Decouple llvm::SpecialCaseList text representation and its LLVM IR semantics.

Turn llvm::SpecialCaseList into a simple class that parses text files in
a specified format and knows nothing about LLVM IR. Move this class into
LLVMSupport library. Implement two users of this class:
  * DFSanABIList in DFSan instrumentation pass.
  * SanitizerBlacklist in Clang CodeGen library.
The latter will be modified to use actual source-level information from frontend
(source file names) instead of unstable LLVM IR things (LLVM Module identifier).

Remove dependency edge from ClangCodeGen/ClangDriver to LLVMTransformUtils.

No functionality change.

llvm-svn: 212643
diff --git a/clang/lib/CodeGen/SanitizerBlacklist.cpp b/clang/lib/CodeGen/SanitizerBlacklist.cpp
new file mode 100644
index 0000000..60bdbe1
--- /dev/null
+++ b/clang/lib/CodeGen/SanitizerBlacklist.cpp
@@ -0,0 +1,48 @@
+//===--- SanitizerBlacklist.cpp - Blacklist for sanitizers ----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// User-provided blacklist used to disable/alter instrumentation done in
+// sanitizers.
+//
+//===----------------------------------------------------------------------===//
+#include "SanitizerBlacklist.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GlobalValue.h"
+#include "llvm/IR/Module.h"
+
+using namespace clang;
+using namespace CodeGen;
+
+static StringRef GetGlobalTypeString(const llvm::GlobalValue &G) {
+  // Types of GlobalVariables are always pointer types.
+  llvm::Type *GType = G.getType()->getElementType();
+  // For now we support blacklisting struct types only.
+  if (llvm::StructType *SGType = dyn_cast<llvm::StructType>(GType)) {
+    if (!SGType->isLiteral())
+      return SGType->getName();
+  }
+  return "<unknown type>";
+}
+
+bool SanitizerBlacklist::isIn(const llvm::Module &M,
+                              const StringRef Category) const {
+  return SCL->inSection("src", M.getModuleIdentifier(), Category);
+}
+
+bool SanitizerBlacklist::isIn(const llvm::Function &F) const {
+  return isIn(*F.getParent()) ||
+         SCL->inSection("fun", F.getName(), "");
+}
+
+bool SanitizerBlacklist::isIn(const llvm::GlobalVariable &G,
+                              const StringRef Category) const {
+  return isIn(*G.getParent(), Category) ||
+         SCL->inSection("global", G.getName(), Category) ||
+         SCL->inSection("type", GetGlobalTypeString(G), Category);
+}