to more accurately describe what it does. Expand its doxygen comment
to describe what the backedge-taken count is and how it differs
from the actual iteration count of the loop. Adjust names and
comments in associated code accordingly.

llvm-svn: 65382

llvm-svn: 65359

so that ScalarEvolution doesn't hang onto a dangling Loop*, which
could be a problem if another Loop happens to get allocated at the
same address.

llvm-svn: 65323

LoopPass*.
 - Although less precise, this means they can be used in clients
   without RTTI (who would otherwise need to include LoopPass.h, which
   eventually includes things using dynamic_cast). This was the
   simplest solution that presented itself, but I am happy to use a
   better one if available.

llvm-svn: 58010

llvm-svn: 55779

llvm-svn: 52651

llvm-svn: 51666

Also, use SCEV to determine the trip count of the loop, which is more powerful
and accurate that Loop::getTripCount.

llvm-svn: 51179

several things that were neither in an anonymous namespace nor static
but not intended to be global.

llvm-svn: 51017

Patch by Matthijs Kooijman!

llvm-svn: 50861

We need to update PHIs containing the exiting block, not the exit block.  We really should come up with better names for these.

llvm-svn: 50770

llvm-svn: 50473

of this was suggested by Chris.

llvm-svn: 50441

llvm-svn: 50437

llvm-svn: 50436

llvm-svn: 50406

llvm-svn: 50384

llvm-svn: 50383

the trip count.

llvm-svn: 50382