Allow per-character control over what target assemblers allow in symbol

names.  This also changes the default to allow all of "$_." in addition
to letters and numbers as symbol names.  If you don't want this, use
markCharUnacceptable to remove one of these or markCharAcceptable to add
to the set.  This corresponds with what GAS accepts by default.

Also, this includes some minor speedups


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24293 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 25 insertions, 7 deletions

diff --git a/lib/VMCore/Mangler.cpp b/lib/VMCore/Mangler.cpp
index 418eb9a..44fe100 100644
--- a/lib/VMCore/Mangler.cpp
+++ b/lib/VMCore/Mangler.cpp
@@ -22,7 +22,8 @@ static char HexDigit(int V) {
 }
 
 static std::string MangleLetter(unsigned char C) {
-  return std::string("_")+HexDigit(C >> 4) + HexDigit(C & 15) + "_";
+  char Result[] = { '_', HexDigit(C >> 4), HexDigit(C & 15), '_', 0 };
+  return Result;
 }
 
 /// makeNameProper - We don't want identifier names non-C-identifier characters
@@ -30,6 +31,7 @@ static std::string MangleLetter(unsigned char C) {
 ///
 std::string Mangler::makeNameProper(const std::string &X, const char *Prefix) {
   std::string Result;
+  if (X.empty()) return X;  // Empty names are uniqued by the caller.
   
   if (!UseQuotes) {
     // If X does not start with (char)1, add the prefix.
@@ -39,16 +41,16 @@ std::string Mangler::makeNameProper(const std::string &X, const char *Prefix) {
     else
       ++I;  // Skip over the marker.
     
-    // Mangle the first letter specially, don't allow numbers...
+    // Mangle the first letter specially, don't allow numbers.
     if (*I >= '0' && *I <= '9')
       Result += MangleLetter(*I++);
 
-    for (std::string::const_iterator E = X.end(); I != E; ++I)
-      if ((*I < 'a' || *I > 'z') && (*I < 'A' || *I > 'Z') &&
-          (*I < '0' || *I > '9') && *I != '_' && *I != '$')
+    for (std::string::const_iterator E = X.end(); I != E; ++I) {
+      if (!isCharAcceptable(*I))
         Result += MangleLetter(*I);
       else
         Result += *I;
+    }
   } else {
     bool NeedsQuotes = false;
     
@@ -67,8 +69,7 @@ std::string Mangler::makeNameProper(const std::string &X, const char *Prefix) {
       if (*I == '"')
         Result += "_QQ_";
       else {
-        if ((*I < 'a' || *I > 'z') && (*I < 'A' || *I > 'Z') &&
-            (*I < '0' || *I > '9') && *I != '_' && *I != '$' && *I != '.')
+        if (!isCharAcceptable(*I))
           NeedsQuotes = true;
         Result += *I;
       }
@@ -147,6 +148,23 @@ void Mangler::InsertName(GlobalValue *GV,
 
 Mangler::Mangler(Module &M, const char *prefix)
   : Prefix(prefix), UseQuotes(false), Count(0), TypeCounter(0) {
+  std::fill(AcceptableChars, 
+          AcceptableChars+sizeof(AcceptableChars)/sizeof(AcceptableChars[0]),
+            0);
+
+  // Letters and numbers are acceptable.
+  for (unsigned char X = 'a'; X <= 'z'; ++X)
+    markCharAcceptable(X);
+  for (unsigned char X = 'A'; X <= 'Z'; ++X)
+    markCharAcceptable(X);
+  for (unsigned char X = '0'; X <= '9'; ++X)
+    markCharAcceptable(X);
+  
+  // These chars are acceptable.
+  markCharAcceptable('_');
+  markCharAcceptable('$');
+  markCharAcceptable('.');
+    
   // Calculate which global values have names that will collide when we throw
   // away type information.
   std::map<std::string, GlobalValue*> Names;