[llvm-commits] [dragonegg] r137937 - /dragonegg/trunk/src/Backend.cpp

[Duncan Sands]

Author: baldrick
Date: Thu Aug 18 06:48:30 2011
New Revision: 137937

URL: http://llvm.org/viewvc/llvm-project?rev=137937&view=rev
Log:
Mark constant globals "unnamed_addr", enabing constant merging, when doing
so is clearly safe.

Modified:
    dragonegg/trunk/src/Backend.cpp

Modified: dragonegg/trunk/src/Backend.cpp
URL: http://llvm.org/viewvc/llvm-project/dragonegg/trunk/src/Backend.cpp?rev=137937&r1=137936&r2=137937&view=diff
==============================================================================
--- dragonegg/trunk/src/Backend.cpp (original)
+++ dragonegg/trunk/src/Backend.cpp Thu Aug 18 06:48:30 2011
@@ -886,6 +886,14 @@
   TARGET_ADJUST_LLVM_LINKAGE(GV, decl);
 #endif /* TARGET_ADJUST_LLVM_LINKAGE */
 
+  // If this is a constant that never has its address taken then allow it to be
+  // merged with other constants (C and C++ say that different variables should
+  // have different addresses, which is why this is only correct if the address
+  // is not taken).  However if -fmerge-all-constants was specified then allow
+  // merging even if the address was taken.
+  GV->setUnnamedAddr(GV->isConstant() && (flag_merge_constants >= 2 ||
+                                          !TREE_ADDRESSABLE(decl)));
+
   handleVisibility(decl, GV);
 
   // Set the section for the global.