[llvm-commits] [llvm-gcc-4.2] r59991 - in /llvm-gcc-4.2/trunk/gcc: config/darwin.h llvm-backend.cpp

[Bill Wendling]

Author: void
Date: Mon Nov 24 17:21:13 2008
New Revision: 59991

URL: http://llvm.org/viewvc/llvm-project?rev=59991&view=rev
Log:
When a constant CFString is created, it's not given a name. LLVM gladly accepts
this and assigns it the name "_unnamed_#_#". This plays havoc with the runtime
because the runtime is expecting the name to be internal. It also prevents the
linker from coalescing these strings. The fix to generate a name for a variable
going into the _cfstring section if it doesn't already have one and it has
internal linkage.

Modified:
    llvm-gcc-4.2/trunk/gcc/config/darwin.h
    llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp

Modified: llvm-gcc-4.2/trunk/gcc/config/darwin.h
URL: http://llvm.org/viewvc/llvm-project/llvm-gcc-4.2/trunk/gcc/config/darwin.h?rev=59991&r1=59990&r2=59991&view=diff

==============================================================================
--- llvm-gcc-4.2/trunk/gcc/config/darwin.h (original)
+++ llvm-gcc-4.2/trunk/gcc/config/darwin.h Mon Nov 24 17:21:13 2008
@@ -694,6 +694,21 @@
       (FN)->setLinkage(Function::ExternalLinkage);                      \
     }                                                                   \
   } while (0)
+
+/* A const CFString is created as an anonymous global variable. LLVM then gives
+   it the name '__unnamed_#_#'. This causes troubles with the runtime, which
+   expects the name to be internal. Give it an internal name here.  */
+#define TARGET_ADJUST_CFSTRING_NAME(GV, SEC)                            \
+  do {                                                                  \
+    if (strcmp((SEC), "__DATA, __cfstring") == 0) {                     \
+      static unsigned i = 0;                                            \
+      const char *fmt = "\01L_unnamed_cfstring_%d";                     \
+      char *N = (char *)alloca(strlen(fmt) + 37);                       \
+      sprintf(N, fmt, i++);                                             \
+      GV->setName(N);                                                   \
+    }                                                                   \
+  } while (0)
+
 #endif
 /* LLVM LOCAL end */
 

Modified: llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp?rev=59991&r1=59990&r2=59991&view=diff

==============================================================================
--- llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp (original)
+++ llvm-gcc-4.2/trunk/gcc/llvm-backend.cpp Mon Nov 24 17:21:13 2008
@@ -1133,6 +1133,11 @@
     if (const char *Section = 
         LLVM_IMPLICIT_TARGET_GLOBAL_VAR_SECTION(decl)) {
       GV->setSection(Section);
+
+#ifdef TARGET_ADJUST_CFSTRING_NAME
+      if (!GV->hasName() && GV->hasInternalLinkage())
+        TARGET_ADJUST_CFSTRING_NAME(GV, Section);
+#endif
     }
 #endif
   }