Commit Graph

7488 Commits

Author SHA1 Message Date
Nirav Dave fa250cad37 Prevent construction of cycle in DAG store merge
When merging stores in DAGCombiner, add check to ensure that no
dependenices exist that would cause the construction of a cycle in our
DAG.  This may happen if one store has a data dependence on another
instruction (e.g. a load) which itself has a (chain) dependence on
another store being merged. These stores cannot be merged safely and
doing so results in a cycle that is discovered in LegalizeDAG.

This test is only done in cases where Antialias analysis is used (UseAA)
as non-AA store merge candidates will be merged logically after all
loads which have been checked to not alias.

Reviewers: ahatanak, spatel, niravd, arsenm, hfinkel, tstellarAMD, jyknight

Subscribers: llvm-commits, tberghammer, danalbert, srhines

Differential Revision: http://reviews.llvm.org/D18336

llvm-svn: 264461
2016-03-25 21:06:30 +00:00
Manman Ren 9dd8c14674 CXX TLS: collect return blocks after SelectAllBasicBlocks.
It is incorrect to get the corresponding MBB for a ReturnInst before
SelectAllBasicBlocks since SelectAllBasicBlocks can change the
correspondence between a ReturnInst and the MBB it is in.

PR27062

llvm-svn: 264358
2016-03-24 23:21:29 +00:00
Sanjoy Das fd3eaa8c5c Reduce code duplication by extracting out a helper function; NFC
llvm-svn: 264355
2016-03-24 22:51:49 +00:00
Sanjoy Das 731c67fed2 Lower varargs correctly in deopt bundle lowering
Earlier we were ignoring varargs in LowerCallSiteWithDeoptBundle because
populateCallLoweringInfo does not set CallLoweringInfo::IsVarArg.

llvm-svn: 264354
2016-03-24 22:37:52 +00:00
Sanjoy Das df9ae70f49 Add lowering support for llvm.experimental.deoptimize
Summary:
Only adds support for "naked" calls to llvm.experimental.deoptimize.
Support for round-tripping through RewriteStatepointsForGC will come
as a separate patch (should be simpler than this one).

Reviewers: reames

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18429

llvm-svn: 264329
2016-03-24 20:23:29 +00:00
Sanjoy Das c0c59fe14e [Statepoints] Fix yet another issue around gc pointer uniqueing
Given that StatepointLowering now uniques derived pointers before
putting them in the per-statepoint spill map, we may end up with missing
entries for derived pointers when we visit a gc.relocate on a pointer
that was de-duplicated away.

Fix this by keeping two maps, one mapping gc pointers to their
de-duplicated values, and one mapping a de-duplicated value to the slot
it is spilled in.

llvm-svn: 264320
2016-03-24 18:57:39 +00:00
Sanjoy Das 42f91a9959 Minor cosmestic changes (NFC)
- Reflow comments
 - Rename function

llvm-svn: 264319
2016-03-24 18:57:31 +00:00
Tim Northover 4498eff9bb CodeGen: extend RHS when splitting ATOMIC_CMP_SWAP_WITH_SUCCESS.
If the operation's type has been promoted during type legalization, we
need to account for the fact that the high bits of the comparison
operand are likely unspecified.

The LHS is usually zero-extended, but MIPS sign extends it, so we have
to be slightly careful.

Patch by Simon Dardis.

llvm-svn: 264296
2016-03-24 15:38:38 +00:00
Pirama Arumuga Nainar dc45aef2d8 Remove unsafe AssertZext after promoting result of FP_TO_FP16
Summary:
Some target lowerings of FP_TO_FP16, for instance ARM's vcvtb.f16.f32
instruction, do not guarantee that the top 16 bits are zeroed out.
Remove the unsafe AssertZext and add tests to exercise this.

Reviewers: jmolloy, sbaranga, kristof.beyls, aadg

Subscribers: llvm-commits, srhines, aemerson

Differential Revision: http://reviews.llvm.org/D18426

llvm-svn: 264285
2016-03-24 14:06:03 +00:00
Justin Bogner c35c10593b SelectionDAG: Remove a tautological dyn_cast. NFC
Index is already a StoreSDNode, so this dyn_cast doesn't do anything.

llvm-svn: 264177
2016-03-23 18:15:33 +00:00
Sanjoy Das a5b2972977 Remove stale comment
llvm-svn: 264131
2016-03-23 02:28:35 +00:00
Sanjoy Das ac53dc7520 [StatepointLowering] Don't do two DenseMap lookups; nfci
llvm-svn: 264130
2016-03-23 02:24:15 +00:00
Sanjoy Das 7edbef316b [StatepointLowering] Minor NFC cleanups
- Use auto
 - Name variables in LLVM style
 - Use llvm::find instead of std::find
 - Blank lines between declarations

llvm-svn: 264129
2016-03-23 02:24:13 +00:00
Sanjoy Das 4cd746ebe0 [StatepointLowering] Minor nfc refactoring
Now that StatepointLoweringInfo represents base pointers, derived
pointers and gc relocates as SmallVectors and not ArrayRefs, we no
longer need to allocate "backing storage" on stack in LowerStatepoint.
So elide the backing storage, and inline the trivial body of
getIncomingStatepointGCValues.

llvm-svn: 264128
2016-03-23 02:24:10 +00:00
Sanjoy Das e58ca59cf4 [StatepointLowering] Schedule gc relocates before uniqueing them
Otherwise we can see an "unexpected" gc.relocate that we uniqued away.

llvm-svn: 264127
2016-03-23 02:24:07 +00:00
Simon Pilgrim c6f5fe3d69 [SelectionDAG] Ensure constant folded legalized vector element types are compatible with the BUILD_VECTOR type
Found during fuzz testing - 32-bit x86 targets were legalizing a <2 x i1> compare result to <2 x i32> when <2 x i64> was expected.

llvm-svn: 264085
2016-03-22 19:59:53 +00:00
Tim Northover b49a8a9dbb CodeGen: check return types match when emitting tail call to builtin.
We were just completely ignoring the types when determining whether we could
safely emit a libcall as a tail call. This is clearly wrong.

Theoretically, we could dig deeper looking for incidental matches (much like
the generic code in Analysis.cpp does), but it's probably not worth it for the
few libcalls that exist.

llvm-svn: 264084
2016-03-22 19:14:38 +00:00
Sanjoy Das eb5037cadc Allow lowering call sites with both funclets and deopt state
Lowering funclets is a no-op, so we can just go ahead and lower the
deopt state.

llvm-svn: 264078
2016-03-22 18:10:39 +00:00
Sanjoy Das 6b535630a1 Add a hasOperandBundlesOtherThan helper, and use it; NFC
llvm-svn: 264072
2016-03-22 17:51:25 +00:00
Simon Pilgrim 25fb4177fb [X86][SSE] Reapplied: Simplify vector LOAD + EXTEND on pre-SSE41 hardware
Improve vector extension of vectors on hardware without dedicated VSEXT/VZEXT instructions.

We already convert these to SIGN_EXTEND_VECTOR_INREG/ZERO_EXTEND_VECTOR_INREG but can further improve this by using the legalizer instead of prematurely splitting into legal vectors in the combine as this only properly helps for lowering to VSEXT/VZEXT.

Removes a lot of unnecessary any_extend + mask pattern - (Fix for PR25718).

Reapplied with a fix for PR26953 (missing vector widening legalization).

Differential Revision: http://reviews.llvm.org/D17932

llvm-svn: 264062
2016-03-22 16:22:08 +00:00
Sanjoy Das 38bfc22161 Add "first class" lowering for deopt operand bundles
Summary:
After this change, deopt operand bundles can be lowered directly by
SelectionDAG into STATEPOINT instructions (which are then lowered to a
call or sequence of nop, with an associated __llvm_stackmaps entry0.
This obviates the need to round-trip deoptimization state through
gc.statepoint via RewriteStatepointsForGC.

Reviewers: reames, atrick, majnemer, JosephTremoulet, pgavlin

Subscribers: sanjoy, mcrosier, majnemer, llvm-commits

Differential Revision: http://reviews.llvm.org/D18257

llvm-svn: 264015
2016-03-22 00:59:13 +00:00
Silviu Baranga 46030585b3 [DAGCombine] Catch the case where extract_vector_elt can cause an any_ext while processing AND SDNodes
Summary:
extract_vector_elt can cause an implicit any_ext if the types don't
match. When processing the following pattern:

  (and (extract_vector_elt (load ([non_ext|any_ext|zero_ext] V))), c)

DAGCombine was ignoring the possible extend, and sometimes removing
the AND even though it was required to maintain some of the bits
in the result to 0, resulting in a miscompile.

This change fixes the issue by limiting the transformation only to
cases where the extract_vector_elt doesn't perform the implicit
extend.

Reviewers: t.p.northover, jmolloy

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D18247

llvm-svn: 263935
2016-03-21 11:43:46 +00:00
Manman Ren 2828c57b6f [CXX_FAST_TLS] fix issues with O0 on ARM, AArch64 and X86.
Since at O0, explicit copies via SplitCSR may not be removed even if
they are unnecessary, we choose not to use SplitCSR at O0.

llvm-svn: 263855
2016-03-18 23:38:49 +00:00
Sanjoy Das 3a02019fbc [SelectionDAG] Remove visitStatepoint; NFC
This way we have a single entry point into StatepointLowering.  The
method was a direct dispatch to LowerStatepoint anyway.

llvm-svn: 263682
2016-03-17 00:47:14 +00:00
Sanjoy Das 43e33d61c6 Fix indentation; NFC
llvm-svn: 263672
2016-03-16 23:11:21 +00:00
Sanjoy Das 70697ff74d Extract out a SelectionDAGBuilder::LowerAsStatepoint; NFC
Summary:
This is a step towards implementing "direct" lowering of calls and
invokes with deopt operand bundles into STATEPOINT nodes (as opposed to
having them mandatorily pass through RewriteStatepointsForGC, which is
the case today).

This change extracts out a `SelectionDAGBuilder::LowerAsStatepoint`
helper function that is able to lower a "statepoint like thing", and
uses it to lower `gc.statepoint` calls.  This is an NFC now, but in a
later change we will use `LowerAsStatepoint` to directly lower calls and
invokes with operand bundles without going through an intermediate
`gc.statepoint` IR representation.

FYI: I expect `SelectionDAGBuilder::StatepointInfo` will evolve as I add
support for lowering non gc.statepoints, right now it is fairly tightly
coupled with an IR level `gc.statepoint`.

Reviewers: reames, pgavlin, JosephTremoulet

Subscribers: sanjoy, mcrosier, llvm-commits

Differential Revision: http://reviews.llvm.org/D18106

llvm-svn: 263671
2016-03-16 23:08:00 +00:00
James Y Knight f44fc5219f Tweak some atomics functions in preparation for larger changes; NFC.
- Rename getATOMIC to getSYNC, as llvm will soon be able to emit both
  '__sync' libcalls and '__atomic' libcalls, and this function is for
  the '__sync' ones.

- getInsertFencesForAtomic() has been replaced with
  shouldInsertFencesForAtomic(Instruction), so that the decision can be
  made per-instruction. This functionality will be used soon.

- emitLeadingFence/emitTrailingFence are no longer called if
  shouldInsertFencesForAtomic returns false, and thus don't need to
  check the condition themselves.

llvm-svn: 263665
2016-03-16 22:12:04 +00:00
Sanjoy Das 19c6159833 [SelectionDAG] Extract out populateCallLoweringInfo; NFC
SelectionDAGBuilder::populateCallLoweringInfo is now used instead of
SelectionDAGBuilder::lowerCallOperands.  The populateCallLoweringInfo
interface is more composable in face of design changes like
http://reviews.llvm.org/D18106

llvm-svn: 263663
2016-03-16 20:49:31 +00:00
Simon Pilgrim b5a20f0fec Removed trailing whitespace
llvm-svn: 263650
2016-03-16 18:37:44 +00:00
Sanjoy Das c11460e051 [StatepointLowering] Move an assertion; NFCI
Instead of running an explicit loop over `gc.relocate` calls hanging off
of a `gc.statepoint`, assert the validity of the type of the value being
relocated in `visitRelocate`.

llvm-svn: 263516
2016-03-15 01:16:31 +00:00
Eric Christopher da8b3f1914 Temporarily Revert "[X86][SSE] Simplify vector LOAD + EXTEND on
pre-SSE41 hardware" as it seems to be causing crashes during code
generation in halide. PR forthcoming.

This reverts commit r263303.

llvm-svn: 263512
2016-03-14 23:59:57 +00:00
Sanjay Patel 7506852709 [DAG] use !isUndef() ; NFCI
llvm-svn: 263453
2016-03-14 18:09:43 +00:00
Sanjay Patel 5719584129 [DAG] use isUndef() ; NFCI
llvm-svn: 263448
2016-03-14 17:28:46 +00:00
Sanjoy Das ecf96c9516 Make gc relocates more strongly typed; NFC
Don't use a `Value *` where we can use a stronger `GCRelocateInst *`
type.

llvm-svn: 263327
2016-03-12 02:54:27 +00:00
Simon Pilgrim 33d57c7547 [X86][SSE] Simplify vector LOAD + EXTEND on pre-SSE41 hardware
Improve vector extension of vectors on hardware without dedicated VSEXT/VZEXT instructions.

We already convert these to SIGN_EXTEND_VECTOR_INREG/ZERO_EXTEND_VECTOR_INREG but can further improve this by using the legalizer instead of prematurely splitting into legal vectors in the combine as this only properly helps for lowering to VSEXT/VZEXT.

Removes a lot of unnecessary any_extend + mask pattern - (Fix for PR25718).

Differential Revision: http://reviews.llvm.org/D17932

llvm-svn: 263303
2016-03-11 22:18:05 +00:00
Simon Pilgrim 61eb49e437 [X86][SSE] Reapplied: Improve vector ZERO_EXTEND by combining to ZERO_EXTEND_VECTOR_INREG
Generalise the existing SIGN_EXTEND to SIGN_EXTEND_VECTOR_INREG combine to support zero extension as well and get rid of a lot of unnecessary ANY_EXTEND + mask patterns.

Reapplied with a fix for PR26870 (avoid premature use of TargetConstant in ZERO_EXTEND_VECTOR_INREG expansion).

Differential Revision: http://reviews.llvm.org/D17691

llvm-svn: 263159
2016-03-10 20:40:26 +00:00
Tom Stellard 9f2e00de7b SelectionDAG: Fix a crash on inline asm when output register supports multiple types
Summary:
The code in SelectionDAG did not handle the case where the
register type and output types were different, but had the same size.

Reviewers: arsenm, echristo

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D17940

llvm-svn: 263022
2016-03-09 16:02:52 +00:00
Hans Wennborg e00b6e7249 Revert r262599 "[X86][SSE] Improve vector ZERO_EXTEND by combining to ZERO_EXTEND_VECTOR_INREG"
This caused PR26870.

llvm-svn: 262935
2016-03-08 16:21:41 +00:00
Justin Bogner 671febc0f7 Re-apply "SelectionDAG: Store SDNode operands in an ArrayRecycler"
This re-applies r262886 with a fix for 32 bit platforms that have 8 byte
pointer alignment, effectively reverting r262892.

Original Message:

  Currently some SDNode operands are malloc'd, some are stored inline in
  subclasses of SDNode, and some are thrown into a BumpPtrAllocator.
  This scheme is complex, inconsistent, and makes refactoring SDNodes
  fairly difficult.

  Instead, we can allocate all of the operands using an ArrayRecycler
  that wraps a BumpPtrAllocator. This keeps the cache locality when
  iterating operands, improves locality when iterating SDNodes without
  looking at operands, and vastly simplifies the ownership semantics.

  It also means we stop overallocating SDNodes by 2-3x and will make it
  simpler to fix the rampant undefined behaviour we have in how we
  mutate SDNodes from one kind to another (See llvm.org/pr26808).

  This is NFC other than the changes in memory behaviour, and I ran some
  LNT tests to make sure this didn't hurt compile time. Not many tests
  changed: there were a couple of 1-2% regressions reported, but there
  were more improvements (of up to 4%) than regressions.

llvm-svn: 262902
2016-03-08 03:14:29 +00:00
Justin Bogner 7e6f09c28f Revert "SelectionDAG: Store SDNode operands in an ArrayRecycler"
Looks like the largest SDNode is different between 32 and 64 bit now,
so this is breaking 32 bit bots. Reverting while I figure out a fix.

This reverts r262886.

llvm-svn: 262892
2016-03-08 01:07:03 +00:00
Justin Bogner 6543a9385f SelectionDAG: Store SDNode operands in an ArrayRecycler
Currently some SDNode operands are malloc'd, some are stored inline in
subclasses of SDNode, and some are thrown into a BumpPtrAllocator.
This scheme is complex, inconsistent, and makes refactoring SDNodes
fairly difficult.

Instead, we can allocate all of the operands using an ArrayRecycler
that wraps a BumpPtrAllocator. This keeps the cache locality when
iterating operands, improves locality when iterating SDNodes without
looking at operands, and vastly simplifies the ownership semantics.

It also means we stop overallocating SDNodes by 2-3x and will make it
simpler to fix the rampant undefined behaviour we have in how we
mutate SDNodes from one kind to another (See llvm.org/pr26808).

This is NFC other than the changes in memory behaviour, and I ran some
LNT tests to make sure this didn't hurt compile time. Not many tests
changed: there were a couple of 1-2% regressions reported, but there
were more improvements (of up to 4%) than regressions.

llvm-svn: 262886
2016-03-08 00:39:51 +00:00
Matt Arsenault ceb2c06cbd DAGCombiner: Check legality before creating extract_vector_elt
Problem not hit by any in tree target.

llvm-svn: 262852
2016-03-07 21:10:09 +00:00
Craig Topper 267bdb2094 [CodeGen] Add space-optimized EmitMergeInputChains1_2 to the DAG isel matching tables. Shaves about 5100 bytes from the X86 matcher table. NFC
llvm-svn: 262815
2016-03-07 07:29:12 +00:00
Michael Kuperstein b89f0fa2a2 [DAGCombine] Fix divrem combine not to assume div/rem type is simple.
The divrem combine assumed the type of the div/rem is simple, which isn't
necessarily true. This probably worked fine until r250825, since it only
saw legal types, but now breaks when it runs as a pre-type-legalization 
combine.

This fixes PR26835.

Differential Revision: http://reviews.llvm.org/D17878

llvm-svn: 262746
2016-03-04 21:23:29 +00:00
Renato Golin 175c6d6d95 [ARM] Merging 64-bit divmod lib calls into one
When div+rem calls on the same arguments are found, the ARM back-end merges the
two calls into one __aeabi_divmod call for up to 32-bits values. However,
for 64-bit values, which also have a lib call (__aeabi_ldivmod), it wasn't
merging the calls, and thus calling ldivmod twice and spilling the temporary
results, which generated pretty bad code.

This patch legalises 64-bit lib calls for divmod, so that now all the spilling
and the second call are gone. It also relaxes the DivRem combiner a bit on the
legal type check, since it was already checking for isLegalOrCustom on every
value, so the extra check for isTypeLegal was redundant.

Second attempt, creating TLI.isOperationCustom like isOperationExpand, to make
sure we only emit valid types or the ones that were explicitly marked as custom.
Now, passing check-all and test-suite on x86, ARM and AArch64.

This patch fixes PR17193 (and a long time FIXME in the tests).

llvm-svn: 262738
2016-03-04 19:19:36 +00:00
Simon Pilgrim 91dd0a796c [X86][SSE] Improve vector ZERO_EXTEND by combining to ZERO_EXTEND_VECTOR_INREG
Generalise the existing SIGN_EXTEND to SIGN_EXTEND_VECTOR_INREG combine to support zero extension as well and get rid of a lot of unnecessary ANY_EXTEND + mask patterns.

Differential Revision: http://reviews.llvm.org/D17691

llvm-svn: 262599
2016-03-03 09:43:28 +00:00
Renato Golin 3d78271eac Revert "[ARM] Merging 64-bit divmod lib calls into one"
This reverts commit r262507, which broke some ARM buildbots.

llvm-svn: 262594
2016-03-03 08:57:44 +00:00
David Majnemer 1ef654024f [X86] Don't give catch objects a displacement of zero
Catch objects with a displacement of zero do not initialize a catch
object.  The displacement is relative to %rsp at the end of the
function's prologue for x86_64 targets.

If we place an object at the top-of-stack, we will end up wit a
displacement of zero resulting in our catch object remaining
uninitialized.

Address this by creating our catch objects as fixed objects.  We will
ensure that the UnwindHelp object is created after the catch objects so
that no catch object will have a displacement of zero.

Differential Revision: http://reviews.llvm.org/D17823

llvm-svn: 262546
2016-03-03 00:01:25 +00:00
Renato Golin 93e42d9934 [ARM] Merging 64-bit divmod lib calls into one
When div+rem calls on the same arguments are found, the ARM back-end merges the
two calls into one __aeabi_divmod call for up to 32-bits values. However,
for 64-bit values, which also have a lib call (__aeabi_ldivmod), it wasn't
merging the calls, and thus calling ldivmod twice and spilling the temporary
results, which generated pretty bad code.

This patch legalises 64-bit lib calls for divmod, so that now all the spilling
and the second call are gone. It also relaxes the DivRem combiner a bit on the
legal type check, since it was already checking for isLegalOrCustom on every
value, so the extra check for isTypeLegal was redundant.

This patch fixes PR17193 (and a long time FIXME in the tests).

llvm-svn: 262507
2016-03-02 19:35:45 +00:00
Justin Bogner b2ecee9c31 SelectionDAG: Use correctly sized allocation functions for SDNodes
The placement new calls here were all calling the allocation function
in RecyclingAllocator/Recycler for SDNode, instead of the function for
the specific subclass we were constructing.

Since this particular allocator always overallocates it more or less
worked, but would hide what we're actually doing from any memory
tools. Also, if you tried to change this allocator so something like a
BumpPtrAllocator or MallocAllocator, the compiler would crash horribly
all the time.

Part of llvm.org/PR26808.

llvm-svn: 262500
2016-03-02 19:01:11 +00:00