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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10617 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Analysis/BasicAliasAnalysis.cpp b/lib/Analysis/BasicAliasAnalysis.cpp
index 86c27d3e6cce2045cd9e492014e6df8b8b139dd4..8251bb05d22bfd7b2f10ba4853b3cea34ba4d575 100644 (file)
--- a/lib/Analysis/BasicAliasAnalysis.cpp
+++ b/lib/Analysis/BasicAliasAnalysis.cpp
@@ -11,6 +11,11 @@
 // that simply implements a few identities (two different globals cannot alias,
 // etc), but otherwise does no analysis.
 //
+// FIXME: This could be extended for a very simple form of mod/ref information.
+// If a pointer is locally allocated (either malloc or alloca) and never passed
+// into a call or stored to memory, then we know that calls will not mod/ref the
+// memory.  This can be important for tailcallelim.
+//
 //===----------------------------------------------------------------------===//
 
 #include "llvm/Analysis/AliasAnalysis.h"