Goodbye, JSONParser...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154930 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 0 insertions, 303 deletions

diff --git a/lib/Support/CMakeLists.txt b/lib/Support/CMakeLists.txt
index 9b3b6c8..fbbcf78 100644
--- a/lib/Support/CMakeLists.txt
+++ b/lib/Support/CMakeLists.txt
@@ -32,7 +32,6 @@ add_llvm_library(LLVMSupport
   IntrusiveRefCntPtr.cpp
   IsInf.cpp
   IsNAN.cpp
-  JSONParser.cpp
   LockFileManager.cpp
   ManagedStatic.cpp
   MemoryBuffer.cpp
diff --git a/lib/Support/JSONParser.cpp b/lib/Support/JSONParser.cpp
deleted file mode 100644
index 5dfcf29..0000000
--- a/lib/Support/JSONParser.cpp
+++ /dev/null
@@ -1,302 +0,0 @@
-//===--- JSONParser.cpp - Simple JSON parser ------------------------------===//
-//
-//                     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 JSON parser.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Support/JSONParser.h"
-
-#include "llvm/ADT/Twine.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/MemoryBuffer.h"
-
-using namespace llvm;
-
-JSONParser::JSONParser(StringRef Input, SourceMgr *SM)
-  : SM(SM), Failed(false) {
-  InputBuffer = MemoryBuffer::getMemBuffer(Input, "JSON");
-  SM->AddNewSourceBuffer(InputBuffer, SMLoc());
-  End = InputBuffer->getBuffer().end();
-  Position = InputBuffer->getBuffer().begin();
-}
-
-JSONValue *JSONParser::parseRoot() {
-  if (Position != InputBuffer->getBuffer().begin())
-    report_fatal_error("Cannot reuse JSONParser.");
-  if (isWhitespace())
-    nextNonWhitespace();
-  if (errorIfAtEndOfFile("'[' or '{' at start of JSON text"))
-    return 0;
-  switch (*Position) {
-    case '[':
-      return new (ValueAllocator.Allocate<JSONArray>(1)) JSONArray(this);
-    case '{':
-      return new (ValueAllocator.Allocate<JSONObject>(1)) JSONObject(this);
-    default:
-      setExpectedError("'[' or '{' at start of JSON text", *Position);
-      return 0;
-  }
-}
-
-bool JSONParser::validate() {
-  JSONValue *Root = parseRoot();
-  if (Root == NULL) {
-    return false;
-  }
-  return skip(*Root);
-}
-
-bool JSONParser::skip(const JSONAtom &Atom) {
-  switch(Atom.getKind()) {
-    case JSONAtom::JK_Array:
-    case JSONAtom::JK_Object:
-      return skipContainer(*cast<JSONContainer>(&Atom));
-    case JSONAtom::JK_String:
-      return true;
-    case JSONAtom::JK_KeyValuePair:
-      return skip(*cast<JSONKeyValuePair>(&Atom)->Value);
-  }
-  llvm_unreachable("Impossible enum value.");
-}
-
-// Sets the current error to:
-// "expected <Expected>, but found <Found>".
-void JSONParser::setExpectedError(StringRef Expected, StringRef Found) {
-  SM->PrintMessage(SMLoc::getFromPointer(Position), SourceMgr::DK_Error,
-    "expected " + Expected + ", but found " + Found + ".", ArrayRef<SMRange>());
-  Failed = true;
-}
-
-// Sets the current error to:
-// "expected <Expected>, but found <Found>".
-void JSONParser::setExpectedError(StringRef Expected, char Found) {
-  setExpectedError(Expected, ("'" + StringRef(&Found, 1) + "'").str());
-}
-
-// If there is no character available, returns true and sets the current error
-// to: "expected <Expected>, but found EOF.".
-bool JSONParser::errorIfAtEndOfFile(StringRef Expected) {
-  if (Position == End) {
-    setExpectedError(Expected, "EOF");
-    return true;
-  }
-  return false;
-}
-
-// Sets the current error if the current character is not C to:
-// "expected 'C', but got <current character>".
-bool JSONParser::errorIfNotAt(char C, StringRef Message) {
-  if (*Position != C) {
-    std::string Expected =
-      ("'" + StringRef(&C, 1) + "' " + Message).str();
-    if (Position == End)
-      setExpectedError(Expected, "EOF");
-    else
-      setExpectedError(Expected, *Position);
-    return true;
-  }
-  return false;
-}
-
-// Forbidding inlining improves performance by roughly 20%.
-// FIXME: Remove once llvm optimizes this to the faster version without hints.
-LLVM_ATTRIBUTE_NOINLINE static bool
-wasEscaped(StringRef::iterator First, StringRef::iterator Position);
-
-// Returns whether a character at 'Position' was escaped with a leading '\'.
-// 'First' specifies the position of the first character in the string.
-static bool wasEscaped(StringRef::iterator First,
-                       StringRef::iterator Position) {
-  assert(Position - 1 >= First);
-  StringRef::iterator I = Position - 1;
-  // We calulate the number of consecutive '\'s before the current position
-  // by iterating backwards through our string.
-  while (I >= First && *I == '\\') --I;
-  // (Position - 1 - I) now contains the number of '\'s before the current
-  // position. If it is odd, the character at 'Positon' was escaped.
-  return (Position - 1 - I) % 2 == 1;
-}
-
-// Parses a JSONString, assuming that the current position is on a quote.
-JSONString *JSONParser::parseString() {
-  assert(Position != End);
-  assert(!isWhitespace());
-  if (errorIfNotAt('"', "at start of string"))
-    return 0;
-  StringRef::iterator First = Position + 1;
-
-  // Benchmarking shows that this loop is the hot path of the application with
-  // about 2/3rd of the runtime cycles. Since escaped quotes are not the common
-  // case, and multiple escaped backslashes before escaped quotes are very rare,
-  // we pessimize this case to achieve a smaller inner loop in the common case.
-  // We're doing that by having a quick inner loop that just scans for the next
-  // quote. Once we find the quote we check the last character to see whether
-  // the quote might have been escaped. If the last character is not a '\', we
-  // know the quote was not escaped and have thus found the end of the string.
-  // If the immediately preceding character was a '\', we have to scan backwards
-  // to see whether the previous character was actually an escaped backslash, or
-  // an escape character for the quote. If we find that the current quote was
-  // escaped, we continue parsing for the next quote and repeat.
-  // This optimization brings around 30% performance improvements.
-  do {
-    // Step over the current quote.
-    ++Position;
-    // Find the next quote.
-    while (Position != End && *Position != '"')
-      ++Position;
-    if (errorIfAtEndOfFile("'\"' at end of string"))
-      return 0;
-    // Repeat until the previous character was not a '\' or was an escaped
-    // backslash.
-  } while (*(Position - 1) == '\\' && wasEscaped(First, Position));
-
-  return new (ValueAllocator.Allocate<JSONString>())
-      JSONString(StringRef(First, Position - First));
-}
-
-
-// Advances the position to the next non-whitespace position.
-void JSONParser::nextNonWhitespace() {
-  do {
-    ++Position;
-  } while (isWhitespace());
-}
-
-// Checks if there is a whitespace character at the current position.
-bool JSONParser::isWhitespace() {
-  return *Position == ' ' || *Position == '\t' ||
-         *Position == '\n' || *Position == '\r';
-}
-
-bool JSONParser::failed() const {
-  return Failed;
-}
-
-// Parses a JSONValue, assuming that the current position is at the first
-// character of the value.
-JSONValue *JSONParser::parseValue() {
-  assert(Position != End);
-  assert(!isWhitespace());
-  switch (*Position) {
-    case '[':
-      return new (ValueAllocator.Allocate<JSONArray>(1)) JSONArray(this);
-    case '{':
-      return new (ValueAllocator.Allocate<JSONObject>(1)) JSONObject(this);
-    case '"':
-      return parseString();
-    default:
-      setExpectedError("'[', '{' or '\"' at start of value", *Position);
-      return 0;
-  }
-}
-
-// Parses a JSONKeyValuePair, assuming that the current position is at the first
-// character of the key, value pair.
-JSONKeyValuePair *JSONParser::parseKeyValuePair() {
-  assert(Position != End);
-  assert(!isWhitespace());
-
-  JSONString *Key = parseString();
-  if (Key == 0)
-    return 0;
-
-  nextNonWhitespace();
-  if (errorIfNotAt(':', "between key and value"))
-    return 0;
-
-  nextNonWhitespace();
-  const JSONValue *Value = parseValue();
-  if (Value == 0)
-    return 0;
-
-  return new (ValueAllocator.Allocate<JSONKeyValuePair>(1))
-    JSONKeyValuePair(Key, Value);
-}
-
-/// \brief Parses the first element of a JSON array or object, or closes the
-/// array.
-///
-/// The method assumes that the current position is before the first character
-/// of the element, with possible white space in between. When successful, it
-/// returns the new position after parsing the element. Otherwise, if there is
-/// no next value, it returns a default constructed StringRef::iterator.
-StringRef::iterator JSONParser::parseFirstElement(JSONAtom::Kind ContainerKind,
-                                                  char StartChar, char EndChar,
-                                                  const JSONAtom *&Element) {
-  assert(*Position == StartChar);
-  Element = 0;
-  nextNonWhitespace();
-  if (errorIfAtEndOfFile("value or end of container at start of container"))
-    return StringRef::iterator();
-
-  if (*Position == EndChar)
-    return StringRef::iterator();
-
-  Element = parseElement(ContainerKind);
-  if (Element == 0)
-    return StringRef::iterator();
-
-  return Position;
-}
-
-/// \brief Parses the next element of a JSON array or object, or closes the
-/// array.
-///
-/// The method assumes that the current position is before the ',' which
-/// separates the next element from the current element. When successful, it
-/// returns the new position after parsing the element. Otherwise, if there is
-/// no next value, it returns a default constructed StringRef::iterator.
-StringRef::iterator JSONParser::parseNextElement(JSONAtom::Kind ContainerKind,
-                                                 char EndChar,
-                                                 const JSONAtom *&Element) {
-  Element = 0;
-  nextNonWhitespace();
-  if (errorIfAtEndOfFile("',' or end of container for next element"))
-    return 0;
-
-  if (*Position == ',') {
-    nextNonWhitespace();
-    if (errorIfAtEndOfFile("element in container"))
-      return StringRef::iterator();
-
-    Element = parseElement(ContainerKind);
-    if (Element == 0)
-      return StringRef::iterator();
-
-    return Position;
-  } else if (*Position == EndChar) {
-      return StringRef::iterator();
-  } else {
-    setExpectedError("',' or end of container for next element", *Position);
-    return StringRef::iterator();
-  }
-}
-
-const JSONAtom *JSONParser::parseElement(JSONAtom::Kind ContainerKind) {
-  switch (ContainerKind) {
-    case JSONAtom::JK_Array:
-      return parseValue();
-    case JSONAtom::JK_Object:
-      return parseKeyValuePair();
-    default:
-      llvm_unreachable("Impossible code path");
-  }
-}
-
-bool JSONParser::skipContainer(const JSONContainer &Container) {
-  for (JSONContainer::AtomIterator I = Container.atom_current(),
-                                   E = Container.atom_end();
-       I != E; ++I) {
-    assert(*I != 0);
-    if (!skip(**I))
-      return false;
-  }
-  return !failed();
-}