The prevents us from trying to convert an i1 predicate vector to a float, or
vice-versa. Better patterns are possible, which will follow in a subsequent
commit. For now we just expand them.
Differential Revision: https://reviews.llvm.org/D65066
llvm-svn: 366931
This adds a DeMorgan combine for OR's of compares to turn them into AND's,
helping prevent them from going into and out of gpr registers. It also fills in
the VCLE and VCLT nodes that MVE can select, allowing it to invert more
compares.
Differential Revision: https://reviews.llvm.org/D65059
llvm-svn: 366920
Much like integers, this adds MVE floating point compares and select. It
requires a lot more buildvector/shuffle code because we may need to expand the
compares without mve.fp, and requires support for and/or because of the way we
lower llvm condition codes.
Some original code by David Sherwood
Differential Revision: https://reviews.llvm.org/D65054
llvm-svn: 366909
This adds support code for building and shuffling i1 predicate registers. It
generally uses two basic principles, either converting the predicate into an
scalar (through a PREDICATE_CAST) and doing scalar operations on it there, or
by converting the register to an full vector register and back.
Some of the code here is a not super efficient but will hopefully cover most
cases of moving i1 vectors around and can be improved in subsequent patches.
Some code by David Sherwood.
Differential Revision: https://reviews.llvm.org/D65052
llvm-svn: 366890
This adds the very basics for MVE vector predication, adding integer VCMP and
VSEL instruction support. This is done through predicate registers (MVT::v16i1,
MVT::v8i1, MVT::v4i1), but otherwise using same mechanics as NEON to custom
lower setcc's through ARMISD::VCXX nodes (VCEQ, VCGT, VCEQZ, etc).
An extra VCNE was added, as this can be handled sensibly by MVE's expanded
number of VCMP condition codes. (There are also VCLE and VCLT which are added
later).
VPSEL is also added here, simply selecting on the vselect.
Original code by David Sherwood.
Differential Revision: https://reviews.llvm.org/D65051
llvm-svn: 366885
While lowering test.set.loop.iterations, it wasn't checked how the
brcond was using the result and so the wls could branch to the loop
preheader instead of not entering it. The same was true for
loop.decrement.reg.
So brcond and br_cc and now lowered manually when using the hwloop
intrinsics. During this we now check whether the result has been
negated and whether we're using SETEQ or SETNE and 0 or 1. We can
then figure out which basic block the WLS and LE should be targeting.
Differential Revision: https://reviews.llvm.org/D64616
llvm-svn: 366809
ARM has code to recognise uses of the "returned" function parameter
attribute which guarantee that the value passed to the function in r0
will be returned in r0 unmodified. IPRA replaces the regmask on call
instructions, so needs to be told about this to avoid reverting the
optimisation.
Differential revision: https://reviews.llvm.org/D64986
llvm-svn: 366669
Summary:
PerformVMOVRRDCombine ommits adding a offset
of 4 to the PointerInfo, when converting a
f64 = load[M]
to
{i32, i32} = {load[M], load[M + 4]}
Which would allow the machine scheduller
to break dependencies with the second load.
- pr42638
Reviewers: eli.friedman, dmgreen, ostannard
Reviewed By: ostannard
Subscribers: ostannard, javed.absar, kristof.beyls, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64870
llvm-svn: 366423
We need to make sure that we are sensibly dealing with vectors of types v2i64
and v2f64, even if most of the time we cannot generate native operations for
them. This mostly adds a lot of testing, plus fixes up a couple of the issues
found. And, or and xor can be legal for v2i64, and shifts combining needs a
slight fixup.
Differential Revision: https://reviews.llvm.org/D64316
llvm-svn: 366106
This adds basic lowering for MVE shifts. There are many shifts in MVE, but the
instructions handled here are:
VSHL (imm)
VSHRu (imm)
VSHRs (imm)
VSHL (vector)
VSHL (register)
MVE, like NEON before it, doesn't have shift right by a vector (or register).
We instead have to negate the amount and shift in the opposite direction. This
means we have to convert any SHR's into a form of SHL (that is still signed or
unsigned) with a negated condition and selecting from there. MVE still does
have shifting by an immediate for SHL, ASR and LSR.
This adds lowering for these and for register forms, which work well for shift
lefts but may require an extra fold of neg(vdup(x)) -> vdup(neg(x)) to potentially
work optimally for right shifts.
Differential Revision: https://reviews.llvm.org/D64212
llvm-svn: 366056
This adjusts the way that we lower NEON shifts to use a DAG target node, not
via a neon intrinsic. This is useful for handling MVE shifts operations in the
same the way. It also renames some of the immediate shift nodes for
consistency, and moves some of the processing of immediate shifts into
LowerShift allowing it to capture more cases.
Differential Revision: https://reviews.llvm.org/D64426
llvm-svn: 366051
The vmovlb instructions can be uses to sign or zero extend vector registers
between types. This adds some patterns for them and relevant testing. The
VBICIMM generation is also put behind a hasNEON check (as is already done for
VORRIMM).
Code originally by David Sherwood.
Differential Revision: https://reviews.llvm.org/D64069
llvm-svn: 366008
This simply makes the MVE integer min and max instructions legal and adds the
relevant patterns for them.
Differential Revision: https://reviews.llvm.org/D64026
llvm-svn: 366004
This adds support for the floor/ceil/trunc/... series of instructions,
converting to various forms of VRINT. They use the same suffixes as their
floating point counterparts. There is not VTINTR, so nearbyint is expanded.
Also added a copysign test, to show it is expanded.
Differential Revision: https://reviews.llvm.org/D63985
llvm-svn: 366003
This adds the patterns for minnm and maxnm from the fminnum and fmaxnum nodes,
similar to scalar types.
Original patch by Simon Tatham
Differential Revision: https://reviews.llvm.org/D63870
llvm-svn: 366002
This patch addresses a couple of problems:
1) The maximum supported offset of LE is -4094.
2) The offset of WLS also needs to be checked, this uses a
maximum positive offset of 4094.
The use of BasicBlockUtils has been changed because the block offsets
weren't being initialised, but the isBBInRange checks both positive
and negative offsets.
ARMISelLowering has been tweaked because the test case presented
another pattern that we weren't supporting.
llvm-svn: 365749
This adds some handling for VMOVimm, using the same method that NEON uses. We
create VMOVIMM/VMVNIMM/VMOVFPIMM nodes based on the immediate, and select them
using the now renamed ARMvmovImm/etc. There is also an extra 64bit immediate
mode that I have not yet added here.
Code by David Sherwood
Differential Revision: https://reviews.llvm.org/D63884
llvm-svn: 365178
The arm condition codes for GE is N==V (and for LT is N!=V). If the source of
flags cannot set V (overflow), such as a cmp against #0, then we can use the
simpler PL and MI conditions that only check N. As these PL/MI conditions are
simpler than GE/LT, other passes like the peephole optimiser can have a better
time optimising away the redundant CMPs.
The exception is the VSEL instruction, which cannot take the PL code, so there
the transform favours GE.
Differential Revision: https://reviews.llvm.org/D64160
llvm-svn: 365117
Summary:
This is the backend part of [[ https://bugs.llvm.org/show_bug.cgi?id=42457 | PR42457 ]].
In middle-end, we'd want to prefer the form with two adds - D63992,
but as this diff shows, not every target will prefer that pattern.
Out of 4 targets for which i added tests all seem to be ok with inc-of-add for scalars,
but only X86 prefer that same pattern for vectors.
Here i'm adding a new TLI hook, always defaulting to the inc-of-add,
but adding AArch64,ARM,PowerPC overrides to prefer inc-of-add only for scalars.
Reviewers: spatel, RKSimon, efriedma, t.p.northover, hfinkel
Reviewed By: efriedma
Subscribers: nemanjai, javed.absar, kristof.beyls, kbarton, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D64090
llvm-svn: 365010
Passing a vector type over the soft-float ABI involves it being split
into four GPRs, so the first thing that has to happen at the start of
the function is to recombine those into a vector register. The ABI
types all vectors as v2f64, so we need to support BUILD_VECTOR for
that type, which I do in this patch by allowing it to be expanded in
terms of INSERT_VECTOR_ELT, and writing an ISel pattern for that in
turn. Similarly, I provide a rule for EXTRACT_VECTOR_ELT so that a
returned vector can be marshalled back into GPRs.
While I'm here, I've also added ISD::UNDEF to the list of operations
we turn back on in `setAllExpand`, because I noticed that otherwise it
gets expanded into a BUILD_VECTOR with explicit zero inputs, leading
to pointless machine instructions to zero out a vector register that's
about to have every lane overwritten of in any case.
Reviewers: dmgreen, ostannard
Subscribers: javed.absar, kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63937
llvm-svn: 364910
If you compile with `-mattr=+mve` (enabling integer MVE instructions
but not floating-point ones), then the scalar FP //registers// exist
and it's legal to move things in and out of them, load and store them,
but it's not legal to do arithmetic on them.
In D60708, the calls to `addRegisterClass` in ARMISelLowering that
enable use of the scalar FP registers became conditionalised on
`Subtarget->hasFPRegs()` instead of `Subtarget->hasVFP2Base()`, so
that loads, stores and moves of those registers would work. But I
didn't realise that that would also enable all the operations on those
types by default.
Now, if the target doesn't have basic VFP, we follow up those
`addRegisterClass` calls by turning back off all the nontrivial
operations you can perform on f32 and f64. That causes several
knock-on failures, which are fixed by allowing the `VMOVDcc` and
`VMOVScc` instructions to be selected even if all you have is
`HasFPRegs`, and adjusting several checks for 'is this a double in a
single-precision-only world?' to the more general 'is this any FP type
we can't do arithmetic on?'. Between those, the whole of the
`float-ops.ll` and `fp16-instructions.ll` tests can now run in
MVE-without-FP mode and generate correct-looking code.
One odd side effect is that I had to relax the check lines in that
test so that they permit test functions like `add_f` to be generated
as tailcalls to software FP library functions, instead of ordinary
calls. Doing that is entirely legal, but the mystery is why this is
the first RUN line that's needed the relaxation: on the usual kind of
non-FP target, no tailcalls ever seem to be generated. Going by the
llc messages, I think `SoftenFloatResult` must be perturbing the code
generation in some way, but that's as much as I can guess.
Reviewers: dmgreen, ostannard
Subscribers: javed.absar, kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D63938
llvm-svn: 364909
Backend changes to enable WLS/LE low-overhead loops for armv8.1-m:
1) Use TTI to communicate to the HardwareLoop pass that we should try
to generate intrinsics that guard the loop entry, as well as setting
the loop trip count.
2) Lower the BRCOND that uses said intrinsic to an Arm specific node:
ARMWLS.
3) ISelDAGToDAG the node to a new pseudo instruction:
t2WhileLoopStart.
4) Add support in ArmLowOverheadLoops to handle the new pseudo
instruction.
Differential Revision: https://reviews.llvm.org/D63816
llvm-svn: 364733
MVE adds the lsll, lsrl and asrl instructions, which perform a shift on a 64 bit value separated into two 32 bit registers.
The Expand64BitShift function is modified to accept ISD::SHL, ISD::SRL and ISD::SRA and convert it into the appropriate opcode in ARMISD. An SHL is converted into an lsll, an SRL is converted into an lsrl for the immediate form and a negation and lsll for the register form, and SRA is converted into an asrl.
test/CodeGen/ARM/shift_parts.ll is added to test the logic of emitting these instructions.
Differential Revision: https://reviews.llvm.org/D63430
llvm-svn: 364654
This adds handling and tests for a number of floating point math routines,
which have no MVE instructions.
Differential Revision: https://reviews.llvm.org/D63725
llvm-svn: 364641
MVE has instructions to widen as it loads, and narrow as it stores. This adds
the required patterns and legalisation to make them work including specifying
that they are legal, patterns to select them and test changes.
Patch by David Sherwood.
Differential Revision: https://reviews.llvm.org/D63839
llvm-svn: 364636
This fills in the gaps for basic MVE loads and stores, allowing unaligned
access and adding far too many tests. These will become important as
narrowing/expanding and pre/post inc are added. Big endian might still not be
handled very well, because we have not yet added bitcasts (and I'm not sure how
we want it to work yet). I've included the alignment code anyway which maps
with our current patterns. We plan to return to that later.
Code written by Simon Tatham, with additional tests from Me and Mikhail Maltsev.
Differential Revision: https://reviews.llvm.org/D63838
llvm-svn: 364633
We don't have vector operations for these, so they need to be expanded for both
integer and float.
Differential Revision: https://reviews.llvm.org/D63595
llvm-svn: 364631
This patch adds necessary shuffle vector and buildvector support for ARM MVE.
It essentially adds support for VDUP, VREVs and some VMOVs, which are often
required by other code (like upcoming patches).
This mostly uses the same code from Neon that already generated
NEONvdup/NEONvduplane/NEONvrev's. These have been renamed to ARMvdup/etc and
moved to ARMInstrInfo as they are common to both architectures. Most of the
selection code seems to be applicable to both, but NEON does have some more
instructions making some parts specific.
Most code originally by David Sherwood.
Differential Revision: https://reviews.llvm.org/D63567
llvm-svn: 364626
The current implementation of ThumbRegisterInfo::saveScavengerRegister
is bad for two reasons: one, it's buggy, and two, it blocks using R12
for other optimizations. So this patch gets rid of it, and adds the
necessary support for using an ordinary emergency spill slot on Thumb1.
(Specifically, I think saveScavengerRegister was broken by r305625, and
nobody noticed for two years because the codepath is almost never used.
The new code will also probably not be used much, but it now has better
tests, and if we fail to emit a necessary emergency spill slot we get a
reasonable error message instead of a miscompile.)
A rough outline of the changes in the patch:
1. Gets rid of ThumbRegisterInfo::saveScavengerRegister.
2. Modifies ARMFrameLowering::determineCalleeSaves to allocate an
emergency spill slot for Thumb1.
3. Implements useFPForScavengingIndex, so the emergency spill slot isn't
placed at a negative offset from FP on Thumb1.
4. Modifies the heuristics for allocating an emergency spill slot to
support Thumb1. This includes fixing ExtraCSSpill so we don't try to
use "lr" as a substitute for allocating an emergency spill slot.
5. Allocates a base pointer in more cases, so the emergency spill slot
is always accessible.
6. Modifies ARMFrameLowering::ResolveFrameIndexReference to compute the
right offset in the new cases where we're forcing a base pointer.
7. Ensures we never generate a load or store with an offset outside of
its frame object. This makes the heuristics more straightforward.
8. Changes Thumb1 prologue and epilogue emission so it never uses
register scavenging.
Some of the changes to the emergency spill slot heuristics in
determineCalleeSaves affect ARM/Thumb2; hopefully, they should allow
the compiler to avoid allocating an emergency spill slot in cases
where it isn't necessary. The rest of the changes should only affect
Thumb1.
Differential Revision: https://reviews.llvm.org/D63677
llvm-svn: 364490
"To" selects an odd-numbered GPR, and "Te" an even one. There are some
8.1-M instructions that have one too few bits in their register fields
and require registers of particular parity, without necessarily using
a consecutive even/odd pair.
Also, the constraint letter "t" should select an MVE q-register, when
MVE is present. This didn't need any source changes, but some extra
tests have been added.
Reviewers: dmgreen, samparker, SjoerdMeijer
Subscribers: javed.absar, eraman, kristof.beyls, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D60709
llvm-svn: 364331
This provides the low-level support to start using MVE vector types in
LLVM IR, loading and storing them, passing them to __asm__ statements
containing hand-written MVE vector instructions, and *if* you have the
hard-float ABI turned on, using them as function parameters.
(In the soft-float ABI, vector types are passed in integer registers,
and combining all those 32-bit integers into a q-reg requires support
for selection DAG nodes like insert_vector_elt and build_vector which
aren't implemented yet for MVE. In fact I've also had to add
`arm_aapcs_vfpcc` to a couple of existing tests to avoid that
problem.)
Specifically, this commit adds support for:
* spills, reloads and register moves for MVE vector registers
* ditto for the VPT predication mask that lives in VPR.P0
* make all the MVE vector types legal in ISel, and provide selection
DAG patterns for BITCAST, LOAD and STORE
* make loads and stores of scalar FP types conditional on
`hasFPRegs()` rather than `hasVFP2Base()`. As a result a few
existing tests needed their llc command lines updating to use
`-mattr=-fpregs` as their method of turning off all hardware FP
support.
Reviewers: dmgreen, samparker, SjoerdMeijer
Subscribers: javed.absar, kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60708
llvm-svn: 364329
If an FP_EXTEND or FP_ROUND isel dag node converts directly between
f16 and f32 when the target CPU has no instruction to do it in one go,
it has to be done in two steps instead, going via f32.
Previously, this was done implicitly, because all such CPUs had the
storage-only implementation of f16 (i.e. the only thing you can do
with one at all is to convert it to/from f32). So isel would legalize
the f16 into an f32 as soon as it saw it, by inserting an fp16_to_fp
node (or vice versa), and then the fp_extend would already be f32->f64
rather than f16->f64.
But that technique can't support a target CPU which has full f16
support but _not_ f64, such as some variants of Arm v8.1-M. So now we
provide custom lowering for FP_EXTEND and FP_ROUND, which checks
support for f16 and f64 and decides on the best thing to do given the
combination of flags it gets back.
Reviewers: dmgreen, samparker, SjoerdMeijer
Subscribers: javed.absar, kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60692
llvm-svn: 364294
As discussed on D62910, we need to check whether particular types of memory access are allowed, not just their alignment/address-space.
This NFC patch adds a MachineMemOperand::Flags argument to allowsMemoryAccess and allowsMisalignedMemoryAccesses, and wires up calls to pass the relevant flags to them.
If people are happy with this approach I can then update X86TargetLowering::allowsMisalignedMemoryAccesses to handle misaligned NT load/stores.
Differential Revision: https://reviews.llvm.org/D63075
llvm-svn: 363179
Types such as float and i64's do not have legal loads in Thumb1, but will still
be loaded with a LDR (or potentially multiple LDR's). As such we can treat the
cost of addressing mode calculations the same as an i32 and get some optimisation
benefits.
Differential Revision: https://reviews.llvm.org/D62968
llvm-svn: 362874
Now with MVE being added, we can add the vector addressing mode costs for it.
These are generally imm7 multiplied by the size of the type being loaded /
stored.
Differential Revision: https://reviews.llvm.org/D62967
llvm-svn: 362873
The fp16 version of VLDR takes a imm8 multiplied by 2. This updates the costs
to account for those, and adds extra testing. It is dependant upon hasFPRegs16
as this is what the load/store instructions require.
Differential Revision: https://reviews.llvm.org/D62966
llvm-svn: 362872
Summary:
- pr42062
When compiling for MinSize,
ARMTargetLowering::LowerCall decides to indirect
multiple calls to a same function. However,
it disconsiders the limitation that thumb1
indirect calls require the callee to be in a
register from r0 to r3 (llvm limiation).
If all those registers are used by arguments, the
compiler dies with "error: run out of registers
during register allocation".
This patch tells the function
IsEligibleForTailCallOptimization if we intend to
perform indirect calls, as to avoid tail call
optimization.
Reviewers: dmgreen, efriedma
Reviewed By: efriedma
Subscribers: javed.absar, kristof.beyls, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62683
llvm-svn: 362366
Those two subtarget features were awkward because their semantics are
reversed: each one indicates the _lack_ of support for something in
the architecture, rather than the presence. As a consequence, you
don't get the behavior you want if you combine two sets of feature
bits.
Each SubtargetFeature for an FP architecture version now comes in four
versions, one for each combination of those options. So you can still
say (for example) '+vfp2' in a feature string and it will mean what
it's always meant, but there's a new string '+vfp2d16sp' meaning the
version without those extra options.
A lot of this change is just mechanically replacing positive checks
for the old features with negative checks for the new ones. But one
more interesting change is that I've rearranged getFPUFeatures() so
that the main FPU feature is appended to the output list *before*
rather than after the features derived from the Restriction field, so
that -fp64 and -d32 can override defaults added by the main feature.
Reviewers: dmgreen, samparker, SjoerdMeijer
Subscribers: srhines, javed.absar, eraman, kristof.beyls, hiraditya, zzheng, Petar.Avramovic, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D60691
llvm-svn: 361845
Details: To make instruction selection really divergence driven it is necessary to assign
the correct register classes to the cross block values beforehand. For the divergent targets
same value type requires different register classes dependent on the value divergence.
Reviewers: rampitec, nhaehnle
Differential Revision: https://reviews.llvm.org/D59990
This commit was reverted because of the build failure.
The reason was mlformed patch.
Build failure fixed.
llvm-svn: 361741
This add patterns for fp16 round and ceil etc. Same as the float and double
patterns.
Differential Revision: https://reviews.llvm.org/D62326
llvm-svn: 361718
Promote a number of fp16 math intrinsics to float, so that the relevant float
math routines can be used. Copysign is expanded so as to be handled in-place.
Differential Revision: https://reviews.llvm.org/D62325
llvm-svn: 361717
Details: To make instruction selection really divergence driven it is necessary to assign
the correct register classes to the cross block values beforehand. For the divergent targets
same value type requires different register classes dependent on the value divergence.
Reviewers: rampitec, nhaehnle
Differential Revision: https://reviews.llvm.org/D59990
llvm-svn: 361644
The new cortex-m schedule in rL360768 helps performance, but can increase the
amount of high-registers used. This, on average, ends up increasing the
codesize by a fair amount (because less instructions are converted from T2 to
T1). On cortex-m at -Oz, where we are quite size-paranoid, it is better to use
the existing DAG scheduler with the RegPressure scheduling preference (at least
until the issues around T2 vs T1 instructions can be improved).
I have also made sure that the Sched::RegPressure dag scheduler is always
chosen for MinSize.
The test shows one case where we increase the number of registers used.
Differential Revision: https://reviews.llvm.org/D61882
llvm-svn: 360769
This generally follows what other targets do. I don't completely
understand why the special case for tail calls existed in the first
place; even when the code was committed in r105413, call lowering didn't
work in the way described in the comments.
Stack protector lowering breaks if the register copies are not glued to
a tail call: we have to insert the stack protector check before the tail
call, and we choose the location based on the assumption that all
physical register dependencies of a tail call are adjacent to the tail
call. (See FindSplitPointForStackProtector.) This is sort of fragile,
but I don't see any reason to break that assumption.
I'm guessing nobody has seen this before just because it's hard to
convince the scheduler to actually schedule the code in a way that
breaks; even without the glue, the only computation that could actually
be scheduled after the register copies is the computation of the call
address, and the scheduler usually prefers to schedule that before the
copies anyway.
Fixes https://bugs.llvm.org/show_bug.cgi?id=41417
Differential Revision: https://reviews.llvm.org/D60427
llvm-svn: 360099
The MachineFunction wasn't used in getOptimalMemOpType, but more importantly,
this allows reuse of findOptimalMemOpLowering that is calling getOptimalMemOpType.
This is the groundwork for the changes in D59766 and D59787, that allows
implementation of TTI::getMemcpyCost.
Differential Revision: https://reviews.llvm.org/D59785
llvm-svn: 359537
This does two main things, firstly adding some at least basic addressing modes
for i64 types, and secondly treats floats and doubles sensibly when there is no
fpu. The floating point change can help codesize in some cases, especially with
D60294.
Most backends seems to not consider the exact VT in isLegalAddressingMode,
instead switching on type size. That is now what this does when the target does
not have an fpu (as the float data will be loaded using LDR's). i64's currently
use the address range of an LDRD (even though they may be legalised and loaded
with an LDR). This is at least better than marking them all as illegal
addressing modes.
I have not attempted to do much with vectors yet. That will need changing once
MVE is added.
Differential Revision: https://reviews.llvm.org/D60677
llvm-svn: 358845
As discussed on PR41359, this patch renames the pair of shift-mask target feature functions to make their purposes more obvious.
shouldFoldShiftPairToMask -> shouldFoldConstantShiftPairToMask
preferShiftsToClearExtremeBits -> shouldFoldMaskToVariableShiftPair
llvm-svn: 358526
There's an existing optimization for x != C, but somehow it was missing
a special case for 0.
While I'm here, also cleaned up the code/comments a bit: the second
value produced by the MERGE_VALUES was actually dead, since a CMOV only
produces one result.
Differential Revision: https://reviews.llvm.org/D59616
llvm-svn: 357437
This should hopefully lead to minor improvements in code generation, and
more accurate spill/reload comments in assembly.
Also fix isLoadFromStackSlotPostFE/isStoreToStackSlotPostFE so they
don't lead to misleading assembly comments for merged memory operands;
this is technically orthogonal, but in practice the relevant memory
operand lists don't show up without this change.
Differential Revision: https://reviews.llvm.org/D59713
llvm-svn: 356963
These changes are related to PR37743 and include:
SelectionDAGBuilder::visitSelect handles the unary SelectPatternFlavor::SPF_ABS case to build ABS node.
Delete the redundant recognizer of the integer ABS pattern from the DAGCombiner.
Add promoting the integer ABS node in the LegalizeIntegerType.
Expand-based legalization of integer result for the ABS nodes.
Expand-based legalization of ABS vector operations.
Add some integer abs testcases for different typesizes for Thumb arch
Add the custom ABS expanding and change the SAD pattern recognizer for X86 arch: The i64 result of the ABS is expanded to:
tmp = (SRA, Hi, 31)
Lo = (UADDO tmp, Lo)
Hi = (XOR tmp, (ADDCARRY tmp, hi, Lo:1))
Lo = (XOR tmp, Lo)
The "detectZextAbsDiff" function is changed for the recognition of pattern with the ABS node. Given a ABS node, detect the following pattern:
(ABS (SUB (ZERO_EXTEND a), (ZERO_EXTEND b))).
Change integer abs testcases for codegen with the ABS node support for AArch64.
Indicate that the ABS is legal for the i64 type when the NEON is supported.
Change the integer abs testcases to show changing of codegen.
Add combine and legalization of ABS nodes for Thumb arch.
Extend 'matchSelectPattern' to recognize the ABS patterns with ICMP_SGE condition.
For discussion, see https://bugs.llvm.org/show_bug.cgi?id=37743
Patch by: @ikulagin (Ivan Kulagin)
Differential Revision: https://reviews.llvm.org/D49837
llvm-svn: 356468
This allows better code size for aarch64 floating point materialization
in a future patch.
Reviewers: evandro
Differential Revision: https://reviews.llvm.org/D58690
llvm-svn: 356389
I am about to introduce some non-power-of-2 width vector MVTs. This
commit fixes a power-of-2 assumption that my forthcoming change would
otherwise break, as shown by test/CodeGen/ARM/vcvt_combine.ll and
vdiv_combine.ll.
Differential Revision: https://reviews.llvm.org/D58927
Change-Id: I56a282e365d3874ab0621e5bdef98a612f702317
llvm-svn: 356341
This uses the infrastructure added in rL353152 to sink zext and sexts to
sub/add users, to enable vsubl/vaddl generation when NEON is available.
See https://bugs.llvm.org/show_bug.cgi?id=40025.
Reviewers: SjoerdMeijer, t.p.northover, samparker, efriedma
Reviewed By: samparker
Differential Revision: https://reviews.llvm.org/D58063
llvm-svn: 355460
When lowering a select_cc node where the true and false values are of type f16,
we can't use a general conditional move because the FP16 instructions do not
support conditional execution. Instead, we must ensure that the condition code
is one of the four supported by the VSEL instruction.
Differential revision: https://reviews.llvm.org/D58813
llvm-svn: 355385
This function was not checking for the condition code variants which are
undefined if either input is NaN, so we were missing selection of the VSEL
instruction in some cases when using -fno-honor-nans or -ffast-math.
Differential revision: https://reviews.llvm.org/D58812
llvm-svn: 355199
Summary:
The description of KnownBits::zext() and
KnownBits::zextOrTrunc() has confusingly been telling
that the operation is equivalent to zero extending the
value we're tracking. That has not been true, instead
the user has been forced to explicitly set the extended
bits as known zero afterwards.
This patch adds a second argument to KnownBits::zext()
and KnownBits::zextOrTrunc() to control if the extended
bits should be considered as known zero or as unknown.
Reviewers: craig.topper, RKSimon
Reviewed By: RKSimon
Subscribers: javed.absar, hiraditya, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D58650
llvm-svn: 355099
In many places in the backend, we like to know whether we're
optimising for code size and this is performed by checking the
current machine function attributes. A subtarget is created on a
per-function basis, so it's possible to know when we're compiling for
code size on construction so record this in the new object.
Differential Revision: https://reviews.llvm.org/D57812
llvm-svn: 353501
This cleans up all GetElementPtr creation in LLVM to explicitly pass a
value type rather than deriving it from the pointer's element-type.
Differential Revision: https://reviews.llvm.org/D57173
llvm-svn: 352913
This broke the RISCV build, and even with that fixed, one of the RISCV
tests behaves surprisingly differently with asserts than without,
leaving there no clear test pattern to use. Generally it seems bad for
hte IR to differ substantially due to asserts (as in, an alloca is used
with asserts that isn't needed without!) and nothing I did simply would
fix it so I'm reverting back to green.
This also required reverting the RISCV build fix in r351782.
llvm-svn: 351796
This patch may seem familiar... but my previous patch handled the
equivalent lsls+and, not this case. Usually instcombine puts the
"and" after the shift, so this case doesn't come up. However, if the
shift comes out of a GEP, it won't get canonicalized by instcombine,
and DAGCombine doesn't have an equivalent transform.
This also modifies isDesirableToCommuteWithShift to suppress DAGCombine
transforms which would make the overall code worse.
I'm not really happy adding a bunch of code to handle this, but it would
probably be tricky to substantially improve the behavior of DAGCombine
here.
Differential Revision: https://reviews.llvm.org/D56032
llvm-svn: 351776
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
This patch adds the sign/zero extension done by
vgetlane to ARM computeKnownBitsForTargetNode.
Differential revision: https://reviews.llvm.org/D56098
llvm-svn: 350553
This saves materializing the immediate. The additional forms are less
common (they don't usually show up for bitfield insert/extract), but
they're still relevant.
I had to add a new target hook to prevent DAGCombine from reversing the
transform. That isn't the only possible way to solve the conflict, but
it seems straightforward enough.
Differential Revision: https://reviews.llvm.org/D55630
llvm-svn: 349857
These features (fairly) recently got split out into their own feature, so we
should make CodeGen use them when available. The main change here is that the
check used to be based on the triple, but now it's based on CPU features.
llvm-svn: 349355
This has two positive effects. First, using a custom node prevents
recombination leading to an infinite loop since the output DAG is notionally a
little more complex than the input one. Using a flag-setting instruction also
allows the subtraction to be folded with the related comparison more easily.
https://reviews.llvm.org/D53190
llvm-svn: 348122
Don't expand SDIV with an immediate that is a power of 2 if we optimise for
minimum code size. For example:
sdiv %1, i32 4
gets expanded to a sequence of 3 instructions, but this is suboptimal for
minimum code size so instead we just generate a MOV and a SDIV if integer
division is supported.
Differential Revision: https://reviews.llvm.org/D54546
llvm-svn: 347965
The lowering was missing live-ins in certain cases, like a sequence of
multiple tMOVCCr_pseudo instructions. This would lead to a verifier
failure, and on pre-v6 Thumb CPSR would be incorrectly clobbered.
For reasons I don't completely understand, it's hard to get a sequence
of multiple tMOVCCr_pseudo instructions; the issue only seems to show up
with 64-bit comparisons where the result is zero-extended. I added some
extra testcases in case that changes in the future. Probably some
optimization opportunities here if anyone is interested. (@test_slt_not
is the case that was getting miscompiled.)
The code to check the liveness of CPSR was stolen from
X86ISelLowering.cpp; maybe it could be refactored into common helper,
but I have no idea where to put it.
Differential Revision: https://reviews.llvm.org/D54192
llvm-svn: 346355
Summary:
Changes all uses of minnan/maxnan to minimum/maximum
globally. These names emphasize that the semantic difference between
these operations is more than just NaN-propagation.
Reviewers: arsenm, aheejin, dschuff, javed.absar
Subscribers: jholewinski, sdardis, wdng, sbc100, jgravelle-google, jrtc27, atanasyan, llvm-commits
Differential Revision: https://reviews.llvm.org/D53112
llvm-svn: 345218
The BKPT instruction is specified to cause a software breakpoint,
and at least on Linux results in a SIGTRAP. This makes it more
suitable for implementing debugtrap than TRAP (aka UDF #254), which
is specified to cause an undefined instruction exception and results
in a SIGILL on Linux.
Moreover, BKPT is not marked as a terminator, which is not only
consistent with the IR instruction but allows the analyzeBlock
function to correctly analyze a basic block containing the instruction,
which fixes an assertion failure in the machine block placement pass
previously triggered by the included test case.
Because BKPT is only supported starting with ARMv5T, we continue to
use UDF #254 when targeting v4T.
Differential Revision: https://reviews.llvm.org/D53614
llvm-svn: 345171
A global alias may use indices which are not considered in bounds. In
such a case, accessing the base object will fail as it only peers
through inbounds accesses. This pattern is used by the swift compiler
to create references to preceeding members in the type metadata. This
would cause the code generation to fail when targeting a platform that
used ELF as the object file format. Be conservative and fail the
read-only check if we run into an alias that we cannot peer through.
llvm-svn: 345107
As I suggested on PR39281, this patch uses PADDL pairwise addition to widen from the vXi8 CTPOP result to the target vector type.
This is a blocker for moving more x86 code to generic vector CTPOP expansion (P32655 + D53258) - ARM's vXi64 CTPOP currently expands, which would generate a vXi64 MUL but ARM's custom lowering expands the general MUL case and vectors aren't well handled in LegalizeDAG - improving the CTPOP lowering was a lot easier than fixing the MUL lowering for this one case......
Differential Revision: https://reviews.llvm.org/D53257
llvm-svn: 344512
Correctly check for relocations in the constant to promote. And don't
allow promoting a constant multiple times.
This partially fixes https://bugs.llvm.org//show_bug.cgi?id=32780 ;
it's not a complete fix because we also need to prevent
ARMConstantIslands from cloning the constant.
(-arm-promote-constant is currently off by default, and it stays off
with this patch. I'll look into turning it on again when all the known
issues are fixed.)
Differential Revision: https://reviews.llvm.org/D51472
llvm-svn: 343361
This mostly affects IR generated by non-clang frontends because clang
generally sets the alignment of globals explicitly.
Fixes https://bugs.llvm.org//show_bug.cgi?id=32394 .
(-arm-promote-constant is currently off by default, and it stays off
with this patch. I'll look into turning it on again when all the known
issues are fixed.)
Differential Revision: https://reviews.llvm.org/D51469
llvm-svn: 343359
This involves changing the shouldExpandAtomicCmpXchgInIR interface, but I have
updated the in-tree backends using this hook (ARM, AArch64, Hexagon) so they
will see no functional change. Previously this hook returned bool, but it now
returns AtomicExpansionKind.
This hook allows targets to select how a given cmpxchg is to be expanded.
D48131 uses this to expand part-word cmpxchg to a target-specific intrinsic.
See my associated RFC for more info on the motivation for this change
<http://lists.llvm.org/pipermail/llvm-dev/2018-June/123993.html>.
Differential Revision: https://reviews.llvm.org/D48130
llvm-svn: 342550
The Technical Reference Manuals for these two CPUs state that branching
to an unaligned 32-bit instruction incurs an extra pipeline reload
penalty. That's bad.
This also enables the optimization at -Os since it costs on average one
byte per loop in return for 1 cycle per iteration, which is pretty good
going.
llvm-svn: 342127
On Windows, if shouldAssumeDSOLocal returns false, it's either a
dllimport reference, or a reference that we should treat as non-local
and create a stub for.
Clean up AArch64Subtarget::ClassifyGlobalReference a little while
touching the flag handling relating to dllimport.
Differential Revision: https://reviews.llvm.org/D51590
llvm-svn: 341402
The runtime pseudo relocations can't handle the ARM format embedded
addresses in movw/movt pairs. By using stubs, the potentially
dllimported addresses can be touched up by the runtime pseudo relocation
framework.
Differential Revision: https://reviews.llvm.org/D51450
llvm-svn: 341176
The inline sequence is very long (about 70 bytes on Thumb1), so it's
not really a good idea to inline it, especially when optimizing for
size.
Differential Revision: https://reviews.llvm.org/D47917
llvm-svn: 340458
This avoids a potential infinite loop setting and unsetting bits in the
mask.
Reduced from a failure on the polly-aosp bot.
Differential Revision: https://reviews.llvm.org/D51066
llvm-svn: 340446
This adds the plumbing for the Tiny code model for the AArch64 backend. This,
instead of loading addresses through the normal ADRP;ADD pair used in the Small
model, uses a single ADR. The 21 bit range of an ADR means that the code and
its statically defined symbols need to be within 1MB of each other.
This makes it mostly interesting for embedded applications where we want to fit
as much as we can in as small a space as possible.
Differential Revision: https://reviews.llvm.org/D49673
llvm-svn: 340397
`MachineMemOperand` pointers attached to `MachineSDNodes` and instead
have the `SelectionDAG` fully manage the memory for this array.
Prior to this change, the memory management was deeply confusing here --
The way the MI was built relied on the `SelectionDAG` allocating memory
for these arrays of pointers using the `MachineFunction`'s allocator so
that the raw pointer to the array could be blindly copied into an
eventual `MachineInstr`. This creates a hard coupling between how
`MachineInstr`s allocate their array of `MachineMemOperand` pointers and
how the `MachineSDNode` does.
This change is motivated in large part by a change I am making to how
`MachineFunction` allocates these pointers, but it seems like a layering
improvement as well.
This would run the risk of increasing allocations overall, but I've
implemented an optimization that should avoid that by storing a single
`MachineMemOperand` pointer directly instead of allocating anything.
This is expected to be a net win because the vast majority of uses of
these only need a single pointer.
As a side-effect, this makes the API for updating a `MachineSDNode` and
a `MachineInstr` reasonably different which seems nice to avoid
unexpected coupling of these two layers. We can map between them, but we
shouldn't be *surprised* at where that occurs. =]
Differential Revision: https://reviews.llvm.org/D50680
llvm-svn: 339740
Intentionally excluding nodes from the DAGCombine worklist is likely to
lead to weird optimizations and infinite loops, so it's generally a bad
idea.
To avoid the infinite loops, fix DAGCombine to use the
isDesirableToCommuteWithShift target hook before performing the
transforms in question, and implement the target hook in the ARM backend
disable the transforms in question.
Fixes https://bugs.llvm.org/show_bug.cgi?id=38530 . (I don't have a
reduced testcase for that bug. But we should have sufficient test
coverage for PerformSHLSimplify given that we're not playing weird
tricks with the worklist. I can try to bugpoint it if necessary,
though.)
Differential Revision: https://reviews.llvm.org/D50667
llvm-svn: 339734
LLVM normally prefers to minimize the number of bits set in an AND
immediate, but that doesn't always match the available ARM instructions.
In Thumb1 mode, prefer uxtb or uxth where possible; otherwise, prefer
a two-instruction sequence movs+ands or movs+bics.
Some potential improvements outlined in
ARMTargetLowering::targetShrinkDemandedConstant, but seems to work
pretty well already.
The ARMISelDAGToDAG fix ensures we don't generate an invalid UBFX
instruction due to a larger-than-expected mask. (It's orthogonal, in
some sense, but as far as I can tell it's either impossible or nearly
impossible to reproduce the bug without this change.)
According to my testing, this seems to consistently improve codesize by
a small amount by forming bic more often for ISD::AND with an immediate.
Differential Revision: https://reviews.llvm.org/D50030
llvm-svn: 339472
Saves materializing the immediate for the "ands".
Corresponding patterns exist for lsrs+lsls, but that seems less common
in practice.
Now implemented as a DAGCombine.
Differential Revision: https://reviews.llvm.org/D49585
llvm-svn: 337945
The original code attempted to do this, but the std::abs() call didn't
actually do anything due to implicit type conversions. Fix the type
conversions, and perform the correct check for negative immediates.
This probably has very little practical impact, but it's worth fixing
just to avoid confusion in the future, I think.
Differential Revision: https://reviews.llvm.org/D48907
llvm-svn: 336742
This patch adds support for the q versions of the dup
(load-to-all-lanes) NEON intrinsics, such as vld2q_dup_f16() for
example.
Currently, non-q versions of the dup intrinsics are implemented
in clang by generating IR that first loads the elements of the
structure into the first lane with the lane (to-single-lane)
intrinsics, and then propagating it other lanes. There are at
least two problems with this approach. First, there are no
double-spaced to-single-lane byte-element instructions. For
example, there is no such instruction as 'vld2.8 { d0[0], d2[0]
}, [r0]'. That means we cannot rely on the to-single-lane
intrinsics and instructions to implement the q versions of the
dup intrinsics. Note that to-all-lanes instructions do support
all sizes of data items, including bytes.
The second problem with the current approach is that we need a
separate vdup instruction to propagate the structure to each
lane. So for vld4q_dup_f16() we would need four vdup instructions
in addition to the initial vld instruction.
This patch introduces dup LLVM intrinsics and reworks handling of
the currently supported (non-q) NEON dup intrinsics to expand
them into those LLVM intrinsics, thus eliminating the need for
using to-single-lane intrinsics and instructions.
Additionally, this patch adds support for u64 and s64 dup NEON
intrinsics. These are marked as Arch64-only in the ARM NEON
Reference, but it seems there are no reasons to not support them
in AArch32 mode. Please correct, if that is wrong.
That's what we generate with this patch applied:
vld2q_dup_f16:
vld2.16 {d0[], d2[]}, [r0]
vld2.16 {d1[], d3[]}, [r0]
vld3q_dup_f16:
vld3.16 {d0[], d2[], d4[]}, [r0]
vld3.16 {d1[], d3[], d5[]}, [r0]
vld4q_dup_f16:
vld4.16 {d0[], d2[], d4[], d6[]}, [r0]
vld4.16 {d1[], d3[], d5[], d7[]}, [r0]
Differential Revision: https://reviews.llvm.org/D48439
llvm-svn: 335733
We currently support them only in AArch64. The NEON Reference,
however, says they are 'ARMv7, ARMv8' intrinsics.
Differential Revision: https://reviews.llvm.org/D47447
llvm-svn: 334361
We currently support them only in AArch64. The NEON Reference,
however, says they are 'ARMv7, ARMv8' intrinsics.
Differential Revision: https://reviews.llvm.org/D47120
llvm-svn: 333825
We currently support them only in AArch64. The NEON Reference,
however, says they are 'ARMv7, ARMv8' intrinsics.
Differential Revision: https://reviews.llvm.org/D47121
llvm-svn: 333819
Summary: This code is now dead as the ARM backend uses ADDCARRY/SUBCARRY/SETCCCARRY .
Reviewers: rogfer01, efriedma, rengolin, javed.absar
Subscribers: kristof.beyls, chrib, llvm-commits
Differential Revision: https://reviews.llvm.org/D47413
llvm-svn: 333544
We've had Thumb1 support for ARMISD::SUBE for a while now, so this just
works. Reduces codesize a bit for 64-bit integer comparisons.
Differential Revision: https://reviews.llvm.org/D47387
llvm-svn: 333445
Chances are we'll be asked again after type legalization, but before that point
it's better to claim misaligned accesses aren't allowed than to assert.
llvm-svn: 332840
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
- Manual change to APInt
- Manually chage DOCS as regex doesn't match it.
In the transition period the DEBUG() macro is still present and aliased
to the LLVM_DEBUG() one.
Differential Revision: https://reviews.llvm.org/D43624
llvm-svn: 332240
Summary: As per title. SETCCE is deprecated and will eventually be removed.
Reviewers: rogfer01, efriedma, rengolin, javed.absar
Subscribers: kristof.beyls, chrib, llvm-commits
Differential Revision: https://reviews.llvm.org/D46512
llvm-svn: 331929
By default LLVM thinks very large vectors get aligned to their size when
passed across functions. Unfortunately no-one told the ARM backend so it
doesn't trigger stack realignment and so accesses can cause the usual
misalignment issues (e.g. a data abort).
This changes the ABI alignment to the stack alignment, which in practice
(and as a bonus) also coincides with the alignment "natural" vectors get.
llvm-svn: 331451
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46290
llvm-svn: 331272
This adds code generation support for the FP16 vmaxnm/vminnm scalar
instructions.
Differential Revision: https://reviews.llvm.org/D44675
llvm-svn: 330034
This is a follow up of rL327695 to instruction select more variants of VSELGT
and VSELGE, for which it is necessary to custom lower SELECT.
More work is required in this area, which will be addressed soon:
- more variants need to be regression tested, but this depends on the next point.
- first LowerConstantFP need to be adjusted for fp16 values.
Differential Revision: https://reviews.llvm.org/D45205
llvm-svn: 329788
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.
The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.
Differential Revision: https://reviews.llvm.org/D45017
llvm-svn: 328806
Follow up patch of r328313 to support the UseVMOVSR constraint. Removed
some unneeded instructions from the test and removed some stray
comments.
Differential Revision: https://reviews.llvm.org/D44941
llvm-svn: 328691
This is used by llvm tblgen as well as by LLVM Targets, so the only
common place is Support for now. (maybe we need another target for these
sorts of things - but for now I'm at least making them correct & we can
make them better if/when people have strong feelings)
llvm-svn: 328395
When targeting execute-only and fp-armv8, float constants in a compare
resulted in instruction selection failures. This is now fixed by using
vmov.f32 where possible, otherwise the floating point constant is
lowered into a integer constant that is moved into a floating point
register.
This patch also restores using fpcmp with immediate 0 under fp-armv8.
Change-Id: Ie87229706f4ed879a0c0cf66631b6047ed6c6443
llvm-svn: 328313
This extends the use of this attribute on ARM and AArch64 from
SVN r325900 (where it was only checked for fixed stack
allocations on ARM/AArch64, but for all stack allocations on X86).
This also adds a testcase for the existing use of disabling the
fixed stack probe with the attribute on ARM and AArch64.
Differential Revision: https://reviews.llvm.org/D44291
llvm-svn: 327897
This is the groundwork for adding the Armv8.2-A FP16 vector intrinsics, which
uses v4f16 and v8f16 vector operands and return values. All the moving parts
are tested with two intrinsics, a 1-operand v8f16 and a 2-operand v4f16
intrinsic. In a follow-up patch the rest of the intrinsics and tests will be
added.
Differential Revision: https://reviews.llvm.org/D44538
llvm-svn: 327839
This implements lowering of SELECT_CC for f16s, which enables
codegen of VSEL with f16 types.
Differential Revision: https://reviews.llvm.org/D44518
llvm-svn: 327695
Emulated TLS is enabled by llc flag -emulated-tls,
which is passed by clang driver.
When llc is called explicitly or from other drivers like LTO,
missing -emulated-tls flag would generate wrong TLS code for targets
that supports only this mode.
Now use useEmulatedTLS() instead of Options.EmulatedTLS to decide whether
emulated TLS code should be generated.
Unit tests are modified to run with and without the -emulated-tls flag.
Differential Revision: https://reviews.llvm.org/D42999
llvm-svn: 326341
Summary:
Expressions of the form x < 0 ? 0 : x; and x < -1 ? -1 : x can be lowered using bit-operations instead of branching or conditional moves
In thumb-mode this results in a two-instruction sequence, a shift followed by a bic or or while in ARM/thumb2 mode that has flexible second operand the shift can be folded into a single bic/or instructions. In most cases this results in smaller code and possibly less branches, and in no case larger than before.
Patch by Martin Svanfeldt
Reviewers: fhahn, pbarrio, rogfer01
Reviewed By: pbarrio, rogfer01
Subscribers: chrib, yroux, eugenis, efriedma, rogfer01, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42574
llvm-svn: 326333
Summary:
Add a target option AllowRegisterRenaming that is used to opt in to
post-register-allocation renaming of registers. This is set to 0 by
default, which causes the hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq
fields of all opcodes to be set to 1, causing
MachineOperand::isRenamable to always return false.
Set the AllowRegisterRenaming flag to 1 for all in-tree targets that
have lit tests that were effected by enabling COPY forwarding in
MachineCopyPropagation (AArch64, AMDGPU, ARM, Hexagon, Mips, PowerPC,
RISCV, Sparc, SystemZ and X86).
Add some more comments describing the semantics of the
MachineOperand::isRenamable function and how it is set and maintained.
Change isRenamable to check the operand's opcode
hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq bit directly instead of
relying on it being consistently reflected in the IsRenamable bit
setting.
Clear the IsRenamable bit when changing an operand's register value.
Remove target code that was clearing the IsRenamable bit when changing
registers/opcodes now that this is done conservatively by default.
Change setting of hasExtraSrcRegAllocReq in AMDGPU target to be done in
one place covering all opcodes that have constant pipe read limit
restrictions.
Reviewers: qcolombet, MatzeB
Subscribers: aemerson, arsenm, jyknight, mcrosier, sdardis, nhaehnle, javed.absar, tpr, arichardson, kristof.beyls, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, escha, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D43042
llvm-svn: 325931
This patch combines some cases of ARMISD::CMOV for integers that arise in comparisons of the form
a != b ? x : 0
a == b ? 0 : x
and that currently (e.g. in Thumb1) are emitted as branches.
Differential Revision: https://reviews.llvm.org/D34515
llvm-svn: 325323
Summary:
In LLVM, 't' selects a floating-point/SIMD register and only supports
32-bit values. This is appropriately documented in the LLVM Language
Reference Manual. However, this behaviour diverges from that of GCC, where
't' selects the s0-s31 registers and its qX and dX variants depending on
additional operand modifiers (q/P).
For example, the following C code:
#include <arm_neon.h>
float32x4_t a, b, x;
asm("vadd.f32 %0, %1, %2" : "=t" (x) : "t" (a), "t" (b))
results in the following assembly if compiled with GCC:
vadd.f32 s0, s0, s1
whereas LLVM will show "error: couldn't allocate output register for
constraint 't'", since a, b, x are 128-bit variables, not 32-bit.
This patch extends the use of 't' to mean that of GCC, thus allowing
selection of the lower Q vector regs and their D/S variants. For example,
the earlier code will now compile as:
vadd.f32 q0, q0, q1
This behaviour still differs from that of GCC but I think it is actually
more correct, since LLVM picks up the right register type based on the
datatype of x, while GCC would need an extra operand modifier to achieve
the same result, as follows:
asm("vadd.f32 %q0, %q1, %q2" : "=t" (x) : "t" (a), "t" (b))
Since this is only an extension of functionality, existing code should not
be affected by this change. Note that operand modifiers q/P are already
supported by LLVM, so this patch should suffice to support inline
assembly with constraint 't' originally built for GCC.
Reviewers: grosbach, rengolin
Reviewed By: rengolin
Subscribers: rogfer01, efriedma, olista01, aemerson, javed.absar, eraman, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42962
llvm-svn: 325244
This adds most of the FP16 codegen support, but these areas need further work:
- FP16 literals and immediates are not properly supported yet (e.g. literal
pool needs work),
- Instructions that are generated from intrinsics (e.g. vabs) haven't been
added.
This will be addressed in follow-up patches.
Differential Revision: https://reviews.llvm.org/D42849
llvm-svn: 324321
Commit r323512 introduced an optimisation in LowerReturn for half-precision
return values. A missing check caused a crash when the return value is "undef"
(i.e. a node that has no operands).
Differential Revision: https://reviews.llvm.org/D42743
llvm-svn: 323968
Summary:
Expressions of the form x < 0 ? 0 : x; and x < -1 ? -1 : x can be lowered using bit-operations instead of branching or conditional moves
In thumb-mode this results in a two-instruction sequence, a shift followed by a bic or or while in ARM/thumb2 mode that has flexible second operand the shift can be folded into a single bic/or instructions. In most cases this results in smaller code and possibly less branches, and in no case larger than before.
Patch by Marten Svanfeldt.
Reviewers: fhahn, pbarrio
Reviewed By: pbarrio
Subscribers: efriedma, rogfer01, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42574
llvm-svn: 323869
Half-precision arguments and return values are passed as if it were an int or
float for ARM. This results in truncates and bitcasts to/from i16 and f16
values, which are legalized very early to stack stores/loads. When FullFP16 is
enabled, we want to avoid codegen for these bitcasts as it is unnecessary and
inefficient.
Differential Revision: https://reviews.llvm.org/D42580
llvm-svn: 323861
This is the groundwork for Armv8.2-A FP16 code generation .
Clang passes and returns _Float16 values as floats, together with the required
bitconverts and truncs etc. to implement correct AAPCS behaviour, see D42318.
We will implement half-precision argument passing/returning lowering in the ARM
backend soon, but for now this means that this:
_Float16 sub(_Float16 a, _Float16 b) {
return a + b;
}
gets lowered to this:
define float @sub(float %a.coerce, float %b.coerce) {
entry:
%0 = bitcast float %a.coerce to i32
%tmp.0.extract.trunc = trunc i32 %0 to i16
%1 = bitcast i16 %tmp.0.extract.trunc to half
<SNIP>
%add = fadd half %1, %3
<SNIP>
}
When FullFP16 is *not* supported, we don't make f16 a legal type, and we get
legalization for "free", i.e. nothing changes and everything works as before.
And also f16 argument passing/returning is handled.
When FullFP16 is supported, we do make f16 a legal type, and have 2 places that
we need to patch up: f16 argument passing and returning, which involves minor
tweaks to avoid unnecessary code generation for some bitcasts.
As a "demonstrator" that this works for the different FP16, FullFP16, softfp
modes, etc., I've added match rules to the VSUB instruction description showing
that we can codegen this instruction from IR, but more importantly, also to
some conversion instructions. These conversions were causing issue before in
the FP16 and FullFP16 cases.
I've also added match rules to the VLDRH and VSTRH desriptions, so that we can
actually compile the entire half-precision sub code example above. This showed
that these loads and stores had the wrong addressing mode specified: AddrMode5
instead of AddrMode5FP16, which turned out not be implemented at all, so that
has also been added.
This is the minimal patch that shows all the different moving parts. In patch
2/3 I will add some efficient lowering of bitcasts, and in 2/3 I will add the
remaining Armv8.2-A FP16 instruction descriptions.
Thanks to Sam Parker and Oliver Stannard for their help and reviews!
Differential Revision: https://reviews.llvm.org/D38315
llvm-svn: 323512
Summary: For long shifts, the inlined version takes about 20 instructions on Thumb1. To avoid the code bloat, expand to __aeabi_ calls if target is Thumb1.
Reviewers: samparker
Reviewed By: samparker
Subscribers: samparker, aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D42401
llvm-svn: 323354
This matches what MSVC does for alloca() function calls on ARM.
Even if MSVC doesn't support VLAs at the language level, it does
support the alloca function.
On the clang level, both the _alloca() (when emulating MSVC, which is
what the alloca() function expands to) and __builtin_alloca() builtin
functions, and VLAs, map to the same LLVM IR "alloca" function - so
within LLVM they're not distinguishable from each other.
Differential Revision: https://reviews.llvm.org/D42292
llvm-svn: 323308
This extends my previous patches to also optimize overflow-checked multiplies during SelectionDAG.
Differential revision: https://reviews.llvm.org/D40922
llvm-svn: 322738
This patch teaches the Arm back-end to generate the SMMULR, SMMLAR and SMMLSR
instructions from equivalent IR patterns.
Differential Revision: https://reviews.llvm.org/D41775
llvm-svn: 322361
The AArch64 backend contains code to optimize {s,u}{add,sub}.with.overflow during SelectionDAG. This commit ports that code to the ARM backend.
Differential revision: https://reviews.llvm.org/D35635
llvm-svn: 321224
Summary:
Implement lower of unsigned saturation on an interval [0, k] where k + 1 is a power of two using USAT instruction in a similar way to how [~k, k] is lowered using SSAT on ARM models that supports it.
Patch by Marten Svanfeldt
Reviewers: t.p.northover, pbarrio, eastig, SjoerdMeijer, javed.absar, fhahn
Reviewed By: fhahn
Subscribers: fhahn, aemerson, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D41348
llvm-svn: 321164
Note:
- X86ISelLowering: setLibcallName(SINCOS) was superfluous as
InitLibcalls() already does it.
- ARMISelLowering: Setting libcallnames for sincos/sincosf seemed
superfluous as in the darwin case it wouldn't be used while for all
other cases InitLibcalls already does it.
llvm-svn: 321036
Rather than adding more bits to express every
MMO flag you could want, just directly use the
MMO flags. Also fixes using a bunch of bool arguments to
getMemIntrinsicNode.
On AMDGPU, buffer and image intrinsics should always
have MODereferencable set, but currently there is no
way to do that directly during the initial intrinsic
lowering.
llvm-svn: 320746
Summary:
Add isRenamable() predicate to MachineOperand. This predicate can be
used by machine passes after register allocation to determine whether it
is safe to rename a given register operand. Register operands that
aren't marked as renamable may be required to be assigned their current
register to satisfy constraints that are not captured by the machine
IR (e.g. ABI or ISA constraints).
Reviewers: qcolombet, MatzeB, hfinkel
Subscribers: nemanjai, mcrosier, javed.absar, llvm-commits
Differential Revision: https://reviews.llvm.org/D39400
llvm-svn: 320503
This is a preparatory step for D34515.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
- fixes PR34564
- fixes PR35103
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 320355
Summary:
The compiler fails with the following error message:
fatal error: error in backend: ran out of registers during
register allocation
Tail call optimization for Armv8-M.base fails to meet all the required
constraints when handling calls to function pointers where the
arguments take up r0-r3. This is because the pointer to the
function to be called can only be stored in r0-r3, but these are
all occupied by arguments. This patch makes sure that tail call
optimization does not try to handle this type of calls.
Reviewers: chill, MatzeB, olista01, rengolin, efriedma
Reviewed By: olista01, efriedma
Subscribers: efriedma, aemerson, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D40706
llvm-svn: 319664
This matches how it is done on X86.
This allows using emulated tls on windows; in MinGW environments,
native tls isn't supported at the moment.
Differential Revision: https://reviews.llvm.org/D40769
llvm-svn: 319643
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).
llvm-svn: 318490
't' constraint normally only accepts f32 operands, but for VCVT the
operands can be i32. LLVM is overly restrictive and rejects asm like:
float foo() {
float result;
__asm__ __volatile__(
"vcvt.f32.s32 %[result], %[arg1]\n"
: [result]"=t"(result)
: [arg1]"t"(0x01020304) );
return result;
}
Relax the value type for 't' constraint to either f32 or i32.
Differential Revision: https://reviews.llvm.org/D40137
llvm-svn: 318472
Summary:
This fixes PR35221.
Use pseudo-instructions to let MachineCSE hoist global address computation.
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits, hiraditya
Differential Revision: https://reviews.llvm.org/D39871
llvm-svn: 318081
When generating table jump code for switch statements, place the jump
table label as the first operand in the various addition instructions
in order to enable addressing mode selectors to better match index
computation and possibly fold them into the addressing mode of the
table entry load instruction.
Differential revision: https://reviews.llvm.org/D39752
llvm-svn: 318033
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.
llvm-svn: 317647
The generic dag combiner will fold:
(shl (add x, c1), c2) -> (add (shl x, c2), c1 << c2)
(shl (or x, c1), c2) -> (or (shl x, c2), c1 << c2)
This can create constants which are too large to use as an immediate.
Many ALU operations are also able of performing the shl, so we can
unfold the transformation to prevent a mov imm instruction from being
generated.
Other patterns, such as b + ((a << 1) | 510), can also be simplified
in the same manner.
Differential Revision: https://reviews.llvm.org/D38084
llvm-svn: 317197
As far as I can tell, this matches gcc: -mfloat-abi determines the
calling convention for all functions except those explicitly defined as
soft-float in the ARM RTABI.
This change only affects cases where the user specifies -mfloat-abi to
override the default calling convention derived from the target triple.
Fixes https://bugs.llvm.org//show_bug.cgi?id=34530.
Differential Revision: https://reviews.llvm.org/D38299
llvm-svn: 316708
Swap the compare operands if the lhs is a shift and the rhs isn't,
as in arm and T2 the shift can be performed by the compare for its
second operand.
Differential Revision: https://reviews.llvm.org/D39004
llvm-svn: 316562
This adds some more debug messages to the type legalizer and functions
like PromoteNode, ExpandNode, ExpandLibCall in an attempt to make
the debug messages a little bit more informative and useful.
Differential Revision: https://reviews.llvm.org/D38450
llvm-svn: 314773
I implemented isTruncateFree in rL313533, this patch fixes the logic
to match my comment, as the previous logic was too general. Now the
only truncates that are free are i64 -> i32.
Differential Revision: https://reviews.llvm.org/D38234
llvm-svn: 314280
This is a preparatory step for D34515.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
- fixes PR34564
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 313618
Implement the isTruncateFree hooks, lifted from AArch64, that are
used by TargetTransformInfo. This allows simplifycfg to reduce the
test case into a single basic block.
Differential Revision: https://reviews.llvm.org/D37516
llvm-svn: 313533
This was causing PR34045 to fire again.
> This is a preparatory step for D34515 and also is being recommitted as its
> first version caused PR34045.
>
> This change:
> - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
> - lowering is done by first converting the boolean value into the carry flag
> using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
> using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
> operations does the actual addition.
> - for subtraction, given that ISD::SUBCARRY second result is actually a
> borrow, we need to invert the value of the second operand and result before
> and after using ARMISD::SUBE. We need to invert the carry result of
> ARMISD::SUBE to preserve the semantics.
> - given that the generic combiner may lower ISD::ADDCARRY and
> ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
> as well otherwise i64 operations now would require branches. This implies
> updating the corresponding test for unsigned.
> - add new combiner to remove the redundant conversions from/to carry flags
> to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
> - fixes PR34045
>
> Differential Revision: https://reviews.llvm.org/D35192
Also revert follow-up r313010:
> [ARM] Fix typo when creating ISD::SUB nodes
>
> In D35192, I accidentally introduced a typo when creating ISD::SUB nodes,
> giving them two values instead of one.
>
> This fails when the merge_values combiner finds one of these nodes.
>
> This change fixes PR34564.
>
> Differential Revision: https://reviews.llvm.org/D37690
llvm-svn: 313044
In D35192, I accidentally introduced a typo when creating ISD::SUB nodes,
giving them two values instead of one.
This fails when the merge_values combiner finds one of these nodes.
This change fixes PR34564.
Differential Revision: https://reviews.llvm.org/D37690
llvm-svn: 313010
This is a preparatory step for D34515 and also is being recommitted as its
first version caused PR34045.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 313009
It caused PR34564.
> This is a preparatory step for D34515 and also is being recommitted as its
> first version caused PR34045.
>
> This change:
> - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
> - lowering is done by first converting the boolean value into the carry flag
> using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
> using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
> operations does the actual addition.
> - for subtraction, given that ISD::SUBCARRY second result is actually a
> borrow, we need to invert the value of the second operand and result before
> and after using ARMISD::SUBE. We need to invert the carry result of
> ARMISD::SUBE to preserve the semantics.
> - given that the generic combiner may lower ISD::ADDCARRY and
> ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
> as well otherwise i64 operations now would require branches. This implies
> updating the corresponding test for unsigned.
> - add new combiner to remove the redundant conversions from/to carry flags
> to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
> - fixes PR34045
>
> Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 312980
This is a preparatory step for D34515 and also is being recommitted as its
first version caused PR34045.
This change:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C
- fixes PR34045
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 312898
ARMTargetLowering::isLegalAddressingMode can accept illegal addressing modes
for the Thumb1 target. This causes generation of redundant code and affects
performance.
This fixes PR34106: https://bugs.llvm.org/show_bug.cgi?id=34106
Differential Revision: https://reviews.llvm.org/D36467
llvm-svn: 311649
The ARM backend should call setBooleanContents so that it can
use known bits to make some optimizations.
Review: D35821
Patch by Joel Galenson <jgalenson@google.com>
llvm-svn: 311446
The calling convention can be specified by the user in IR. Failing to support
a particular calling convention isn't a programming error, and so relying on
llvm_unreachable to catch and report an unsupported calling convention is not
appropriate.
Differential Revision: https://reviews.llvm.org/D36830
llvm-svn: 311435
This is the exact same fix as in SVN r247254. In that commit, the fix was
applied only for isVTRNMask and isVTRN_v_undef_Mask, but the same issue
is present for VZIP/VUZP as well.
This fixes PR33921.
Differential Revision: https://reviews.llvm.org/D36899
llvm-svn: 311258
When lowering a VLA, we emit a __chstk call. However, this call can
internally clobber CPSR. We did not mark this register as an ImpDef,
which could potentially allow a comparison to be hoisted above the call
to `__chkstk`. In such a case, the CPSR could be clobbered, and the
check invalidated. When the support was initially added, it seemed that
the call would take care of preventing CPSR from being clobbered, but
this is not the case. Mark the register as clobbered to fix a possible
state corruption.
llvm-svn: 311061
Summary:
Without the SrcVT its hard to know what is really being asked for. For example if your target has 128, 256, and 512 bit vectors. Maybe extracting 128 from 256 is cheap, but maybe extracting 128 from 512 is not.
For x86 we do support extracting a quarter of a 512-bit register. But for i1 vectors we don't have isel patterns for extracting arbitrary pieces. So we need this to have a correct implementation of isExtractSubvectorCheap for mask vectors.
Reviewers: RKSimon, zvi, efriedma
Reviewed By: RKSimon
Subscribers: aemerson, javed.absar, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D36649
llvm-svn: 310793
The existing code is very clever, but not clear, which seems
like the wrong tradeoff here.
Differential Revision: https://reviews.llvm.org/D36559
llvm-svn: 310653
This patch:
- makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32
- lowering is done by first converting the boolean value into the carry flag
using (_, C) <- (ARMISD::ADDC R, -1) and converted back to an integer value
using (R, _) <- (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two
operations does the actual addition.
- for subtraction, given that ISD::SUBCARRY second result is actually a
borrow, we need to invert the value of the second operand and result before
and after using ARMISD::SUBE. We need to invert the carry result of
ARMISD::SUBE to preserve the semantics.
- given that the generic combiner may lower ISD::ADDCARRY and
ISD::SUBCARRY into ISD::UADDO and ISD::USUBO we need to update their lowering
as well otherwise i64 operations now would require branches. This implies
updating the corresponding test for unsigned.
- add new combiner to remove the redundant conversions from/to carry flags
to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) -> C
Differential Revision: https://reviews.llvm.org/D35192
llvm-svn: 309923
IMHO it is an antipattern to have a enum value that is Default.
At any given piece of code it is not clear if we have to handle
Default or if has already been mapped to a concrete value. In this
case in particular, only the target can do the mapping and it is nice
to make sure it is always done.
This deletes the two default enum values of CodeModel and uses an
explicit Optional<CodeModel> when it is possible that it is
unspecified.
llvm-svn: 309911
Changing mask argument type from const SmallVectorImpl<int>& to
ArrayRef<int>.
This came up in D35700 where a mask is received as an ArrayRef<int> and
we want to pass it to TargetLowering::isShuffleMaskLegal().
Also saves a few lines of code.
llvm-svn: 309085
This patch makes LSR generate better code for SystemZ in the cases of memory
intrinsics, Load->Store pairs or comparison of immediate with memory.
In order to achieve this, the following common code changes were made:
* New TTI hook: LSRWithInstrQueries(), which defaults to false. Controls if
LSR should do instruction-based addressing evaluations by calling
isLegalAddressingMode() with the Instruction pointers.
* In LoopStrengthReduce: handle address operands of memset, memmove and memcpy
as address uses, and call isFoldableMemAccessOffset() for any LSRUse::Address,
not just loads or stores.
SystemZ changes:
* isLSRCostLess() implemented with Insns first, and without ImmCost.
* New function supportedAddressingMode() that is a helper for TTI methods
looking at Instructions passed via pointers.
Review: Ulrich Weigand, Quentin Colombet
https://reviews.llvm.org/D35262https://reviews.llvm.org/D35049
llvm-svn: 308729
OpenCL 2.0 introduces the notion of memory scopes in atomic operations to
global and local memory. These scopes restrict how synchronization is
achieved, which can result in improved performance.
This change extends existing notion of synchronization scopes in LLVM to
support arbitrary scopes expressed as target-specific strings, in addition to
the already defined scopes (single thread, system).
The LLVM IR and MIR syntax for expressing synchronization scopes has changed
to use *syncscope("<scope>")*, where <scope> can be "singlethread" (this
replaces *singlethread* keyword), or a target-specific name. As before, if
the scope is not specified, it defaults to CrossThread/System scope.
Implementation details:
- Mapping from synchronization scope name/string to synchronization scope id
is stored in LLVM context;
- CrossThread/System and SingleThread scopes are pre-defined to efficiently
check for known scopes without comparing strings;
- Synchronization scope names are stored in SYNC_SCOPE_NAMES_BLOCK in
the bitcode.
Differential Revision: https://reviews.llvm.org/D21723
llvm-svn: 307722
r306334 fixed a bug in AArch64 dealing with wide interleaved accesses having
pointer types. The bug also exists in ARM, so this patch copies over the fix.
llvm-svn: 307409
On big-endian machines the high and low parts of the value accessed by ldrexd
and strexd are swapped around. To account for this we swap inputs and outputs
in ISelLowering.
Patch by Bharathi Seshadri.
llvm-svn: 306865
Resubmission of r305387, which was reverted at r305390. The Address
Sanitizer caught a stack-use-after-scope of a Twine variable. This
is now fixed by passing the Twine directly as a function parameter.
The ARM backend asserts against constant pool lowering when it generates
execute-only code in order to prevent the generation of constant pools in
the text section. It appears that target independent optimizations might
generate DAG nodes that represent constant pools. By lowering such nodes
as global addresses we don't violate the semantics of execute-only code
and also it is guaranteed that execute-only behaves correct with the
position-independent addressing modes that support execute-only code.
Differential Revision: https://reviews.llvm.org/D33773
llvm-svn: 305776
This reverts commit 3a204faa093c681a1e96c5e0622f50649b761ee0.
I've upset a buildbot which runs the address sanitizer:
ERROR: AddressSanitizer: stack-use-after-scope
lib/Target/ARM/ARMISelLowering.cpp:2690
That Twine variable is used illegally.
llvm-svn: 305390
The ARM backend asserts against constant pool lowering when it generates
execute-only code in order to prevent the generation of constant pools in
the text section. It appears that target independent optimizations might
generate DAG nodes that represent constant pools. By lowering such nodes
as global addresses we don't violate the semantics of execute-only code
and also it is guaranteed that execute-only behaves correct with the
position-independent addressing modes that support execute-only code.
Differential Revision: https://reviews.llvm.org/D33773
llvm-svn: 305387
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.
I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.
This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.
Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).
llvm-svn: 304787
Summary:
Currently FPOWI defaults to Legal and LegalizeDAG.cpp turns Legal into Expand for this opcode because Legal is a "lie".
This patch changes the default for this opcode to Expand and removes the hack from LegalizeDAG.cpp. It also removes all the code in the targets that set this opcode to Expand themselves since they can just rely on the default.
Reviewers: spatel, RKSimon, efriedma
Reviewed By: RKSimon
Subscribers: jfb, dschuff, sbc100, jgravelle-google, nemanjai, javed.absar, andrew.w.kaylor, llvm-commits
Differential Revision: https://reviews.llvm.org/D33530
llvm-svn: 304215
Currently getOptimalMemOpType returns i32 for large enough sizes without
checking for alignment, leading to poor code generation when misaligned accesses
aren't permitted as we generate a word store then later split it up into byte
stores. This means we inadvertantly go over the MaxStoresPerMemcpy limit and for
memset we splat the memset value into a word then immediately split it up
again.
Fix this by leaving it up to FindOptimalMemOpLowering to figure out which type
to use, but also fix a bug there where it wasn't correctly checking if
misaligned memory accesses are allowed.
Differential Revision: https://reviews.llvm.org/D33442
llvm-svn: 303990
Summary:
A temporary workaround for PR32780 - rematerialized instructions accessing the same promoted global through different constant pool entries.
The patch turns off the globals promotion optimization leaving all its code in place, so that it can be easily turned on once PR32780 is fixed.
Since this is a miscompilation issue causing generation of misbehaving code, and the problem is very subtle, the patch might be valuable enough to get into 4.0.1.
Reviewers: efriedma, jmolloy
Reviewed By: efriedma
Subscribers: aemerson, javed.absar, llvm-commits, rengolin, asl, tstellar
Differential Revision: https://reviews.llvm.org/D33446
llvm-svn: 303679
Use variadic templates instead of relying on <cstdarg> + sentinel.
This enforces better type checking and makes code more readable.
Differential Revision: https://reviews.llvm.org/D32541
llvm-svn: 302571
Now both emitLeadingFence and emitTrailingFence take the instruction
itself, instead of taking IsLoad/IsStore pairs.
Instruction::mayReadFromMemory and Instrucion::mayWriteToMemory are used
for determining those two booleans.
The instruction argument is also useful for later D32763, in
emitTrailingFence. For emitLeadingFence, it seems to have cleaner
interface with the proposed change.
Differential Revision: https://reviews.llvm.org/D32762
llvm-svn: 302539
Using arguments with attribute inalloca creates problems for verification
of machine representation. This attribute instructs the backend that the
argument is prepared in stack prior to CALLSEQ_START..CALLSEQ_END
sequence (see http://llvm.org/docs/InAlloca.htm for details). Frame size
stored in CALLSEQ_START in this case does not count the size of this
argument. However CALLSEQ_END still keeps total frame size, as caller can
be responsible for cleanup of entire frame. So CALLSEQ_START and
CALLSEQ_END keep different frame size and the difference is treated by
MachineVerifier as stack error. Currently there is no way to distinguish
this case from actual errors.
This patch adds additional argument to CALLSEQ_START and its
target-specific counterparts to keep size of stack that is set up prior to
the call frame sequence. This argument allows MachineVerifier to calculate
actual frame size associated with frame setup instruction and correctly
process the case of inalloca arguments.
The changes made by the patch are:
- Frame setup instructions get the second mandatory argument. It
affects all targets that use frame pseudo instructions and touched many
files although the changes are uniform.
- Access to frame properties are implemented using special instructions
rather than calls getOperand(N).getImm(). For X86 and ARM such
replacement was made previously.
- Changes that reflect appearance of additional argument of frame setup
instruction. These involve proper instruction initialization and
methods that access instruction arguments.
- MachineVerifier retrieves frame size using method, which reports sum of
frame parts initialized inside frame instruction pair and outside it.
The patch implements approach proposed by Quentin Colombet in
https://bugs.llvm.org/show_bug.cgi?id=27481#c1.
It fixes 9 tests failed with machine verifier enabled and listed
in PR27481.
Differential Revision: https://reviews.llvm.org/D32394
llvm-svn: 302527
This exposes a method in MachineFrameInfo that calculates
MaxCallFrameSize and calls it after instruction selection in the ARM
target.
This avoids
ARMBaseRegisterInfo::canRealignStack()/ARMFrameLowering::hasReservedCallFrame()
giving different answers in early/late phases of codegen.
The testcase shows a particular nasty example result of that where we
would fail to properly align an alloca.
Differential Revision: https://reviews.llvm.org/D32622
llvm-svn: 302303
This adds routines for reseting KnownBits to unknown, making the value all zeros or all ones. It also adds methods for querying if the value is zero, all ones or unknown.
Differential Revision: https://reviews.llvm.org/D32637
llvm-svn: 302262
Added the integer data processing intrinsics from ACLE v2.1 Chapter 9
but I have missed out the saturation_occurred intrinsics for now. For
the instructions that read and write the GE bits, a chain is included
and the only instruction that reads these flags (sel) is only
selectable via the implemented intrinsic.
Differential Revision: https://reviews.llvm.org/D32281
llvm-svn: 302126
This patch replaces the separate APInts for KnownZero/KnownOne with a single KnownBits struct. This is similar to what was done to ValueTracking's version recently.
This is largely a mechanical transformation from KnownZero to Known.Zero.
Differential Revision: https://reviews.llvm.org/D32569
llvm-svn: 301620
Otherwise there's some mismatch, and we'll either form an illegal type or an
illegal node.
Thanks to Eli Friedman for pointing out the problem with my original solution.
llvm-svn: 301036
DAG combine was mistakenly assuming that the step-up it was looking at was
always a doubling, but it can sometimes be a larger extension in which case
we'd crash.
llvm-svn: 301002
Single-threaded fences aren't required to provide any synchronization with
other processing elements so there's no need for a DMB. They should still be a
barrier for compiler optimizations though.
llvm-svn: 300904
Before, we assumed that any ConstantInt offset was precisely the access width,
so we could use the "[rN]!" form. ISelLowering only ever created that kind, but
further simplification during combining could lead to unexpected constants and
incorrect codegen.
Should fix PR32658.
llvm-svn: 300878
The hardware div feature refers only to Thumb, but because of its name
it is tempting to use it to check for hardware division in general,
which may cause problems in ARM mode. See https://reviews.llvm.org/D32005.
This patch adds "Thumb" to its name, to make its scope clear. One
notable place where I haven't made the change is in the feature flag
(used with -mattr), which is still hwdiv. Changing it would also require
changes in a lot of tests, including clang tests, and it doesn't seem
like it's worth the effort.
Differential Revision: https://reviews.llvm.org/D32160
llvm-svn: 300827
Move the BFI logic to computeKnownBitsForTargetNode, and delete
the redundant CMOV logic.
This is intended as a cleanup, but it's probably possible to construct
a case where moving the BFI logic allows more combines.
Differential Revision: https://reviews.llvm.org/D31795
llvm-svn: 300752
For subtargets that use the custom lowering for divmod, e.g. gnueabi,
we used to check if the subtarget has hardware divide and then lower to
a div-mul-sub sequence if true, or to a libcall if false.
However, judging by the usage of hasDivide vs hasDivideInARMMode, it
seems that hasDivide only refers to Thumb. For instance, in the
ARMTargetLowering constructor, the code that specifies whether to use
libcalls for (S|U)DIV looks like this:
bool hasDivide = Subtarget->isThumb() ? Subtarget->hasDivide()
: Subtarget->hasDivideInARMMode();
In the case of divmod for arm-gnueabi, using only hasDivide() to
determine what to do means that instead of lowering to __aeabi_idivmod
to get the remainder, we lower to div-mul-sub and then further lower the
div to __aeabi_idiv. Even worse, if we have hardware divide in ARM but
not in Thumb, we generate a libcall instead of using it (this is not an
issue in practice since AFAICT none of the cores that we support have
hardware divide in ARM but not Thumb).
This patch fixes the code dealing with custom lowering to take into
account the mode (Thumb or ARM) when deciding whether or not hardware
division is available.
Differential Revision: https://reviews.llvm.org/D32005
llvm-svn: 300536
This patch refactors and strengthens the type checks performed for interleaved
accesses. The primary functional change is to ensure that the interleaved
accesses have valid element types. The added test cases previously failed
because the element type is f128.
Differential Revision: https://reviews.llvm.org/D31817
llvm-svn: 299864
In LowerMUL, the chain information is not preserved for the new
created Load SDNode.
For example, if a Store alias with one of the operand of Mul.
The Load for that operand need to be scheduled before the Store.
The dependence is recorded in the chain of Store, in TokenFactor.
However, when lowering MUL, the SDNodes for the new Loads for
VMULL are not updated in the TokenFactor for the Store. Thus the
chain is not preserved for the lowered VMULL.
llvm-svn: 299701
Follow up to D25691, this sets up the plumbing necessary to support vector demanded elements support in known bits calculations in target nodes.
Differential Revision: https://reviews.llvm.org/D31249
llvm-svn: 299201
Summary:
The true and false operands for the CMOV are operands 0 and 1.
ARMISelLowering.cpp::computeKnownBits was looking at operands 1 and 2
instead. This can cause CMOV instructions to be incorrectly folded into
BFI if value set by the CMOV is another CMOV, whose known bits are
computed incorrectly.
This patch fixes the issue and adds a test case.
Reviewers: kristof.beyls, jmolloy
Subscribers: llvm-commits, aemerson, srhines, rengolin
Differential Revision: https://reviews.llvm.org/D31265
llvm-svn: 298624
including the amended (no UB anymore) fix for adding/subtracting -2147483648.
This reverts r298328 "[ARM] Revert r297443 and r297820."
and partially reverts r297842 "Revert "[Thumb1] Fix the bug when adding/subtracting -2147483648""
llvm-svn: 298417
The glueless lowering of addc/adde in Thumb1 has known serious
miscompiles (see https://reviews.llvm.org/D31081), and r297820
causes an infinite loop for certain constructs. It's not
clear when they will be fixed, so let's just take them out
of the tree for now.
(I resolved a small conflict with r297453.)
llvm-svn: 298328
The special case of zero sized values was previously not handled correctly.
This patch handles this by not promoting if the size is zero.
Patch by Tim Neumann.
Differential Revision: https://reviews.llvm.org/D31116
llvm-svn: 298320
Enable the selection of the 64-bit signed multiply accumulate
instructions which operate on 16-bit operands. These are enabled for
ARMv5TE onwards for ARM and for V6T2 and other DSP enabled Thumb
architectures.
Differential Revision: https://reviews.llvm.org/D30044
llvm-svn: 297809
Create nodes for smulwb and smulwt and move their selection from
DAGToDAG to DAG combine. smlawb and smlawt can then be selected
using tablegen. Added some helper functions to detect shift patterns
as well as a wrapper around SimplifyDemandBits. Added a couple of
extra tests.
Differential Revision: https://reviews.llvm.org/D30708
llvm-svn: 297716
ARMISD::ADD[CE] nodes, instead of the generic ISD::ADD[CE].
Summary:
This allows for some simplification because the combines
are no longer limited to just one go at the node before
it gets legalized into an ARM target-specific one.
Reviewers: jmolloy, rogfer01
Subscribers: aemerson, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D30401
llvm-svn: 297453
same as already done for ARM and Thumb2.
Reviewers: jmolloy, rogfer01, efriedma
Subscribers: aemerson, llvm-commits, rengolin
Differential Revision: https://reviews.llvm.org/D30400
llvm-svn: 297443
The original patch r296865 was reverted as it broke the chromium builds for
Android https://bugs.llvm.org/show_bug.cgi?id=32134, this patch reapplies
r296865 with a fix to make sure it doesn't cause the build regression.
The problem was that intrinsic selection on int_arm_get_fpscr was failing in
ISel this was because the code to manually select this intrinsic still thought
it was the version with no side-effects (INTRINSIC_WO_CHAIN) which is wrong as
it doesn't semantically match the definition in the tablegen code which says it
does have side-effects, I've fixed this by updating the intrinsic type to
INTRINSIC_W_CHAIN (has side-effects). I've also added a test for this based on
Hans original reproducer.
Differential Revision: https://reviews.llvm.org/D30645
llvm-svn: 297137
This patch teaches (ARM|AArch64)ISelLowering.cpp to match illegal vector types
to interleaved access intrinsics as long as the types are multiples of the
vector register width. A "wide" access will now be mapped to multiple
interleave intrinsics similar to the way in which non-interleaved accesses with
illegal types are legalized into multiple accesses. I'll update the associated
TTI costs (in getInterleavedMemoryOpCost) as a follow-on.
Differential Revision: https://reviews.llvm.org/D29466
llvm-svn: 296750
The transform in question claims to be doing:
// fold (add (select cc, 0, c), x) -> (select cc, x, (add, x, c))
...starting in PerformADDCombineWithOperands(), but it wasn't actually checking for a setcc node
for the sext/zext patterns.
This is exactly the opposite of a transform I'd like to add to DAGCombiner's foldSelectOfConstants(),
so I was seeing infinite loops with my draft of a patch applied.
The changes in select_const.ll look positive (less instructions). The change in arm-and-tst-peephole.ll
is unrelated. We're changing the input IR in that test to preserve the intent of the test, but that's
not affected by this code change.
Differential Revision:
https://reviews.llvm.org/D30355
llvm-svn: 296389
Removed the HasT2ExtractPack feature and replaced its references
with HasDSP. This then allows the Thumb2 extend instructions to be
selected for ARMv8M +dsp. These instruction descriptions have also
been refactored and more target tests have been added for their isel.
Differential Revision: https://reviews.llvm.org/D29623
llvm-svn: 295452
When generating a floating point comparison we currently unconditionally
generate VCMPE. This has the sideeffect of setting the cumulative Invalid
bit in FPSCR if any of the operands are QNaN.
It is expected that use of a relational predicate on a QNaN value should
raise Invalid. Quoting from the C standard:
The relational and equality operators support the usual mathematical
relationships between numeric values. For any ordered pair of numeric
values exactly one of relationships the less, greater, equal and is true.
Relational operators may raise the floating-point exception when argument
values are NaNs.
The standard doesn't explicitly state the expectation for equality operators,
but the implication and obvious expectation is that equality operators
should not raise Invalid on a QNaN input, as those predicates are wholly
defined on unordered inputs (to return not equal).
Therefore, add a new operand to ARMISD::FPCMP and FPCMPZ indicating if
QNaN should raise Invalid, and pipe that through to TableGen.
llvm-svn: 294945
There are no vldN/vstN f16 variants, even with +fullfp16.
We could use the i16 variants, but, in practice, even with +fullfp16,
the f16 sequence leading to the i16 shuffle usually gets scalarized.
We'd need to improve our support for f16 codegen before getting there.
Reject f16 interleaved accesses. If we try to emit the f16 intrinsics,
we'll just end up with a selection failure.
llvm-svn: 294818
We mark X0 as preserved by a call that passes the returned parameter.
x0 = ...
fun(x0) // no implicit def of x0
This no longer is valid if we pass the parameter in a different register then
the returned value as is the case with a swiftself parameter (passed in x20).
x20 = ...
fun(x20) // there should be an implict def of x8
rdar://30425845
llvm-svn: 294527
When constructing global address literals while targeting the RWPI
relocation model. LLVM currently only uses literal pools. If MOVW/MOVT
instructions are available we can use these instead. Beside being more
efficient it allows -arm-execute-only to work with
-relocation-model=RWPI as well.
When we generate MOVW/MOVT for global addresses when targeting the RWPI
relocation model, we need to use base relative relocations. This patch
does the needed plumbing in MC to generate these for MOVW/MOVT.
Differential Revision: https://reviews.llvm.org/D29487
Change-Id: I446786e43a6f5aa9b6a5bb2cd216d60d41c7755d
llvm-svn: 294298
This patch moves some helper functions related to interleaved access
vectorization out of LoopVectorize.cpp and into VectorUtils.cpp. We would like
to use these functions in a follow-on patch that improves interleaved load and
store lowering in (ARM/AArch64)ISelLowering.cpp. One of the functions was
already duplicated there and has been removed.
Differential Revision: https://reviews.llvm.org/D29398
llvm-svn: 293788
We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html
For reference:
- Public headers should just declare the dump() method but not use
LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
LLVM_DUMP_METHOD void MyClass::dump() {
// print stuff to dbgs()...
}
#endif
llvm-svn: 293359
The Windows on ARM target uses custom division for normal division as
the backend needs to insert division-by-zero checks. However, it is
designed to only handle non-vectorized division. ARM has custom
lowering for vectorized division as that can avoid loading registers
with the values and invoke a division routine for each one, preferring
to lower using NEON instructions. Fall back to the custom lowering for
the NEON instructions if we encounter a vectorized division.
Resolves PR31778!
llvm-svn: 293259
Hunt down some of the places where we use bare addReg(0) or addImm(AL).addReg(0)
and replace with add(condCodeOp()) and add(predOps()). This should make it
easier to understand what those operands represent (without having to look at
the definition of the instruction that we're adding to).
Differential Revision: https://reviews.llvm.org/D27984
llvm-svn: 292587
GCC changes the CC between the user-code and the builtins based on the
value of `-target` rather than `-mfloat-abi`. When a HF target is used,
the VFP variant of the AAPCS CC is used. Otherwise, the AAPCS variant
is used. In all cases, the AEABI functions use the AAPCS CC. Adjust
the calling convention based on the target.
Resolves PR30543!
llvm-svn: 291909
For AddDefaultT1CC, we add a new helper t1CondCodeOp, which creates the
appropriate register operand. For AddNoT1CC, we use the existing condCodeOp
helper - we only had two uses of AddNoT1CC, so at this point it's probably not
worth having yet another helper just for them.
Differential Revision: https://reviews.llvm.org/D28603
llvm-svn: 291894
Replace all uses of AddDefaultCC with add(condCodeOp()).
The transformation has been done automatically with a custom tool based on Clang
AST Matchers + RefactoringTool.
Differential Revision: https://reviews.llvm.org/D28557
llvm-svn: 291893
Rename from addOperand to just add, to match the other method that has been
added to MachineInstrBuilder for adding more than just 1 operand.
See https://reviews.llvm.org/D28057 for the whole discussion.
Differential Revision: https://reviews.llvm.org/D28556
llvm-svn: 291891
Replace all uses of AddDefaultPred with MachineInstrBuilder::add(predOps()).
This makes the code building MachineInstrs more readable, because it allows us
to write code like:
MIB.addSomeOperand(blah)
.add(predOps())
.addAnotherOperand(blahblah)
instead of
AddDefaultPred(MIB.addSomeOperand(blah))
.addAnotherOperand(blahblah)
This commit also adds the predOps helper in the ARM backend, as well as the add
method taking a variable number of operands to the MachineInstrBuilder.
The transformation has been done mostly automatically with a custom tool based
on Clang AST Matchers + RefactoringTool.
Differential Revision: https://reviews.llvm.org/D28555
llvm-svn: 291890
Switch some additional library call setup to be table driven. This
makes it more immediately obvious what the library call looks like.
This is important for ARM since the calling conventions for the builtins
change based on the target/libcall name. NFC
llvm-svn: 291789
The new matchers work after legalization to make them simpler, and to avoid
blocking other optimizations.
Differential Revision: https://reviews.llvm.org/D27779
llvm-svn: 291693
See https://reviews.llvm.org/D6678 for the history of
isExtractSubvectorCheap. Essentially the same considerations apply
to ARM.
This temporarily breaks the formation of vpadd/vpaddl in certain cases;
AddCombineToVPADDL essentially assumes that we won't form VUZP shuffles.
See https://reviews.llvm.org/D27779 for followup fix.
Differential Revision: https://reviews.llvm.org/D27774
llvm-svn: 290198
Currently, there are substantial problems forming vld1_dup even if the
VDUP survives legalization. The lack of an actual node
leads to terrible results: not only can we not form post-increment vld1_dup
instructions, but we form scalar pre-increment and post-increment
loads which force the loaded value into a GPR. This patch fixes that
by combining the vdup+load into an ARMISD node before DAGCombine
messes it up.
Also includes a crash fix for vld2_dup (see testcase @vld2dupi8_postinc_variable).
Recommiting with fix to avoid forming vld1dup if the type of the load
doesn't match the type of the vdup (see
https://llvm.org/bugs/show_bug.cgi?id=31404).
Differential Revision: https://reviews.llvm.org/D27694
llvm-svn: 289972
Add two public methods to ARMTargetLowering: CCAssignFnForCall and
CCAssignFnForReturn, which are just calling the already existing private method
CCAssignFnForNode. These will come in handy for GlobalISel on ARM.
We also replace all calls to CCAssignFnForNode in ARMISelLowering.cpp, because
the new methods are friendlier to the reader.
llvm-svn: 289932
This implements execute-only support for ARM code generation, which
prevents the compiler from generating data accesses to code sections.
The following changes are involved:
* Add the CodeGen option "-arm-execute-only" to the ARM code generator.
* Add the clang flag "-mexecute-only" as well as the GCC-compatible
alias "-mpure-code" to enable this option.
* When enabled, literal pools are replaced with MOVW/MOVT instructions,
with VMOV used in addition for floating-point literals. As the MOVT
instruction is required, execute-only support is only available in
Thumb mode for targets supporting ARMv8-M baseline or Thumb2.
* Jump tables are placed in data sections when in execute-only mode.
* The execute-only text section is assigned section ID 0, and is
marked as unreadable with the SHF_ARM_PURECODE flag with symbol 'y'.
This also overrides selection of ELF sections for globals.
llvm-svn: 289784
Given that INSERT_VECTOR_ELT operates on D registers anyway, combining
64-bit vectors into a 128-bit vector is basically free. Therefore, try
to split BUILD_VECTOR nodes before giving up and lowering them to a series
of INSERT_VECTOR_ELT instructions. Sometimes this allows dramatically
better lowerings; see testcases for examples. Inspired by similar code
in the x86 backend for AVX.
Differential Revision: https://reviews.llvm.org/D27624
llvm-svn: 289706
Currently, there are substantial problems forming vld1_dup even if the
VDUP survives legalization. The lack of an actual node
leads to terrible results: not only can we not form post-increment vld1_dup
instructions, but we form scalar pre-increment and post-increment
loads which force the loaded value into a GPR. This patch fixes that
by combining the vdup+load into an ARMISD node before DAGCombine
messes it up.
Also includes a crash fix for vld2_dup (see testcase @vld2dupi8_postinc_variable).
Differential Revision: https://reviews.llvm.org/D27694
llvm-svn: 289703
Summary:
This patch aims to generalize matching of the strided store accesses to more general masks.
The more general rule is to have consecutive accesses based on the stride:
[x, y, ... z, x+1, y+1, ...z+1, x+2, y+2, ...z+2, ...]
All elements in the masks need not form a contiguous space, there may be gaps.
As before, undefs are allowed and filled in with adjacent element loads.
Reviewers: HaoLiu, mssimpso
Subscribers: mkuper, delena, llvm-commits
Differential Revision: https://reviews.llvm.org/D23646
llvm-svn: 289573
Recommitting r288293 with some extra fixes for GlobalISel code.
Most of the exception handling members in MachineModuleInfo is actually
per function data (talks about the "current function") so it is better
to keep it at the function instead of the module.
This is a necessary step to have machine module passes work properly.
Also:
- Rename TidyLandingPads() to tidyLandingPads()
- Use doxygen member groups instead of "//===- EH ---"... so it is clear
where a group ends.
- I had to add an ugly const_cast at two places in the AsmPrinter
because the available MachineFunction pointers are const, but the code
wants to call tidyLandingPads() in between
(markFunctionEnd()/endFunction()).
Differential Revision: https://reviews.llvm.org/D27227
llvm-svn: 288405
Most of the exception handling members in MachineModuleInfo is actually
per function data (talks about the "current function") so it is better
to keep it at the function instead of the module.
This is a necessary step to have machine module passes work properly.
Also:
- Rename TidyLandingPads() to tidyLandingPads()
- Use doxygen member groups instead of "//===- EH ---"... so it is clear
where a group ends.
- I had to add an ugly const_cast at two places in the AsmPrinter
because the available MachineFunction pointers are const, but the code
wants to call tidyLandingPads() in between
(markFunctionEnd()/endFunction()).
Differential Revision: https://reviews.llvm.org/D27227
llvm-svn: 288293
Summary:
Variadic functions can be treated in the same way as normal functions
with respect to the number and types of parameters.
Reviewers: grosbach, olista01, t.p.northover, rengolin
Subscribers: javed.absar, aemerson, llvm-commits
Differential Revision: https://reviews.llvm.org/D26748
llvm-svn: 287219
One half of the shifts obviously needed conditional selection based on whether
the shift amount is more than 32-bits, but leaving the other half as the
natural shift isn't acceptable either: it's undefined behaviour to shift a
32-bit value by more than 31.
llvm-svn: 287149
This handles the last case of the builtin function calls that we would
generate code which differed from Microsoft's ABI. Rather than
generating a call to `__pow{d,s}i2` we now promote the parameter to a
float or double and invoke `powf` or `pow` instead.
Addresses PR30825!
llvm-svn: 286082
Summary: ARMv6m supports dmb etc fench instructions but not ldrex/strex etc. So for some atomic load/store, LLVM should inline instructions instead of lowering to __sync_ calls.
Reviewers: rengolin, efriedma, t.p.northover, jmolloy
Subscribers: efriedma, aemerson, llvm-commits
Differential Revision: https://reviews.llvm.org/D26120
llvm-svn: 285969
Generate the slowest possible codepath for noopt CodeGen. Even trying to be
clever with the negated jump can cause out-of-range jumps. Use a wide branch
instead. Although the code is modelled simplistically, the later optimizations
would recombine the branching into `cbz` if possible. This re-enables the
previous optimization as well as hopefully gives us working code in all cases.
Addresses PR30356!
llvm-svn: 285649
The Windows ARM target expects the compiler to emit a division-by-zero check.
The check would use the form of:
cmp r?, #0
cbz .Ltrap
b .Lbody
.Lbody:
...
.Ltrap:
udf #249 @ __brkdiv0
This works great most of the time. However, if the body of the function is
greater than 127 bytes, the branch target limitation of cbz becomes an issue.
This occurs in the unoptimized code generation cases sometimes (like in
compiler-rt).
Since this is a matter of correctness, possibly pay a small penalty instead. We
now form this slightly differently:
cbnz .Lbody
udf #249 @ __brkdiv0
.Lbody:
...
The positive case is through the branch instead of being the next instruction.
However, because of the basic block layout, the negated branch is going to be
a short distance always (2 bytes away, after the inserted __brkdiv0).
The new t__brkdiv0 instruction is required to explicitly mark the instruction as
a terminator as the generic UDF instruction is not a terminator.
Addresses PR30532!
llvm-svn: 285312
UMAAL is a DSP instruction and it is not available on thumbv7m
(Cortex-M3) and thumbv6m (Cortex-M0+1) targets. Also fix wrong
CHECK prefix in longMAC.ll test.
Patch by Vadzim Dambrouski.
Differential Revision: https://reviews.llvm.org/D25890
llvm-svn: 285278
The custom lowering is pretty straightforward: basically, just AND
together the two halves of a <4 x i32> compare.
Differential Revision: https://reviews.llvm.org/D25713
llvm-svn: 284536
This patch assigns cost of the scaling used in addressing.
On many ARM cores, a negated register offset takes longer than a
non-negated register offset, in a register-offset addressing mode.
For instance:
LDR R0, [R1, R2 LSL #2]
LDR R0, [R1, -R2 LSL #2]
Above, (1) takes less cycles than (2).
By assigning appropriate scaling factor cost, we enable the LLVM
to make the right trade-offs in the optimization and code-selection phase.
Differential Revision: http://reviews.llvm.org/D24857
Reviewers: jmolloy, rengolin
llvm-svn: 284127
Currently, the Int_eh_sjlj_dispatchsetup intrinsic is marked as
clobbering all registers, including floating-point registers that may
not be present on the target. This is technically true, as we could get
linked against code that does use the FP registers, but that will not
actually work, as the soft-float code cannot save and restore the FP
registers. SjLj exception handling can only work correctly if either all
or none of the code is built for a target with FP registers. Therefore,
we can assume that, when Int_eh_sjlj_dispatchsetup is compiled for a
soft-float target, it is only going to be linked against other
soft-float code, and so only clobbers the general-purpose registers.
This allows us to check that no non-savable registers are clobbered when
generating the prologue/epilogue.
Differential Revision: https://reviews.llvm.org/D25180
llvm-svn: 283866
Reapplying r283383 after revert in r283442. The additional fix
is a getting rid of a stray space in a function name, in the
refactoring part of the commit.
This avoids falling back to calling out to the GCC rem functions
(__moddi3, __umoddi3) when targeting Windows.
The __rt_div functions have flipped the two arguments compared
to the __aeabi_divmod functions. To match MSVC, we emit a
check for division by zero before actually calling the library
function (even if the library function itself also might do
the same check).
Not all calls to __rt_div functions for division are currently
merged with calls to the same function with the same parameters
for the remainder. This is more wasteful than a div + mls as before,
but avoids calls to __moddi3.
Differential Revision: https://reviews.llvm.org/D25332
llvm-svn: 283550
This reverts commit r283383 because it broke some of the bots:
undefined reference to ` __aeabi_uldivmod'
It affected (at least) clang-cmake-armv7-a15-selfhost,
clang-cmake-armv7-a15-selfhost and clang-native-arm-lnt.
llvm-svn: 283442
Global variables are GlobalValues, so they have explicit alignment. Querying
DataLayout for the alignment was incorrect.
Testcase added.
llvm-svn: 283423
This avoids falling back to calling out to the GCC rem functions
(__moddi3, __umoddi3) when targeting Windows.
The __rt_div functions have flipped the two arguments compared
to the __aeabi_divmod functions. To match MSVC, we emit a
check for division by zero before actually calling the library
function (even if the library function itself also might do
the same check).
Not all calls to __rt_div functions for division are currently
merged with calls to the same function with the same parameters
for the remainder. This is more wasteful than a div + mls as before,
but avoids calls to __moddi3.
Differential Revision: https://reviews.llvm.org/D24076
llvm-svn: 283383
library call to __aeabi_uidivmod. This is an improved implementation of
r280808, see also D24133, that got reverted because isel was stuck in a loop.
That was caused by the optimisation incorrectly triggering on i64 ints, which
shouldn't happen because there is no 64bit hwdiv support; that put isel's type
legalization and this optimisation in a loop. A native ARM compiler and testing
now shows that this is fixed.
Patch mostly by Pablo Barrio.
Differential Revision: https://reviews.llvm.org/D25077
llvm-svn: 283098
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
This recommit contains fixes for a nasty bug related to fast-isel fallback - because
fast-isel doesn't know about this optimization, if it runs and emits references to
a string that we inline (because fast-isel fell back to SDAG) we will end up
with an inlined string and also an out-of-line string, and we won't emit the
out-of-line string, causing backend failures.
It also contains fixes for emitting .text relocations which made the sanitizer
bots unhappy.
llvm-svn: 282387
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
This recommit contains fixes for a nasty bug related to fast-isel fallback - because
fast-isel doesn't know about this optimization, if it runs and emits references to
a string that we inline (because fast-isel fell back to SDAG) we will end up
with an inlined string and also an out-of-line string, and we won't emit the
out-of-line string, causing backend failures.
It also contains fixes for emitting .text relocations which made the sanitizer
bots unhappy.
llvm-svn: 282241
(and the same for SREM)
This was causing buildbot failures earlier (time outs in the LNT suite).
However, we haven't been able to reproduce this and are suspecting this
was caused by another (reverted) patch.
llvm-svn: 281719
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
This recommit contains fixes for a nasty bug related to fast-isel fallback - because
fast-isel doesn't know about this optimization, if it runs and emits references to
a string that we inline (because fast-isel fell back to SDAG) we will end up
with an inlined string and also an out-of-line string, and we won't emit the
out-of-line string, causing backend failures.
It also contains fixes for emitting .text relocations which made the sanitizer
bots unhappy.
llvm-svn: 281715
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
This recommit contains fixes for a nasty bug related to fast-isel fallback - because
fast-isel doesn't know about this optimization, if it runs and emits references to
a string that we inline (because fast-isel fell back to SDAG) we will end up
with an inlined string and also an out-of-line string, and we won't emit the
out-of-line string, causing backend failures.
llvm-svn: 281604
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
llvm-svn: 281484
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
llvm-svn: 281314
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
llvm-svn: 281213
Summary:
An IR load can be invariant, dereferenceable, neither, or both. But
currently, MI's notion of invariance is IR-invariant &&
IR-dereferenceable.
This patch splits up the notions of invariance and dereferenceability at
the MI level. It's NFC, so adds some probably-unnecessary
"is-dereferenceable" checks, which we can remove later if desired.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D23371
llvm-svn: 281151
Move the target specific setup into the target specific lowering setup. As
pointed out by Anton, the initial change was moving this too high up the stack
resulting in a violation of the layering (the target generic code path setup
target specific bits). Sink this into the ARM specific setup. NFC.
llvm-svn: 281088
This reverts commit r280808.
It is possible that this change results in an infinite loop. This
is causing timeouts in some tests on ARM, and a Chromebook bot is
failing.
llvm-svn: 280918
Summary:
This saves a library call to __aeabi_uidivmod. However, the
processor must feature hardware division in order to benefit from
the transformation.
Reviewers: scott-0, jmolloy, compnerd, rengolin
Subscribers: t.p.northover, compnerd, aemerson, rengolin, samparker, llvm-commits
Differential Revision: https://reviews.llvm.org/D24133
llvm-svn: 280808
This is a mechanical change of comments in switches like fallthrough,
fall-through, or fall-thru to use the LLVM_FALLTHROUGH macro instead.
llvm-svn: 278902
This patch adds support for some new relocation models to the ARM
backend:
* Read-only position independence (ROPI): Code and read-only data is accessed
PC-relative. The offsets between all code and RO data sections are known at
static link time. This does not affect read-write data.
* Read-write position independence (RWPI): Read-write data is accessed relative
to the static base register (r9). The offsets between all writeable data
sections are known at static link time. This does not affect read-only data.
These two modes are independent (they specify how different objects
should be addressed), so they can be used individually or together. They
are otherwise the same as the "static" relocation model, and are not
compatible with SysV-style PIC using a global offset table.
These modes are normally used by bare-metal systems or systems with
small real-time operating systems. They are designed to avoid the need
for a dynamic linker, the only initialisation required is setting r9 to
an appropriate value for RWPI code.
I have only added support to SelectionDAG, not FastISel, because
FastISel is currently disabled for bare-metal targets where these modes
would be used.
Differential Revision: https://reviews.llvm.org/D23195
llvm-svn: 278015
Summary:
Commit 276701 requires that targets have the DSP extensions to use
certain saturating instructions. This requires some corrections.
For ARM ISA the instructions in question are available in all v6*
architectures.
For Thumb2, the instructions in question are available from v6T2.
SSAT and USAT are part of the base architecture while SSAT16 and
USAT16 require the DSP extensions.
Reviewers: rengolin
Subscribers: aemerson, rengolin, samparker, llvm-commits
Differential Revision: https://reviews.llvm.org/D23010
llvm-svn: 277439
Summary:
The MOV/MOVT instructions being chosen for struct_byval predicates was
conditional only on Thumb2, resulting in an ARM MOV/MOVT instruction
being incorrectly emitted in Thumb1 mode. This is especially apparent
with v8-m.base targets. This patch ensures that Thumb instructions are
emitted in both Thumb modes.
Reviewers: rengolin, t.p.northover
Subscribers: llvm-commits, aemerson, rengolin
Differential Revision: https://reviews.llvm.org/D22865
llvm-svn: 277128
The saturation instructions appeared in v6T2, with DSP extensions, but they
were being accepted / generated on any, with the new introduction of the
saturation detection in the back-end. This commit restricts the usage to
DSP-enable only cores.
Fixes PR28607.
llvm-svn: 276701
Inference of the 'returned' attribute was fixed in r276008, lets try
turning the backend support back on.
This reverts commit r275677.
llvm-svn: 276081
At higher optimization levels, we generate the libcall for DIVREM_Ix, which is
fine: aeabi_{u|i}divmod. At -O0 we generate the one for REM_Ix, which is the
default {u}mod{q|h|s|d}i3.
This commit makes sure that we don't generate REM_Ix calls for ABIs that
don't support them (i.e. where we need to use DIVREM_Ix instead). This is
achieved by bailing out of FastISel, which can't handle non-double multi-reg
returns, and letting the legalization infrastructure expand the REM_Ix calls.
It also updates the divmod-eabi.ll test to run under -O0 as well, and adds some
Windows checks to it to make sure we don't break things for it.
Fixes PR27068
Differential Revision: https://reviews.llvm.org/D21926
llvm-svn: 275773
r275042 reverted function-attribute inference for the 'returned' attribute
because the feature triggered self-hosting failures on ARM and AArch64. James
Molloy determined that the this-return argument forwarding feature, which
directly ties the returned input argument to the returned value, was the cause.
It seems likely that this forwarding code contains, or triggers, a subtle bug.
Disabling for now until we can track that down.
llvm-svn: 275677
Summary:
Instead, we take a single flags arg (a bitset).
Also add a default 0 alignment, and change the order of arguments so the
alignment comes before the flags.
This greatly simplifies many callsites, and fixes a bug in
AMDGPUISelLowering, wherein the order of the args to getLoad was
inverted. It also greatly simplifies the process of adding another flag
to getLoad.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, jyknight, dsanders, nemanjai, llvm-commits
Differential Revision: http://reviews.llvm.org/D22249
llvm-svn: 275592
Thumb-1 doesn't have post-inc or pre-inc load or store instructions. However the LDM/STM instructions with writeback can function as post-inc load/store:
ldm r0!, {r1} @ load from r0 into r1 and increment r0 by 4
Obviously, this only works if the post increment is 4.
llvm-svn: 275540
... When we emit several calls to the same function in the same basic block.
An indirect call uses a "BLX r0" instruction which has a 16-bit encoding. If many calls are made to the same target, this can enable significant code size reductions.
llvm-svn: 275537
Remove remaining implicit conversions from MachineInstrBundleIterator to
MachineInstr* from the ARM backend. In most cases, I made them less attractive
by preferring MachineInstr& or using a ranged-based for loop.
Once all the backends are fixed I'll make the operator explicit so that this
doesn't bitrot back.
llvm-svn: 274920
Not all code-paths set the relocation model to static for Windows. This
currently breaks on Windows ARM with `-mlong-calls` when built with clang.
Loosen the assertion to what it was previously. We would ideally ensure that
all the configuration sets Windows to static relocation model.
llvm-svn: 274570
For the most part this simplifies all callers. There were two places in X86 that needed an explicit makeArrayRef to shorten a statically sized array.
llvm-svn: 274337
This is a mechanical change to make TargetLowering API take MachineInstr&
(instead of MachineInstr*), since the argument is expected to be a valid
MachineInstr. In one case, changed a parameter from MachineInstr* to
MachineBasicBlock::iterator, since it was used as an insertion point.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
llvm-svn: 274287
This is mostly a mechanical change to make TargetInstrInfo API take
MachineInstr& (instead of MachineInstr* or MachineBasicBlock::iterator)
when the argument is expected to be a valid MachineInstr. This is a
general API improvement.
Although it would be possible to do this one function at a time, that
would demand a quadratic amount of churn since many of these functions
call each other. Instead I've done everything as a block and just
updated what was necessary.
This is mostly mechanical fixes: adding and removing `*` and `&`
operators. The only non-mechanical change is to split
ARMBaseInstrInfo::getOperandLatencyImpl out from
ARMBaseInstrInfo::getOperandLatency. Previously, the latter took a
`MachineInstr*` which it updated to the instruction bundle leader; now,
the latter calls the former either with the same `MachineInstr&` or the
bundle leader.
As a side effect, this removes a bunch of MachineInstr* to
MachineBasicBlock::iterator implicit conversions, a necessary step
toward fixing PR26753.
Note: I updated WebAssembly, Lanai, and AVR (despite being
off-by-default) since it turned out to be easy. I couldn't run tests
for AVR since llc doesn't link with it turned on.
llvm-svn: 274189
Summary:
SSAT saturates an integer, making sure that its value lies within
an interval [-k, k]. Since the constant is given to SSAT as the
number of bytes set to one, k + 1 must be a power of 2, otherwise
the optimization is not possible. Also, the select_cc must use <
and > respectively so that they define an interval.
Reviewers: mcrosier, jmolloy, rengolin
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D21372
llvm-svn: 273581
This is a cleanup commit similar to r271555, but for ARM.
The end goal is to get rid of the isSwift / isCortexXY / isWhatever methods.
Since the ARM backend seems to have quite a lot of calls to these methods, I
intend to submit 5-6 subtarget features at a time, instead of one big lump.
Differential Revision: http://reviews.llvm.org/D21432
llvm-svn: 273544
The setCallee function will set the number of fixed arguments based
on the size of the argument list. The FixedArgs parameter was often
explicitly set to 0, leading to a lack of consistent value for non-
vararg functions.
Differential Revision: http://reviews.llvm.org/D20376
llvm-svn: 273403
TargetLowering and DAGToDAG are used to combine ADDC, ADDE and UMLAL
dags into UMAAL. Selection is split into the two phases because it
is easier to match the two patterns at those different times.
Differential Revision: http://http://reviews.llvm.org/D21461
llvm-svn: 273165
Reduces a bit of code duplication and clarify where we are interested
just on position independence and no the location of the symbol.
llvm-svn: 273164
The R_ARM_PLT32 relocation is deprecated and is not produced by MC.
This means that the code being deleted is dead from the .o point of
view and was making the .s more confusing.
llvm-svn: 272909
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.
llvm-svn: 272512
As suggested by clang-tidy's performance-unnecessary-copy-initialization.
This can easily hit lifetime issues, so I audited every change and ran the
tests under asan, which came back clean.
llvm-svn: 272126
TLS access requires an offset from the TLS index. The index itself is the
section-relative distance of the symbol. For ARM, the relevant relocation
(IMAGE_REL_ARM_SECREL) is applied as a constant. This means that the value may
not be an immediate and must be lowered into a constant pool. This offset will
not be base relocated. We were previously emitting the actual address of the
symbol which would be base relocated and would therefore be the vaue offset by
the ImageBase + TLS Offset.
llvm-svn: 271974
new instruction to ARM and AArch64 targets and several system registers.
Patch by: Roger Ferrer Ibanez and Oliver Stannard
Differential Revision: http://reviews.llvm.org/D20282
llvm-svn: 271670
I'm really not sure why we were in the first place, it's the linker's job to
convert between BL/BLX as necessary. Even worse, using BLX left Thumb calls
that could be locally resolved completely unencodable since all offsets to BLX
are multiples of 4.
rdar://26182344
llvm-svn: 269101
Summary:
This patch adds support for the X asm constraint.
To do this, we lower the constraint to either a "w" or "r" constraint
depending on the operand type (both constraints are supported on ARM).
Fixes PR26493
Reviewers: t.p.northover, echristo, rengolin
Subscribers: joker.eph, jgreenhalgh, aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D19061
llvm-svn: 267411
This corrects the MI annotations for the stack adjustment following the __chkstk
invocation. We were marking the original SP usage as a Def rather than Kill.
The (new) assigned value is the definition, the original reference is killed.
Adjust the ISelLowering to mark Kills and FrameSetup as well.
This partially resolves PR27480.
llvm-svn: 267361
Because lowering of CMP_SWAP_64 occurs during type legalization, there can be
i64 types produced by more than just a BUILD_PAIR or similar. My initial tests
used just incoming function args.
llvm-svn: 266828
Both AArch64 and ARM support llvm.<arch>.thread.pointer intrinsics that
just return the thread pointer. I have a pending patch that does the same
for SystemZ (D19054), and there are many more targets that could benefit
from one.
This patch merges the ARM and AArch64 intrinsics into a single target
independent one that will also be used by subsequent targets.
Differential Revision: http://reviews.llvm.org/D19098
llvm-svn: 266818
The fast register-allocator cannot cope with inter-block dependencies without
spilling. This is fine for ldrex/strex loops coming from atomicrmw instructions
where any value produced within a block is dead by the end, but not for
cmpxchg. So we lower a cmpxchg at -O0 via a pseudo-inst that gets expanded
after regalloc.
Fortunately this is at -O0 so we don't have to care about performance. This
simplifies the various axes of expansion considerably: we assume a strong
seq_cst operation and ensure ordering via the always-present DMB instructions
rather than v8 acquire/release instructions.
Should fix the 32-bit part of PR25526.
llvm-svn: 266679
It is very likely that the swiftself parameter is alive throughout most
functions function so putting it into a callee save register should
avoid spills for the callers with only a minimum amount of extra spills
in the callees.
Currently the generated code is correct but unnecessarily spills and
reloads arguments passed in callee save registers, I will address this
in upcoming patches.
This also adds a missing check that for tail calls the preserved value
of the caller must be the same as the callees parameter.
Differential Revision: http://reviews.llvm.org/D18901
llvm-svn: 266253
Summary:
In the context of http://wg21.link/lwg2445 C++ uses the concept of
'stronger' ordering but doesn't define it properly. This should be fixed
in C++17 barring a small question that's still open.
The code currently plays fast and loose with the AtomicOrdering
enum. Using an enum class is one step towards tightening things. I later
also want to tighten related enums, such as clang's
AtomicOrderingKind (which should be shared with LLVM as a 'C++ ABI'
enum).
This change touches a few lines of code which can be improved later, I'd
like to keep it as NFC for now as it's already quite complex. I have
related changes for clang.
As a follow-up I'll add:
bool operator<(AtomicOrdering, AtomicOrdering) = delete;
bool operator>(AtomicOrdering, AtomicOrdering) = delete;
bool operator<=(AtomicOrdering, AtomicOrdering) = delete;
bool operator>=(AtomicOrdering, AtomicOrdering) = delete;
This is separate so that clang and LLVM changes don't need to be in sync.
Reviewers: jyknight, reames
Subscribers: jyknight, llvm-commits
Differential Revision: http://reviews.llvm.org/D18775
llvm-svn: 265602
We can only perform a tail call to a callee that preserves all the
registers that the caller needs to preserve.
This situation happens with calling conventions like preserver_mostcc or
cxx_fast_tls. It was explicitely handled for fast_tls and failing for
preserve_most. This patch generalizes the check to any calling
convention.
Related to rdar://24207743
Differential Revision: http://reviews.llvm.org/D18680
llvm-svn: 265329
ThreadModel::Single is already handled already by ARMPassConfig adding
LowerAtomicPass to the pass list, which lowers all atomics to non-atomic
ops and deletes fences.
So by the time we get to ISel, there's no atomic fences left, so they
don't need special handling.
llvm-svn: 265178
It is possible to have a fallthrough MBB prior to MBB placement. The original
addition of the BB would result in reordering the BB as not preceding the
successor. Because of the fallthrough nature of the BB, we could end up
executing incorrect code or even a constant pool island! Insert the spliced BB
into the same location to avoid that.
Thanks to Tim Northover for invaluable hints and Fiora for the discussion on
what may have been occurring!
llvm-svn: 264454
We did not have an explicit branch to the continuation BB. When the check was
hoisted, this could permit control follow to fall through into the division
trap. Add the explicit branch to the continuation basic block to ensure that
code execution is correct.
llvm-svn: 264370
This introduces a custom lowering for ISD::SETCCE (introduced in r253572)
that allows us to emit a short code sequence for 64-bit compares.
Before:
push {r7, lr}
cmp r0, r2
mov.w r0, #0
mov.w r12, #0
it hs
movhs r0, #1
cmp r1, r3
it ge
movge.w r12, #1
it eq
moveq r12, r0
cmp.w r12, #0
bne .LBB1_2
@ BB#1: @ %bb1
bl f
pop {r7, pc}
.LBB1_2: @ %bb2
bl g
pop {r7, pc}
After:
push {r7, lr}
subs r0, r0, r2
sbcs.w r0, r1, r3
bge .LBB1_2
@ BB#1: @ %bb1
bl f
pop {r7, pc}
.LBB1_2: @ %bb2
bl g
pop {r7, pc}
Saves around 80KB in Chromium's libchrome.so.
Some notes on this patch:
- I don't much like the ARMISD::BRCOND and ARMISD::CMOV combines I
introduced (nothing else needs them). However, they are necessary in
order to avoid poor codegen, and they seem similar to existing combines
in other backends (e.g. X86 combines (brcond (cmp (setcc Compare))) to
(brcond Compare)).
- No support for Thumb-1. This is in principle possible, but we'd need
to implement ARMISD::SUBE for Thumb-1.
Differential Revision: http://reviews.llvm.org/D15256
llvm-svn: 263962
The two changes together weakened the test and caused a regression with division
handling in MSVC mode. They were applied to avoid an assertion being triggered
in the block frequency analysis. However, the underlying problem was simply
being masked rather than solved properly. Address the actual underlying problem
and revert the changes. Rather than analyze the cause of the assertion, the
division failure was assumed to be an overflow.
The underlying issue was a subtle bug in the BB construction in the emission of
the div-by-zero check (WIN__DBZCHK). We did not construct the proper successor
information in the basic blocks, nor did we update the PHIs associated with the
basic block when we split them. This would result in assertions being triggered
in the block frequency analysis pass.
Although the original tests are being removed, the tests themselves performed
very little in terms of validation but merely tested that we did not assert when
generating code. Update this with new tests that actually ensure that we do not
regress on the code generation.
llvm-svn: 263714
David Green