Commit Graph

1578 Commits

Author SHA1 Message Date
Chris Lattner e260ed8628 Add support for CombineTo, allowing the dag combiner to replace nodes with
multiple results.

Use this support to implement trivial store->load forwarding, implementing
CodeGen/PowerPC/store-load-fwd.ll.  Though this is the most simple case and
can be extended in the future, it is still useful.  For example, it speeds
up 197.parser by 6.2% by avoiding an LSU reject in xalloc:

        stw r6, lo16(l5_end_of_array)(r2)
        addi r2, r5, -4
        stwx r5, r4, r2
-       lwzx r5, r4, r2
-       rlwinm r5, r5, 0, 0, 30
        stwx r5, r4, r2
        lwz r2, -4(r4)
        ori r2, r2, 1

llvm-svn: 23690
2005-10-10 22:04:48 +00:00
Nate Begeman 6828ed9bfd Teach the DAGCombiner several new tricks, teaching it how to turn
sext_inreg into zext_inreg based on the signbit (fires a lot), srem into
urem, etc.

llvm-svn: 23688
2005-10-10 21:26:48 +00:00
Chris Lattner 7730924067 Fix comment
llvm-svn: 23686
2005-10-10 16:52:03 +00:00
Chris Lattner 3d1d4a3d12 Add ISD::ADD to MaskedValueIsZero
llvm-svn: 23685
2005-10-10 16:51:40 +00:00
Chris Lattner 6a49b7cabb add a todo for something I noticed
llvm-svn: 23679
2005-10-09 22:59:08 +00:00
Chris Lattner 1d3dc00674 (X & Y) & C == 0 if either X&C or Y&C are zero
llvm-svn: 23678
2005-10-09 22:12:36 +00:00
Nate Begeman 2042aa5b92 Lo and behold, the last bits of SelectionDAG.cpp have been moved over.
llvm-svn: 23665
2005-10-08 00:29:44 +00:00
Chris Lattner fb12624a3f implement CodeGen/PowerPC/div-2.ll:test2-4 by propagating zero bits through
C-X's

llvm-svn: 23662
2005-10-07 15:30:32 +00:00
Chris Lattner 5bcd0dd811 Turn sdivs into udivs when we can prove the sign bits are clear. This
implements CodeGen/PowerPC/div-2.ll

llvm-svn: 23659
2005-10-07 06:10:46 +00:00
Nate Begeman bd7df030d2 Check in some more DAGCombiner pieces
llvm-svn: 23639
2005-10-05 21:43:42 +00:00
Chris Lattner a49e16fefa implement visitBR_CC so that PowerPC/inverted-bool-compares.ll passes
with the dag combiner.  This speeds up espresso by 8%, reaching performance
parity with the dag-combiner-disabled llc.

llvm-svn: 23636
2005-10-05 06:47:48 +00:00
Chris Lattner 06f1d0f73a Add a new HandleNode class, which is used to handle (haha) cases in the
dead node elim and dag combiner passes where the root is potentially updated.
This fixes a fixme in the dag combiner.

llvm-svn: 23634
2005-10-05 06:35:28 +00:00
Chris Lattner a6895d180e Implement the code for PowerPC/inverted-bool-compares.ll, even though it
that testcase still does not pass with the dag combiner.  This is because
not all forms of br* are folded yet.

Also, when we combine a node into another one, delete the node immediately
instead of waiting for the node to potentially come up in the future.

llvm-svn: 23632
2005-10-05 06:11:08 +00:00
Chris Lattner 746d50a01a Fix a crash compiling Olden/tsp
llvm-svn: 23630
2005-10-05 04:45:43 +00:00
Chris Lattner 6f3b577ee6 Add FP versions of the binary operators, keeping the int and fp worlds seperate.
Though I have done extensive testing, it is possible that this will break
things in configs I can't test.  Please let me know if this causes a problem
and I'll fix it ASAP.

llvm-svn: 23504
2005-09-28 22:28:18 +00:00
Nate Begeman c760f80fed Stub out the rest of the DAG Combiner. Just need to fill in the
select_cc bits and then wrap it in a convenience function for  use with
regular select.

llvm-svn: 23389
2005-09-19 22:34:01 +00:00
Nate Begeman 24a7eca282 More DAG combining. Still need the branch instructions, and select_cc
llvm-svn: 23371
2005-09-16 00:54:12 +00:00
Chris Lattner bd39c1a4c6 Add a missing #include, patch courtesy of Baptiste Lepilleur.
llvm-svn: 23302
2005-09-09 23:53:39 +00:00
Nate Begeman 049b748c76 Last round of 2-node folds from SD.cpp. Will move on to 3 node ops such
as setcc and select next.

llvm-svn: 23295
2005-09-09 19:49:52 +00:00
Nate Begeman 85c1cc4523 Move yet more folds over to the dag combiner from sd.cpp
llvm-svn: 23278
2005-09-08 20:18:10 +00:00
Nate Begeman 2cc2c9a79c Another round of dag combiner changes. This fixes some missing XOR folds
as well as fixing how we replace old values with new values.

llvm-svn: 23260
2005-09-07 23:25:52 +00:00
Nate Begeman 6791d63e55 Implement a common missing fold, (add (add x, c1), c2) -> (add x, c1+c2).
This restores all of stanford to being identical with and without the dag
combiner with the add folding turned off in sd.cpp.

llvm-svn: 23258
2005-09-07 16:09:19 +00:00
Nate Begeman 007c650699 Add an option to the DAG Combiner to enable it for beta runs, and turn on
that option for PowerPC's beta.

llvm-svn: 23253
2005-09-07 00:15:36 +00:00
Nate Begeman d23739d020 Next round of DAGCombiner changes. This version now passes all the tests
I have run so far when run before Legalize.  It still needs to pick up the
SetCC folds, and nodes that use SetCC.

llvm-svn: 23243
2005-09-06 04:43:02 +00:00
Nate Begeman 7cea6ef16e Next round of DAG Combiner changes. Just need to support multiple return
values, and then we should be able to hook it up.

llvm-svn: 23231
2005-09-02 21:18:40 +00:00
Nate Begeman 2504fe2613 Implement first round of feedback from chris (there's still a couple things
left to do).

llvm-svn: 23195
2005-09-01 23:24:04 +00:00
Nate Begeman e8f78d1aab Add the rest of the currently implemented visit routines to the switch
statement in visit().

llvm-svn: 23185
2005-09-01 00:33:32 +00:00
Nate Begeman 21158fc485 First pass at the DAG Combiner. It isn't used anywhere yet, but it should
be mostly functional.  It currently has all folds from SelectionDAG.cpp
that do not involve a condition code.

llvm-svn: 23184
2005-09-01 00:19:25 +00:00