IR: Give function GlobalValue::getRealLinkageName() a less misleading name: dropLLVMManglingEscape().

This function gives the wrong answer on some non-ELF platforms in some
cases. The function that does the right thing lives in Mangler.h. To try to
discourage people from using this function, give it a different name.

Differential Revision: https://reviews.llvm.org/D33162

llvm-svn: 303134
diff --git a/llvm/lib/Analysis/TargetLibraryInfo.cpp b/llvm/lib/Analysis/TargetLibraryInfo.cpp
index 5f05e80..3cf1bbc 100644
--- a/llvm/lib/Analysis/TargetLibraryInfo.cpp
+++ b/llvm/lib/Analysis/TargetLibraryInfo.cpp
@@ -540,7 +540,7 @@
 
   // Check for \01 prefix that is used to mangle __asm declarations and
   // strip it if present.
-  return GlobalValue::getRealLinkageName(funcName);
+  return GlobalValue::dropLLVMManglingEscape(funcName);
 }
 
 bool TargetLibraryInfoImpl::getLibFunc(StringRef funcName,