826 Commits

Author SHA1 Message Date
Chandler Carruth
63974b2144 Initial CodeGen support for CTTZ/CTLZ where a zero input produces an
undefined result. This adds new ISD nodes for the new semantics,
selecting them when the LLVM intrinsic indicates that the undef behavior
is desired. The new nodes expand trivially to the old nodes, so targets
don't actually need to do anything to support these new nodes besides
indicating that they should be expanded. I've done this for all the
operand types that I could figure out for all the targets. Owners of
various targets, please review and let me know if any of these are
incorrect.

Note that the expand behavior is *conservatively correct*, and exactly
matches LLVM's current behavior with these operations. Ideally this
patch will not change behavior in any way. For example the regtest suite
finds the exact same instruction sequences coming out of the code
generator. That's why there are no new tests here -- all of this is
being exercised by the existing test suite.

Thanks to Duncan Sands for reviewing the various bits of this patch and
helping me get the wrinkles ironed out with expanding for each target.
Also thanks to Chris for clarifying through all the discussions that
this is indeed the approach he was looking for. That said, there are
likely still rough spots. Further review much appreciated.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146466 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-13 01:56:10 +00:00
Eli Friedman
1c663fee56 Zap unnecessary isIntDivCheap() check. PR11485. No testcase because this doesn't affect any in-tree target.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@146015 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-07 03:55:52 +00:00
Eli Friedman
26323442d5 Fix an optimization involving EXTRACT_SUBVECTOR in DAGCombine so it behaves correctly. PR11494.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145996 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-07 00:11:56 +00:00
Nick Lewycky
8a8d479214 Move global variables in TargetMachine into new TargetOptions class. As an API
change, now you need a TargetOptions object to create a TargetMachine. Clang
patch to follow.

One small functionality change in PTX. PTX had commented out the machine
verifier parts in their copy of printAndVerify. That now calls the version in
LLVMTargetMachine. Users of PTX who need verification disabled should rely on
not passing the command-line flag to enable it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145714 91177308-0d34-0410-b5e6-96231b3b80d8
2011-12-02 22:16:29 +00:00
Evan Cheng
ed1c0c7f58 Revert r145273 and fix in SelectionDAG::InferPtrAlignment() instead.
Conservatively returns zero when the GV does not specify an alignment nor is it
initialized. Previously it returns ABI alignment for type of the GV. However, if
the type is a "packed" type, then the under-specified alignments is attached to
the load / store instructions. In that case, the alignment of the type cannot be
trusted.
rdar://10464621


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145300 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-28 22:37:34 +00:00
Evan Cheng
1c487869f5 DAG combine should not increase alignment of loads / stores with alignment less
than ABI alignment. These are loads / stores from / to "packed" data structures.
Their alignments are intentionally under-specified.

rdar://10301431


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@145273 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-28 20:42:56 +00:00
Eli Friedman
4db4addcd4 Make sure to replace the chain properly when DAGCombining a LOAD+EXTRACT_VECTOR_ELT into a single LOAD. Fixes PR10747/PR11393.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144863 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-16 23:50:22 +00:00
Jay Foad
8c2e35269c Remove some unnecessary includes of PseudoSourceValue.h.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144634 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-15 07:50:46 +00:00
Eli Friedman
501852423d Don't try to form pre/post-indexed loads/stores until after LegalizeDAG runs. Fixes PR11029.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144438 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-12 00:35:34 +00:00
Lang Hames
5207bf2177 Lower mem-ops to unaligned i32/i16 load/stores on ARM where supported.
Add support for trimming constants to GetDemandedBits. This fixes some funky
constant generation that occurs when stores are expanded for targets that don't
support unaligned stores natively.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144102 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-08 18:56:23 +00:00
Pete Cooper
d752e0f7e6 Added invariant field to the DAG.getLoad method and changed all calls.
When this field is true it means that the load is from constant (runt-time or compile-time) and so can be hoisted from loops or moved around other memory accesses


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@144100 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-08 18:42:53 +00:00
Richard Osborne
19a4daff9b Don't introduce custom nodes after legalization in TargetLowering::BuildSDIV()
and TargetLowering::BuildUDIV(). Fixes PR11283


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143964 91177308-0d34-0410-b5e6-96231b3b80d8
2011-11-07 17:09:05 +00:00
Nadav Rotem
f47368bbbe Cleanup. Document. Make sure that this build_vector optimization only runs before the op legalizer and that the used type is legal.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143358 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-31 20:08:25 +00:00
Benjamin Kramer
50bf86ea8a Silence compiler warning.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143308 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-30 08:39:55 +00:00
Nadav Rotem
b00418af67 Add a new DAGCombine optimization for BUILD_VECTOR.
If all of the inputs are zero/any_extended, create a new simple BV
which can be further optimized by other BV optimizations.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143297 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-29 21:23:04 +00:00
Eli Friedman
fd58cd7563 Don't crash on 128-bit sdiv by constant. Found by inspection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@143095 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-27 02:06:39 +00:00
Eli Friedman
9312613137 Remove a couple redundant checks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142959 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-25 20:34:22 +00:00
Bob Wilson
db2b18feba Fix a DAG combiner assertion failure when constant folding BUILD_VECTORS.
svn r139159 caused SelectionDAG::getConstant() to promote BUILD_VECTOR operands
with illegal types, even before type legalization.  For this testcase, that led
to one BUILD_VECTOR with i16 operands and another with promoted i32 operands,
which triggered the assertion.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@142370 91177308-0d34-0410-b5e6-96231b3b80d8
2011-10-18 17:34:47 +00:00
Dan Gohman
7b316c9327 Fix SimplifySelectCC to add newly created nodes to the DAGCombiner
worklist, as it may be possible to perform further optimization on them.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140349 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-22 23:01:29 +00:00
Bruno Cardoso Lopes
e97190fdf8 Add a DAGCombine for subvector extracts to remove useless chains of
subvector inserts and extracts. Initial patch by Rackover, Zvi with
some tweak done by me.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140204 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-20 23:19:33 +00:00
Eli Friedman
9db817fd0c Make the SelectionDAG verify that all the operands of BUILD_VECTOR have the same type. Teach DAGCombiner::visitINSERT_VECTOR_ELT not to make invalid BUILD_VECTORs. Fixes PR10897.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139407 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-09 21:04:06 +00:00
Duncan Sands
28b77e968d Add codegen support for vector select (in the IR this means a select
with a vector condition); such selects become VSELECT codegen nodes.
This patch also removes VSETCC codegen nodes, unifying them with SETCC
nodes (codegen was actually often using SETCC for vector SETCC already).
This ensures that various DAG combiner optimizations kick in for vector
comparisons.  Passes dragonegg bootstrap with no testsuite regressions
(nightly testsuite as well as "make check-all").  Patch mostly by
Nadav Rotem.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@139159 91177308-0d34-0410-b5e6-96231b3b80d8
2011-09-06 19:07:46 +00:00
Benjamin Kramer
deaa64546e Roll back the rest of r126557. It's a hack that will break in some obscure cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@138130 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-19 22:39:31 +00:00
Nadav Rotem
c796ae1d68 Revert r137310 because it does not optimize any code on ToT
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137466 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-12 17:15:04 +00:00
Nadav Rotem
f80a894bf0 [AVX] When joining two XMM registers into a YMM register, make sure that the
lower XMM register gets in first. This will allow the SUBREG pattern to
elliminate the first vector insertion. 



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@137310 91177308-0d34-0410-b5e6-96231b3b80d8
2011-08-11 16:49:36 +00:00
Eli Friedman
ed4b4272ba Make sure this DAGCombine actually returns an UNDEF of the correct type; PR10476.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135993 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-25 22:25:42 +00:00
Chris Lattner
db125cfaf5 land David Blaikie's patch to de-constify Type, with a few tweaks.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135375 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-18 04:54:35 +00:00
Eric Christopher
7332e6ee25 Add a dag combine pattern for folding C2-(A+C1) -> (C2-C1)-A
Fixes rdar://9761830

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@135123 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-14 01:12:15 +00:00
Lang Hames
944520f38c Add functions 'hasPredecessor' and 'hasPredecessorHelper' to SDNode. The
hasPredecessorHelper function allows predecessors to be cached to speed up
repeated invocations. This fixes PR10186.

X.isPredecessorOf(Y) now just calls Y.hasPredecessor(X)

Y.hasPredecessor(X) calls Y.hasPredecessorHelper(X, Visited, Worklist) with
empty Visited and Worklist sets (i.e. no caching over invocations).

Y.hasPredecessorHelper(X, Visited, Worklist) caches search state in Visited
and Worklist to speed up repeated calls. The Visited set is searched for X
before going to the worklist to further search the DAG if necessary.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134592 91177308-0d34-0410-b5e6-96231b3b80d8
2011-07-07 04:31:51 +00:00
Benjamin Kramer
bdd1ef2dbe Revert a part of r126557 which could create unschedulable DAGs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@134067 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-29 13:47:25 +00:00
Jay Foad
267010864e Replace the existing forms of ConstantArray::get() with a single form
that takes an ArrayRef.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133615 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-22 09:24:39 +00:00
Evan Cheng
9568e5c3c3 Teach dag combine to match halfword byteswap patterns.
1. (((x) & 0xFF00) >> 8) | (((x) & 0x00FF) << 8)
   => (bswap x) >> 16
2. ((x&0xff)<<8)|((x&0xff00)>>8)|((x&0xff000000)>>8)|((x&0x00ff0000)<<8))
   => (rotl (bswap x) 16)

This allows us to eliminate most of the def : Pat patterns for ARM rev16
revsh instructions. It catches many more cases for ARM and x86.

rdar://9609108


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133503 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-21 06:01:08 +00:00
Nick Lewycky
c06b5bf340 Add a DAGCombine for (ext (binop (load x), cst)).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133124 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-16 01:15:49 +00:00
Nadav Rotem
baff46f192 Enable the simplification of truncating-store after fixing the usage of
GetDemandBits (which must operate on the vector element type).

Fix the a usage of getZeroExtendInReg which must also be done on scalar types.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133052 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-15 11:19:12 +00:00
Chad Rosier
92bcd96bbc When pattern matching during instruction selection make sure shl x,1 is not
converted to add x,x if x is a undef.  add undef, undef does not guarantee
that the resulting low order bit is zero.
Fixes <rdar://problem/9453156> and <rdar://problem/9487392>.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133022 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-14 22:29:10 +00:00
Nadav Rotem
c7cb7ed013 Disable trunc-store simplification on vectors.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132984 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-14 07:18:26 +00:00
Eli Friedman
2a6d9eb10b Change this DAGCombine to build AND of SHR instead of SHR of AND; this matches the ordering we prefer in instcombine. Part of rdar://9562809.
The potential DAGCombine which enforces this more generally messes up some other very fragile patterns, so I'm leaving that alone, at least for now.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132809 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-09 22:14:44 +00:00
Devang Patel
9728ea2447 Revert 121907 (it causes llc crash) and apply original patch from PR9817.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131926 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-23 22:04:42 +00:00
Benjamin Kramer
f55d26e788 Implement mulo x, 2 -> addo x, x in DAGCombiner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131800 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-21 18:31:55 +00:00
Dan Gohman
71dc7c9d89 Misc. code cleanups.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131495 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-17 22:20:36 +00:00
Nadav Rotem
42febc6e99 Fixes a bug in the DAGCombiner. LoadSDNodes have two values (data, chain).
If there is a store after the load node, then there is a chain, which means
that there is another user. Thus, asking hasOneUser would fail. Instead we
ask hasNUsesOfValue on the 'data' value.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131183 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-11 14:40:50 +00:00
Duncan Sands
c356f33aaf Indent properly, no functionality change.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@131082 91177308-0d34-0410-b5e6-96231b3b80d8
2011-05-09 08:03:33 +00:00
Eli Friedman
e545d38a28 PR9055: extend the fix to PR4050 (r70179) to apply to zext and anyext.
Returning a new node makes the code try to replace the old node, which
in the included testcase is killed by CSE.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129650 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-16 23:25:34 +00:00
Owen Anderson
a34d93630e Fix another instance of the DAG combiner not using the correct type for the RHS of a shift.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129522 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-14 17:30:49 +00:00
Chris Lattner
b3452ea35c have dag combine zap "store undef", which can be formed during call lowering
with undef arguments.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@129185 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-09 02:32:02 +00:00
Cameron Zwarich
ed3caf9086 Add a RemoveFromWorklist method to DCI. This is needed to do some complicated
transformations in target-specific DAG combines without causing DAGCombiner to
delete the same node twice. If you know of a better way to avoid this (see my
next patch for an example), please let me know.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128758 91177308-0d34-0410-b5e6-96231b3b80d8
2011-04-02 02:40:26 +00:00
Evan Cheng
9ef82ce4fe Avoid replacing the value of a directly stored load with the stored value if the load is indexed. rdar://9117613.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@127440 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-11 00:48:56 +00:00
Stuart Hastings
7e33418671 Can't introduce floating-point immediate constants after legalization.
Radar 9056407.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126864 91177308-0d34-0410-b5e6-96231b3b80d8
2011-03-02 19:36:30 +00:00
Nadav Rotem
fcd96199f5 Fix typos in the comments.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126565 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-27 07:40:43 +00:00
Benjamin Kramer
7466678003 Add some DAGCombines for (adde 0, 0, glue), which are useful to optimize legalized code for large integer arithmetic.
1. Inform users of ADDEs with two 0 operands that it never sets carry
2. Fold other ADDs or ADDCs into the ADDE if possible

It would be neat if we could do the same thing for SETCC+ADD eventually, but we can't do that in target independent code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@126557 91177308-0d34-0410-b5e6-96231b3b80d8
2011-02-26 22:48:07 +00:00