1 files changed, 231 insertions, 0 deletions
diff --git a/llvm/lib/Support/SpecialCaseList.cpp b/llvm/lib/Support/SpecialCaseList.cpp
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+++ b/llvm/lib/Support/SpecialCaseList.cpp
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+//===-- SpecialCaseList.cpp - special case list for sanitizers ------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This is a utility class for instrumentation passes (like AddressSanitizer
+// or ThreadSanitizer) to avoid instrumenting some functions or global
+// variables, or to instrument some functions or global variables in a specific
+// way, based on a user-supplied list.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/SpecialCaseList.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/Regex.h"
+#include <string>
+#include <system_error>
+#include <utility>
+
+#include <stdio.h>
+namespace llvm {
+
+bool SpecialCaseList::Matcher::insert(std::string Regexp,
+                                      unsigned LineNumber,
+                                      std::string &REError) {
+  if (Regexp.empty()) {
+    REError = "Supplied regexp was blank";
+    return false;
+  }
+
+  if (Regex::isLiteralERE(Regexp)) {
+    Strings[Regexp] = LineNumber;
+    return true;
+  }
+  Trigrams.insert(Regexp);
+
+  // Replace * with .*
+  for (size_t pos = 0; (pos = Regexp.find('*', pos)) != std::string::npos;
+       pos += strlen(".*")) {
+    Regexp.replace(pos, strlen("*"), ".*");
+  }
+
+  Regexp = (Twine("^(") + StringRef(Regexp) + ")$").str();
+
+  // Check that the regexp is valid.
+  Regex CheckRE(Regexp);
+  if (!CheckRE.isValid(REError))
+    return false;
+
+  RegExes.emplace_back(
+      std::make_pair(std::make_unique<Regex>(std::move(CheckRE)), LineNumber));
+  return true;
+}
+
+unsigned SpecialCaseList::Matcher::match(StringRef Query) const {
+  auto It = Strings.find(Query);
+  if (It != Strings.end())
+    return It->second;
+  if (Trigrams.isDefinitelyOut(Query))
+    return false;
+  for (auto& RegExKV : RegExes)
+    if (RegExKV.first->match(Query))
+      return RegExKV.second;
+  return 0;
+}
+
+std::unique_ptr<SpecialCaseList>
+SpecialCaseList::create(const std::vector<std::string> &Paths,
+                        std::string &Error) {
+  std::unique_ptr<SpecialCaseList> SCL(new SpecialCaseList());
+  if (SCL->createInternal(Paths, Error))
+    return SCL;
+  return nullptr;
+}
+
+std::unique_ptr<SpecialCaseList> SpecialCaseList::create(const MemoryBuffer *MB,
+                                                         std::string &Error) {
+  std::unique_ptr<SpecialCaseList> SCL(new SpecialCaseList());
+  if (SCL->createInternal(MB, Error))
+    return SCL;
+  return nullptr;
+}
+
+std::unique_ptr<SpecialCaseList>
+SpecialCaseList::createOrDie(const std::vector<std::string> &Paths) {
+  std::string Error;
+  if (auto SCL = create(Paths, Error))
+    return SCL;
+  report_fatal_error(Error);
+}
+
+bool SpecialCaseList::createInternal(const std::vector<std::string> &Paths,
+                                     std::string &Error) {
+  StringMap<size_t> Sections;
+  for (const auto &Path : Paths) {
+    ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
+        MemoryBuffer::getFile(Path);
+    if (std::error_code EC = FileOrErr.getError()) {
+      Error = (Twine("can't open file '") + Path + "': " + EC.message()).str();
+      return false;
+    }
+    std::string ParseError;
+    if (!parse(FileOrErr.get().get(), Sections, ParseError)) {
+      Error = (Twine("error parsing file '") + Path + "': " + ParseError).str();
+      return false;
+    }
+  }
+  return true;
+}
+
+bool SpecialCaseList::createInternal(const MemoryBuffer *MB,
+                                     std::string &Error) {
+  StringMap<size_t> Sections;
+  if (!parse(MB, Sections, Error))
+    return false;
+  return true;
+}
+
+bool SpecialCaseList::parse(const MemoryBuffer *MB,
+                            StringMap<size_t> &SectionsMap,
+                            std::string &Error) {
+  // Iterate through each line in the blacklist file.
+  SmallVector<StringRef, 16> Lines;
+  MB->getBuffer().split(Lines, '\n');
+
+  unsigned LineNo = 1;
+  StringRef Section = "*";
+
+  for (auto I = Lines.begin(), E = Lines.end(); I != E; ++I, ++LineNo) {
+    *I = I->trim();
+    // Ignore empty lines and lines starting with "#"
+    if (I->empty() || I->startswith("#"))
+      continue;
+
+    // Save section names
+    if (I->startswith("[")) {
+      if (!I->endswith("]")) {
+        Error = (Twine("malformed section header on line ") + Twine(LineNo) +
+                 ": " + *I).str();
+        return false;
+      }
+
+      Section = I->slice(1, I->size() - 1);
+
+      std::string REError;
+      Regex CheckRE(Section);
+      if (!CheckRE.isValid(REError)) {
+        Error =
+            (Twine("malformed regex for section ") + Section + ": '" + REError)
+                .str();
+        return false;
+      }
+
+      continue;
+    }
+
+    // Get our prefix and unparsed regexp.
+    std::pair<StringRef, StringRef> SplitLine = I->split(":");
+    StringRef Prefix = SplitLine.first;
+    if (SplitLine.second.empty()) {
+      // Missing ':' in the line.
+      Error = (Twine("malformed line ") + Twine(LineNo) + ": '" +
+               SplitLine.first + "'").str();
+      return false;
+    }
+
+    std::pair<StringRef, StringRef> SplitRegexp = SplitLine.second.split("=");
+    std::string Regexp = SplitRegexp.first;
+    StringRef Category = SplitRegexp.second;
+
+    // Create this section if it has not been seen before.
+    if (SectionsMap.find(Section) == SectionsMap.end()) {
+      std::unique_ptr<Matcher> M = std::make_unique<Matcher>();
+      std::string REError;
+      if (!M->insert(Section, LineNo, REError)) {
+        Error = (Twine("malformed section ") + Section + ": '" + REError).str();
+        return false;
+      }
+
+      SectionsMap[Section] = Sections.size();
+      Sections.emplace_back(std::move(M));
+    }
+
+    auto &Entry = Sections[SectionsMap[Section]].Entries[Prefix][Category];
+    std::string REError;
+    if (!Entry.insert(std::move(Regexp), LineNo, REError)) {
+      Error = (Twine("malformed regex in line ") + Twine(LineNo) + ": '" +
+               SplitLine.second + "': " + REError).str();
+      return false;
+    }
+  }
+  return true;
+}
+
+SpecialCaseList::~SpecialCaseList() {}
+
+bool SpecialCaseList::inSection(StringRef Section, StringRef Prefix,
+                                StringRef Query, StringRef Category) const {
+  return inSectionBlame(Section, Prefix, Query, Category);
+}
+
+unsigned SpecialCaseList::inSectionBlame(StringRef Section, StringRef Prefix,
+                                         StringRef Query,
+                                         StringRef Category) const {
+  for (auto &SectionIter : Sections)
+    if (SectionIter.SectionMatcher->match(Section)) {
+      unsigned Blame =
+          inSectionBlame(SectionIter.Entries, Prefix, Query, Category);
+      if (Blame)
+        return Blame;
+    }
+  return 0;
+}
+
+unsigned SpecialCaseList::inSectionBlame(const SectionEntries &Entries,
+                                         StringRef Prefix, StringRef Query,
+                                         StringRef Category) const {
+  SectionEntries::const_iterator I = Entries.find(Prefix);
+  if (I == Entries.end()) return 0;
+  StringMap<Matcher>::const_iterator II = I->second.find(Category);
+  if (II == I->second.end()) return 0;
+
+  return II->getValue().match(Query);
+}
+
+}  // namespace llvm