[AST/etc] Mark {getSourceRange(),getStartLoc(),getEndLoc()} as LLVM_READONLY.

 - The theory here is that we have these functions sprinkled in all over the
   place. This should allow the optimizer to at least realize it can still do
   load CSE across these calls.
 - I blindly marked all instances as such, even though the optimizer can infer
   this attribute in some instances (some of the inline ones) as that was easier
   and also, when given the choice between thinking and not thinking, I prefer
   the latter.

You might think this is mere frivolity, but actually this is good for a .7 -
1.1% speedup on 403.gcc/combine.c, JSC/Interpreter.cpp,
OGF/NSBezierPath-OAExtensions.m.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@152426 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 1 deletions

diff --git a/include/clang/AST/DeclFriend.h b/include/clang/AST/DeclFriend.h
index d8fd646dcd..ba1eb8d729 100644
--- a/include/clang/AST/DeclFriend.h
+++ b/include/clang/AST/DeclFriend.h
@@ -16,6 +16,7 @@
 #define LLVM_CLANG_AST_DECLFRIEND_H
 
 #include "clang/AST/DeclCXX.h"
+#include "llvm/Support/Compiler.h"
 
 namespace clang {
 
@@ -100,7 +101,7 @@ public:
   }
 
   /// Retrieves the source range for the friend declaration.
-  SourceRange getSourceRange() const {
+  SourceRange getSourceRange() const LLVM_READONLY {
     /* FIXME: consider the case of templates wrt start of range. */
     if (NamedDecl *ND = getFriendDecl())
       return SourceRange(getFriendLoc(), ND->getLocEnd());