[llvm-commits] [llvm] r159082 - /llvm/trunk/lib/Target/README.txt

[Benjamin Kramer]

Author: d0k
Date: Sat Jun 23 10:19:31 2012
New Revision: 159082

URL: http://llvm.org/viewvc/llvm-project?rev=159082&view=rev
Log:
Add a microoptimization note.

Modified:
    llvm/trunk/lib/Target/README.txt

Modified: llvm/trunk/lib/Target/README.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/README.txt?rev=159082&r1=159081&r2=159082&view=diff
==============================================================================
--- llvm/trunk/lib/Target/README.txt (original)
+++ llvm/trunk/lib/Target/README.txt Sat Jun 23 10:19:31 2012
@@ -964,6 +964,12 @@
 
 //===---------------------------------------------------------------------===//
 
+unsigned f(unsigned x) { return ((x & 7) + 1) & 15; }
+The & 15 part should be optimized away, it doesn't change the result. Currently
+not optimized with "clang -emit-llvm-bc | opt -std-compile-opts".
+
+//===---------------------------------------------------------------------===//
+
 This was noticed in the entryblock for grokdeclarator in 403.gcc:
 
         %tmp = icmp eq i32 %decl_context, 4