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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@27076 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/README.txt b/lib/Target/README.txt
index c2635dade4181062bd96f3476b220837dbc71afd..be390961d7cb5346291e5749145fd548e4b5d107 100644 (file)
--- a/lib/Target/README.txt
+++ b/lib/Target/README.txt
@@ -138,3 +138,15 @@ And teach the dag combiner enough to simplify the code expanded before
 legalize.  It seems plausible that this knowledge would let it simplify other
 stuff too.
 
+//===---------------------------------------------------------------------===//
+
+The loop unroller should be enhanced to be able to unroll loops that aren't 
+single basic blocks.  It should be able to handle stuff like this:
+
+  for (i = 0; i < c1; ++i)
+     if (c2 & (1 << i))
+       foo
+
+where c1/c2 are constants.
+
+