Commit Graph

731 Commits

Author SHA1 Message Date
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