Commit Graph

7259 Commits

Author SHA1 Message Date
Artyom Skrobov c736863a85 Two switch blocks in VectorLegalizer::LegalizeOp already have a
default: llvm_unreachable("This action is not supported yet!");

-- so I'm adding one to the third switch block, too.

This is a follow-up fix for http://reviews.llvm.org/D13862

llvm-svn: 250830
2015-10-20 15:06:37 +00:00
Artyom Skrobov 7fd67e25aa Adding support for TargetLoweringBase::LibCall
Summary:
TargetLoweringBase::Expand is defined as "Try to expand this to other ops,
otherwise use a libcall." For ISD::UDIV and ISD::SDIV, the choice between
the two possibilities was defined in a rather convoluted way:

- if DIVREM is legal, expand to DIVREM
- if DIVREM has a custom lowering, expand to DIVREM
- if DIVREM libcall is defined and a remainder from the same division is
  computed elsewhere, expand to a DIVREM libcall
- else, expand to a DIV libcall

This had the undesirable effect that if both DIV and DIVREM are implemented
as libcalls, then ISD::UDIV and ISD::SDIV are expanded to the heavier DIVREM
libcall, even when the remainder isn't used.

The new code adds a new LegalizeAction, TargetLoweringBase::LibCall, so that
backends can directly control whether they prefer an expansion or a conversion
to a libcall. This makes the generic lowering code even more generic,
allowing its reuse in a wider range of target-specific configurations.

The useful effect is that ARM backend will now generate a call
to __aeabi_{i,u}div rather than __aeabi_{i,u}divmod in cases where
it doesn't need the remainder. There's no functional change outside
the ARM backend.

Reviewers: t.p.northover, rengolin

Subscribers: t.p.northover, llvm-commits, aemerson

Differential Revision: http://reviews.llvm.org/D13862

llvm-svn: 250826
2015-10-20 13:14:52 +00:00
Artyom Skrobov b844fa7fc0 Combining DIV+REM->DIVREM doesn't belong in LegalizeDAG; move it over into DAGCombiner.
Summary:
In addition to moving the code over, this patch amends the DIV,REM -> DIVREM
combining to run on all affected nodes at once: if the nodes are converted
to DIVREM one at a time, then the resulting DIVREM may get legalized by the
backend into something target-specific that we won't be able to recognize
and correlate with the remaining nodes.

The motivation is to "prepare terrain" for D13862: when we set DIV and REM
to be legalized to libcalls, instead of the DIVREM, we otherwise lose the
ability to combine them together. To prevent this, we need to take the
DIV,REM -> DIVREM combining out of the lowering stage.

Reviewers: RKSimon, eli.friedman, rengolin

Subscribers: john.brawn, rengolin, llvm-commits

Differential Revision: http://reviews.llvm.org/D13733

llvm-svn: 250825
2015-10-20 13:06:02 +00:00
Owen Anderson faf5187ee0 Restore the original behavior of SelectionDAG::getTargetIndex().
It looks like an extra negation snuck in as apart of restoring it.

llvm-svn: 250726
2015-10-19 19:27:40 +00:00
Benjamin Kramer 2002aadaad Put back SelectionDAG::getTargetIndex.
While technically this is untested dead code, it has out-of-tree users.
This reverts a part of r250434.

llvm-svn: 250717
2015-10-19 18:26:16 +00:00
Simon Pilgrim 04d52d26f6 Use SDValue bool check. NFCI.
llvm-svn: 250653
2015-10-18 12:33:54 +00:00
Simon Pilgrim c2c154e078 Move one-use variable inside test. NFC.
llvm-svn: 250651
2015-10-18 11:47:23 +00:00
Simon Pilgrim 24057b9566 [DAG] Ensure vector constant folding uses correct scalar undef types
Minor fix to D13665 found during post-commit review.

llvm-svn: 250616
2015-10-17 16:49:43 +00:00
Joseph Tremoulet 55b51e9dcc [WinEH] Fix eh.exceptionpointer intrinsic lowering
Summary:
Some shared code for handling eh.exceptionpointer and eh.exceptioncode
needs to not share the part that truncates to 32 bits, which is intended
just for exception codes.

Reviewers: rnk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13747

llvm-svn: 250588
2015-10-17 00:08:08 +00:00
Benjamin Kramer bacc7ba7aa [SelectionDAG] Remove dead code. NFC.
Carefully selected parts without deleting graph stuff and dumping methods.

llvm-svn: 250434
2015-10-15 17:54:06 +00:00
Artyom Skrobov 4bca0bb010 A doccomment for CombineTo, and some NFC refactorings
Summary:
Caching SDLoc(N), instead of recreating it in every single
function call, keeps the code denser, and allows to unwrap long lines.

Reviewers: sunfish, atrick, sdmitrouk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13726

llvm-svn: 250305
2015-10-14 17:18:35 +00:00
Artyom Skrobov a5b9ad22b3 Merge DAGCombiner::visitSREM and DAGCombiner::visitUREM (NFC)
Summary: The two implementations had more code in common than not.

Reviewers: sunfish, MatzeB, sdmitrouk

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13724

llvm-svn: 250302
2015-10-14 16:54:14 +00:00
Duncan P. N. Exon Smith e400a7d412 SelectionDAG: Remove implicit ilist iterator conversions, NFC
llvm-svn: 250214
2015-10-13 19:47:46 +00:00
Matt Arsenault e5d9515fb7 DAGCombiner: Don't stop finding better chain on 2 aliases
The comment says this was stopped because it was unlikely to be
profitable. This is not true if you want to combine vector loads
with multiple components.

For a simple case that looks like

t0 = load t0 ...
t1 = load t0 ...
t2 = load t0 ...
t3 = load t0 ...

t4 = store t0:1, t0:1
  t5 = store t4, t1:0
    t6 = store t5, t2:0
	  t7 = store t6, t3:0

We want to get all of these stores onto a chain
that is a TokenFactor of these N loads. This mostly
solves the AMDGPU merge-stores.ll regressions
with -combiner-alias-analysis for merging vector
stores of vector loads.

llvm-svn: 250138
2015-10-13 00:49:00 +00:00
Matt Arsenault 61dc235f20 DAGCombiner: Combine extract_vector_elt from build_vector
This basic combine was surprisingly missing.
AMDGPU legalizes many operations in terms of 32-bit vector components,
so not doing this results in many extra copies and subregister extracts
that need to be cleaned up later.

InstCombine already does this for the hasOneUse case. The target hook
is to fix a handful of tests which break (e.g. ARM/vmov.ll) which turn
from a vector materialize repeated immediate instruction to a constant
vector load with more scalar copies from it.

llvm-svn: 250129
2015-10-12 23:59:50 +00:00
Cong Hou bf22f5063a Assign correct edge weights to unwind destinations when lowering invoke statement.
When lowering invoke statement, all unwind destinations are directly added as successors of call site block, and the weight of those new edges are not assigned properly. Actually, default weight 16 are used for those edges. This patch calculates the proper edge weights for those edges when collecting all unwind destinations.

Differential revision: http://reviews.llvm.org/D13354

llvm-svn: 250119
2015-10-12 23:02:58 +00:00
Simon Pilgrim c8832fc233 [SelectionDAG] Add common vector constant folding helper function
We have a number of functions that implement constant folding of vectors (unary and binary ops) in near identical manners (and the differences don't appear to be critical).

This patch introduces a common implementation (SelectionDAG::FoldConstantVectorArithmetic) and calls this in both the unary and binary op cases.

After this initial patch I intend to begin enabling vector constant folding for a wider number of opcodes in SelectionDAG::getNode().

Differential Revision: http://reviews.llvm.org/D13665

llvm-svn: 250118
2015-10-12 23:00:11 +00:00
Reid Kleckner 9abb3c06a6 Don't call PrepareEHLandingPad on non EH pads
This was a minor bug in r249492. Calling PrepareEHLandingPad on a
non-landingpad was a no-op, but it attempted to get the generic pointer
register class, which apparently doesn't exist for some targets.

llvm-svn: 250068
2015-10-12 17:42:32 +00:00
David Majnemer 99c1d13e52 [WinEH] Remove CatchObjRecoverIdx
CatchObjRecoverIdx was used for the old scheme, it is no longer
relevant.

llvm-svn: 250065
2015-10-12 16:44:22 +00:00
Oliver Stannard cca893ffac [Debug] Look through bitcasts to find argument registers
On targets where f32 is not legal, we have to look through a BITCAST SDNode to
find the register that an argument is stored in when emitting debug info, or we
will not be able to emit a DW_AT_location for it.

Differential Revision: http://reviews.llvm.org/D13005

llvm-svn: 250056
2015-10-12 15:52:36 +00:00
Simon Pilgrim d45c88bbb5 [DAGCombiner] Improved FMA combine support for vectors
Enabled constant canonicalization for all constants.

Improved combining of constant vectors.

llvm-svn: 249993
2015-10-11 19:48:12 +00:00
Simon Pilgrim 5eac2607b9 [DAGCombiner] Tidyup FMINNUM/FMAXNUM constant folding
Enable constant folding for vector splats as well as scalars.

Enable constant canonicalization for all scalar and vector constants.

llvm-svn: 249978
2015-10-11 16:02:28 +00:00
David Majnemer bfa5b98201 [WinEH] Remove more dead code
wineh-parent is dead, so is ValueOrMBB.

llvm-svn: 249920
2015-10-10 00:04:29 +00:00
Reid Kleckner 14e773500e [WinEH] Delete the old landingpad implementation of Windows EH
The new implementation works at least as well as the old implementation
did.

Also delete the associated preparation tests. They don't exercise
interesting corner cases of the new implementation. All the codegen
tests of the EH tables have already been ported.

llvm-svn: 249918
2015-10-09 23:34:53 +00:00
Reid Kleckner ae44e871cd Revert "Revert "Revert r248959, "[WinEH] Emit int3 after noreturn calls on Win64"""
This reverts commit r249794.

Apparently my checkouts are full of unexpected surprises today.

llvm-svn: 249796
2015-10-09 01:13:17 +00:00
Reid Kleckner b510401785 Revert "Revert r248959, "[WinEH] Emit int3 after noreturn calls on Win64""
This reverts commit r249032.

TODO write commit msg

llvm-svn: 249794
2015-10-09 01:11:37 +00:00
Reid Kleckner ebef256269 [SEH] Fix llvm.eh.exceptioncode fast register allocation assertion
I called the wrong MachineBasicBlock::addLiveIn() overload.

llvm-svn: 249786
2015-10-09 00:15:13 +00:00
Chad Rosier 169865ffda [ARM] Promote helper function to SelectionDAG.
I'll be using the function in a similar combine for AArch64.  The helper was
also improved to handle undef values.

Part of http://reviews.llvm.org/D13442

llvm-svn: 249572
2015-10-07 17:28:58 +00:00
Joseph Tremoulet bde46c5642 [WinEH] Update CoreCLR EH for catchpad MBBs
Summary:
Set the pad MBB as a funclet entry for CoreCLR as well as MSVCCXX, and
update state numbering to put the catchpad block rather than its normal
successor into the unwind map.

Reviewers: majnemer

Subscribers: llvm-commits

Differential Revision: http://reviews.llvm.org/D13492

llvm-svn: 249569
2015-10-07 17:16:25 +00:00
Reid Kleckner 72ba70418f [SEH] Add llvm.eh.exceptioncode intrinsic
This will support the Clang __exception_code intrinsic.

llvm-svn: 249492
2015-10-07 00:27:33 +00:00
David Majnemer 7735a6d07a [WinEH] Create a separate MBB for funclet prologues
Our current emission strategy is to emit the funclet prologue in the
CatchPad's normal destination.  This is problematic because
intra-funclet control flow to the normal destination is not erroneous
and results in us reevaluating the prologue if said control flow is
taken.

Instead, use the CatchPad's location for the funclet prologue.  This
correctly models our desire to have unwind edges evaluate the prologue
but edges to the normal destination result in typical control flow.

Differential Revision: http://reviews.llvm.org/D13424

llvm-svn: 249483
2015-10-06 23:31:59 +00:00
Joseph Tremoulet 7f8c1165cd [WinEH] Implement state numbering for CoreCLR
Summary:
Assign one state number per handler/funclet, tracking parent state,
handler type, and catch type token.
State numbers are arranged such that ancestors have lower state numbers
than their descendants.

Reviewers: majnemer, andrew.w.kaylor, rnk

Subscribers: pgavlin, AndyAyers, llvm-commits

Differential Revision: http://reviews.llvm.org/D13450

llvm-svn: 249457
2015-10-06 20:30:33 +00:00
Joseph Tremoulet 2afea5438f [WinEH] Recognize CoreCLR personality function
Summary:
 - Add CoreCLR to if/else ladders and switches as appropriate.
 - Rename isMSVCEHPersonality to isFuncletEHPersonality to better
   reflect what it captures.

Reviewers: majnemer, andrew.w.kaylor, rnk

Subscribers: pgavlin, AndyAyers, llvm-commits

Differential Revision: http://reviews.llvm.org/D13449

llvm-svn: 249455
2015-10-06 20:28:16 +00:00
David Majnemer 429c8eda22 [SelectionDAGBuilder] Remove dead code
We already check for LandingPadInst two lines above.

llvm-svn: 249280
2015-10-04 18:44:47 +00:00
Simon Pilgrim dde63374c5 [DAGCombiner] Generalize FADD constant combines to work with vectors
Updated the FADD combines to work with vectors as well as scalars.

Differential Revision: http://reviews.llvm.org/D13416

llvm-svn: 249251
2015-10-03 22:06:06 +00:00
Simon Pilgrim a38d76a087 [DAGCombiner] Merge SIGN_EXTEND_INREG vector constant folding methods. NCI.
visitSIGN_EXTEND_INREG calls SelectionDAG::getNode to constant fold scalar constants but handles vector constants itself, despite getNode being capable of dealing with them.

This required a minor change to the getNode implementation to actually deal with cases where the scalars of a BUILD_VECTOR were wider integers than the vector type - which was the only extra ability of the visitSIGN_EXTEND_INREG implementation.

No codegen intended and all existing tests remain the same.

llvm-svn: 249236
2015-10-03 16:26:52 +00:00
David Majnemer f828a0ccc7 [WinEH] Make FuncletLayout more robust against catchret
Catchret transfers control from a catch funclet to an earlier funclet.
However, it is not completely clear which funclet the catchret target is
part of.  Make this clear by stapling the catchret target's funclet
membership onto the CATCHRET SDAG node.

llvm-svn: 249052
2015-10-01 18:44:59 +00:00
NAKAMURA Takumi 096492a07b Reformat.
llvm-svn: 249033
2015-10-01 17:01:03 +00:00
NAKAMURA Takumi 1ed20db720 Revert r248959, "[WinEH] Emit int3 after noreturn calls on Win64"
It broke; LLVM :: CodeGen__Generic__2009-11-16-BadKillsCrash.ll

llvm-svn: 249032
2015-10-01 17:00:56 +00:00
Reid Kleckner 6dec87a8a0 [WinEH] Emit int3 after noreturn calls on Win64
The Win64 unwinder disassembles forwards from each PC to try to
determine if this PC is in an epilogue. If so, it skips calling the EH
personality function for that frame. Typically, this means you cannot
catch an exception in the same frame that you threw it, because 'throw'
calls a noreturn runtime function.

Previously we avoided this problem with the TrapUnreachable
TargetOption, but that's a much bigger hammer than we need. All we need
is a 1 byte non-epilogue instruction right after the call.  Instead,
what we got was an unconditional branch to a shared block containing the
ud2, potentially 7 bytes instead of 1. So, this reverts r206684, which
added TrapUnreachable, and replaces it with something better.

The new code pattern matches for invoke/call followed by unreachable and
inserts an int3 into the DAG. To be 100% watertight, we would need to
insert SEH_Epilogue instructions into all basic blocks ending in a call
with no terminators or successors, but in practice this is unlikely to
come up.

llvm-svn: 248959
2015-09-30 23:09:23 +00:00
Evgeniy Stepanov f608111d1b Fix debug info with SafeStack.
llvm-svn: 248933
2015-09-30 19:55:43 +00:00
David Majnemer a80c151286 [WinEH] Teach AsmPrinter about funclets
Summary:
Funclets have been turned into functions by the time they hit the object
file.  Make sure that they have decent names for the symbol table and
CFI directives explaining how to reason about their prologues.

Differential Revision: http://reviews.llvm.org/D13261

llvm-svn: 248824
2015-09-29 20:12:33 +00:00
Reid Kleckner c71d6275ca [WinEH] Fix ip2state table emission with funclets
Previously we were hijacking the old LandingPadInfo data structures to
communicate our state numbers. Now we don't need that anymore.

llvm-svn: 248763
2015-09-28 23:56:30 +00:00
Hal Finkel bd582581b8 [DAGCombine] Fix getStoreMergeAndAliasCandidates's AA-enabled chain walking
When AA is being used, non-aliasing stores are canonicalized to use the same
chain, and DAGCombiner::getStoreMergeAndAliasCandidates can take advantage of
this by looking only as users of a store's chain operand. However, user
iteration is not result-number specific, we need to check that the use is as a
chain operand, and not via some other operand. It is certainly possible to have
another potentially-aliasing store, which shares the first's base pointer, and
uses the first's chain's node via some other operand.

Failure to catch this situation caused, at least in the included test case, an
assert later because the relative sequence-number ordering caused later
replacement to create a cycle in the DAG.

llvm-svn: 248698
2015-09-28 08:02:14 +00:00
Matthias Braun a3b701f828 SelectionDAGDumper: Print simple operands inline.
Print simple operands inline instead of their pointer/value number.
Simple operands are SDNodes without predecessors like Constant(FP), Register,
UNDEF. This unifies the behaviour with dumpr() which was already doing this.

Previously:
  t0: ch = EntryToken
    t1: i64 = Register %vreg0
  t2: i64,ch = CopyFromReg t0, t1
    t3: i64 = Constant<1>
  t4: i64 = add t2, t3
    t5: i64 = Constant<2>
  t6: i64 = add t2, t5
  t10: i64 = undef
  t11: i8,ch = load t0, t2, t10<LD1[%tmp81]>
  t12: i8,ch = load t0, t4, t10<LD1[%tmp10]>
  t13: i8,ch = load t0, t6, t10<LD1[%tmp12]>

Now:
  t0: ch = EntryToken
  t2: i64,ch = CopyFromReg t0, Register:i64 %vreg0
  t4: i64 = add t2, Constant:i64<1>
  t6: i64 = add t2, Constant:i64<2>
  t11: i8,ch = load<LD1[%tmp81]> t0, t2, undef:i64
  t12: i8,ch = load<LD1[%tmp10]> t0, t4, undef:i64
  t13: i8,ch = load<LD1[%tmp12]> t0, t6, undef:i64

Differential Revision: http://reviews.llvm.org/D12567

llvm-svn: 248628
2015-09-25 22:27:02 +00:00
Matt Arsenault 3c07e963b8 DAGCombiner: Check if store is volatile first
This is the simpler check. NFC.

llvm-svn: 248625
2015-09-25 22:06:19 +00:00
Sanjay Patel bbbf9a1a34 merge vector stores into wider vector stores and fix AArch64 misaligned access TLI hook (PR21711)
This is a redo of D7208 ( r227242 - http://llvm.org/viewvc/llvm-project?view=revision&revision=227242 ).

The patch was reverted because an AArch64 target could infinite loop after the change in DAGCombiner 
to merge vector stores. That happened because AArch64's allowsMisalignedMemoryAccesses() wasn't telling
the truth. It reported all unaligned memory accesses as fast, but then split some 128-bit unaligned
accesses up in performSTORECombine() because they are slow.

This patch attempts to fix the problem in AArch's allowsMisalignedMemoryAccesses() while preserving
existing (perhaps questionable) lowering behavior.

The x86 test shows that store merging is working as intended for a target with fast 32-byte unaligned
stores.

Differential Revision: http://reviews.llvm.org/D12635
 

llvm-svn: 248622
2015-09-25 21:49:48 +00:00
Mohammad Shahid 13f1dfdf2e Codegen: Fix llvm.*absdiff semantic.
Fixes the overflow case of llvm.*absdiff intrinsic also updats the tests and LangRef.rst accordingly.

Differential Revision: http://reviews.llvm.org/D11678

llvm-svn: 248483
2015-09-24 10:35:03 +00:00
Matt Arsenault c721df0478 Use new TokenFactor chain when merging stores
If the stores are storing values from loads which partially
alias the stores, we could end up placing the merged loads
and stores on the same chain which has the potential to break.
Each store may have a different chain dependency on only some
of the original loads. Create a new TokenFactor to capture all
of the required dependencies of the stores rather than assuming
all stores can use the same chain.

The testcase is a situation where this happens, although
it does not have an observable change from this. The DAG nodes
just happened to not be reordered before despite this missing
chain dependency.

This is based on an off-list report for an out of tree target
which regressed due to r246307 and I haven't managed to find a case
where the nodes do end up reordered with an in tree target.

llvm-svn: 248468
2015-09-24 07:22:38 +00:00
Cong Hou 9def6efd7e Fixed an issue on updating profile data when lowering switch statement.
Fixed the issue that when there is an edge from the jump table to the default statement, we should check it directly instead of checking if the sibling of the jump table header is a successor of the jump table header, which may not be the default statment but a successor of it.

llvm-svn: 248354
2015-09-23 00:20:27 +00:00