Don't mangle \n and "

There is nothing special about quotes and newlines from the object
file point of view, only the assembler has to worry about expanding
the \n and \".

This patch then removes the special handling from the Mangler.

llvm-svn: 194667

llvm/lib/MC/MCSymbol.cpp

@@ -68,12 +68,23 @@ void MCSymbol::print(raw_ostream &OS) const {
   // The name for this MCSymbol is required to be a valid target name.  However,
   // some targets support quoting names with funny characters.  If the name
   // contains a funny character, then print it quoted.
-  if (!NameNeedsQuoting(getName())) {
-    OS << getName();
+  StringRef Name = getName();
+  if (!NameNeedsQuoting(Name)) {
+    OS << Name;
     return;
   }
 
-  OS << '"' << getName() << '"';
+  OS << '"';
+  for (unsigned I = 0, E = Name.size(); I != E; ++I) {
+    char C = Name[I];
+    if (C == '\n')
+      OS << "\\n";
+    else if (C == '"')
+      OS << "\\\"";
+    else
+      OS << C;
+  }
+  OS << '"';
 }
 
 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)

llvm/lib/Target/Mangler.cpp

@@ -23,31 +23,6 @@
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 
-static char HexDigit(int V) {
-  return V < 10 ? V+'0' : V+'A'-10;
-}
-
-static void MangleLetter(SmallVectorImpl<char> &OutName, unsigned char C) {
-  OutName.push_back('_');
-  OutName.push_back(HexDigit(C >> 4));
-  OutName.push_back(HexDigit(C & 15));
-  OutName.push_back('_');
-}
-
-/// appendMangledQuotedName - On systems that support quoted symbols, we still
-/// have to escape some (obscure) characters like " and \n which would break the
-/// assembler's lexing.
-static void appendMangledQuotedName(SmallVectorImpl<char> &OutName,
-                                   StringRef Str) {
-  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
-    if (Str[i] == '"' || Str[i] == '\n')
-      MangleLetter(OutName, Str[i]);
-    else
-      OutName.push_back(Str[i]);
-  }
-}
-
-
 /// getNameWithPrefix - Fill OutName with the name of the appropriate prefix
 /// and the specified name as the global variable name.  GVName must not be
 /// empty.
@@ -85,16 +60,7 @@ void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
   }
 
   // If this is a simple string that doesn't need escaping, just append it.
-  // Quotes can be used unless the string contains a quote or newline.
-  if (Name.find_first_of("\n\"") == StringRef::npos) {
-    OutName.append(Name.begin(), Name.end());
-    return;
-  }
-
-  // Okay, the system allows quoted strings.  We can quote most anything, the
-  // only characters that need escaping are " and \n.
-  assert(Name.find_first_of("\n\"") != StringRef::npos);
-  return appendMangledQuotedName(OutName, Name);
+  OutName.append(Name.begin(), Name.end());
 }
 
 /// AddFastCallStdCallSuffix - Microsoft fastcall and stdcall functions require

llvm/test/CodeGen/X86/newline-and-quote.ll

@@ -0,0 +1,6 @@
+; RUN: llc < %s -mtriple=x86_64-pc-linux-gnu | FileCheck %s
+@"foo\22bar" = global i32 42
+; CHECK: .globl "foo\"bar"
+
+@"foo\0abar" = global i32 42
+; CHECK: .globl "foo\nbar"