Commit Graph

806 Commits

Author SHA1 Message Date
Dale Johannesen
d0cf2585a0 Revert 122353-122355 for the moment, they broke stuff.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122360 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 21:22:27 +00:00
Dale Johannesen
a83bf35d16 Add a new transform to DAGCombiner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122355 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 20:10:51 +00:00
Dale Johannesen
5ecc340e34 Get the type of a shift from the shift, not from its shift
count operand.  These should be the same but apparently are
not always, and this is cleaner anyway.  This improves the
code in an existing test.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122354 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 20:06:19 +00:00
Dale Johannesen
efc96dd38c Shift by the word size is invalid IR; don't create it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122353 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 20:00:06 +00:00
Chris Lattner
90b0364cff fix some typos
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122349 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 18:05:22 +00:00
Chris Lattner
f1b4eafbfe rename MVT::Flag to MVT::Glue. "Flag" is a terrible name for
something that just glues two nodes together, even if it is
sometimes used for flags.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122310 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21 02:38:05 +00:00
Dale Johannesen
025cc6e1be Cosmetic changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122259 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-20 20:10:50 +00:00
Bob Wilson
d727343a40 Fix a DAGCombiner crash when folding binary vector operations with constant
BUILD_VECTOR operands where the element type is not legal.  I had previously
changed this code to insert TRUNCATE operations, but that was just wrong.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122102 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17 23:06:49 +00:00
Dale Johannesen
f5daf8bb7f Add a transform to DAG Combiner. This improves the
code for the case where 32-bit divide by constant is
turned into 64-bit multiply by constant.  8771012.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122090 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-17 21:45:49 +00:00
Chris Lattner
33e77d3cb9 take care of some todos, transforming [us]mul_lohi into
a wider mul if the wider mul is legal.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121848 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 06:04:19 +00:00
Chris Lattner
1a0fbe2cf4 when transforming a MULHS into a wider MUL, there is no need to SRA the
result, the top bits are truncated off anyway, just use SRL.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121846 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15 05:51:39 +00:00
Chris Lattner
de1c3605a6 Add a couple dag combines to transform mulhi/mullo into a wider multiply
when the wider type is legal.  This allows us to compile:

define zeroext i16 @test1(i16 zeroext %x) nounwind {
entry:
	%div = udiv i16 %x, 33
	ret i16 %div
}

into:

test1:                                  # @test1
	movzwl	4(%esp), %eax
	imull	$63551, %eax, %eax      # imm = 0xF83F
	shrl	$21, %eax
	ret

instead of:

test1:                                  # @test1
        movw    $-1985, %ax             # imm = 0xFFFFFFFFFFFFF83F
        mulw    4(%esp)
        andl    $65504, %edx            # imm = 0xFFE0
        movl    %edx, %eax
        shrl    $5, %eax
        ret

Implementing rdar://8760399 and example #4 from:
http://blog.regehr.org/archives/320

We should implement the same thing for [su]mul_hilo, but I don't
have immediate plans to do this.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121696 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-13 08:39:01 +00:00
Eric Christopher
503a64dcd4 80-col fixups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121356 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-09 04:48:06 +00:00
Jay Foad
40f8f6264d PR5207: Change APInt methods trunc(), sext(), zext(), sextOrTrunc() and
zextOrTrunc(), and APSInt methods extend(), extOrTrunc() and new method
trunc(), to be const and to return a new value instead of modifying the
object in place.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121120 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-07 08:25:19 +00:00
Bob Wilson
bebfbc560b Fix a comment typo.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120235 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-28 06:51:19 +00:00
Wesley Peck
bf17cfa3f9 Renaming ISD::BIT_CONVERT to ISD::BITCAST to better reflect the LLVM IR concept.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119990 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-23 03:31:01 +00:00
Duncan Sands
b9064bb964 Fix thinko: we must turn select(anyext, sext) into sext(select)
not anyext(select).  Spotted by Frits van Bommel.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119739 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 21:16:28 +00:00
Duncan Sands
dcfd3a798f The DAGCombiner was threading select over pairs of extending loads even
if the extension types were not the same.  The result was that if you
fed a select with sext and zext loads, as in the testcase, then it
would get turned into a zext (or sext) of the select, which is wrong
in the cases when it should have been an sext (resp. zext).  Reported
and diagnosed by Sebastien Deldon.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119728 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18 20:05:18 +00:00
Dan Gohman
6a559cd695 Fix DAGCombiner to avoid folding a sext-in-reg or similar through a shl
in order to fold it into a load.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118471 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-09 01:54:35 +00:00
Eric Christopher
d81f17acb4 Just return undef for invalid masks or elts, and since we're doing that,
just do it earlier too.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118195 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 20:44:42 +00:00
Eric Christopher
caebdd44f3 If we have an undef mask our Elt will be -1 for our access, handle
this by using an undef as a pointer.

Fixes rdar://8625016


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118164 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 09:36:40 +00:00
Dan Gohman
394d6298bc Fix DAGCombiner to avoid going into an infinite loop when it
encounters (and:i64 (shl:i64 (load:i64), 1), 0xffffffff).
This fixes rdar://8606584.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118143 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-03 01:47:46 +00:00
Bob Wilson
46455096be Remove DAG combiner patch to fold vector splats. Instcombiner does it now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117720 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-29 22:03:02 +00:00
Bob Wilson
0f1db1a6c6 Teach the DAG combiner to fold a splat of a splat. Radar 8597790.
Also do some minor refactoring to reduce indentation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117558 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-28 17:06:14 +00:00
Dan Gohman
f96e4bd2a3 Make CodeGen TBAA-aware.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116890 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-20 00:31:05 +00:00
Evan Cheng
2a135ae530 This DAG combine BRCOND transformation can look pass truncate of the operand:
//   %a = ...                                                                                                                                                                                  
    //   %b = and i32 %a, 2                                                                                                                                                                        
    //   %c = srl i32 %b, 1                                                                                                                                                                        
    //   brcond i32 %c ...                                                                                                                                                                         
    //                                                                                                                                                                                             
    // into                                                                                                                                                                                        
    //                                                                                                                                                                                             
    //   %a = ...                                                                                                                                                                                  
    //   %b = and i32 %a, 2                                                                                                                                                                        
    //   %c = setcc eq %b, 0                                                                                                                                                                       
    //   brcond %c ...

Make sure it restores local variable N1, which corresponds to the condition operand if it fails to match.

This apparently breaks TCE but since that backend isn't in the tree I don't have a test for it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115571 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-04 22:41:01 +00:00
Chris Lattner
2831a19495 fix rdar://8494845 + PR8244 - a miscompile exposed by my patch in r101350
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115294 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-01 05:36:09 +00:00
Owen Anderson
ed1088afb5 A select between a constant and zero, when fed by a bit test, can be efficiently
lowered using a series of shifts.
Fixes <rdar://problem/8285015>.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114599 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-22 22:58:22 +00:00
Owen Anderson
bc146b0a4d Reimplement r114460 in target-independent DAGCombine rather than target-dependent, by using
the predicate to discover the number of sign bits.  Enhance X86's target lowering to provide
a useful response to this query.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114473 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 20:42:50 +00:00
Chris Lattner
6229d0acb8 update a bunch of code to use the MachinePointerInfo version of getStore.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114461 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 18:41:36 +00:00
Chris Lattner
da2d8e1032 eliminate an old SelectionDAG::getTruncStore method, propagating
MachinePointerInfo around more.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114452 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 17:42:31 +00:00
Chris Lattner
3d6ccfba31 propagate MachinePointerInfo through various uses of the old
SelectionDAG::getExtLoad overload, and eliminate it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114446 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 17:04:51 +00:00
Chris Lattner
fa45901eaa convert dagcombine off the old form of getLoad. This fixes several bugs
with SVOffset computation.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114442 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 16:08:50 +00:00
Chris Lattner
f165806655 simplify DAGCombiner::SimplifySelectOps step #2/2.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114437 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 15:58:55 +00:00
Chris Lattner
1806161a0b substantially reduce indentation and simplify DAGCombiner::SimplifySelectOps.
no functionality change (step #1)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114436 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 15:46:59 +00:00
Chris Lattner
85ca106632 a few more trivial updates. This fixes PerformInsertVectorEltInMemory to not
pass a completely incorrect SrcValue, which would result in a miscompile with
combiner-aa.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114411 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-21 07:32:19 +00:00
Owen Anderson
4a9f150926 When TCO is turned on, it is possible to end up with aliasing FrameIndex's. Therefore,
CombinerAA cannot assume that different FrameIndex's never alias, but can instead use
MachineFrameInfo to get the actual offsets of these slots and check for actual aliasing.

This fixes CodeGen/X86/2010-02-19-TailCallRetAddrBug.ll and CodeGen/X86/tailcallstack64.ll
when CombinerAA is enabled, modulo a different register allocation sequence.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114348 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-20 20:39:59 +00:00
Owen Anderson
0dcc814276 Revert r114312 while I sort out some issues.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114313 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-19 21:01:26 +00:00
Owen Anderson
d910fb2f12 Tentatively enabled DAGCombiner Alias Analysis by default. As far as I know,
r114268 fixed the last of the blockers to enabling it.  I will be monitoring
for failures.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114312 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-19 19:51:55 +00:00
Dan Gohman
24bde5bce1 Don't narrow the load and store in a load+twiddle+store sequence unless
there are clearly no stores between the load and the store. This fixes
this miscompile reported as PR7833.

This breaks the test/CodeGen/X86/narrow_op-2.ll optimization, which is
safe, but awkward to prove safe. Move it to X86's README.txt.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112861 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-02 21:18:42 +00:00
Nate Begeman
e0efc216eb Fix a crash in the dag combiner caused by ConstantFoldBIT_CONVERTofBUILD_VECTOR calling itself
recursively and returning a SCALAR_TO_VECTOR node, but assuming the input was always a BUILD_VECTOR.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109519 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-27 18:02:18 +00:00
Owen Anderson
54026c0f1b Remove r108639 now that it is handled by InstCombine instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108688 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-19 08:10:24 +00:00
Owen Anderson
3ecdfafe3b Add a DAGCombine xform to fold away redundant float->double->float conversions around sqrt instructions.
I am assured by people more knowledgeable than me that there are no rounding issues in eliminating this.

This fixed <rdar://problem/8197504>.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108639 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-18 08:47:54 +00:00
Duncan Sands
3472766f9e Convert some tab stops into spaces.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@108130 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-12 08:16:59 +00:00
Bob Wilson
f1d93ca920 Reenable DAG combining for vector shuffles. It looks like it was temporarily
disabled and then never turned back on again.  Adjust some tests, one because
this change avoids an unnecessary instruction, and the other to make it
continue testing what it was intended to test.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107941 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-09 00:38:12 +00:00
Benjamin Kramer
cde51108de Merge the duplicated iabs optimization in DAGCombiner and let it detected a few more idioms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107868 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-08 12:09:56 +00:00
Evan Cheng
bcc8017c73 Move getExtLoad() and (some) getLoad() DebugLoc argument after EVT argument for consistency sake.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107820 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-07 22:15:37 +00:00
Devang Patel
0d881dabc1 Propagate debug loc.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107710 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-06 22:08:15 +00:00
Bob Wilson
8674949513 Unlike other targets, ARM now uses BUILD_VECTORs post-legalization so they
can't be changed arbitrarily by the DAGCombiner without checking if it is
running after legalization.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107097 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-28 23:40:25 +00:00
Duncan Sands
b447c4e65b Remove variables which are assigned to but for which the value
is not used.  Spotted by gcc-4.6.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106854 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-25 14:48:39 +00:00
Dan Gohman
4e39e9da0f Reapply r106634, now that the bug it exposed is fixed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106746 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24 14:30:44 +00:00
Daniel Dunbar
cbe762b5d1 Revert r106263, "Fold the ShrinkDemandedOps pass into the regular DAGCombiner pass,"... it was causing both 'file' (with clang) and 176.gcc (with llvm-gcc) to be miscompiled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106634 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-23 17:09:26 +00:00
Jim Grosbach
9a526495e0 Some targets don't require the fencing MEMBARRIER instructions surrounding
atomic intrinsics, either because the use locking instructions for the
atomics, or because they perform the locking directly. Add support in the
DAG combiner to fold away the fences.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106630 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-23 16:07:42 +00:00
Dan Gohman
8a7f7426ee Fold the ShrinkDemandedOps pass into the regular DAGCombiner pass,
which is faster, simpler, and less surprising.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106263 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-18 01:05:21 +00:00
Dale Johannesen
86234c30a7 Fix another variant of PR 7191. Also add a testcase
Mon Ping provided; unfortunately bugpoint failed to
reduce it, but I think it's important to have a test for
this in the suite.  8023512.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104624 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-25 18:47:23 +00:00
Dale Johannesen
61734eb117 Fix PR 7191. I have been unable to create a .ll file that fails, sorry.
(oye, a word which should be better known to people writing tree
traversals, means grandchild.)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104619 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-25 17:50:03 +00:00
Bob Wilson
70fe6643d6 Clean up extra whitespace.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-21 23:53:55 +00:00
Bob Wilson
78f006acdf Change CodeGen/ARM/2009-11-02-NegativeLane.ll to use 16-bit vector elements
so that it will continue to test what it was meant to test when I commit a
separate change for better support of BUILD_VECTOR and VECTOR_SHUFFLE for Neon.
Fix a DAG combiner crash exposed by this test change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104380 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-21 21:05:32 +00:00
Bob Wilson
492fd454ca Optimize away insertelement of an undef value. This shows up in
test/Codegen/ARM/reg_sequence.ll but it doesn't affect the generated code
because the coalescer cleans it up.  Radar 7998853.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104185 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19 23:42:58 +00:00
Evan Cheng
0a942dbb1e Intrinsics which do a vector compare (results are all zero or all ones) are modeled as icmp / fcmp + sext. This is turned into a vsetcc by dag combine (yes, not a good long term solution). The targets can then isel the vsetcc to the appropriate instruction.
The trouble arises when the result of a vector cmp + sext is then and'ed with all ones. Instcombine will turn it into a vector cmp + zext, dag combiner will miss turning it into a vsetcc and hell breaks loose after that.

Teach dag combine to turn a vector cpm + zest into a vsetcc + and 1. This fixes rdar://7923010.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104094 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-19 01:08:17 +00:00
Evan Cheng
28dad2a5ca Sink dag combine's post index load / store code that swap base ptr and index into the target hook. Only the target knows whether the swap is safe. In Thumb2 mode, the offset must be an immediate. rdar://7998649
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104060 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 21:31:17 +00:00
Evan Cheng
a083988c8a FIX PR7158. SimplifyVBinOp was asserting when it fails to constant fold (op (build_vector), (build_vector)).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104004 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-18 00:03:40 +00:00
Evan Cheng
aad753bbbd Be careful with operand promotion. For a binary operation, the source operands may be the same. PR7018. rdar://7939869.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103419 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-10 19:03:57 +00:00
Dan Gohman
3ce89f47de Apply a patch from Jan Sjodin to fix a compiler abort on vector
comparisons sign-extended to a different bitwidth than the
comparison operands.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102721 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-30 17:19:19 +00:00
Evan Cheng
b3a3d5e858 Try operation promotion only if regular dag combine and target-specific ones failed to do anything.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102492 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-28 07:10:39 +00:00
Evan Cheng
ac7eae5b89 - When legal, promote a load to zextload rather than ext load.
- Catch more further dag combine opportunities as result of operand promotion, e.g. (i32 anyext (i16 trunc (i32 x))) -> (i32 x)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102455 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-27 19:48:13 +00:00
Evan Cheng
95c57ea182 When a load operand is promoted to an extload, replace other uses with uses of extload result truncated.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102236 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-24 04:43:44 +00:00
Dan Gohman
a7bcef1bce Apply a fix for a vector setcc dagcombine from Jan Sjodin. No
testcase yet, as the testcase now fails downstream.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102228 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-24 01:17:30 +00:00
Evan Cheng
caf7740f96 Code refactoring.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102202 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-23 19:10:30 +00:00
Evan Cheng
07c4e1085d - It's not safe to promote rotates (at least not trivially).
- Some code refactoring.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@102111 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-22 20:19:46 +00:00
Bill Wendling
86c5abb4c0 The visitXOR method can return the same SDNode. If so, we don't want to delete
it as it's not dead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101855 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-20 01:25:01 +00:00
Evan Cheng
4c26e93e89 More progress on promoting i16 operations to i32 for x86. Work in progress.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101808 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-19 19:29:22 +00:00
Evan Cheng
e5b51ac770 More work to allow dag combiner to promote 16-bit ops to 32-bit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101621 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-17 06:13:15 +00:00
Evan Cheng
003d7c4b5d (i32 sext_in_reg (i32 aext (i16 x)), i16) -> (i32 sext x). No known test case until -promote-16bit is enabled.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101551 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16 22:26:19 +00:00
Evan Cheng
64b7bf71e8 Adding support for dag combiner to promote operations for profit. This requires target specific queries. For example, x86 should promote i16 to i32 when it does not impact load folding.
x86 support is off by default. It can be enabled with -promote-16bit.

Work in progress.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101448 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16 06:14:10 +00:00
Chris Lattner
e6987587d6 enhance the load/store narrowing optimization to handle a
tokenfactor in between the load/store.  This allows us to 
optimize test7 into:

_test7:                                 ## @test7
## BB#0:                                ## %entry
	movl	(%rdx), %eax
                                        ## kill: SIL<def> ESI<kill>
	movb	%sil, 5(%rdi)
	ret

instead of:

_test7:                                 ## @test7
## BB#0:                                ## %entry
	movl	4(%esp), %ecx
	movl	$-65281, %eax           ## imm = 0xFFFFFFFFFFFF00FF
	andl	4(%ecx), %eax
	movzbl	8(%esp), %edx
	shll	$8, %edx
	addl	%eax, %edx
	movl	12(%esp), %eax
	movl	(%eax), %eax
	movl	%edx, 4(%ecx)
	ret



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101355 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15 06:10:49 +00:00
Chris Lattner
6dc868581b teach codegen to turn trunc(zextload) into load when possible.
This doesn't occur much at all, it only seems to formed in the case
when the trunc optimization kicks in due to phase ordering.  In that
case it is saves a few bytes on x86-32.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101350 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15 05:40:59 +00:00
Chris Lattner
efcddc3325 add a simple dag combine to replace trivial shl+lshr with
and.  This happens with the store->load narrowing stuff.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101348 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15 05:28:43 +00:00
Chris Lattner
2392ae7d73 Implement rdar://7860110 (also in target/readme.txt) narrowing
a load/or/and/store sequence into a narrower store when it is
safe.  Daniel tells me that clang will start producing this sort
of thing with bitfields, and this does  trigger a few dozen times
on 176.gcc produced by llvm-gcc even now.

This compiles code like CodeGen/X86/2009-05-28-DAGCombineCrash.ll 
into:

        movl    %eax, 36(%rdi)

instead of:

        movl    $4294967295, %eax       ## imm = 0xFFFFFFFF
        andq    32(%rdi), %rax
        shlq    $32, %rcx
        addq    %rax, %rcx
        movq    %rcx, 32(%rdi)

and each of the testcases into a single store.  Each of them used
to compile into craziness like this:

_test4:
	movl	$65535, %eax            ## imm = 0xFFFF
	andl	(%rdi), %eax
	shll	$16, %esi
	addl	%eax, %esi
	movl	%esi, (%rdi)
	ret




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101343 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15 04:48:01 +00:00
Dan Gohman
46510a73e9 Add const qualifiers to CodeGen's use of LLVM IR constructs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101334 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15 01:51:59 +00:00
Dan Gohman
58c2587ed8 Remove unnecessary parens.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101010 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-12 02:24:01 +00:00
Ted Kremenek
d0e88f3596 Fix -Wsign-compare warning (issued by clang++).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100799 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-08 18:49:30 +00:00
Chris Lattner
7f893c0712 fix 80 col violation, patch by Alastair Lynn
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100639 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-07 18:13:33 +00:00
Evan Cheng
255f20f7f7 Fix sdisel memcpy, memset, memmove lowering:
1. Makes it possible to lower with floating point loads and stores.
2. Avoid unaligned loads / stores unless it's fast.
3. Fix some memcpy lowering logic bug related to when to optimize a
   load from constant string into a constant.
4. Adjust x86 memcpy lowering threshold to make it more sane.
5. Fix x86 target hook so it uses vector and floating point memory
   ops more effectively.
rdar://7774704


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@100090 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-01 06:04:33 +00:00
Chris Lattner
f2f64e9063 fix PR6533 by updating the br(xor) code to remember the case
when it looked past a trunc.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98203 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-10 23:46:44 +00:00
Dan Gohman
8f78e3c87d Fix another bitwidth calculation to handle vector types; based on a
patch by Micah Villmow for PR6572.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98188 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-10 21:04:53 +00:00
Dan Gohman
6900a39d28 Fix more code to work properly with vector operands. Based on
a patch my Micah Villmow for PR6465.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97692 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-04 00:23:16 +00:00
Bill Wendling
32f9eb2bc3 Use APInt instead of zext value.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97631 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03 01:58:01 +00:00
Bill Wendling
7d9f2b93a3 This test case:
long test(long x) { return (x & 123124) | 3; }

Currently compiles to:

_test:
        orl     $3, %edi
        movq    %rdi, %rax
        andq    $123127, %rax
        ret

This is because instruction and DAG combiners canonicalize

  (or (and x, C), D) -> (and (or, D), (C | D))

However, this is only profitable if (C & D) != 0. It gets in the way of the
3-addressification because the input bits are known to be zero.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97616 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-03 00:35:56 +00:00
Dan Gohman
5b870aff81 Fix several places to handle vector operands properly.
Based on a patch by Micah Villmow for PR6438.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97538 91177308-0d34-0410-b5e6-96231b3b80d8
2010-03-02 02:14:38 +00:00
Evan Cheng
2c755ba12a Re-apply 97040 with fix. This survives a ppc self-host llvm-gcc bootstrap.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97310 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-27 07:36:59 +00:00
Daniel Dunbar
cfe30effbb Speculatively revert r97011, "Re-apply 96540 and 96556 with fixes.", again in
the hopes of fixing PPC bootstrap.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97040 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-24 17:05:47 +00:00
Evan Cheng
97e6b8390b Re-apply 96540 and 96556 with fixes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@97011 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-24 01:42:31 +00:00
Duncan Sands
3eba667081 Revert commits 96556 and 96640, because commit 96556 breaks the
dragonegg self-host build.  I reverted 96640 in order to revert
96556 (96640 goes on top of 96556), but it also looks like with
both of them applied the breakage happens even earlier.  The
symptom of the 96556 miscompile is the following crash:

  llvm[3]: Compiling AlphaISelLowering.cpp for Release build
  cc1plus: /home/duncan/tmp/tmp/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:4982: void llvm::SelectionDAG::ReplaceAllUsesWith(llvm::SDNode*, llvm::SDNode*, llvm::SelectionDAG::DAGUpdateListener*): Assertion `(!From->hasAnyUseOfValue(i) || From->getValueType(i) == To->getValueType(i)) && "Cannot use this version of ReplaceAllUsesWith!"' failed.
  Stack dump:
  0.	Running pass 'X86 DAG->DAG Instruction Selection' on function '@_ZN4llvm19AlphaTargetLowering14LowerOperationENS_7SDValueERNS_12SelectionDAGE'
  g++: Internal error: Aborted (program cc1plus)

This occurs when building LLVM using LLVM built by LLVM (via
dragonegg).  Probably LLVM has miscompiled itself, though it
may have miscompiled GCC and/or dragonegg itself: at this point
of the self-host build, all of GCC, LLVM and dragonegg were built
using LLVM.  Unfortunately this kind of thing is extremely hard
to debug, and while I did rummage around a bit I didn't find any
smoking guns, aka obviously miscompiled code.

Found by bisection.

r96556 | evancheng | 2010-02-18 03:13:50 +0100 (Thu, 18 Feb 2010) | 5 lines

Some dag combiner goodness:
Transform br (xor (x, y)) -> br (x != y)
Transform br (xor (xor (x,y), 1)) -> br (x == y)
Also normalize (and (X, 1) == / != 1 -> (and (X, 1)) != / == 0 to match to "test on x86" and "tst on arm"

r96640 | evancheng | 2010-02-19 01:34:39 +0100 (Fri, 19 Feb 2010) | 16 lines

Transform (xor (setcc), (setcc)) == / != 1 to
(xor (setcc), (setcc)) != / == 1.

e.g. On x86_64
  %0 = icmp eq i32 %x, 0
  %1 = icmp eq i32 %y, 0
  %2 = xor i1 %1, %0
  br i1 %2, label %bb, label %return
=>
	testl   %edi, %edi
	sete    %al
	testl   %esi, %esi
	sete    %cl
	cmpb    %al, %cl
	je      LBB1_2



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96672 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-19 11:30:41 +00:00
Evan Cheng
89bb7b5640 Some dag combiner goodness:
Transform br (xor (x, y)) -> br (x != y)
Transform br (xor (xor (x,y), 1)) -> br (x == y)
Also normalize (and (X, 1) == / != 1 -> (and (X, 1)) != / == 0 to match to "test on x86" and "tst on arm"


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96556 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-18 02:13:50 +00:00
David Greene
1e559443a1 Add non-temporal flags and remove an assumption of default arguments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96240 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-15 17:00:31 +00:00
Dan Gohman
f451cb870e Fix "the the" and similar typos.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95781 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-10 16:03:48 +00:00
Mon P Wang
87c46d8a0e Improve EXTRACT_VECTOR_ELT patch based on comments from Duncan
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95012 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 22:15:09 +00:00
Mon P Wang
c6654ec498 Fixed a couple of optimization with EXTRACT_VECTOR_ELT that assumes the result
type is the same as the element type of the vector.  EXTRACT_VECTOR_ELT can
be used to extended the width of an integer type.  This fixes a bug for
Generic/vector-casts.ll on a ppc750.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94990 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-01 19:03:18 +00:00
Evan Cheng
8c7ecaf524 Implement cond ? -1 : 0 with sbb.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94490 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-26 02:00:44 +00:00