderStart=start+reorderStartIndex;
  limit=start+length;
  remainingCapacity=str.getCapacity()-length;
  return TRUE1;
374}

376void ReorderingBuffer::skipPrevious() {
  codePointLimit=codePointStart;
  UChar c=*--codePointStart;
  if(U16_IS_TRAIL(c)(((c)&0xfffffc00)==0xdc00) && start<codePointStart && U16_IS_LEAD(*(codePointStart-1))(((*(codePointStart-1))&0xfffffc00)==0xd800)) {
      --codePointStart;
  }
382}

384uint8_t ReorderingBuffer::previousCC() {
  codePointLimit=codePointStart;
  if(reorderStart>=codePointStart) {
      return 0;
  }
  UChar32 c=*--codePointStart;
  UChar c2;
  if(U16_IS_TRAIL(c)(((c)&0xfffffc00)==0xdc00) && start<codePointStart && U16_IS_LEAD(c2=*(codePointStart-1))(((c2=*(codePointStart-1))&0xfffffc00)==0xd800)) {
      --codePointStart;
      c=U16_GET_SUPPLEMENTARY(c2, c)(((UChar32)(c2)<<10UL)+(UChar32)(c)-((0xd800<<10UL
)+0xdc00-0x10000));
  }
  return impl.getCCFromYesOrMaybeCP(c);
396}

398// Inserts c somewhere before the last character.
399// Requires 0<cc<lastCC which implies reorderStart<limit.
400void ReorderingBuffer::insert(UChar32 c, uint8_t cc) {
  for(setIterator(), skipPrevious(); previousCC()>cc;) {}
  // insert c at codePointLimit, after the character with prevCC<=cc
  UChar *q=limit;
  UChar *r=limit+=U16_LENGTH(c)((uint32_t)(c)<=0xffff ? 1 : 2);
  do {
      *--r=*--q;
  } while(codePointLimit!=q);
  writeCodePoint(q, c);
  if(cc<=1) {
      reorderStart=r;
  }
412}

414// Normalizer2Impl --------------------------------------------------------- ***

416struct CanonIterData : public UMemory {
  CanonIterData(UErrorCode &errorCode);
  ~CanonIterData();
  void addToStartSet(UChar32 origin, UChar32 decompLead, UErrorCode &errorCode);
  UMutableCPTrie *mutableTrie;
  UCPTrie *trie;
  UVector canonStartSets;  // contains UnicodeSet *
423};

425Normalizer2Impl::~Normalizer2Impl() {
  delete fCanonIterData;
427}

429void
430Normalizer2Impl::init(const int32_t *inIndexes, const UCPTrie *inTrie,
                    const uint16_t *inExtraData, const uint8_t *inSmallFCD) {
  minDecompNoCP = static_cast<UChar>(inIndexes[IX_MIN_DECOMP_NO_CP]);
  minCompNoMaybeCP = static_cast<UChar>(inIndexes[IX_MIN_COMP_NO_MAYBE_CP]);
  minLcccCP = static_cast<UChar>(inIndexes[IX_MIN_LCCC_CP]);

  minYesNo = static_cast<uint16_t>(inIndexes[IX_MIN_YES_NO]);
  minYesNoMappingsOnly = static_cast<uint16_t>(inIndexes[IX_MIN_YES_NO_MAPPINGS_ONLY]);
  minNoNo = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO]);
  minNoNoCompBoundaryBefore = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO_COMP_BOUNDARY_BEFORE]);
  minNoNoCompNoMaybeCC = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO_COMP_NO_MAYBE_CC]);
  minNoNoEmpty = static_cast<uint16_t>(inIndexes[IX_MIN_NO_NO_EMPTY]);
  limitNoNo = static_cast<uint16_t>(inIndexes[IX_LIMIT_NO_NO]);
  minMaybeYes = static_cast<uint16_t>(inIndexes[IX_MIN_MAYBE_YES]);
  U_ASSERT((minMaybeYes & 7) == 0)(void)0;  // 8-aligned for noNoDelta bit fields
  centerNoNoDelta = (minMaybeYes >> DELTA_SHIFT) - MAX_DELTA - 1;

  normTrie=inTrie;

  maybeYesCompositions=inExtraData;
  extraData=maybeYesCompositions+((MIN_NORMAL_MAYBE_YES-minMaybeYes)>>OFFSET_SHIFT);

  smallFCD=inSmallFCD;
453}

455U_CDECL_BEGINextern "C" {

457static uint32_t U_CALLCONV
458segmentStarterMapper(const void * /*context*/, uint32_t value) {
  return value&CANON_NOT_SEGMENT_STARTER0x80000000;
460}

462U_CDECL_END}

464void
465Normalizer2Impl::addLcccChars(UnicodeSet &set) const {
  UChar32 start = 0, end;
  uint32_t norm16;
  while ((end = ucptrie_getRangeucptrie_getRange_71(normTrie, start, UCPMAP_RANGE_FIXED_LEAD_SURROGATES, INERT,
                                 nullptr, nullptr, &norm16)) >= 0) {
      if (norm16 > Normalizer2Impl::MIN_NORMAL_MAYBE_YES &&
              norm16 != Normalizer2Impl::JAMO_VT) {
          set.add(start, end);
      } else if (minNoNoCompNoMaybeCC <= norm16 && norm16 < limitNoNo) {
          uint16_t fcd16 = getFCD16(start);
          if (fcd16 > 0xff) { set.add(start, end); }
      }
      start = end + 1;
  }
479}

481void
482Normalizer2Impl::addPropertyStarts(const USetAdder *sa, UErrorCode & /*errorCode*/) const {
  // Add the start code point of each same-value range of the trie.
  UChar32 start = 0, end;
  uint32_t value;
  while ((end = ucptrie_getRangeucptrie_getRange_71(normTrie, start, UCPMAP_RANGE_FIXED_LEAD_SURROGATES, INERT,
                                 nullptr, nullptr, &value)) >= 0) {
      sa->add(sa->set, start);
      if (start != end && isAlgorithmicNoNo((uint16_t)value) &&
              (value & Normalizer2Impl::DELTA_TCCC_MASK) > Normalizer2Impl::DELTA_TCCC_1) {
          // Range of code points with same-norm16-value algorithmic decompositions.
          // They might have different non-zero FCD16 values.
          uint16_t prevFCD16 = getFCD16(start);
          while (++start <= end) {
              uint16_t fcd16 = getFCD16(start);
              if (fcd16 != prevFCD16) {
                  sa->add(sa->set, start);
                  prevFCD16 = fcd16;
              }
          }
      }
      start = end + 1;
  }

  /* add Hangul LV syllables and LV+1 because of skippables */
  for(UChar c=Hangul::HANGUL_BASE; c<Hangul::HANGUL_LIMIT; c+=Hangul::JAMO_T_COUNT) {
      sa->add(sa->set, c);
      sa->add(sa->set, c+1);
  }
  sa->add(sa->set, Hangul::HANGUL_LIMIT); /* add Hangul+1 to continue with other properties */
511}

513void
514Normalizer2Impl::addCanonIterPropertyStarts(const USetAdder *sa, UErrorCode &errorCode) const {
  // Add the start code point of each same-value range of the canonical iterator data trie.
  if (!ensureCanonIterData(errorCode)) { return; }
  // Currently only used for the SEGMENT_STARTER property.
  UChar32 start = 0, end;
  uint32_t value;
  while ((end = ucptrie_getRangeucptrie_getRange_71(fCanonIterData->trie, start, UCPMAP_RANGE_NORMAL, 0,
                                 segmentStarterMapper, nullptr, &value)) >= 0) {
      sa->add(sa->set, start);
      start = end + 1;
  }
525}

527const UChar *
528Normalizer2Impl::copyLowPrefixFromNulTerminated(const UChar *src,
                                              UChar32 minNeedDataCP,
                                              ReorderingBuffer *buffer,
                                              UErrorCode &errorCode) const {
  // Make some effort to support NUL-terminated strings reasonably.
  // Take the part of the fast quick check loop that does not look up
  // data and check the first part of the string.
  // After this prefix, determine the string length to simplify the rest
  // of the code.
  const UChar *prevSrc=src;
  UChar c;
  while((c=*src++)<minNeedDataCP && c!=0) {}
6
←
Null pointer value stored to 'src'→
7
←
Dereference of null pointer
  // Back out the last character for full processing.
  // Copy this prefix.
  if(--src!=prevSrc) {
      if(buffer!=NULL__null) {
          buffer->appendZeroCC(prevSrc, src, errorCode);
      }
  }
  return src;
548}

550UnicodeString &
551Normalizer2Impl::decompose(const UnicodeString &src, UnicodeString &dest,
                         UErrorCode &errorCode) const {
  if(U_FAILURE(errorCode)) {
      dest.setToBogus();
      return dest;
  }
  const UChar *sArray=src.getBuffer();
  if(&dest==&src || sArray==NULL__null) {
      errorCode=U_ILLEGAL_ARGUMENT_ERROR;
      dest.setToBogus();
      return dest;
  }
  decompose(sArray, sArray+src.length(), dest, src.length(), errorCode);
  return dest;
565}

567void
568Normalizer2Impl::decompose(const UChar *src, const UChar *limit,
                         UnicodeString &dest,
                         int32_t destLengthEstimate,
                         UErrorCode &errorCode) const {
  if(destLengthEstimate<0 && limit!=NULL__null) {
      destLengthEstimate=(int32_t)(limit-src);
  }
  dest.remove();
  ReorderingBuffer buffer(*this, dest);
  if(buffer.init(destLengthEstimate, errorCode)) {
      decompose(src, limit, &buffer, errorCode);
  }
580}

582// Dual functionality:
583// buffer!=NULL: normalize
584// buffer==NULL: isNormalized/spanQuickCheckYes
585const UChar *
586Normalizer2Impl::decompose(const UChar *src, const UChar *limit,
                         ReorderingBuffer *buffer,
                         UErrorCode &errorCode) const {
  UChar32 minNoCP=minDecompNoCP;
  if(limit==NULL__null) {
      src=copyLowPrefixFromNulTerminated(src, minNoCP, buffer, errorCode);
      if(U_FAILURE(errorCode)) {
          return src;
      }
      limit=u_strchru_strchr_71(src, 0);
  }

  const UChar *prevSrc;
  UChar32 c=0;
  uint16_t norm16=0;

  // only for quick check
  const UChar *prevBoundary=src;
  uint8_t prevCC=0;

  for(;;) {
      // count code units below the minimum or with irrelevant data for the quick check
      for(prevSrc=src; src!=limit;) {
          if( (c=*src)<minNoCP ||
              isMostDecompYesAndZeroCC(norm16=UCPTRIE_FAST_BMP_GET(normTrie, UCPTRIE_16, c)((normTrie)->data.ptr16[((int32_t)(normTrie)->index[(c)
 >> UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK
))]))
          ) {
              ++src;
          } else if(!U16_IS_LEAD(c)(((c)&0xfffffc00)==0xd800)) {
              break;
          } else {
              UChar c2;
              if((src+1)!=limit && U16_IS_TRAIL(c2=src[1])(((c2=src[1])&0xfffffc00)==0xdc00)) {
                  c=U16_GET_SUPPLEMENTARY(c, c2)(((UChar32)(c)<<10UL)+(UChar32)(c2)-((0xd800<<10UL
)+0xdc00-0x10000));
                  norm16=UCPTRIE_FAST_SUPP_GET(normTrie, UCPTRIE_16, c)((normTrie)->data.ptr16[((c) >= (normTrie)->highStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c))]);
                  if(isMostDecompYesAndZeroCC(norm16)) {
                      src+=2;
                  } else {
                      break;
                  }
              } else {
                  ++src;  // unpaired lead surrogate: inert
              }
          }
      }
      // copy these code units all at once
      if(src!=prevSrc) {
          if(buffer!=NULL__null) {
              if(!buffer->appendZeroCC(prevSrc, src, errorCode)) {
                  break;
              }
          } else {
              prevCC=0;
              prevBoundary=src;
          }
      }
      if(src==limit) {
          break;
      }

      // Check one above-minimum, relevant code point.
      src+=U16_LENGTH(c)((uint32_t)(c)<=0xffff ? 1 : 2);
      if(buffer!=NULL__null) {
          if(!decompose(c, norm16, *buffer, errorCode)) {
              break;
          }
      } else {
          if(isDecompYes(norm16)) {
              uint8_t cc=getCCFromYesOrMaybe(norm16);
              if(prevCC<=cc || cc==0) {
                  prevCC=cc;
                  if(cc<=1) {
                      prevBoundary=src;
                  }
                  continue;
              }
          }
          return prevBoundary;  // "no" or cc out of order
      }
  }
  return src;
666}

668// Decompose a short piece of text which is likely to contain characters that
669// fail the quick check loop and/or where the quick check loop's overhead
670// is unlikely to be amortized.
671// Called by the compose() and makeFCD() implementations.
672const UChar *
673Normalizer2Impl::decomposeShort(const UChar *src, const UChar *limit,
                              UBool stopAtCompBoundary, UBool onlyContiguous,
                              ReorderingBuffer &buffer, UErrorCode &errorCode) const {
  if (U_FAILURE(errorCode)) {
      return nullptr;
  }
  while(src<limit) {
      if (stopAtCompBoundary && *src < minCompNoMaybeCP) {
          return src;
      }
      const UChar *prevSrc = src;
      UChar32 c;
      uint16_t norm16;
      UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, src, limit, c, norm16)do { (c) = *(src)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (src
) != (limit) && (((__c2 = *(src))&0xfffffc00)==0xdc00
)) { ++(src); (c) = (((UChar32)((c))<<10UL)+(UChar32)(__c2
)-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c) >=
 (normTrie)->highStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c)); } else { __index
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (norm16) = ((normTrie)->data.ptr16[__index]); } while
 (false);
      if (stopAtCompBoundary && norm16HasCompBoundaryBefore(norm16)) {
          return prevSrc;
      }
      if(!decompose(c, norm16, buffer, errorCode)) {
          return nullptr;
      }
      if (stopAtCompBoundary && norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
          return src;
      }
  }
  return src;
698}

700UBool Normalizer2Impl::decompose(UChar32 c, uint16_t norm16,
                               ReorderingBuffer &buffer,
                               UErrorCode &errorCode) const {
  // get the decomposition and the lead and trail cc's
  if (norm16 >= limitNoNo) {
      if (isMaybeOrNonZeroCC(norm16)) {
          return buffer.append(c, getCCFromYesOrMaybe(norm16), errorCode);
      }
      // Maps to an isCompYesAndZeroCC.
      c=mapAlgorithmic(c, norm16);
      norm16=getRawNorm16(c);
  }
  if (norm16 < minYesNo) {
      // c does not decompose
      return buffer.append(c, 0, errorCode);
  } else if(isHangulLV(norm16) || isHangulLVT(norm16)) {
      // Hangul syllable: decompose algorithmically
      UChar jamos[3];
      return buffer.appendZeroCC(jamos, jamos+Hangul::decompose(c, jamos), errorCode);
  }
  // c decomposes, get everything from the variable-length extra data
  const uint16_t *mapping=getMapping(norm16);
  uint16_t firstUnit=*mapping;
  int32_t length=firstUnit&MAPPING_LENGTH_MASK;
  uint8_t leadCC, trailCC;
  trailCC=(uint8_t)(firstUnit>>8);
  if(firstUnit&MAPPING_HAS_CCC_LCCC_WORD) {
      leadCC=(uint8_t)(*(mapping-1)>>8);
  } else {
      leadCC=0;
  }
  return buffer.append((const UChar *)mapping+1, length, TRUE1, leadCC, trailCC, errorCode);
732}

734// Dual functionality:
735// sink != nullptr: normalize
736// sink == nullptr: isNormalized/spanQuickCheckYes
737const uint8_t *
738Normalizer2Impl::decomposeUTF8(uint32_t options,
                             const uint8_t *src, const uint8_t *limit,
                             ByteSink *sink, Edits *edits, UErrorCode &errorCode) const {
  U_ASSERT(limit != nullptr)(void)0;
  UnicodeString s16;
  uint8_t minNoLead = leadByteForCP(minDecompNoCP);

  const uint8_t *prevBoundary = src;
  // only for quick check
  uint8_t prevCC = 0;

  for (;;) {
      // Fast path: Scan over a sequence of characters below the minimum "no" code point,
      // or with (decompYes && ccc==0) properties.
      const uint8_t *fastStart = src;
      const uint8_t *prevSrc;
      uint16_t norm16 = 0;

      for (;;) {
          if (src == limit) {
              if (prevBoundary != limit && sink != nullptr) {
                  ByteSinkUtil::appendUnchanged(prevBoundary, limit,
                                                *sink, options, edits, errorCode);
              }
              return src;
          }
          if (*src < minNoLead) {
              ++src;
          } else {
              prevSrc = src;
              UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16)do { int32_t __lead = (uint8_t)*(src)++; if (!(((__lead)&
0x80)==0)) { uint8_t __t1, __t2, __t3; if ((src) != (limit) &&
 (__lead >= 0xe0 ? __lead < 0xf0 ? "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
[__lead &= 0xf] & (1 << ((__t1 = *(src)) >>
 5)) && ++(src) != (limit) && (__t2 = *(src) -
 0x80) <= 0x3f && (__lead = ((int32_t)(normTrie)->
index[(__lead << 6) + (__t1 & 0x3f)]) + __t2, 1) : (
__lead -= 0xf0) <= 4 && "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
[(__t1 = *(src)) >> 4] & (1 << __lead) &&
 (__lead = (__lead << 6) | (__t1 & 0x3f), ++(src) !=
 (limit)) && (__t2 = *(src) - 0x80) <= 0x3f &&
 ++(src) != (limit) && (__t3 = *(src) - 0x80) <= 0x3f
 && (__lead = __lead >= (normTrie)->shifted12HighStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallU8Index_71((normTrie), __lead, __t2, __t3
), 1) : __lead >= 0xc2 && (__t1 = *(src) - 0x80) <=
 0x3f && (__lead = (int32_t)(normTrie)->index[__lead
 & 0x1f] + __t1, 1))) { ++(src); } else { __lead = (normTrie
)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (
norm16) = ((normTrie)->data.ptr16[__lead]); } while (false
);
              if (!isMostDecompYesAndZeroCC(norm16)) {
                  break;
              }
          }
      }
      // isMostDecompYesAndZeroCC(norm16) is false, that is, norm16>=minYesNo,
      // and the current character at [prevSrc..src[ is not a common case with cc=0
      // (MIN_NORMAL_MAYBE_YES or JAMO_VT).
      // It could still be a maybeYes with cc=0.
      if (prevSrc != fastStart) {
          // The fast path looped over yes/0 characters before the current one.
          if (sink != nullptr &&
                  !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                 *sink, options, edits, errorCode)) {
              break;
          }
          prevBoundary = prevSrc;
          prevCC = 0;
      }

      // Medium-fast path: Quick check.
      if (isMaybeOrNonZeroCC(norm16)) {
          // Does not decompose.
          uint8_t cc = getCCFromYesOrMaybe(norm16);
          if (prevCC <= cc || cc == 0) {
              prevCC = cc;
              if (cc <= 1) {
                  if (sink != nullptr &&
                          !ByteSinkUtil::appendUnchanged(prevBoundary, src,
                                                         *sink, options, edits, errorCode)) {
                      break;
                  }
                  prevBoundary = src;
              }
              continue;
          }
      }
      if (sink == nullptr) {
          return prevBoundary;  // quick check: "no" or cc out of order
      }

      // Slow path
      // Decompose up to and including the current character.
      if (prevBoundary != prevSrc && norm16HasDecompBoundaryBefore(norm16)) {
          if (!ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                             *sink, options, edits, errorCode)) {
              break;
          }
          prevBoundary = prevSrc;
      }
      ReorderingBuffer buffer(*this, s16, errorCode);
      if (U_FAILURE(errorCode)) {
          break;
      }
      decomposeShort(prevBoundary, src, STOP_AT_LIMIT, FALSE0 /* onlyContiguous */,
                     buffer, errorCode);
      // Decompose until the next boundary.
      if (buffer.getLastCC() > 1) {
          src = decomposeShort(src, limit, STOP_AT_DECOMP_BOUNDARY, FALSE0 /* onlyContiguous */,
                               buffer, errorCode);
      }
      if (U_FAILURE(errorCode)) {
          break;
      }
      if ((src - prevSrc) > INT32_MAX(2147483647)) {  // guard before buffer.equals()
          errorCode = U_INDEX_OUTOFBOUNDS_ERROR;
          break;
      }
      // We already know there was a change if the original character decomposed;
      // otherwise compare.
      if (isMaybeOrNonZeroCC(norm16) && buffer.equals(prevBoundary, src)) {
          if (!ByteSinkUtil::appendUnchanged(prevBoundary, src,
                                             *sink, options, edits, errorCode)) {
              break;
          }
      } else {
          if (!ByteSinkUtil::appendChange(prevBoundary, src, buffer.getStart(), buffer.length(),
                                          *sink, edits, errorCode)) {
              break;
          }
      }
      prevBoundary = src;
      prevCC = 0;
  }
  return src;
854}

856const uint8_t *
857Normalizer2Impl::decomposeShort(const uint8_t *src, const uint8_t *limit,
                              StopAt stopAt, UBool onlyContiguous,
                              ReorderingBuffer &buffer, UErrorCode &errorCode) const {
  if (U_FAILURE(errorCode)) {
      return nullptr;
  }
  while (src < limit) {
      const uint8_t *prevSrc = src;
      uint16_t norm16;
      UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16)do { int32_t __lead = (uint8_t)*(src)++; if (!(((__lead)&
0x80)==0)) { uint8_t __t1, __t2, __t3; if ((src) != (limit) &&
 (__lead >= 0xe0 ? __lead < 0xf0 ? "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
[__lead &= 0xf] & (1 << ((__t1 = *(src)) >>
 5)) && ++(src) != (limit) && (__t2 = *(src) -
 0x80) <= 0x3f && (__lead = ((int32_t)(normTrie)->
index[(__lead << 6) + (__t1 & 0x3f)]) + __t2, 1) : (
__lead -= 0xf0) <= 4 && "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
[(__t1 = *(src)) >> 4] & (1 << __lead) &&
 (__lead = (__lead << 6) | (__t1 & 0x3f), ++(src) !=
 (limit)) && (__t2 = *(src) - 0x80) <= 0x3f &&
 ++(src) != (limit) && (__t3 = *(src) - 0x80) <= 0x3f
 && (__lead = __lead >= (normTrie)->shifted12HighStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallU8Index_71((normTrie), __lead, __t2, __t3
), 1) : __lead >= 0xc2 && (__t1 = *(src) - 0x80) <=
 0x3f && (__lead = (int32_t)(normTrie)->index[__lead
 & 0x1f] + __t1, 1))) { ++(src); } else { __lead = (normTrie
)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (
norm16) = ((normTrie)->data.ptr16[__lead]); } while (false
);
      // Get the decomposition and the lead and trail cc's.
      UChar32 c = U_SENTINEL(-1);
      if (norm16 >= limitNoNo) {
          if (isMaybeOrNonZeroCC(norm16)) {
              // No comp boundaries around this character.
              uint8_t cc = getCCFromYesOrMaybe(norm16);
              if (cc == 0 && stopAt == STOP_AT_DECOMP_BOUNDARY) {
                  return prevSrc;
              }
              c = codePointFromValidUTF8(prevSrc, src);
              if (!buffer.append(c, cc, errorCode)) {
                  return nullptr;
              }
              if (stopAt == STOP_AT_DECOMP_BOUNDARY && buffer.getLastCC() <= 1) {
                  return src;
              }
              continue;
          }
          // Maps to an isCompYesAndZeroCC.
          if (stopAt != STOP_AT_LIMIT) {
              return prevSrc;
          }
          c = codePointFromValidUTF8(prevSrc, src);
          c = mapAlgorithmic(c, norm16);
          norm16 = getRawNorm16(c);
      } else if (stopAt != STOP_AT_LIMIT && norm16 < minNoNoCompNoMaybeCC) {
          return prevSrc;
      }
      // norm16!=INERT guarantees that [prevSrc, src[ is valid UTF-8.
      // We do not see invalid UTF-8 here because
      // its norm16==INERT is normalization-inert,
      // so it gets copied unchanged in the fast path,
      // and we stop the slow path where invalid UTF-8 begins.
      // c >= 0 is the result of an algorithmic mapping.
      U_ASSERT(c >= 0 || norm16 != INERT)(void)0;
      if (norm16 < minYesNo) {
          if (c < 0) {
              c = codePointFromValidUTF8(prevSrc, src);
          }
          // does not decompose
          if (!buffer.append(c, 0, errorCode)) {
              return nullptr;
          }
      } else if (isHangulLV(norm16) || isHangulLVT(norm16)) {
          // Hangul syllable: decompose algorithmically
          if (c < 0) {
              c = codePointFromValidUTF8(prevSrc, src);
          }
          char16_t jamos[3];
          if (!buffer.appendZeroCC(jamos, jamos+Hangul::decompose(c, jamos), errorCode)) {
              return nullptr;
          }
      } else {
          // The character decomposes, get everything from the variable-length extra data.
          const uint16_t *mapping = getMapping(norm16);
          uint16_t firstUnit = *mapping;
          int32_t length = firstUnit & MAPPING_LENGTH_MASK;
          uint8_t trailCC = (uint8_t)(firstUnit >> 8);
          uint8_t leadCC;
          if (firstUnit & MAPPING_HAS_CCC_LCCC_WORD) {
              leadCC = (uint8_t)(*(mapping-1) >> 8);
          } else {
              leadCC = 0;
          }
          if (leadCC == 0 && stopAt == STOP_AT_DECOMP_BOUNDARY) {
              return prevSrc;
          }
          if (!buffer.append((const char16_t *)mapping+1, length, TRUE1, leadCC, trailCC, errorCode)) {
              return nullptr;
          }
      }
      if ((stopAt == STOP_AT_COMP_BOUNDARY && norm16HasCompBoundaryAfter(norm16, onlyContiguous)) ||
              (stopAt == STOP_AT_DECOMP_BOUNDARY && buffer.getLastCC() <= 1)) {
          return src;
      }
  }
  return src;
944}

946const UChar *
947Normalizer2Impl::getDecomposition(UChar32 c, UChar buffer[4], int32_t &length) const {
  uint16_t norm16;
  if(c<minDecompNoCP || isMaybeOrNonZeroCC(norm16=getNorm16(c))) {
      // c does not decompose
      return nullptr;
  }
  const UChar *decomp = nullptr;
  if(isDecompNoAlgorithmic(norm16)) {
      // Maps to an isCompYesAndZeroCC.
      c=mapAlgorithmic(c, norm16);
      decomp=buffer;
      length=0;
      U16_APPEND_UNSAFE(buffer, length, c)do { if((uint32_t)(c)<=0xffff) { (buffer)[(length)++]=(uint16_t
)(c); } else { (buffer)[(length)++]=(uint16_t)(((c)>>10
)+0xd7c0); (buffer)[(length)++]=(uint16_t)(((c)&0x3ff)|0xdc00
); } } while (false);
      // The mapping might decompose further.
      norm16 = getRawNorm16(c);
  }
  if (norm16 < minYesNo) {
      return decomp;
  } else if(isHangulLV(norm16) || isHangulLVT(norm16)) {
      // Hangul syllable: decompose algorithmically
      length=Hangul::decompose(c, buffer);
      return buffer;
  }
  // c decomposes, get everything from the variable-length extra data
  const uint16_t *mapping=getMapping(norm16);
  length=*mapping&MAPPING_LENGTH_MASK;
  return (const UChar *)mapping+1;
974}

976// The capacity of the buffer must be 30=MAPPING_LENGTH_MASK-1
977// so that a raw mapping fits that consists of one unit ("rm0")
978// plus all but the first two code units of the normal mapping.
979// The maximum length of a normal mapping is 31=MAPPING_LENGTH_MASK.
980const UChar *
981Normalizer2Impl::getRawDecomposition(UChar32 c, UChar buffer[30], int32_t &length) const {
  uint16_t norm16;
  if(c<minDecompNoCP || isDecompYes(norm16=getNorm16(c))) {
      // c does not decompose
      return NULL__null;
  } else if(isHangulLV(norm16) || isHangulLVT(norm16)) {
      // Hangul syllable: decompose algorithmically
      Hangul::getRawDecomposition(c, buffer);
      length=2;
      return buffer;
  } else if(isDecompNoAlgorithmic(norm16)) {
      c=mapAlgorithmic(c, norm16);
      length=0;
      U16_APPEND_UNSAFE(buffer, length, c)do { if((uint32_t)(c)<=0xffff) { (buffer)[(length)++]=(uint16_t
)(c); } else { (buffer)[(length)++]=(uint16_t)(((c)>>10
)+0xd7c0); (buffer)[(length)++]=(uint16_t)(((c)&0x3ff)|0xdc00
); } } while (false);
      return buffer;
  }
  // c decomposes, get everything from the variable-length extra data
  const uint16_t *mapping=getMapping(norm16);
  uint16_t firstUnit=*mapping;
  int32_t mLength=firstUnit&MAPPING_LENGTH_MASK;  // length of normal mapping
  if(firstUnit&MAPPING_HAS_RAW_MAPPING) {
      // Read the raw mapping from before the firstUnit and before the optional ccc/lccc word.
      // Bit 7=MAPPING_HAS_CCC_LCCC_WORD
      const uint16_t *rawMapping=mapping-((firstUnit>>7)&1)-1;
      uint16_t rm0=*rawMapping;
      if(rm0<=MAPPING_LENGTH_MASK) {
          length=rm0;
          return (const UChar *)rawMapping-rm0;
      } else {
          // Copy the normal mapping and replace its first two code units with rm0.
          buffer[0]=(UChar)rm0;
          u_memcpyu_memcpy_71(buffer+1, (const UChar *)mapping+1+2, mLength-2);
          length=mLength-1;
          return buffer;
      }
  } else {
      length=mLength;
      return (const UChar *)mapping+1;
  }
1020}

1022void Normalizer2Impl::decomposeAndAppend(const UChar *src, const UChar *limit,
                                       UBool doDecompose,
                                       UnicodeString &safeMiddle,
                                       ReorderingBuffer &buffer,
                                       UErrorCode &errorCode) const {
  buffer.copyReorderableSuffixTo(safeMiddle);
  if(doDecompose) {
      decompose(src, limit, &buffer, errorCode);
      return;
  }
  // Just merge the strings at the boundary.
  bool isFirst = true;
  uint8_t firstCC = 0, prevCC = 0, cc;
  const UChar *p = src;
  while (p != limit) {
      const UChar *codePointStart = p;
      UChar32 c;
      uint16_t norm16;
      UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16)do { (c) = *(p)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (p
) != (limit) && (((__c2 = *(p))&0xfffffc00)==0xdc00
)) { ++(p); (c) = (((UChar32)((c))<<10UL)+(UChar32)(__c2
)-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c) >=
 (normTrie)->highStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c)); } else { __index
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (norm16) = ((normTrie)->data.ptr16[__index]); } while
 (false);
      if ((cc = getCC(norm16)) == 0) {
          p = codePointStart;
          break;
      }
      if (isFirst) {
          firstCC = cc;
          isFirst = false;
      }
      prevCC = cc;
  }
  if(limit==NULL__null) {  // appendZeroCC() needs limit!=NULL
      limit=u_strchru_strchr_71(p, 0);
  }

  if (buffer.append(src, (int32_t)(p - src), FALSE0, firstCC, prevCC, errorCode)) {
      buffer.appendZeroCC(p, limit, errorCode);
  }
1058}

1060UBool Normalizer2Impl::hasDecompBoundaryBefore(UChar32 c) const {
  return c < minLcccCP || (c <= 0xffff && !singleLeadMightHaveNonZeroFCD16(c)) ||
      norm16HasDecompBoundaryBefore(getNorm16(c));
1063}

1065UBool Normalizer2Impl::norm16HasDecompBoundaryBefore(uint16_t norm16) const {
  if (norm16 < minNoNoCompNoMaybeCC) {
      return TRUE1;
  }
  if (norm16 >= limitNoNo) {
      return norm16 <= MIN_NORMAL_MAYBE_YES || norm16 == JAMO_VT;
  }
  // c decomposes, get everything from the variable-length extra data
  const uint16_t *mapping=getMapping(norm16);
  uint16_t firstUnit=*mapping;
  // TRUE if leadCC==0 (hasFCDBoundaryBefore())
  return (firstUnit&MAPPING_HAS_CCC_LCCC_WORD)==0 || (*(mapping-1)&0xff00)==0;
1077}

1079UBool Normalizer2Impl::hasDecompBoundaryAfter(UChar32 c) const {
  if (c < minDecompNoCP) {
      return TRUE1;
  }
  if (c <= 0xffff && !singleLeadMightHaveNonZeroFCD16(c)) {
      return TRUE1;
  }
  return norm16HasDecompBoundaryAfter(getNorm16(c));
1087}

1089UBool Normalizer2Impl::norm16HasDecompBoundaryAfter(uint16_t norm16) const {
  if(norm16 <= minYesNo || isHangulLVT(norm16)) {
      return TRUE1;
  }
  if (norm16 >= limitNoNo) {
      if (isMaybeOrNonZeroCC(norm16)) {
          return norm16 <= MIN_NORMAL_MAYBE_YES || norm16 == JAMO_VT;
      }
      // Maps to an isCompYesAndZeroCC.
      return (norm16 & DELTA_TCCC_MASK) <= DELTA_TCCC_1;
  }
  // c decomposes, get everything from the variable-length extra data
  const uint16_t *mapping=getMapping(norm16);
  uint16_t firstUnit=*mapping;
  // decomp after-boundary: same as hasFCDBoundaryAfter(),
  // fcd16<=1 || trailCC==0
  if(firstUnit>0x1ff) {
      return FALSE0;  // trailCC>1
  }
  if(firstUnit<=0xff) {
      return TRUE1;  // trailCC==0
  }
  // if(trailCC==1) test leadCC==0, same as checking for before-boundary
  // TRUE if leadCC==0 (hasFCDBoundaryBefore())
  return (firstUnit&MAPPING_HAS_CCC_LCCC_WORD)==0 || (*(mapping-1)&0xff00)==0;
1114}

1116/*
* Finds the recomposition result for
* a forward-combining "lead" character,
* specified with a pointer to its compositions list,
* and a backward-combining "trail" character.
*
* If the lead and trail characters combine, then this function returns
* the following "compositeAndFwd" value:
* Bits 21..1  composite character
* Bit      0  set if the composite is a forward-combining starter
* otherwise it returns -1.
*
* The compositions list has (trail, compositeAndFwd) pair entries,
* encoded as either pairs or triples of 16-bit units.
* The last entry has the high bit of its first unit set.
*
* The list is sorted by ascending trail characters (there are no duplicates).
* A linear search is used.
*
* See normalizer2impl.h for a more detailed description
* of the compositions list format.
*/
1138int32_t Normalizer2Impl::combine(const uint16_t *list, UChar32 trail) {
  uint16_t key1, firstUnit;
  if(trail<COMP_1_TRAIL_LIMIT) {
      // trail character is 0..33FF
      // result entry may have 2 or 3 units
      key1=(uint16_t)(trail<<1);
      while(key1>(firstUnit=*list)) {
          list+=2+(firstUnit&COMP_1_TRIPLE);
      }
      if(key1==(firstUnit&COMP_1_TRAIL_MASK)) {
          if(firstUnit&COMP_1_TRIPLE) {
              return ((int32_t)list[1]<<16)|list[2];
          } else {
              return list[1];
          }
      }
  } else {
      // trail character is 3400..10FFFF
      // result entry has 3 units
      key1=(uint16_t)(COMP_1_TRAIL_LIMIT+
                      (((trail>>COMP_1_TRAIL_SHIFT))&
                        ~COMP_1_TRIPLE));
      uint16_t key2=(uint16_t)(trail<<COMP_2_TRAIL_SHIFT);
      uint16_t secondUnit;
      for(;;) {
          if(key1>(firstUnit=*list)) {
              list+=2+(firstUnit&COMP_1_TRIPLE);
          } else if(key1==(firstUnit&COMP_1_TRAIL_MASK)) {
              if(key2>(secondUnit=list[1])) {
                  if(firstUnit&COMP_1_LAST_TUPLE) {
                      break;
                  } else {
                      list+=3;
                  }
              } else if(key2==(secondUnit&COMP_2_TRAIL_MASK)) {
                  return ((int32_t)(secondUnit&~COMP_2_TRAIL_MASK)<<16)|list[2];
              } else {
                  break;
              }
          } else {
              break;
          }
      }
  }
  return -1;
1183}

1185/**
* @param list some character's compositions list
* @param set recursively receives the composites from these compositions
*/
1189void Normalizer2Impl::addComposites(const uint16_t *list, UnicodeSet &set) const {
  uint16_t firstUnit;
  int32_t compositeAndFwd;
  do {
      firstUnit=*list;
      if((firstUnit&COMP_1_TRIPLE)==0) {
          compositeAndFwd=list[1];
          list+=2;
      } else {
          compositeAndFwd=(((int32_t)list[1]&~COMP_2_TRAIL_MASK)<<16)|list[2];
          list+=3;
      }
      UChar32 composite=compositeAndFwd>>1;
      if((compositeAndFwd&1)!=0) {
          addComposites(getCompositionsListForComposite(getRawNorm16(composite)), set);
      }
      set.add(composite);
  } while((firstUnit&COMP_1_LAST_TUPLE)==0);
1207}

1209/*
* Recomposes the buffer text starting at recomposeStartIndex
* (which is in NFD - decomposed and canonically ordered),
* and truncates the buffer contents.
*
* Note that recomposition never lengthens the text:
* Any character consists of either one or two code units;
* a composition may contain at most one more code unit than the original starter,
* while the combining mark that is removed has at least one code unit.
*/
1219void Normalizer2Impl::recompose(ReorderingBuffer &buffer, int32_t recomposeStartIndex,
                              UBool onlyContiguous) const {
  UChar *p=buffer.getStart()+recomposeStartIndex;
  UChar *limit=buffer.getLimit();
  if(p==limit) {
      return;
  }

  UChar *starter, *pRemove, *q, *r;
  const uint16_t *compositionsList;
  UChar32 c, compositeAndFwd;
  uint16_t norm16;
  uint8_t cc, prevCC;
  UBool starterIsSupplementary;

  // Some of the following variables are not used until we have a forward-combining starter
  // and are only initialized now to avoid compiler warnings.
  compositionsList=NULL__null;  // used as indicator for whether we have a forward-combining starter
  starter=NULL__null;
  starterIsSupplementary=FALSE0;
  prevCC=0;

  for(;;) {
      UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16)do { (c) = *(p)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (p
) != (limit) && (((__c2 = *(p))&0xfffffc00)==0xdc00
)) { ++(p); (c) = (((UChar32)((c))<<10UL)+(UChar32)(__c2
)-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c) >=
 (normTrie)->highStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c)); } else { __index
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (norm16) = ((normTrie)->data.ptr16[__index]); } while
 (false);
      cc=getCCFromYesOrMaybe(norm16);
      if( // this character combines backward and
          isMaybe(norm16) &&
          // we have seen a starter that combines forward and
          compositionsList!=NULL__null &&
          // the backward-combining character is not blocked
          (prevCC<cc || prevCC==0)
      ) {
          if(isJamoVT(norm16)) {
              // c is a Jamo V/T, see if we can compose it with the previous character.
              if(c<Hangul::JAMO_T_BASE) {
                  // c is a Jamo Vowel, compose with previous Jamo L and following Jamo T.
                  UChar prev=(UChar)(*starter-Hangul::JAMO_L_BASE);
                  if(prev<Hangul::JAMO_L_COUNT) {
                      pRemove=p-1;
                      UChar syllable=(UChar)
                          (Hangul::HANGUL_BASE+
                           (prev*Hangul::JAMO_V_COUNT+(c-Hangul::JAMO_V_BASE))*
                           Hangul::JAMO_T_COUNT);
                      UChar t;
                      if(p!=limit && (t=(UChar)(*p-Hangul::JAMO_T_BASE))<Hangul::JAMO_T_COUNT) {
                          ++p;
                          syllable+=t;  // The next character was a Jamo T.
                      }
                      *starter=syllable;
                      // remove the Jamo V/T
                      q=pRemove;
                      r=p;
                      while(r<limit) {
                          *q++=*r++;
                      }
                      limit=q;
                      p=pRemove;
                  }
              }
              /*
               * No "else" for Jamo T:
               * Since the input is in NFD, there are no Hangul LV syllables that
               * a Jamo T could combine with.
               * All Jamo Ts are combined above when handling Jamo Vs.
               */
              if(p==limit) {
                  break;
              }
              compositionsList=NULL__null;
              continue;
          } else if((compositeAndFwd=combine(compositionsList, c))>=0) {
              // The starter and the combining mark (c) do combine.
              UChar32 composite=compositeAndFwd>>1;

              // Replace the starter with the composite, remove the combining mark.
              pRemove=p-U16_LENGTH(c)((uint32_t)(c)<=0xffff ? 1 : 2);  // pRemove & p: start & limit of the combining mark
              if(starterIsSupplementary) {
                  if(U_IS_SUPPLEMENTARY(composite)((uint32_t)((composite)-0x10000)<=0xfffff)) {
                      // both are supplementary
                      starter[0]=U16_LEAD(composite)(UChar)(((composite)>>10)+0xd7c0);
                      starter[1]=U16_TRAIL(composite)(UChar)(((composite)&0x3ff)|0xdc00);
                  } else {
                      *starter=(UChar)composite;
                      // The composite is shorter than the starter,
                      // move the intermediate characters forward one.
                      starterIsSupplementary=FALSE0;
                      q=starter+1;
                      r=q+1;
                      while(r<pRemove) {
                          *q++=*r++;
                      }
                      --pRemove;
                  }
              } else if(U_IS_SUPPLEMENTARY(composite)((uint32_t)((composite)-0x10000)<=0xfffff)) {
                  // The composite is longer than the starter,
                  // move the intermediate characters back one.
                  starterIsSupplementary=TRUE1;
                  ++starter;  // temporarily increment for the loop boundary
                  q=pRemove;
                  r=++pRemove;
                  while(starter<q) {
                      *--r=*--q;
                  }
                  *starter=U16_TRAIL(composite)(UChar)(((composite)&0x3ff)|0xdc00);
                  *--starter=U16_LEAD(composite)(UChar)(((composite)>>10)+0xd7c0);  // undo the temporary increment
              } else {
                  // both are on the BMP
                  *starter=(UChar)composite;
              }

              /* remove the combining mark by moving the following text over it */
              if(pRemove<p) {
                  q=pRemove;
                  r=p;
                  while(r<limit) {
                      *q++=*r++;
                  }
                  limit=q;
                  p=pRemove;
              }
              // Keep prevCC because we removed the combining mark.

              if(p==limit) {
                  break;
              }
              // Is the composite a starter that combines forward?
              if(compositeAndFwd&1) {
                  compositionsList=
                      getCompositionsListForComposite(getRawNorm16(composite));
              } else {
                  compositionsList=NULL__null;
              }

              // We combined; continue with looking for compositions.
              continue;
          }
      }

      // no combination this time
      prevCC=cc;
      if(p==limit) {
          break;
      }

      // If c did not combine, then check if it is a starter.
      if(cc==0) {
          // Found a new starter.
          if((compositionsList=getCompositionsListForDecompYes(norm16))!=NULL__null) {
              // It may combine with something, prepare for it.
              if(U_IS_BMP(c)((uint32_t)(c)<=0xffff)) {
                  starterIsSupplementary=FALSE0;
                  starter=p-1;
              } else {
                  starterIsSupplementary=TRUE1;
                  starter=p-2;
              }
          }
      } else if(onlyContiguous) {
          // FCC: no discontiguous compositions; any intervening character blocks.
          compositionsList=NULL__null;
      }
  }
  buffer.setReorderingLimit(limit);
1382}

1384UChar32
1385Normalizer2Impl::composePair(UChar32 a, UChar32 b) const {
  uint16_t norm16=getNorm16(a);  // maps an out-of-range 'a' to inert norm16
  const uint16_t *list;
  if(isInert(norm16)) {
      return U_SENTINEL(-1);
  } else if(norm16<minYesNoMappingsOnly) {
      // a combines forward.
      if(isJamoL(norm16)) {
          b-=Hangul::JAMO_V_BASE;
          if(0<=b && b<Hangul::JAMO_V_COUNT) {
              return
                  (Hangul::HANGUL_BASE+
                   ((a-Hangul::JAMO_L_BASE)*Hangul::JAMO_V_COUNT+b)*
                   Hangul::JAMO_T_COUNT);
          } else {
              return U_SENTINEL(-1);
          }
      } else if(isHangulLV(norm16)) {
          b-=Hangul::JAMO_T_BASE;
          if(0<b && b<Hangul::JAMO_T_COUNT) {  // not b==0!
              return a+b;
          } else {
              return U_SENTINEL(-1);
          }
      } else {
          // 'a' has a compositions list in extraData
          list=getMapping(norm16);
          if(norm16>minYesNo) {  // composite 'a' has both mapping & compositions list
              list+=  // mapping pointer
                  1+  // +1 to skip the first unit with the mapping length
                  (*list&MAPPING_LENGTH_MASK);  // + mapping length
          }
      }
  } else if(norm16<minMaybeYes || MIN_NORMAL_MAYBE_YES<=norm16) {
      return U_SENTINEL(-1);
  } else {
      list=getCompositionsListForMaybe(norm16);
  }
  if(b<0 || 0x10ffff<b) {  // combine(list, b) requires a valid code point b
      return U_SENTINEL(-1);
  }
1426#if U_SIGNED_RIGHT_SHIFT_IS_ARITHMETIC1
  return combine(list, b)>>1;
1428#else
  int32_t compositeAndFwd=combine(list, b);
  return compositeAndFwd>=0 ? compositeAndFwd>>1 : U_SENTINEL(-1);
1431#endif
1432}

1434// Very similar to composeQuickCheck(): Make the same changes in both places if relevant.
1435// doCompose: normalize
1436// !doCompose: isNormalized (buffer must be empty and initialized)
1437UBool
1438Normalizer2Impl::compose(const UChar *src, const UChar *limit,
                       UBool onlyContiguous,
                       UBool doCompose,
                       ReorderingBuffer &buffer,
                       UErrorCode &errorCode) const {
  const UChar *prevBoundary=src;
  UChar32 minNoMaybeCP=minCompNoMaybeCP;
  if(limit==NULL__null) {
      src=copyLowPrefixFromNulTerminated(src, minNoMaybeCP,
                                         doCompose ? &buffer : NULL__null,
                                         errorCode);
      if(U_FAILURE(errorCode)) {
          return FALSE0;
      }
      limit=u_strchru_strchr_71(src, 0);
      if (prevBoundary != src) {
          if (hasCompBoundaryAfter(*(src-1), onlyContiguous)) {
              prevBoundary = src;
          } else {
              buffer.removeSuffix(1);
              prevBoundary = --src;
          }
      }
  }

  for (;;) {
      // Fast path: Scan over a sequence of characters below the minimum "no or maybe" code point,
      // or with (compYes && ccc==0) properties.
      const UChar *prevSrc;
      UChar32 c = 0;
      uint16_t norm16 = 0;
      for (;;) {
          if (src == limit) {
              if (prevBoundary != limit && doCompose) {
                  buffer.appendZeroCC(prevBoundary, limit, errorCode);
              }
              return TRUE1;
          }
          if( (c=*src)<minNoMaybeCP ||
              isCompYesAndZeroCC(norm16=UCPTRIE_FAST_BMP_GET(normTrie, UCPTRIE_16, c)((normTrie)->data.ptr16[((int32_t)(normTrie)->index[(c)
 >> UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK
))]))
          ) {
              ++src;
          } else {
              prevSrc = src++;
              if(!U16_IS_LEAD(c)(((c)&0xfffffc00)==0xd800)) {
                  break;
              } else {
                  UChar c2;
                  if(src!=limit && U16_IS_TRAIL(c2=*src)(((c2=*src)&0xfffffc00)==0xdc00)) {
                      ++src;
                      c=U16_GET_SUPPLEMENTARY(c, c2)(((UChar32)(c)<<10UL)+(UChar32)(c2)-((0xd800<<10UL
)+0xdc00-0x10000));
                      norm16=UCPTRIE_FAST_SUPP_GET(normTrie, UCPTRIE_16, c)((normTrie)->data.ptr16[((c) >= (normTrie)->highStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c))]);
                      if(!isCompYesAndZeroCC(norm16)) {
                          break;
                      }
                  }
              }
          }
      }
      // isCompYesAndZeroCC(norm16) is false, that is, norm16>=minNoNo.
      // The current character is either a "noNo" (has a mapping)
      // or a "maybeYes" (combines backward)
      // or a "yesYes" with ccc!=0.
      // It is not a Hangul syllable or Jamo L because those have "yes" properties.

      // Medium-fast path: Handle cases that do not require full decomposition and recomposition.
      if (!isMaybeOrNonZeroCC(norm16)) {  // minNoNo <= norm16 < minMaybeYes
          if (!doCompose) {
              return FALSE0;
          }
          // Fast path for mapping a character that is immediately surrounded by boundaries.
          // In this case, we need not decompose around the current character.
          if (isDecompNoAlgorithmic(norm16)) {
              // Maps to a single isCompYesAndZeroCC character
              // which also implies hasCompBoundaryBefore.
              if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
                      hasCompBoundaryBefore(src, limit)) {
                  if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
                      break;
                  }
                  if(!buffer.append(mapAlgorithmic(c, norm16), 0, errorCode)) {
                      break;
                  }
                  prevBoundary = src;
                  continue;
              }
          } else if (norm16 < minNoNoCompBoundaryBefore) {
              // The mapping is comp-normalized which also implies hasCompBoundaryBefore.
              if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
                      hasCompBoundaryBefore(src, limit)) {
                  if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
                      break;
                  }
                  const UChar *mapping = reinterpret_cast<const UChar *>(getMapping(norm16));
                  int32_t length = *mapping++ & MAPPING_LENGTH_MASK;
                  if(!buffer.appendZeroCC(mapping, mapping + length, errorCode)) {
                      break;
                  }
                  prevBoundary = src;
                  continue;
              }
          } else if (norm16 >= minNoNoEmpty) {
              // The current character maps to nothing.
              // Simply omit it from the output if there is a boundary before _or_ after it.
              // The character itself implies no boundaries.
              if (hasCompBoundaryBefore(src, limit) ||
                      hasCompBoundaryAfter(prevBoundary, prevSrc, onlyContiguous)) {
                  if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
                      break;
                  }
                  prevBoundary = src;
                  continue;
              }
          }
          // Other "noNo" type, or need to examine more text around this character:
          // Fall through to the slow path.
      } else if (isJamoVT(norm16) && prevBoundary != prevSrc) {
          UChar prev=*(prevSrc-1);
          if(c<Hangul::JAMO_T_BASE) {
              // The current character is a Jamo Vowel,
              // compose with previous Jamo L and following Jamo T.
              UChar l = (UChar)(prev-Hangul::JAMO_L_BASE);
              if(l<Hangul::JAMO_L_COUNT) {
                  if (!doCompose) {
                      return FALSE0;
                  }
                  int32_t t;
                  if (src != limit &&
                          0 < (t = ((int32_t)*src - Hangul::JAMO_T_BASE)) &&
                          t < Hangul::JAMO_T_COUNT) {
                      // The next character is a Jamo T.
                      ++src;
                  } else if (hasCompBoundaryBefore(src, limit)) {
                      // No Jamo T follows, not even via decomposition.
                      t = 0;
                  } else {
                      t = -1;
                  }
                  if (t >= 0) {
                      UChar32 syllable = Hangul::HANGUL_BASE +
                          (l*Hangul::JAMO_V_COUNT + (c-Hangul::JAMO_V_BASE)) *
                          Hangul::JAMO_T_COUNT + t;
                      --prevSrc;  // Replace the Jamo L as well.
                      if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
                          break;
                      }
                      if(!buffer.appendBMP((UChar)syllable, 0, errorCode)) {
                          break;
                      }
                      prevBoundary = src;
                      continue;
                  }
                  // If we see L+V+x where x!=T then we drop to the slow path,
                  // decompose and recompose.
                  // This is to deal with NFKC finding normal L and V but a
                  // compatibility variant of a T.
                  // We need to either fully compose that combination here
                  // (which would complicate the code and may not work with strange custom data)
                  // or use the slow path.
              }
          } else if (Hangul::isHangulLV(prev)) {
              // The current character is a Jamo Trailing consonant,
              // compose with previous Hangul LV that does not contain a Jamo T.
              if (!doCompose) {
                  return FALSE0;
              }
              UChar32 syllable = prev + c - Hangul::JAMO_T_BASE;
              --prevSrc;  // Replace the Hangul LV as well.
              if (prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
                  break;
              }
              if(!buffer.appendBMP((UChar)syllable, 0, errorCode)) {
                  break;
              }
              prevBoundary = src;
              continue;
          }
          // No matching context, or may need to decompose surrounding text first:
          // Fall through to the slow path.
      } else if (norm16 > JAMO_VT) {  // norm16 >= MIN_YES_YES_WITH_CC
          // One or more combining marks that do not combine-back:
          // Check for canonical order, copy unchanged if ok and
          // if followed by a character with a boundary-before.
          uint8_t cc = getCCFromNormalYesOrMaybe(norm16);  // cc!=0
          if (onlyContiguous /* FCC */ && getPreviousTrailCC(prevBoundary, prevSrc) > cc) {
              // Fails FCD test, need to decompose and contiguously recompose.
              if (!doCompose) {
                  return FALSE0;
              }
          } else {
              // If !onlyContiguous (not FCC), then we ignore the tccc of
              // the previous character which passed the quick check "yes && ccc==0" test.
              const UChar *nextSrc;
              uint16_t n16;
              for (;;) {
                  if (src == limit) {
                      if (doCompose) {
                          buffer.appendZeroCC(prevBoundary, limit, errorCode);
                      }
                      return TRUE1;
                  }
                  uint8_t prevCC = cc;
                  nextSrc = src;
                  UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, nextSrc, limit, c, n16)do { (c) = *(nextSrc)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (nextSrc
) != (limit) && (((__c2 = *(nextSrc))&0xfffffc00)
==0xdc00)) { ++(nextSrc); (c) = (((UChar32)((c))<<10UL)
+(UChar32)(__c2)-((0xd800<<10UL)+0xdc00-0x10000)); __index
 = ((c) >= (normTrie)->highStart ? (normTrie)->dataLength
 - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (n16) = ((normTrie)
->data.ptr16[__index]); } while (false);
                  if (n16 >= MIN_YES_YES_WITH_CC) {
                      cc = getCCFromNormalYesOrMaybe(n16);
                      if (prevCC > cc) {
                          if (!doCompose) {
                              return FALSE0;
                          }
                          break;
                      }
                  } else {
                      break;
                  }
                  src = nextSrc;
              }
              // src is after the last in-order combining mark.
              // If there is a boundary here, then we continue with no change.
              if (norm16HasCompBoundaryBefore(n16)) {
                  if (isCompYesAndZeroCC(n16)) {
                      src = nextSrc;
                  }
                  continue;
              }
              // Use the slow path. There is no boundary in [prevSrc, src[.
          }
      }

      // Slow path: Find the nearest boundaries around the current character,
      // decompose and recompose.
      if (prevBoundary != prevSrc && !norm16HasCompBoundaryBefore(norm16)) {
          const UChar *p = prevSrc;
          UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, prevBoundary, p, c, norm16)do { (c) = *--(p); int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)!=0) && (p
) != (prevBoundary) && (((__c2 = *((p) - 1))&0xfffffc00
)==0xd800)) { --(p); (c) = (((UChar32)(__c2)<<10UL)+(UChar32
)((c))-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c)
 >= (normTrie)->highStart ? (normTrie)->dataLength -
 UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (norm16) = ((normTrie
)->data.ptr16[__index]); } while (false);
          if (!norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
              prevSrc = p;
          }
      }
      if (doCompose && prevBoundary != prevSrc && !buffer.appendZeroCC(prevBoundary, prevSrc, errorCode)) {
          break;
      }
      int32_t recomposeStartIndex=buffer.length();
      // We know there is not a boundary here.
      decomposeShort(prevSrc, src, FALSE0 /* !stopAtCompBoundary */, onlyContiguous,
                     buffer, errorCode);
      // Decompose until the next boundary.
      src = decomposeShort(src, limit, TRUE1 /* stopAtCompBoundary */, onlyContiguous,
                           buffer, errorCode);
      if (U_FAILURE(errorCode)) {
          break;
      }
      if ((src - prevSrc) > INT32_MAX(2147483647)) {  // guard before buffer.equals()
          errorCode = U_INDEX_OUTOFBOUNDS_ERROR;
          return TRUE1;
      }
      recompose(buffer, recomposeStartIndex, onlyContiguous);
      if(!doCompose) {
          if(!buffer.equals(prevSrc, src)) {
              return FALSE0;
          }
          buffer.remove();
      }
      prevBoundary=src;
  }
  return TRUE1;
1703}

1705// Very similar to compose(): Make the same changes in both places if relevant.
1706// pQCResult==NULL: spanQuickCheckYes
1707// pQCResult!=NULL: quickCheck (*pQCResult must be UNORM_YES)
1708const UChar *
1709Normalizer2Impl::composeQuickCheck(const UChar *src, const UChar *limit,
                                 UBool onlyContiguous,
                                 UNormalizationCheckResult *pQCResult) const {
  const UChar *prevBoundary=src;
  UChar32 minNoMaybeCP=minCompNoMaybeCP;
  if(limit==NULL__null) {
      UErrorCode errorCode=U_ZERO_ERROR;
      src=copyLowPrefixFromNulTerminated(src, minNoMaybeCP, NULL__null, errorCode);
      limit=u_strchru_strchr_71(src, 0);
      if (prevBoundary != src) {
          if (hasCompBoundaryAfter(*(src-1), onlyContiguous)) {
              prevBoundary = src;
          } else {
              prevBoundary = --src;
          }
      }
  }

  for(;;) {
      // Fast path: Scan over a sequence of characters below the minimum "no or maybe" code point,
      // or with (compYes && ccc==0) properties.
      const UChar *prevSrc;
      UChar32 c = 0;
      uint16_t norm16 = 0;
      for (;;) {
          if(src==limit) {
              return src;
          }
          if( (c=*src)<minNoMaybeCP ||
              isCompYesAndZeroCC(norm16=UCPTRIE_FAST_BMP_GET(normTrie, UCPTRIE_16, c)((normTrie)->data.ptr16[((int32_t)(normTrie)->index[(c)
 >> UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK
))]))
          ) {
              ++src;
          } else {
              prevSrc = src++;
              if(!U16_IS_LEAD(c)(((c)&0xfffffc00)==0xd800)) {
                  break;
              } else {
                  UChar c2;
                  if(src!=limit && U16_IS_TRAIL(c2=*src)(((c2=*src)&0xfffffc00)==0xdc00)) {
                      ++src;
                      c=U16_GET_SUPPLEMENTARY(c, c2)(((UChar32)(c)<<10UL)+(UChar32)(c2)-((0xd800<<10UL
)+0xdc00-0x10000));
                      norm16=UCPTRIE_FAST_SUPP_GET(normTrie, UCPTRIE_16, c)((normTrie)->data.ptr16[((c) >= (normTrie)->highStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c))]);
                      if(!isCompYesAndZeroCC(norm16)) {
                          break;
                      }
                  }
              }
          }
      }
      // isCompYesAndZeroCC(norm16) is false, that is, norm16>=minNoNo.
      // The current character is either a "noNo" (has a mapping)
      // or a "maybeYes" (combines backward)
      // or a "yesYes" with ccc!=0.
      // It is not a Hangul syllable or Jamo L because those have "yes" properties.

      uint16_t prevNorm16 = INERT;
      if (prevBoundary != prevSrc) {
          if (norm16HasCompBoundaryBefore(norm16)) {
              prevBoundary = prevSrc;
          } else {
              const UChar *p = prevSrc;
              uint16_t n16;
              UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, prevBoundary, p, c, n16)do { (c) = *--(p); int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)!=0) && (p
) != (prevBoundary) && (((__c2 = *((p) - 1))&0xfffffc00
)==0xd800)) { --(p); (c) = (((UChar32)(__c2)<<10UL)+(UChar32
)((c))-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c)
 >= (normTrie)->highStart ? (normTrie)->dataLength -
 UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (n16) = ((normTrie)
->data.ptr16[__index]); } while (false);
              if (norm16HasCompBoundaryAfter(n16, onlyContiguous)) {
                  prevBoundary = prevSrc;
              } else {
                  prevBoundary = p;
                  prevNorm16 = n16;
              }
          }
      }

      if(isMaybeOrNonZeroCC(norm16)) {
          uint8_t cc=getCCFromYesOrMaybe(norm16);
          if (onlyContiguous /* FCC */ && cc != 0 &&
                  getTrailCCFromCompYesAndZeroCC(prevNorm16) > cc) {
              // The [prevBoundary..prevSrc[ character
              // passed the quick check "yes && ccc==0" test
              // but is out of canonical order with the current combining mark.
          } else {
              // If !onlyContiguous (not FCC), then we ignore the tccc of
              // the previous character which passed the quick check "yes && ccc==0" test.
              const UChar *nextSrc;
              for (;;) {
                  if (norm16 < MIN_YES_YES_WITH_CC) {
                      if (pQCResult != nullptr) {
                          *pQCResult = UNORM_MAYBE;
                      } else {
                          return prevBoundary;
                      }
                  }
                  if (src == limit) {
                      return src;
                  }
                  uint8_t prevCC = cc;
                  nextSrc = src;
                  UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, nextSrc, limit, c, norm16)do { (c) = *(nextSrc)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (nextSrc
) != (limit) && (((__c2 = *(nextSrc))&0xfffffc00)
==0xdc00)) { ++(nextSrc); (c) = (((UChar32)((c))<<10UL)
+(UChar32)(__c2)-((0xd800<<10UL)+0xdc00-0x10000)); __index
 = ((c) >= (normTrie)->highStart ? (normTrie)->dataLength
 - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (norm16) = ((normTrie
)->data.ptr16[__index]); } while (false);
                  if (isMaybeOrNonZeroCC(norm16)) {
                      cc = getCCFromYesOrMaybe(norm16);
                      if (!(prevCC <= cc || cc == 0)) {
                          break;
                      }
                  } else {
                      break;
                  }
                  src = nextSrc;
              }
              // src is after the last in-order combining mark.
              if (isCompYesAndZeroCC(norm16)) {
                  prevBoundary = src;
                  src = nextSrc;
                  continue;
              }
          }
      }
      if(pQCResult!=NULL__null) {
          *pQCResult=UNORM_NO;
      }
      return prevBoundary;
  }
1829}

1831void Normalizer2Impl::composeAndAppend(const UChar *src, const UChar *limit,
                                     UBool doCompose,
                                     UBool onlyContiguous,
                                     UnicodeString &safeMiddle,
                                     ReorderingBuffer &buffer,
                                     UErrorCode &errorCode) const {
  if(!buffer.isEmpty()) {
      const UChar *firstStarterInSrc=findNextCompBoundary(src, limit, onlyContiguous);
      if(src!=firstStarterInSrc) {
          const UChar *lastStarterInDest=findPreviousCompBoundary(buffer.getStart(),
                                                                  buffer.getLimit(), onlyContiguous);
          int32_t destSuffixLength=(int32_t)(buffer.getLimit()-lastStarterInDest);
          UnicodeString middle(lastStarterInDest, destSuffixLength);
          buffer.removeSuffix(destSuffixLength);
          safeMiddle=middle;
          middle.append(src, (int32_t)(firstStarterInSrc-src));
          const UChar *middleStart=middle.getBuffer();
          compose(middleStart, middleStart+middle.length(), onlyContiguous,
                  TRUE1, buffer, errorCode);
          if(U_FAILURE(errorCode)) {
              return;
          }
          src=firstStarterInSrc;
      }
  }
  if(doCompose) {
      compose(src, limit, onlyContiguous, TRUE1, buffer, errorCode);
  } else {
      if(limit==NULL__null) {  // appendZeroCC() needs limit!=NULL
          limit=u_strchru_strchr_71(src, 0);
      }
      buffer.appendZeroCC(src, limit, errorCode);
  }
1864}

1866UBool
1867Normalizer2Impl::composeUTF8(uint32_t options, UBool onlyContiguous,
                           const uint8_t *src, const uint8_t *limit,
                           ByteSink *sink, Edits *edits, UErrorCode &errorCode) const {
  U_ASSERT(limit != nullptr)(void)0;
  UnicodeString s16;
  uint8_t minNoMaybeLead = leadByteForCP(minCompNoMaybeCP);
  const uint8_t *prevBoundary = src;

  for (;;) {
      // Fast path: Scan over a sequence of characters below the minimum "no or maybe" code point,
      // or with (compYes && ccc==0) properties.
      const uint8_t *prevSrc;
      uint16_t norm16 = 0;
      for (;;) {
          if (src == limit) {
              if (prevBoundary != limit && sink != nullptr) {
                  ByteSinkUtil::appendUnchanged(prevBoundary, limit,
                                                *sink, options, edits, errorCode);
              }
              return TRUE1;
          }
          if (*src < minNoMaybeLead) {
              ++src;
          } else {
              prevSrc = src;
              UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16)do { int32_t __lead = (uint8_t)*(src)++; if (!(((__lead)&
0x80)==0)) { uint8_t __t1, __t2, __t3; if ((src) != (limit) &&
 (__lead >= 0xe0 ? __lead < 0xf0 ? "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
[__lead &= 0xf] & (1 << ((__t1 = *(src)) >>
 5)) && ++(src) != (limit) && (__t2 = *(src) -
 0x80) <= 0x3f && (__lead = ((int32_t)(normTrie)->
index[(__lead << 6) + (__t1 & 0x3f)]) + __t2, 1) : (
__lead -= 0xf0) <= 4 && "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
[(__t1 = *(src)) >> 4] & (1 << __lead) &&
 (__lead = (__lead << 6) | (__t1 & 0x3f), ++(src) !=
 (limit)) && (__t2 = *(src) - 0x80) <= 0x3f &&
 ++(src) != (limit) && (__t3 = *(src) - 0x80) <= 0x3f
 && (__lead = __lead >= (normTrie)->shifted12HighStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallU8Index_71((normTrie), __lead, __t2, __t3
), 1) : __lead >= 0xc2 && (__t1 = *(src) - 0x80) <=
 0x3f && (__lead = (int32_t)(normTrie)->index[__lead
 & 0x1f] + __t1, 1))) { ++(src); } else { __lead = (normTrie
)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (
norm16) = ((normTrie)->data.ptr16[__lead]); } while (false
);
              if (!isCompYesAndZeroCC(norm16)) {
                  break;
              }
          }
      }
      // isCompYesAndZeroCC(norm16) is false, that is, norm16>=minNoNo.
      // The current character is either a "noNo" (has a mapping)
      // or a "maybeYes" (combines backward)
      // or a "yesYes" with ccc!=0.
      // It is not a Hangul syllable or Jamo L because those have "yes" properties.

      // Medium-fast path: Handle cases that do not require full decomposition and recomposition.
      if (!isMaybeOrNonZeroCC(norm16)) {  // minNoNo <= norm16 < minMaybeYes
          if (sink == nullptr) {
              return FALSE0;
          }
          // Fast path for mapping a character that is immediately surrounded by boundaries.
          // In this case, we need not decompose around the current character.
          if (isDecompNoAlgorithmic(norm16)) {
              // Maps to a single isCompYesAndZeroCC character
              // which also implies hasCompBoundaryBefore.
              if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
                      hasCompBoundaryBefore(src, limit)) {
                  if (prevBoundary != prevSrc &&
                          !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                         *sink, options, edits, errorCode)) {
                      break;
                  }
                  appendCodePointDelta(prevSrc, src, getAlgorithmicDelta(norm16), *sink, edits);
                  prevBoundary = src;
                  continue;
              }
          } else if (norm16 < minNoNoCompBoundaryBefore) {
              // The mapping is comp-normalized which also implies hasCompBoundaryBefore.
              if (norm16HasCompBoundaryAfter(norm16, onlyContiguous) ||
                      hasCompBoundaryBefore(src, limit)) {
                  if (prevBoundary != prevSrc &&
                          !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                         *sink, options, edits, errorCode)) {
                      break;
                  }
                  const uint16_t *mapping = getMapping(norm16);
                  int32_t length = *mapping++ & MAPPING_LENGTH_MASK;
                  if (!ByteSinkUtil::appendChange(prevSrc, src, (const UChar *)mapping, length,
                                                  *sink, edits, errorCode)) {
                      break;
                  }
                  prevBoundary = src;
                  continue;
              }
          } else if (norm16 >= minNoNoEmpty) {
              // The current character maps to nothing.
              // Simply omit it from the output if there is a boundary before _or_ after it.
              // The character itself implies no boundaries.
              if (hasCompBoundaryBefore(src, limit) ||
                      hasCompBoundaryAfter(prevBoundary, prevSrc, onlyContiguous)) {
                  if (prevBoundary != prevSrc &&
                          !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                         *sink, options, edits, errorCode)) {
                      break;
                  }
                  if (edits != nullptr) {
                      edits->addReplace((int32_t)(src - prevSrc), 0);
                  }
                  prevBoundary = src;
                  continue;
              }
          }
          // Other "noNo" type, or need to examine more text around this character:
          // Fall through to the slow path.
      } else if (isJamoVT(norm16)) {
          // Jamo L: E1 84 80..92
          // Jamo V: E1 85 A1..B5
          // Jamo T: E1 86 A8..E1 87 82
          U_ASSERT((src - prevSrc) == 3 && *prevSrc == 0xe1)(void)0;
          UChar32 prev = previousHangulOrJamo(prevBoundary, prevSrc);
          if (prevSrc[1] == 0x85) {
              // The current character is a Jamo Vowel,
              // compose with previous Jamo L and following Jamo T.
              UChar32 l = prev - Hangul::JAMO_L_BASE;
              if ((uint32_t)l < Hangul::JAMO_L_COUNT) {
                  if (sink == nullptr) {
                      return FALSE0;
                  }
                  int32_t t = getJamoTMinusBase(src, limit);
                  if (t >= 0) {
                      // The next character is a Jamo T.
                      src += 3;
                  } else if (hasCompBoundaryBefore(src, limit)) {
                      // No Jamo T follows, not even via decomposition.
                      t = 0;
                  }
                  if (t >= 0) {
                      UChar32 syllable = Hangul::HANGUL_BASE +
                          (l*Hangul::JAMO_V_COUNT + (prevSrc[2]-0xa1)) *
                          Hangul::JAMO_T_COUNT + t;
                      prevSrc -= 3;  // Replace the Jamo L as well.
                      if (prevBoundary != prevSrc &&
                              !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                             *sink, options, edits, errorCode)) {
                          break;
                      }
                      ByteSinkUtil::appendCodePoint(prevSrc, src, syllable, *sink, edits);
                      prevBoundary = src;
                      continue;
                  }
                  // If we see L+V+x where x!=T then we drop to the slow path,
                  // decompose and recompose.
                  // This is to deal with NFKC finding normal L and V but a
                  // compatibility variant of a T.
                  // We need to either fully compose that combination here
                  // (which would complicate the code and may not work with strange custom data)
                  // or use the slow path.
              }
          } else if (Hangul::isHangulLV(prev)) {
              // The current character is a Jamo Trailing consonant,
              // compose with previous Hangul LV that does not contain a Jamo T.
              if (sink == nullptr) {
                  return FALSE0;
              }
              UChar32 syllable = prev + getJamoTMinusBase(prevSrc, src);
              prevSrc -= 3;  // Replace the Hangul LV as well.
              if (prevBoundary != prevSrc &&
                      !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                     *sink, options, edits, errorCode)) {
                  break;
              }
              ByteSinkUtil::appendCodePoint(prevSrc, src, syllable, *sink, edits);
              prevBoundary = src;
              continue;
          }
          // No matching context, or may need to decompose surrounding text first:
          // Fall through to the slow path.
      } else if (norm16 > JAMO_VT) {  // norm16 >= MIN_YES_YES_WITH_CC
          // One or more combining marks that do not combine-back:
          // Check for canonical order, copy unchanged if ok and
          // if followed by a character with a boundary-before.
          uint8_t cc = getCCFromNormalYesOrMaybe(norm16);  // cc!=0
          if (onlyContiguous /* FCC */ && getPreviousTrailCC(prevBoundary, prevSrc) > cc) {
              // Fails FCD test, need to decompose and contiguously recompose.
              if (sink == nullptr) {
                  return FALSE0;
              }
          } else {
              // If !onlyContiguous (not FCC), then we ignore the tccc of
              // the previous character which passed the quick check "yes && ccc==0" test.
              const uint8_t *nextSrc;
              uint16_t n16;
              for (;;) {
                  if (src == limit) {
                      if (sink != nullptr) {
                          ByteSinkUtil::appendUnchanged(prevBoundary, limit,
                                                        *sink, options, edits, errorCode);
                      }
                      return TRUE1;
                  }
                  uint8_t prevCC = cc;
                  nextSrc = src;
                  UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, nextSrc, limit, n16)do { int32_t __lead = (uint8_t)*(nextSrc)++; if (!(((__lead)&
0x80)==0)) { uint8_t __t1, __t2, __t3; if ((nextSrc) != (limit
) && (__lead >= 0xe0 ? __lead < 0xf0 ? "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
[__lead &= 0xf] & (1 << ((__t1 = *(nextSrc)) >>
 5)) && ++(nextSrc) != (limit) && (__t2 = *(nextSrc
) - 0x80) <= 0x3f && (__lead = ((int32_t)(normTrie
)->index[(__lead << 6) + (__t1 & 0x3f)]) + __t2,
 1) : (__lead -= 0xf0) <= 4 && "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
[(__t1 = *(nextSrc)) >> 4] & (1 << __lead) &&
 (__lead = (__lead << 6) | (__t1 & 0x3f), ++(nextSrc
) != (limit)) && (__t2 = *(nextSrc) - 0x80) <= 0x3f
 && ++(nextSrc) != (limit) && (__t3 = *(nextSrc
) - 0x80) <= 0x3f && (__lead = __lead >= (normTrie
)->shifted12HighStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallU8Index_71((normTrie), __lead, __t2, __t3
), 1) : __lead >= 0xc2 && (__t1 = *(nextSrc) - 0x80
) <= 0x3f && (__lead = (int32_t)(normTrie)->index
[__lead & 0x1f] + __t1, 1))) { ++(nextSrc); } else { __lead
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (n16) = ((normTrie)->data.ptr16[__lead]); } while (false
);
                  if (n16 >= MIN_YES_YES_WITH_CC) {
                      cc = getCCFromNormalYesOrMaybe(n16);
                      if (prevCC > cc) {
                          if (sink == nullptr) {
                              return FALSE0;
                          }
                          break;
                      }
                  } else {
                      break;
                  }
                  src = nextSrc;
              }
              // src is after the last in-order combining mark.
              // If there is a boundary here, then we continue with no change.
              if (norm16HasCompBoundaryBefore(n16)) {
                  if (isCompYesAndZeroCC(n16)) {
                      src = nextSrc;
                  }
                  continue;
              }
              // Use the slow path. There is no boundary in [prevSrc, src[.
          }
      }

      // Slow path: Find the nearest boundaries around the current character,
      // decompose and recompose.
      if (prevBoundary != prevSrc && !norm16HasCompBoundaryBefore(norm16)) {
          const uint8_t *p = prevSrc;
          UCPTRIE_FAST_U8_PREV(normTrie, UCPTRIE_16, prevBoundary, p, norm16)do { int32_t __index = (uint8_t)*--(p); if (!(((__index)&
0x80)==0)) { __index = ucptrie_internalU8PrevIndex_71((normTrie
), __index, (const uint8_t *)(prevBoundary), (const uint8_t *
)(p)); (p) -= __index & 7; __index >>= 3; } (norm16
) = ((normTrie)->data.ptr16[__index]); } while (false);
          if (!norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
              prevSrc = p;
          }
      }
      ReorderingBuffer buffer(*this, s16, errorCode);
      if (U_FAILURE(errorCode)) {
          break;
      }
      // We know there is not a boundary here.
      decomposeShort(prevSrc, src, STOP_AT_LIMIT, onlyContiguous,
                     buffer, errorCode);
      // Decompose until the next boundary.
      src = decomposeShort(src, limit, STOP_AT_COMP_BOUNDARY, onlyContiguous,
                           buffer, errorCode);
      if (U_FAILURE(errorCode)) {
          break;
      }
      if ((src - prevSrc) > INT32_MAX(2147483647)) {  // guard before buffer.equals()
          errorCode = U_INDEX_OUTOFBOUNDS_ERROR;
          return TRUE1;
      }
      recompose(buffer, 0, onlyContiguous);
      if (!buffer.equals(prevSrc, src)) {
          if (sink == nullptr) {
              return FALSE0;
          }
          if (prevBoundary != prevSrc &&
                  !ByteSinkUtil::appendUnchanged(prevBoundary, prevSrc,
                                                 *sink, options, edits, errorCode)) {
              break;
          }
          if (!ByteSinkUtil::appendChange(prevSrc, src, buffer.getStart(), buffer.length(),
                                          *sink, edits, errorCode)) {
              break;
          }
          prevBoundary = src;
      }
  }
  return TRUE1;
2121}

2123UBool Normalizer2Impl::hasCompBoundaryBefore(const UChar *src, const UChar *limit) const {
  if (src == limit || *src < minCompNoMaybeCP) {
      return TRUE1;
  }
  UChar32 c;
  uint16_t norm16;
  UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, src, limit, c, norm16)do { (c) = *(src)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (src
) != (limit) && (((__c2 = *(src))&0xfffffc00)==0xdc00
)) { ++(src); (c) = (((UChar32)((c))<<10UL)+(UChar32)(__c2
)-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c) >=
 (normTrie)->highStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c)); } else { __index
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (norm16) = ((normTrie)->data.ptr16[__index]); } while
 (false);
  return norm16HasCompBoundaryBefore(norm16);
2131}

2133UBool Normalizer2Impl::hasCompBoundaryBefore(const uint8_t *src, const uint8_t *limit) const {
  if (src == limit) {
      return TRUE1;
  }
  uint16_t norm16;
  UCPTRIE_FAST_U8_NEXT(normTrie, UCPTRIE_16, src, limit, norm16)do { int32_t __lead = (uint8_t)*(src)++; if (!(((__lead)&
0x80)==0)) { uint8_t __t1, __t2, __t3; if ((src) != (limit) &&
 (__lead >= 0xe0 ? __lead < 0xf0 ? "\x20\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x30\x10\x30\x30"
[__lead &= 0xf] & (1 << ((__t1 = *(src)) >>
 5)) && ++(src) != (limit) && (__t2 = *(src) -
 0x80) <= 0x3f && (__lead = ((int32_t)(normTrie)->
index[(__lead << 6) + (__t1 & 0x3f)]) + __t2, 1) : (
__lead -= 0xf0) <= 4 && "\x00\x00\x00\x00\x00\x00\x00\x00\x1E\x0F\x0F\x0F\x00\x00\x00\x00"
[(__t1 = *(src)) >> 4] & (1 << __lead) &&
 (__lead = (__lead << 6) | (__t1 & 0x3f), ++(src) !=
 (limit)) && (__t2 = *(src) - 0x80) <= 0x3f &&
 ++(src) != (limit) && (__t3 = *(src) - 0x80) <= 0x3f
 && (__lead = __lead >= (normTrie)->shifted12HighStart
 ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallU8Index_71((normTrie), __lead, __t2, __t3
), 1) : __lead >= 0xc2 && (__t1 = *(src) - 0x80) <=
 0x3f && (__lead = (int32_t)(normTrie)->index[__lead
 & 0x1f] + __t1, 1))) { ++(src); } else { __lead = (normTrie
)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (
norm16) = ((normTrie)->data.ptr16[__lead]); } while (false
);
  return norm16HasCompBoundaryBefore(norm16);
2140}

2142UBool Normalizer2Impl::hasCompBoundaryAfter(const UChar *start, const UChar *p,
                                          UBool onlyContiguous) const {
  if (start == p) {
      return TRUE1;
  }
  UChar32 c;
  uint16_t norm16;
  UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, start, p, c, norm16)do { (c) = *--(p); int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)!=0) && (p
) != (start) && (((__c2 = *((p) - 1))&0xfffffc00)
==0xd800)) { --(p); (c) = (((UChar32)(__c2)<<10UL)+(UChar32
)((c))-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c)
 >= (normTrie)->highStart ? (normTrie)->dataLength -
 UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (norm16) = ((normTrie
)->data.ptr16[__index]); } while (false);
  return norm16HasCompBoundaryAfter(norm16, onlyContiguous);
2151}

2153UBool Normalizer2Impl::hasCompBoundaryAfter(const uint8_t *start, const uint8_t *p,
                                          UBool onlyContiguous) const {
  if (start == p) {
      return TRUE1;
  }
  uint16_t norm16;
  UCPTRIE_FAST_U8_PREV(normTrie, UCPTRIE_16, start, p, norm16)do { int32_t __index = (uint8_t)*--(p); if (!(((__index)&
0x80)==0)) { __index = ucptrie_internalU8PrevIndex_71((normTrie
), __index, (const uint8_t *)(start), (const uint8_t *)(p)); (
p) -= __index & 7; __index >>= 3; } (norm16) = ((normTrie
)->data.ptr16[__index]); } while (false);
  return norm16HasCompBoundaryAfter(norm16, onlyContiguous);
2161}

2163const UChar *Normalizer2Impl::findPreviousCompBoundary(const UChar *start, const UChar *p,
                                                     UBool onlyContiguous) const {
  while (p != start) {
      const UChar *codePointLimit = p;
      UChar32 c;
      uint16_t norm16;
      UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, start, p, c, norm16)do { (c) = *--(p); int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)!=0) && (p
) != (start) && (((__c2 = *((p) - 1))&0xfffffc00)
==0xd800)) { --(p); (c) = (((UChar32)(__c2)<<10UL)+(UChar32
)((c))-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c)
 >= (normTrie)->highStart ? (normTrie)->dataLength -
 UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (norm16) = ((normTrie
)->data.ptr16[__index]); } while (false);
      if (norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
          return codePointLimit;
      }
      if (hasCompBoundaryBefore(c, norm16)) {
          return p;
      }
  }
  return p;
2178}

2180const UChar *Normalizer2Impl::findNextCompBoundary(const UChar *p, const UChar *limit,
                                                 UBool onlyContiguous) const {
  while (p != limit) {
      const UChar *codePointStart = p;
      UChar32 c;
      uint16_t norm16;
      UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16)do { (c) = *(p)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (p
) != (limit) && (((__c2 = *(p))&0xfffffc00)==0xdc00
)) { ++(p); (c) = (((UChar32)((c))<<10UL)+(UChar32)(__c2
)-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c) >=
 (normTrie)->highStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c)); } else { __index
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (norm16) = ((normTrie)->data.ptr16[__index]); } while
 (false);
      if (hasCompBoundaryBefore(c, norm16)) {
          return codePointStart;
      }
      if (norm16HasCompBoundaryAfter(norm16, onlyContiguous)) {
          return p;
      }
  }
  return p;
2195}

2197uint8_t Normalizer2Impl::getPreviousTrailCC(const UChar *start, const UChar *p) const {
  if (start == p) {
      return 0;
  }
  int32_t i = (int32_t)(p - start);
  UChar32 c;
  U16_PREV(start, 0, i, c)do { (c)=(start)[--(i)]; if((((c)&0xfffffc00)==0xdc00)) {
 uint16_t __c2; if((i)>(0) && (((__c2=(start)[(i)-
1])&0xfffffc00)==0xd800)) { --(i); (c)=(((UChar32)(__c2)<<
10UL)+(UChar32)((c))-((0xd800<<10UL)+0xdc00-0x10000)); }
 } } while (false);
  return (uint8_t)getFCD16(c);
2205}

2207uint8_t Normalizer2Impl::getPreviousTrailCC(const uint8_t *start, const uint8_t *p) const {
  if (start == p) {
      return 0;
  }
  int32_t i = (int32_t)(p - start);
  UChar32 c;
  U8_PREV(start, 0, i, c)do { (c)=(uint8_t)(start)[--(i)]; if(!(((c)&0x80)==0)) { (
c)=utf8_prevCharSafeBody_71((const uint8_t *)start, 0, &(
i), c, -1); } } while (false);
  return (uint8_t)getFCD16(c);
2215}

2217// Note: normalizer2impl.cpp r30982 (2011-nov-27)
2218// still had getFCDTrie() which built and cached an FCD trie.
2219// That provided faster access to FCD data than getFCD16FromNormData()
2220// but required synchronization and consumed some 10kB of heap memory
2221// in any process that uses FCD (e.g., via collation).
2222// minDecompNoCP etc. and smallFCD[] are intended to help with any loss of performance,
2223// at least for ASCII & CJK.

2225// Ticket 20907 - The optimizer in MSVC/Visual Studio versions below 16.4 has trouble with this
2226// function on Windows ARM64. As a work-around, we disable optimizations for this function.
2227// This work-around could/should be removed once the following versions of Visual Studio are no
2228// longer supported: All versions of VS2017, and versions of VS2019 below 16.4.
2229#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
2230#pragma optimize( "", off )
2231#endif
2232// Gets the FCD value from the regular normalization data.
2233uint16_t Normalizer2Impl::getFCD16FromNormData(UChar32 c) const {
  uint16_t norm16=getNorm16(c);
  if (norm16 >= limitNoNo) {
      if(norm16>=MIN_NORMAL_MAYBE_YES) {
          // combining mark
          norm16=getCCFromNormalYesOrMaybe(norm16);
          return norm16|(norm16<<8);
      } else if(norm16>=minMaybeYes) {
          return 0;
      } else {  // isDecompNoAlgorithmic(norm16)
          uint16_t deltaTrailCC = norm16 & DELTA_TCCC_MASK;
          if (deltaTrailCC <= DELTA_TCCC_1) {
              return deltaTrailCC >> OFFSET_SHIFT;
          }
          // Maps to an isCompYesAndZeroCC.
          c=mapAlgorithmic(c, norm16);
          norm16=getRawNorm16(c);
      }
  }
  if(norm16<=minYesNo || isHangulLVT(norm16)) {
      // no decomposition or Hangul syllable, all zeros
      return 0;
  }
  // c decomposes, get everything from the variable-length extra data
  const uint16_t *mapping=getMapping(norm16);
  uint16_t firstUnit=*mapping;
  norm16=firstUnit>>8;  // tccc
  if(firstUnit&MAPPING_HAS_CCC_LCCC_WORD) {
      norm16|=*(mapping-1)&0xff00;  // lccc
  }
  return norm16;
2264}
2265#if (defined(_MSC_VER) && (defined(_M_ARM64)) && (_MSC_VER < 1924))
2266#pragma optimize( "", on )
2267#endif

2269// Dual functionality:
2270// buffer!=NULL: normalize
2271// buffer==NULL: isNormalized/quickCheck/spanQuickCheckYes
2272const UChar *
2273Normalizer2Impl::makeFCD(const UChar *src, const UChar *limit,
                       ReorderingBuffer *buffer,
                       UErrorCode &errorCode) const {
  // Tracks the last FCD-safe boundary, before lccc=0 or after properly-ordered tccc<=1.
  // Similar to the prevBoundary in the compose() implementation.
  const UChar *prevBoundary=src;
  int32_t prevFCD16=0;
  if(limit3.1
'limit' is equal to NULL
==NULL__null) {
4
←
Taking true branch→
      src=copyLowPrefixFromNulTerminated(src, minLcccCP, buffer, errorCode);
5
←
Calling 'Normalizer2Impl::copyLowPrefixFromNulTerminated'→
      if(U_FAILURE(errorCode)) {
          return src;
      }
      if(prevBoundary<src) {
          prevBoundary=src;
          // We know that the previous character's lccc==0.
          // Fetching the fcd16 value was deferred for this below-U+0300 code point.
          prevFCD16=getFCD16(*(src-1));
          if(prevFCD16>1) {
              --prevBoundary;
          }
      }
      limit=u_strchru_strchr_71(src, 0);
  }

  // Note: In this function we use buffer->appendZeroCC() because we track
  // the lead and trail combining classes here, rather than leaving it to
  // the ReorderingBuffer.
  // The exception is the call to decomposeShort() which uses the buffer
  // in the normal way.

  const UChar *prevSrc;
  UChar32 c=0;
  uint16_t fcd16=0;

  for(;;) {
      // count code units with lccc==0
      for(prevSrc=src; src!=limit;) {
          if((c=*src)<minLcccCP) {
              prevFCD16=~c;
              ++src;
          } else if(!singleLeadMightHaveNonZeroFCD16(c)) {
              prevFCD16=0;
              ++src;
          } else {
              if(U16_IS_LEAD(c)(((c)&0xfffffc00)==0xd800)) {
                  UChar c2;
                  if((src+1)!=limit && U16_IS_TRAIL(c2=src[1])(((c2=src[1])&0xfffffc00)==0xdc00)) {
                      c=U16_GET_SUPPLEMENTARY(c, c2)(((UChar32)(c)<<10UL)+(UChar32)(c2)-((0xd800<<10UL
)+0xdc00-0x10000));
                  }
              }
              if((fcd16=getFCD16FromNormData(c))<=0xff) {
                  prevFCD16=fcd16;
                  src+=U16_LENGTH(c)((uint32_t)(c)<=0xffff ? 1 : 2);
              } else {
                  break;
              }
          }
      }
      // copy these code units all at once
      if(src!=prevSrc) {
          if(buffer!=NULL__null && !buffer->appendZeroCC(prevSrc, src, errorCode)) {
              break;
          }
          if(src==limit) {
              break;
          }
          prevBoundary=src;
          // We know that the previous character's lccc==0.
          if(prevFCD16<0) {
              // Fetching the fcd16 value was deferred for this below-minLcccCP code point.
              UChar32 prev=~prevFCD16;
              if(prev<minDecompNoCP) {
                  prevFCD16=0;
              } else {
                  prevFCD16=getFCD16FromNormData(prev);
                  if(prevFCD16>1) {
                      --prevBoundary;
                  }
              }
          } else {
              const UChar *p=src-1;
              if(U16_IS_TRAIL(*p)(((*p)&0xfffffc00)==0xdc00) && prevSrc<p && U16_IS_LEAD(*(p-1))(((*(p-1))&0xfffffc00)==0xd800)) {
                  --p;
                  // Need to fetch the previous character's FCD value because
                  // prevFCD16 was just for the trail surrogate code point.
                  prevFCD16=getFCD16FromNormData(U16_GET_SUPPLEMENTARY(p[0], p[1])(((UChar32)(p[0])<<10UL)+(UChar32)(p[1])-((0xd800<<
10UL)+0xdc00-0x10000)));
                  // Still known to have lccc==0 because its lead surrogate unit had lccc==0.
              }
              if(prevFCD16>1) {
                  prevBoundary=p;
              }
          }
          // The start of the current character (c).
          prevSrc=src;
      } else if(src==limit) {
          break;
      }

      src+=U16_LENGTH(c)((uint32_t)(c)<=0xffff ? 1 : 2);
      // The current character (c) at [prevSrc..src[ has a non-zero lead combining class.
      // Check for proper order, and decompose locally if necessary.
      if((prevFCD16&0xff)<=(fcd16>>8)) {
          // proper order: prev tccc <= current lccc
          if((fcd16&0xff)<=1) {
              prevBoundary=src;
          }
          if(buffer!=NULL__null && !buffer->appendZeroCC(c, errorCode)) {
              break;
          }
          prevFCD16=fcd16;
          continue;
      } else if(buffer==NULL__null) {
          return prevBoundary;  // quick check "no"
      } else {
          /*
           * Back out the part of the source that we copied or appended
           * already but is now going to be decomposed.
           * prevSrc is set to after what was copied/appended.
           */
          buffer->removeSuffix((int32_t)(prevSrc-prevBoundary));
          /*
           * Find the part of the source that needs to be decomposed,
           * up to the next safe boundary.
           */
          src=findNextFCDBoundary(src, limit);
          /*
           * The source text does not fulfill the conditions for FCD.
           * Decompose and reorder a limited piece of the text.
           */
          decomposeShort(prevBoundary, src, FALSE0, FALSE0, *buffer, errorCode);
          if (U_FAILURE(errorCode)) {
              break;
          }
          prevBoundary=src;
          prevFCD16=0;
      }
  }
  return src;
2411}

2413void Normalizer2Impl::makeFCDAndAppend(const UChar *src, const UChar *limit,
                                     UBool doMakeFCD,
                                     UnicodeString &safeMiddle,
                                     ReorderingBuffer &buffer,
                                     UErrorCode &errorCode) const {
  if(!buffer.isEmpty()) {
1
Taking true branch→
      const UChar *firstBoundaryInSrc=findNextFCDBoundary(src, limit);
      if(src1.1
'src' is not equal to 'firstBoundaryInSrc'
!=firstBoundaryInSrc) {
2
←
Taking true branch→
          const UChar *lastBoundaryInDest=findPreviousFCDBoundary(buffer.getStart(),
                                                                  buffer.getLimit());
          int32_t destSuffixLength=(int32_t)(buffer.getLimit()-lastBoundaryInDest);
          UnicodeString middle(lastBoundaryInDest, destSuffixLength);
          buffer.removeSuffix(destSuffixLength);
          safeMiddle=middle;
          middle.append(src, (int32_t)(firstBoundaryInSrc-src));
          const UChar *middleStart=middle.getBuffer();
          makeFCD(middleStart, middleStart+middle.length(), &buffer, errorCode);
3
←
Calling 'Normalizer2Impl::makeFCD'→
          if(U_FAILURE(errorCode)) {
              return;
          }
          src=firstBoundaryInSrc;
      }
  }
  if(doMakeFCD) {
      makeFCD(src, limit, &buffer, errorCode);
  } else {
      if(limit==NULL__null) {  // appendZeroCC() needs limit!=NULL
          limit=u_strchru_strchr_71(src, 0);
      }
      buffer.appendZeroCC(src, limit, errorCode);
  }
2444}

2446const UChar *Normalizer2Impl::findPreviousFCDBoundary(const UChar *start, const UChar *p) const {
  while(start<p) {
      const UChar *codePointLimit = p;
      UChar32 c;
      uint16_t norm16;
      UCPTRIE_FAST_U16_PREV(normTrie, UCPTRIE_16, start, p, c, norm16)do { (c) = *--(p); int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)!=0) && (p
) != (start) && (((__c2 = *((p) - 1))&0xfffffc00)
==0xd800)) { --(p); (c) = (((UChar32)(__c2)<<10UL)+(UChar32
)((c))-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c)
 >= (normTrie)->highStart ? (normTrie)->dataLength -
 UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET : ucptrie_internalSmallIndex_71
(normTrie, c)); } else { __index = (normTrie)->dataLength -
 UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET; } } (norm16) = ((normTrie
)->data.ptr16[__index]); } while (false);
      if (c < minDecompNoCP || norm16HasDecompBoundaryAfter(norm16)) {
          return codePointLimit;
      }
      if (norm16HasDecompBoundaryBefore(norm16)) {
          return p;
      }
  }
  return p;
2460}

2462const UChar *Normalizer2Impl::findNextFCDBoundary(const UChar *p, const UChar *limit) const {
  while(p<limit) {
      const UChar *codePointStart=p;
      UChar32 c;
      uint16_t norm16;
      UCPTRIE_FAST_U16_NEXT(normTrie, UCPTRIE_16, p, limit, c, norm16)do { (c) = *(p)++; int32_t __index; if (!(((c)&0xfffff800
)==0xd800)) { __index = ((int32_t)(normTrie)->index[(c) >>
 UCPTRIE_FAST_SHIFT] + ((c) & UCPTRIE_FAST_DATA_MASK)); }
 else { uint16_t __c2; if ((((c)&0x400)==0) && (p
) != (limit) && (((__c2 = *(p))&0xfffffc00)==0xdc00
)) { ++(p); (c) = (((UChar32)((c))<<10UL)+(UChar32)(__c2
)-((0xd800<<10UL)+0xdc00-0x10000)); __index = ((c) >=
 (normTrie)->highStart ? (normTrie)->dataLength - UCPTRIE_HIGH_VALUE_NEG_DATA_OFFSET
 : ucptrie_internalSmallIndex_71(normTrie, c)); } else { __index
 = (normTrie)->dataLength - UCPTRIE_ERROR_VALUE_NEG_DATA_OFFSET
; } } (norm16) = ((normTrie)->data.ptr16[__index]); } while
 (false);
      if (c < minLcccCP || norm16HasDecompBoundaryBefore(norm16)) {
          return codePointStart;
      }
      if (norm16HasDecompBoundaryAfter(norm16)) {
          return p;
      }
  }
  return p;
2476}

2478// CanonicalIterator data -------------------------------------------------- ***

2480CanonIterData::CanonIterData(UErrorCode &errorCode) :
      mutableTrie(umutablecptrie_openumutablecptrie_open_71(0, 0, &errorCode)), trie(nullptr),
      canonStartSets(uprv_deleteUObjectuprv_deleteUObject_71, NULL__null, errorCode) {}

2484CanonIterData::~CanonIterData() {
  umutablecptrie_closeumutablecptrie_close_71(mutableTrie);
  ucptrie_closeucptrie_close_71(trie);
2487}

2489void CanonIterData::addToStartSet(UChar32 origin, UChar32 decompLead, UErrorCode &errorCode) {
  uint32_t canonValue = umutablecptrie_getumutablecptrie_get_71(mutableTrie, decompLead);
  if((canonValue&(CANON_HAS_SET0x200000|CANON_VALUE_MASK0x1fffff))==0 && origin!=0) {
      // origin is the first character whose decomposition starts with
      // the character for which we are setting the value.
      umutablecptrie_setumutablecptrie_set_71(mutableTrie, decompLead, canonValue|origin, &errorCode);
  } else {
      // origin is not the first character, or it is U+0000.
      UnicodeSet *set;
      if((canonValue&CANON_HAS_SET0x200000)==0) {
          LocalPointer<UnicodeSet> lpSet(new UnicodeSet, errorCode);
          set=lpSet.getAlias();
          if(U_FAILURE(errorCode)) {
              return;
          }
          UChar32 firstOrigin=(UChar32)(canonValue&CANON_VALUE_MASK0x1fffff);
          canonValue=(canonValue&~CANON_VALUE_MASK0x1fffff)|CANON_HAS_SET0x200000|(uint32_t)canonStartSets.size();
          umutablecptrie_setumutablecptrie_set_71(mutableTrie, decompLead, canonValue, &errorCode);
          canonStartSets.adoptElement(lpSet.orphan(), errorCode);
          if (U_FAILURE(errorCode)) {
              return;
          }
          if(firstOrigin!=0) {
              set->add(firstOrigin);
          }
      } else {
          set=(UnicodeSet *)canonStartSets[(int32_t)(canonValue&CANON_VALUE_MASK0x1fffff)];
      }
      set->add(origin);
  }
2519}

2521// C++ class for friend access to private Normalizer2Impl members.
2522class InitCanonIterData {
2523public:
  static void doInit(Normalizer2Impl *impl, UErrorCode &errorCode);
2525};

2527U_CDECL_BEGINextern "C" {

2529// UInitOnce instantiation function for CanonIterData
2530static void U_CALLCONV
2531initCanonIterData(Normalizer2Impl *impl, UErrorCode &errorCode) {
  InitCanonIterData::doInit(impl, errorCode);
2533}

2535U_CDECL_END}

2537void InitCanonIterData::doInit(Normalizer2Impl *impl, UErrorCode &errorCode) {
  U_ASSERT(impl->fCanonIterData == NULL)(void)0;
  impl->fCanonIterData = new CanonIterData(errorCode);
  if (impl->fCanonIterData == NULL__null) {
      errorCode=U_MEMORY_ALLOCATION_ERROR;
  }
  if (U_SUCCESS(errorCode)) {
      UChar32 start = 0, end;
      uint32_t value;
      while ((end = ucptrie_getRangeucptrie_getRange_71(impl->normTrie, start,
                                     UCPMAP_RANGE_FIXED_LEAD_SURROGATES, Normalizer2Impl::INERT,
                                     nullptr, nullptr, &value)) >= 0) {
          // Call Normalizer2Impl::makeCanonIterDataFromNorm16() for a range of same-norm16 characters.
          if (value != Normalizer2Impl::INERT) {
              impl->makeCanonIterDataFromNorm16(start, end, value, *impl->fCanonIterData, errorCode);
          }
          start = end + 1;
      }
2555#ifdef UCPTRIE_DEBUG
      umutablecptrie_setName(impl->fCanonIterData->mutableTrie, "CanonIterData");
2557#endif
      impl->fCanonIterData->trie = umutablecptrie_buildImmutableumutablecptrie_buildImmutable_71(
          impl->fCanonIterData->mutableTrie, UCPTRIE_TYPE_SMALL, UCPTRIE_VALUE_BITS_32, &errorCode);
      umutablecptrie_closeumutablecptrie_close_71(impl->fCanonIterData->mutableTrie);
      impl->fCanonIterData->mutableTrie = nullptr;
  }
  if (U_FAILURE(errorCode)) {
      delete impl->fCanonIterData;
      impl->fCanonIterData = NULL__null;
  }
2567}

2569void Normalizer2Impl::makeCanonIterDataFromNorm16(UChar32 start, UChar32 end, const uint16_t norm16,
                                                CanonIterData &newData,
                                                UErrorCode &errorCode) const {
  if(isInert(norm16) || (minYesNo<=norm16 && norm16<minNoNo)) {
      // Inert, or 2-way mapping (including Hangul syllable).
      // We do not write a canonStartSet for any yesNo character.
      // Composites from 2-way mappings are added at runtime from the
      // starter's compositions list, and the other characters in
      // 2-way mappings get CANON_NOT_SEGMENT_STARTER set because they are
      // "maybe" characters.
      return;
  }
  for(UChar32 c=start; c<=end; ++c) {
      uint32_t oldValue = umutablecptrie_getumutablecptrie_get_71(newData.mutableTrie, c);
      uint32_t newValue=oldValue;
      if(isMaybeOrNonZeroCC(norm16)) {
          // not a segment starter if it occurs in a decomposition or has cc!=0
          newValue|=CANON_NOT_SEGMENT_STARTER0x80000000;
          if(norm16<MIN_NORMAL_MAYBE_YES) {
              newValue|=CANON_HAS_COMPOSITIONS0x40000000;
          }
      } else if(norm16<minYesNo) {
          newValue|=CANON_HAS_COMPOSITIONS0x40000000;
      } else {
          // c has a one-way decomposition
          UChar32 c2=c;
          // Do not modify the whole-range norm16 value.
          uint16_t norm16_2=norm16;
          if (isDecompNoAlgorithmic(norm16_2)) {
              // Maps to an isCompYesAndZeroCC.
              c2 = mapAlgorithmic(c2, norm16_2);
              norm16_2 = getRawNorm16(c2);
              // No compatibility mappings for the CanonicalIterator.
              U_ASSERT(!(isHangulLV(norm16_2) || isHangulLVT(norm16_2)))(void)0;
          }
          if (norm16_2 > minYesNo) {
              // c decomposes, get everything from the variable-length extra data
              const uint16_t *mapping=getMapping(norm16_2);
              uint16_t firstUnit=*mapping;
              int32_t length=firstUnit&MAPPING_LENGTH_MASK;
              if((firstUnit&MAPPING_HAS_CCC_LCCC_WORD)!=0) {
                  if(c==c2 && (*(mapping-1)&0xff)!=0) {
                      newValue|=CANON_NOT_SEGMENT_STARTER0x80000000;  // original c has cc!=0
                  }
              }
              // Skip empty mappings (no characters in the decomposition).
              if(length!=0) {
                  ++mapping;  // skip over the firstUnit
                  // add c to first code point's start set
                  int32_t i=0;
                  U16_NEXT_UNSAFE(mapping, i, c2)do { (c2)=(mapping)[(i)++]; if((((c2)&0xfffffc00)==0xd800
)) { (c2)=(((UChar32)((c2))<<10UL)+(UChar32)((mapping)[
(i)++])-((0xd800<<10UL)+0xdc00-0x10000)); } } while (false
);
                  newData.addToStartSet(c, c2, errorCode);
                  // Set CANON_NOT_SEGMENT_STARTER for each remaining code point of a
                  // one-way mapping. A 2-way mapping is possible here after
                  // intermediate algorithmic mapping.
                  if(norm16_2>=minNoNo) {
                      while(i<length) {
                          U16_NEXT_UNSAFE(mapping, i, c2)do { (c2)=(mapping)[(i)++]; if((((c2)&0xfffffc00)==0xd800
)) { (c2)=(((UChar32)((c2))<<10UL)+(UChar32)((mapping)[
(i)++])-((0xd800<<10UL)+0xdc00-0x10000)); } } while (false
);
                          uint32_t c2Value = umutablecptrie_getumutablecptrie_get_71(newData.mutableTrie, c2);
                          if((c2Value&CANON_NOT_SEGMENT_STARTER0x80000000)==0) {
                              umutablecptrie_setumutablecptrie_set_71(newData.mutableTrie, c2,
                                                 c2Value|CANON_NOT_SEGMENT_STARTER0x80000000, &errorCode);
                          }
                      }
                  }
              }
          } else {
              // c decomposed to c2 algorithmically; c has cc==0
              newData.addToStartSet(c, c2, errorCode);
          }
      }
      if(newValue!=oldValue) {
          umutablecptrie_setumutablecptrie_set_71(newData.mutableTrie, c, newValue, &errorCode);
      }
  }
2644}

2646UBool Normalizer2Impl::ensureCanonIterData(UErrorCode &errorCode) const {
  // Logically const: Synchronized instantiation.
  Normalizer2Impl *me=const_cast<Normalizer2Impl *>(this);
  umtx_initOnce(me->fCanonIterDataInitOnce, &initCanonIterData, me, errorCode);
  return U_SUCCESS(errorCode);
2651}

2653int32_t Normalizer2Impl::getCanonValue(UChar32 c) const {
  return (int32_t)ucptrie_getucptrie_get_71(fCanonIterData->trie, c);
2655}

2657const UnicodeSet &Normalizer2Impl::getCanonStartSet(int32_t n) const {
  return *(const UnicodeSet *)fCanonIterData->canonStartSets[n];
2659}

2661UBool Normalizer2Impl::isCanonSegmentStarter(UChar32 c) const {
  return getCanonValue(c)>=0;
2663}

2665UBool Normalizer2Impl::getCanonStartSet(UChar32 c, UnicodeSet &set) const {
  int32_t canonValue=getCanonValue(c)&~CANON_NOT_SEGMENT_STARTER0x80000000;
  if(canonValue==0) {
      return FALSE0;
  }
  set.clear();
  int32_t value=canonValue&CANON_VALUE_MASK0x1fffff;
  if((canonValue&CANON_HAS_SET0x200000)!=0) {
      set.addAll(getCanonStartSet(value));
  } else if(value!=0) {
      set.add(value);
  }
  if((canonValue&CANON_HAS_COMPOSITIONS0x40000000)!=0) {
      uint16_t norm16=getRawNorm16(c);
      if(norm16==JAMO_L) {
          UChar32 syllable=
              (UChar32)(Hangul::HANGUL_BASE+(c-Hangul::JAMO_L_BASE)*Hangul::JAMO_VT_COUNT);
          set.add(syllable, syllable+Hangul::JAMO_VT_COUNT-1);
      } else {
          addComposites(getCompositionsList(norm16), set);
      }
  }
  return TRUE1;
2688}

2690U_NAMESPACE_END}

2692// Normalizer2 data swapping ----------------------------------------------- ***

2694U_NAMESPACE_USEusing namespace icu_71;

2696U_CAPIextern "C" int32_t U_EXPORT2
2697unorm2_swapunorm2_swap_71(const UDataSwapper *ds,
          const void *inData, int32_t length, void *outData,
          UErrorCode *pErrorCode) {
  const UDataInfo *pInfo;
  int32_t headerSize;

  const uint8_t *inBytes;
  uint8_t *outBytes;

  const int32_t *inIndexes;
  int32_t indexes[Normalizer2Impl::IX_TOTAL_SIZE+1];

  int32_t i, offset, nextOffset, size;

  /* udata_swapDataHeader checks the arguments */
  headerSize=udata_swapDataHeaderudata_swapDataHeader_71(ds, inData, length, outData, pErrorCode);
  if(pErrorCode==NULL__null || U_FAILURE(*pErrorCode)) {
      return 0;
  }

  /* check data format and format version */
  pInfo=(const UDataInfo *)((const char *)inData+4);
  uint8_t formatVersion0=pInfo->formatVersion[0];
  if(!(
      pInfo->dataFormat[0]==0x4e &&   /* dataFormat="Nrm2" */
      pInfo->dataFormat[1]==0x72 &&
      pInfo->dataFormat[2]==0x6d &&
      pInfo->dataFormat[3]==0x32 &&
      (1<=formatVersion0 && formatVersion0<=4)
  )) {
      udata_printErrorudata_printError_71(ds, "unorm2_swap(): data format %02x.%02x.%02x.%02x (format version %02x) is not recognized as Normalizer2 data\n",
                       pInfo->dataFormat[0], pInfo->dataFormat[1],
                       pInfo->dataFormat[2], pInfo->dataFormat[3],
                       pInfo->formatVersion[0]);
      *pErrorCode=U_UNSUPPORTED_ERROR;
      return 0;
  }

  inBytes=(const uint8_t *)inData+headerSize;
  outBytes=(uint8_t *)outData+headerSize;

  inIndexes=(const int32_t *)inBytes;
  int32_t minIndexesLength;
  if(formatVersion0==1) {
      minIndexesLength=Normalizer2Impl::IX_MIN_MAYBE_YES+1;
  } else if(formatVersion0==2) {
      minIndexesLength=Normalizer2Impl::IX_MIN_YES_NO_MAPPINGS_ONLY+1;
  } else {
      minIndexesLength=Normalizer2Impl::IX_MIN_LCCC_CP+1;
  }

  if(length>=0) {
      length-=headerSize;
      if(length<minIndexesLength*4) {
          udata_printErrorudata_printError_71(ds, "unorm2_swap(): too few bytes (%d after header) for Normalizer2 data\n",
                           length);
          *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
          return 0;
      }
  }

  /* read the first few indexes */
  for(i=0; i<UPRV_LENGTHOF(indexes)(int32_t)(sizeof(indexes)/sizeof((indexes)[0])); ++i) {
      indexes[i]=udata_readInt32udata_readInt32_71(ds, inIndexes[i]);
  }

  /* get the total length of the data */
  size=indexes[Normalizer2Impl::IX_TOTAL_SIZE];

  if(length>=0) {
      if(length<size) {
          udata_printErrorudata_printError_71(ds, "unorm2_swap(): too few bytes (%d after header) for all of Normalizer2 data\n",
                           length);
          *pErrorCode=U_INDEX_OUTOFBOUNDS_ERROR;
          return 0;
      }

      /* copy the data for inaccessible bytes */
      if(inBytes!=outBytes) {
          uprv_memcpy(outBytes, inBytes, size)do { clang diagnostic push
 clang diagnostic ignored "-Waddress"

 (void)0; (void)0; clang diagnostic pop
 :: memcpy(outBytes,
 inBytes, size); } while (false);
      }

      offset=0;

      /* swap the int32_t indexes[] */
      nextOffset=indexes[Normalizer2Impl::IX_NORM_TRIE_OFFSET];
      ds->swapArray32(ds, inBytes, nextOffset-offset, outBytes, pErrorCode);
      offset=nextOffset;

      /* swap the trie */
      nextOffset=indexes[Normalizer2Impl::IX_EXTRA_DATA_OFFSET];
      utrie_swapAnyVersionutrie_swapAnyVersion_71(ds, inBytes+offset, nextOffset-offset, outBytes+offset, pErrorCode);
      offset=nextOffset;

      /* swap the uint16_t extraData[] */
      nextOffset=indexes[Normalizer2Impl::IX_SMALL_FCD_OFFSET];
      ds->swapArray16(ds, inBytes+offset, nextOffset-offset, outBytes+offset, pErrorCode);
      offset=nextOffset;

      /* no need to swap the uint8_t smallFCD[] (new in formatVersion 2) */
      nextOffset=indexes[Normalizer2Impl::IX_SMALL_FCD_OFFSET+1];
      offset=nextOffset;

      U_ASSERT(offset==size)(void)0;
  }

  return headerSize+size;
2804}

2806#endif  // !UCONFIG_NO_NORMALIZATION