[llvm] 4d18b4a - [SCEV] Add a clarifying comment around ExitLimit construction

[Philip Reames via llvm-commits]

Author: Philip Reames
Date: 2019-10-25T10:33:02-07:00
New Revision: 4d18b4a7c4fd60fc9e4e5e7f1d968f58a5ffff41

URL: https://github.com/llvm/llvm-project/commit/4d18b4a7c4fd60fc9e4e5e7f1d968f58a5ffff41
DIFF: https://github.com/llvm/llvm-project/commit/4d18b4a7c4fd60fc9e4e5e7f1d968f58a5ffff41.diff

LOG: [SCEV] Add a clarifying comment around ExitLimit construction

Added: 
    

Modified: 
    llvm/include/llvm/Analysis/ScalarEvolution.h

Removed: 
    


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diff  --git a/llvm/include/llvm/Analysis/ScalarEvolution.h b/llvm/include/llvm/Analysis/ScalarEvolution.h
index 5cbc40666105..57f84c1d0ebf 100644
--- a/llvm/include/llvm/Analysis/ScalarEvolution.h
+++ b/llvm/include/llvm/Analysis/ScalarEvolution.h
@@ -1213,6 +1213,9 @@ class ScalarEvolution {
       Predicates.insert(P);
     }
 
+    /// Construct either an exact exit limit from a constant, or an unknown
+    /// one from a SCEVCouldNotCompute.  No other types of SCEVs are allowed
+    /// as arguments and asserts enforce that internally.
     /*implicit*/ ExitLimit(const SCEV *E);
 
     ExitLimit(