Imported Upstream version 5.18.0.234

Former-commit-id: 8071ec1a8c5eaa9be24b41745add19297608001f

external/llvm/lib/Support/Regex.cpp

@@ -1,205 +0,0 @@
-//===-- Regex.cpp - Regular Expression matcher implementation -------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements a POSIX regular expression matcher.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/Regex.h"
-#include "regex_impl.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/ADT/StringRef.h"
-#include "llvm/ADT/Twine.h"
-#include <string>
-using namespace llvm;
-
-Regex::Regex() : preg(nullptr), error(REG_BADPAT) {}
-
-Regex::Regex(StringRef regex, unsigned Flags) {
-  unsigned flags = 0;
-  preg = new llvm_regex();
-  preg->re_endp = regex.end();
-  if (Flags & IgnoreCase) 
-    flags |= REG_ICASE;
-  if (Flags & Newline)
-    flags |= REG_NEWLINE;
-  if (!(Flags & BasicRegex))
-    flags |= REG_EXTENDED;
-  error = llvm_regcomp(preg, regex.data(), flags|REG_PEND);
-}
-
-Regex::Regex(Regex &&regex) {
-  preg = regex.preg;
-  error = regex.error;
-  regex.preg = nullptr;
-  regex.error = REG_BADPAT;
-}
-
-Regex::~Regex() {
-  if (preg) {
-    llvm_regfree(preg);
-    delete preg;
-  }
-}
-
-bool Regex::isValid(std::string &Error) const {
-  if (!error)
-    return true;
-  
-  size_t len = llvm_regerror(error, preg, nullptr, 0);
-  
-  Error.resize(len - 1);
-  llvm_regerror(error, preg, &Error[0], len);
-  return false;
-}
-
-/// getNumMatches - In a valid regex, return the number of parenthesized
-/// matches it contains.
-unsigned Regex::getNumMatches() const {
-  return preg->re_nsub;
-}
-
-bool Regex::match(StringRef String, SmallVectorImpl<StringRef> *Matches){
-  if (error)
-    return false;
-
-  unsigned nmatch = Matches ? preg->re_nsub+1 : 0;
-
-  // pmatch needs to have at least one element.
-  SmallVector<llvm_regmatch_t, 8> pm;
-  pm.resize(nmatch > 0 ? nmatch : 1);
-  pm[0].rm_so = 0;
-  pm[0].rm_eo = String.size();
-
-  int rc = llvm_regexec(preg, String.data(), nmatch, pm.data(), REG_STARTEND);
-
-  if (rc == REG_NOMATCH)
-    return false;
-  if (rc != 0) {
-    // regexec can fail due to invalid pattern or running out of memory.
-    error = rc;
-    return false;
-  }
-
-  // There was a match.
-
-  if (Matches) { // match position requested
-    Matches->clear();
-    
-    for (unsigned i = 0; i != nmatch; ++i) {
-      if (pm[i].rm_so == -1) {
-        // this group didn't match
-        Matches->push_back(StringRef());
-        continue;
-      }
-      assert(pm[i].rm_eo >= pm[i].rm_so);
-      Matches->push_back(StringRef(String.data()+pm[i].rm_so,
-                                   pm[i].rm_eo-pm[i].rm_so));
-    }
-  }
-
-  return true;
-}
-
-std::string Regex::sub(StringRef Repl, StringRef String,
-                       std::string *Error) {
-  SmallVector<StringRef, 8> Matches;
-
-  // Reset error, if given.
-  if (Error && !Error->empty()) *Error = "";
-
-  // Return the input if there was no match.
-  if (!match(String, &Matches))
-    return String;
-
-  // Otherwise splice in the replacement string, starting with the prefix before
-  // the match.
-  std::string Res(String.begin(), Matches[0].begin());
-
-  // Then the replacement string, honoring possible substitutions.
-  while (!Repl.empty()) {
-    // Skip to the next escape.
-    std::pair<StringRef, StringRef> Split = Repl.split('\\');
-
-    // Add the skipped substring.
-    Res += Split.first;
-
-    // Check for terminimation and trailing backslash.
-    if (Split.second.empty()) {
-      if (Repl.size() != Split.first.size() &&
-          Error && Error->empty())
-        *Error = "replacement string contained trailing backslash";
-      break;
-    }
-
-    // Otherwise update the replacement string and interpret escapes.
-    Repl = Split.second;
-
-    // FIXME: We should have a StringExtras function for mapping C99 escapes.
-    switch (Repl[0]) {
-      // Treat all unrecognized characters as self-quoting.
-    default:
-      Res += Repl[0];
-      Repl = Repl.substr(1);
-      break;
-
-      // Single character escapes.
-    case 't':
-      Res += '\t';
-      Repl = Repl.substr(1);
-      break;
-    case 'n':
-      Res += '\n';
-      Repl = Repl.substr(1);
-      break;
-
-      // Decimal escapes are backreferences.
-    case '0': case '1': case '2': case '3': case '4':
-    case '5': case '6': case '7': case '8': case '9': {
-      // Extract the backreference number.
-      StringRef Ref = Repl.slice(0, Repl.find_first_not_of("0123456789"));
-      Repl = Repl.substr(Ref.size());
-
-      unsigned RefValue;
-      if (!Ref.getAsInteger(10, RefValue) &&
-          RefValue < Matches.size())
-        Res += Matches[RefValue];
-      else if (Error && Error->empty())
-        *Error = ("invalid backreference string '" + Twine(Ref) + "'").str();
-      break;
-    }
-    }
-  }
-
-  // And finally the suffix.
-  Res += StringRef(Matches[0].end(), String.end() - Matches[0].end());
-
-  return Res;
-}
-
-// These are the special characters matched in functions like "p_ere_exp".
-static const char RegexMetachars[] = "()^$|*+?.[]\\{}";
-
-bool Regex::isLiteralERE(StringRef Str) {
-  // Check for regex metacharacters.  This list was derived from our regex
-  // implementation in regcomp.c and double checked against the POSIX extended
-  // regular expression specification.
-  return Str.find_first_of(RegexMetachars) == StringRef::npos;
-}
-
-std::string Regex::escape(StringRef String) {
-  std::string RegexStr;
-  for (unsigned i = 0, e = String.size(); i != e; ++i) {
-    if (strchr(RegexMetachars, String[i]))
-      RegexStr += '\\';
-    RegexStr += String[i];
-  }
-
-  return RegexStr;
-}