Commit Graph

55 Commits

Author SHA1 Message Date
Chris Lattner 3b409a85eb Clear a bit in this file that was causing a miscompilation of 178.galgel.
llvm-svn: 23980
2005-10-25 18:57:30 +00:00
Chris Lattner 9faa5b7a9a BuildSDIV and BuildUDIV only work for i32/i64, but they don't check that
the input is that type, this caused a failure on gs on X86 last night.
Move the hard checks into Build[US]Div since that is where decisions like
this should be made.

llvm-svn: 23881
2005-10-22 18:50:15 +00:00
Chris Lattner 75ea5b10bf add a case missing from the dag combiner that exposed the failure on
2005-10-21-longlonggtu.ll.

llvm-svn: 23875
2005-10-21 21:23:25 +00:00
Nate Begeman 8f62cd32ad Fix a typo in the dag combiner, so that this can work on i64 targets
llvm-svn: 23856
2005-10-21 01:51:45 +00:00
Nate Begeman 4dd383120f Invert the TargetLowering flag that controls divide by consant expansion.
Add a new flag to TargetLowering indicating if the target has really cheap
  signed division by powers of two, make ppc use it.  This will probably go
  away in the future.
Implement some more ISD::SDIV folds in the dag combiner
Remove now dead code in the x86 backend.

llvm-svn: 23853
2005-10-21 00:02:42 +00:00
Nate Begeman 7efe53d90b Fix a couple bugs in the const div stuff where we'd generate MULHS/MULHU
for types that aren't legal, and fail a divisor is less than zero
comparison, which would cause us to drop a subtract.

llvm-svn: 23846
2005-10-20 17:45:03 +00:00
Chris Lattner a6efeb01f9 don't use llabs with apparently VC++ doesn't have
llvm-svn: 23845
2005-10-20 17:01:00 +00:00
Nate Begeman c6f067a8c4 Move the target constant divide optimization up into the dag combiner, so
that the nodes can be folded with other nodes, and we can not duplicate
code in every backend.  Alpha will probably want this too.

llvm-svn: 23835
2005-10-20 02:15:44 +00:00
Chris Lattner 6c14c35bd7 Fold (select C, load A, load B) -> load (select C, A, B). This happens quite
a lot throughout many programs.  In particular, specfp triggers it a bunch for
constant FP nodes when you have code like  cond ? 1.0 : -1.0.

If the PPC ISel exposed the loads implicit in pic references to external globals,
we would be able to eliminate a load in cases like this as well:

%X = external global int
%Y = external global int
int* %test4(bool %C) {
        %G = select bool %C, int* %X, int* %Y
        ret int* %G
}

Note that this breaks things that use SrcValue's (see the fixme), but since nothing
uses them yet, this is ok.

Also, simplify some code to use hasOneUse() on an SDOperand instead of hasNUsesOfValue directly.

llvm-svn: 23781
2005-10-18 06:04:22 +00:00
Nate Begeman 418c6e4045 Implement some feedback from Chris re: constant canonicalization
llvm-svn: 23777
2005-10-18 00:28:13 +00:00
Nate Begeman ec48a1bfbd fold fmul X, +2.0 -> fadd X, X;
llvm-svn: 23774
2005-10-17 20:40:11 +00:00
Chris Lattner eeb2bda2fa add a trivial fold
llvm-svn: 23764
2005-10-17 01:07:11 +00:00
Chris Lattner e540800d5a Fix this logic.
llvm-svn: 23756
2005-10-15 22:35:40 +00:00
Chris Lattner 17cc9edd33 Add a case we were missing that was causing us to fail CodeGen/PowerPC/rlwinm.ll:test3
llvm-svn: 23755
2005-10-15 22:18:08 +00:00
Nate Begeman 6e673b24d3 fold sext_in_reg, sext_in_reg where both have the same VT. This was
popping up in Fourinarow.

llvm-svn: 23722
2005-10-14 01:29:07 +00:00
Nate Begeman d59e5a7abb Relax the checking on zextload generation a bit, since as sabre pointed out
you could be AND'ing with the result of a shift that shifts out all the
bits you care about, in addition to a constant.

Also, move over an add/sub_parts fold from legalize to the dag combiner,
where it works for things other than constants.  Woot!

llvm-svn: 23720
2005-10-14 01:12:21 +00:00
Chris Lattner b8282987f4 Fix the trunc(load) case, finally allowing crafty and povray to pass
llvm-svn: 23718
2005-10-13 22:10:05 +00:00
Chris Lattner dbc5ae3109 Fix some bugs in (sext (load x))
llvm-svn: 23717
2005-10-13 21:52:31 +00:00
Nate Begeman 8e022b3d89 Fix the remaining DAGCombiner issues pointed out by sabre. This should fix
the remainder of the failures introduced by my patch last night.

llvm-svn: 23714
2005-10-13 18:34:58 +00:00
Chris Lattner a80f1f6e72 Fix a minor bug in the dag combiner that broke pcompress2 and some other
tests.

llvm-svn: 23713
2005-10-13 18:16:34 +00:00
Nate Begeman 02b23c6065 Move some Legalize functionality over to the DAGCombiner where it belongs.
Kill some dead code.

llvm-svn: 23706
2005-10-13 03:11:28 +00:00
Nate Begeman 70d28c5e32 Fix a potential bug with two combine-to's back to back that chris pointed
out, where after the first CombineTo() call, the node the second CombineTo
wishes to replace may no longer exist.

Fix a very real bug with the truncated load optimization on little endian
targets, which do not need a byte offset added to the load.

llvm-svn: 23704
2005-10-12 23:18:53 +00:00
Nate Begeman 8caf81d617 More cool stuff for the dag combiner. We can now finally handle things
like turning:

_foo:
        fctiwz f0, f1
        stfd f0, -8(r1)
        lwz r2, -4(r1)
        rlwinm r3, r2, 0, 16, 31
        blr

into
_foo:
        fctiwz f0,f1
        stfd f0,-8(r1)
        lhz r3,-2(r1)
        blr

Also removed an unncessary constraint from sra -> srl conversion, which
should take care of hte only reason we would ever need to handle sra in
MaskedValueIsZero, AFAIK.

llvm-svn: 23703
2005-10-12 20:40:40 +00:00
Chris Lattner 514f058be1 Fix a powerpc crash on CodeGen/Generic/llvm-ct-intrinsics.ll
llvm-svn: 23694
2005-10-11 17:56:34 +00:00
Chris Lattner c38fb8e2a1 Add a canonicalization that got lost, fixing PowerPC/fold-li.ll:SUB
llvm-svn: 23693
2005-10-11 06:07:15 +00:00
Chris Lattner cc6e53e6ee clean up some corner cases
llvm-svn: 23692
2005-10-10 23:00:08 +00:00
Chris Lattner 04c737091f Implement trivial DSE. If two stores are neighbors and store to the same
location, replace them with a new store of the last value.  This occurs
in the same neighborhood in 197.parser, speeding it up about 1.5%

llvm-svn: 23691
2005-10-10 22:31:19 +00:00
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