An algorithm for incrementally updating LoopInfo within a
LoopPassManager. The incremental update should be extremely cheap in
most cases and can be used in places where it's not feasible to
regenerate the entire loop forest.
- "Unloop" is a node in the loop tree whose last backedge has been removed.
- Perform reverse dataflow on the block inside Unloop to propagate the
nearest loop from the block's successors.
- For reducible CFG, each block in unloop is visited exactly
once. This is because unloop no longer has a backedge and blocks
within subloops don't change parents.
- Immediate subloops are summarized by the nearest loop reachable from
their exits or exits within nested subloops.
- At completion the unloop blocks each have a new parent loop, and
each immediate subloop has a new parent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137276 91177308-0d34-0410-b5e6-96231b3b80d8
data in-register prior to saving to memory. When we reorder the data in memory
we prevent the need to save multiple scalars to memory, making a single regular
store.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137238 91177308-0d34-0410-b5e6-96231b3b80d8
Use an Init (ultimately a StringInit) to represent the Record name.
This allows the name to be composed by standard TableGen operators.
This will enable us to get rid of the ugly #NAME# hack processing and
naturally replace it with operators. It also increases flexibility
and power of the TableGen language by allowing record identifiers to
be computed dynamically.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137232 91177308-0d34-0410-b5e6-96231b3b80d8
Add a method to return an Init as an unquoted string. This primarily
affects StringInit where we return the value without surrounding it
with quotes.
This is in preparation for removing the ugly #NAME# hack and replacing
it with standard TabelGen operators.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137231 91177308-0d34-0410-b5e6-96231b3b80d8
Also, my apologies for spoiling the autocomplete on SimplifyInstructions.cpp. I couldn't think of a better filename.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137229 91177308-0d34-0410-b5e6-96231b3b80d8
def : Pat<(X86Movss VR128:$src1,
(bc_v4i32 (v2i64 (load addr:$src2)))),
(MOVLPSrm VR128:$src1, addr:$src2)>;
This matches a MOVSS dag with a MOVLPS instruction. However, MOVSS will replace only the low 32 bits of the register, while the MOVLPS instruction will replace the low 64 bits. A testcase is added and illustrates the bug and also modified the one that was already present. Patch by Tanya Lattner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137227 91177308-0d34-0410-b5e6-96231b3b80d8
based on ScalarEvolution without changing the induction variable phis.
This utility is the main tool of IndVarSimplifyPass, but the pass also
restructures induction variables in strange ways that are sensitive to
pass ordering. This provides a way for other loop passes to simplify
new uses of induction variables created during transformation. The
utility may be used by any pass that preserves ScalarEvolution. Soon
LoopUnroll will use it.
The net effect in this checkin is to cleanup the IndVarSimplify pass
by factoring out the SimplifyIndVar algorithm into a standalone utility.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137197 91177308-0d34-0410-b5e6-96231b3b80d8
These are not individual bug fixes. I had to rewrite a good chunk of
the unroller to make it sane. I think it was getting lucky on trivial
completely unrolled loops with no early exits. I included some fairly
simple unit tests for partial unrolling. I didn't do much stress
testing, so it may not be perfect, but should be usable now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137190 91177308-0d34-0410-b5e6-96231b3b80d8
