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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49469 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SimpleRegisterCoalescing.h b/lib/CodeGen/SimpleRegisterCoalescing.h
index 7823ba0df4b2110499b93c08587f91f61e37834d..fa63159d1c86b0c4a1cf2d23ac7f1c67458a67b7 100644 (file)
--- a/lib/CodeGen/SimpleRegisterCoalescing.h
+++ b/lib/CodeGen/SimpleRegisterCoalescing.h
@@ -223,6 +223,8 @@ namespace llvm {
     /// subregister.
     void UpdateRegDefsUses(unsigned SrcReg, unsigned DstReg, unsigned SubIdx);
 
+    /// RemoveDeadImpDef - Remove implicit_def instructions which are
+    /// "re-defining" registers due to insert_subreg coalescing. e.g.
     void RemoveDeadImpDef(unsigned Reg, LiveInterval &LI);
 
     /// RemoveUnnecessaryKills - Remove kill markers that are no longer accurate