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llvm-6502/test/Transforms/LoopReroll
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James Molloy caba7561ae [LoopReroll] Introduce the concept of DAGRootSets. 
A DAGRootSet models an induction variable being used in a rerollable
loop. For example:

   x[i*3+0] = y1
   x[i*3+1] = y2
   x[i*3+2] = y3

   Base instruction -> i*3
                    +---+----+
                   /    |     \
               ST[y1]  +1     +2  <-- Roots
                        |      |
                      ST[y2] ST[y3]

There may be multiple DAGRootSets, for example:

   x[i*2+0] = ...   (1)
   x[i*2+1] = ...   (1)
   x[i*2+4] = ...   (2)
   x[i*2+5] = ...   (2)
   x[(i+1234)*2+5678] = ... (3)
   x[(i+1234)*2+5679] = ... (3)

This concept is similar to the "Scale" member used previously, but allows
multiple independent sets of roots based off the same induction variable.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@228821 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-11 09:19:47 +00:00
..
basic.ll [LoopReroll] Introduce the concept of DAGRootSets. 2015-02-11 09:19:47 +00:00
nonconst_lb.ll
reduction.ll