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-rw-r--r--utils/TableGen/StringMatcher.cpp149
1 files changed, 0 insertions, 149 deletions
diff --git a/utils/TableGen/StringMatcher.cpp b/utils/TableGen/StringMatcher.cpp
deleted file mode 100644
index 6aedcbf..0000000
--- a/utils/TableGen/StringMatcher.cpp
+++ /dev/null
@@ -1,149 +0,0 @@
-//===- StringMatcher.cpp - Generate a matcher for input strings -----------===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements the StringMatcher class.
-//
-//===----------------------------------------------------------------------===//
-
-#include "StringMatcher.h"
-#include "llvm/Support/raw_ostream.h"
-#include <map>
-using namespace llvm;
-
-/// FindFirstNonCommonLetter - Find the first character in the keys of the
-/// string pairs that is not shared across the whole set of strings. All
-/// strings are assumed to have the same length.
-static unsigned
-FindFirstNonCommonLetter(const std::vector<const
- StringMatcher::StringPair*> &Matches) {
- assert(!Matches.empty());
- for (unsigned i = 0, e = Matches[0]->first.size(); i != e; ++i) {
- // Check to see if letter i is the same across the set.
- char Letter = Matches[0]->first[i];
-
- for (unsigned str = 0, e = Matches.size(); str != e; ++str)
- if (Matches[str]->first[i] != Letter)
- return i;
- }
-
- return Matches[0]->first.size();
-}
-
-/// EmitStringMatcherForChar - Given a set of strings that are known to be the
-/// same length and whose characters leading up to CharNo are the same, emit
-/// code to verify that CharNo and later are the same.
-///
-/// \return - True if control can leave the emitted code fragment.
-bool StringMatcher::
-EmitStringMatcherForChar(const std::vector<const StringPair*> &Matches,
- unsigned CharNo, unsigned IndentCount) const {
- assert(!Matches.empty() && "Must have at least one string to match!");
- std::string Indent(IndentCount*2+4, ' ');
-
- // If we have verified that the entire string matches, we're done: output the
- // matching code.
- if (CharNo == Matches[0]->first.size()) {
- assert(Matches.size() == 1 && "Had duplicate keys to match on");
-
- // If the to-execute code has \n's in it, indent each subsequent line.
- StringRef Code = Matches[0]->second;
-
- std::pair<StringRef, StringRef> Split = Code.split('\n');
- OS << Indent << Split.first << "\t // \"" << Matches[0]->first << "\"\n";
-
- Code = Split.second;
- while (!Code.empty()) {
- Split = Code.split('\n');
- OS << Indent << Split.first << "\n";
- Code = Split.second;
- }
- return false;
- }
-
- // Bucket the matches by the character we are comparing.
- std::map<char, std::vector<const StringPair*> > MatchesByLetter;
-
- for (unsigned i = 0, e = Matches.size(); i != e; ++i)
- MatchesByLetter[Matches[i]->first[CharNo]].push_back(Matches[i]);
-
-
- // If we have exactly one bucket to match, see how many characters are common
- // across the whole set and match all of them at once.
- if (MatchesByLetter.size() == 1) {
- unsigned FirstNonCommonLetter = FindFirstNonCommonLetter(Matches);
- unsigned NumChars = FirstNonCommonLetter-CharNo;
-
- // Emit code to break out if the prefix doesn't match.
- if (NumChars == 1) {
- // Do the comparison with if (Str[1] != 'f')
- // FIXME: Need to escape general characters.
- OS << Indent << "if (" << StrVariableName << "[" << CharNo << "] != '"
- << Matches[0]->first[CharNo] << "')\n";
- OS << Indent << " break;\n";
- } else {
- // Do the comparison with if (Str.substr(1, 3) != "foo").
- // FIXME: Need to escape general strings.
- OS << Indent << "if (" << StrVariableName << ".substr(" << CharNo << ", "
- << NumChars << ") != \"";
- OS << Matches[0]->first.substr(CharNo, NumChars) << "\")\n";
- OS << Indent << " break;\n";
- }
-
- return EmitStringMatcherForChar(Matches, FirstNonCommonLetter, IndentCount);
- }
-
- // Otherwise, we have multiple possible things, emit a switch on the
- // character.
- OS << Indent << "switch (" << StrVariableName << "[" << CharNo << "]) {\n";
- OS << Indent << "default: break;\n";
-
- for (std::map<char, std::vector<const StringPair*> >::iterator LI =
- MatchesByLetter.begin(), E = MatchesByLetter.end(); LI != E; ++LI) {
- // TODO: escape hard stuff (like \n) if we ever care about it.
- OS << Indent << "case '" << LI->first << "':\t // "
- << LI->second.size() << " string";
- if (LI->second.size() != 1) OS << 's';
- OS << " to match.\n";
- if (EmitStringMatcherForChar(LI->second, CharNo+1, IndentCount+1))
- OS << Indent << " break;\n";
- }
-
- OS << Indent << "}\n";
- return true;
-}
-
-
-/// Emit - Top level entry point.
-///
-void StringMatcher::Emit(unsigned Indent) const {
- // If nothing to match, just fall through.
- if (Matches.empty()) return;
-
- // First level categorization: group strings by length.
- std::map<unsigned, std::vector<const StringPair*> > MatchesByLength;
-
- for (unsigned i = 0, e = Matches.size(); i != e; ++i)
- MatchesByLength[Matches[i].first.size()].push_back(&Matches[i]);
-
- // Output a switch statement on length and categorize the elements within each
- // bin.
- OS.indent(Indent*2+2) << "switch (" << StrVariableName << ".size()) {\n";
- OS.indent(Indent*2+2) << "default: break;\n";
-
- for (std::map<unsigned, std::vector<const StringPair*> >::iterator LI =
- MatchesByLength.begin(), E = MatchesByLength.end(); LI != E; ++LI) {
- OS.indent(Indent*2+2) << "case " << LI->first << ":\t // "
- << LI->second.size()
- << " string" << (LI->second.size() == 1 ? "" : "s") << " to match.\n";
- if (EmitStringMatcherForChar(LI->second, 0, Indent))
- OS.indent(Indent*2+4) << "break;\n";
- }
-
- OS.indent(Indent*2+2) << "}\n";
-}