[llvm-commits] [llvm] r72424 - /llvm/trunk/lib/Analysis/ScalarEvolution.cpp

[Dan Gohman]

Author: djg
Date: Tue May 26 12:44:05 2009
New Revision: 72424

URL: http://llvm.org/viewvc/llvm-project?rev=72424&view=rev
Log:
For the return type of SCEVUDivExpr, use the RHS' type instead of
that of the LHS. It doesn't matter for correctness, but the LHS
is more likely than the RHS to be a pointer type in exotic cases,
and it's more tidy to have it return the integer type.

Modified:
    llvm/trunk/lib/Analysis/ScalarEvolution.cpp

Modified: llvm/trunk/lib/Analysis/ScalarEvolution.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/ScalarEvolution.cpp?rev=72424&r1=72423&r2=72424&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/ScalarEvolution.cpp (original)
+++ llvm/trunk/lib/Analysis/ScalarEvolution.cpp Tue May 26 12:44:05 2009
@@ -346,7 +346,12 @@
 }
 
 const Type *SCEVUDivExpr::getType() const {
-  return LHS->getType();
+  // In most cases the types of LHS and RHS will be the same, but in some
+  // crazy cases one or the other may be a pointer. ScalarEvolution doesn't
+  // depend on the type for correctness, but handling types carefully can
+  // avoid extra casts in the SCEVExpander. The LHS is more likely to be
+  // a pointer type than the RHS, so use the RHS' type here.
+  return RHS->getType();
 }
 
 // SCEVAddRecExprs - Only allow the creation of one SCEVAddRecExpr for any