From: Evan Cheng <evan.cheng@apple.com>
Date: Fri, 6 Feb 2009 17:01:33 +0000 (+0000)
Subject: Document the meaning of -1 for getCopyCost.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=6f8d762e6bad72b2ab9ff710cca3abb0a658fdf0;p=oota-llvm.git

Document the meaning of -1 for getCopyCost.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63933 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/llvm/Target/TargetRegisterInfo.h b/include/llvm/Target/TargetRegisterInfo.h
index 54fc00dd84c..3b452573fc0 100644
--- a/include/llvm/Target/TargetRegisterInfo.h
+++ b/include/llvm/Target/TargetRegisterInfo.h
@@ -202,7 +202,8 @@ public:
   unsigned getAlignment() const { return Alignment; }
 
   /// getCopyCost - Return the cost of copying a value between two registers in
-  /// this class.
+  /// this class. -1 means the register class is very expensive to copy e.g.
+  /// status flag register classes.
   int getCopyCost() const { return CopyCost; }
 };