ComputePHILiveOutRegInfo assumes that constant incoming values to
Phis will be zero extended if they aren't a legal type. To guarantee
that we should zero_extend rather than any_extend constants.
This fixes a bug for RISCV where any_extend of constants can be
treated as a sign_extend.
Differential Revision: https://reviews.llvm.org/D122053
The code that inserts AssertZExt based on predecessor information assumes
constants are zero extended for phi incoming values this allows
AssertZExt to be created in blocks consuming a Phi.
SelectionDAG::getNode treats any_extend of i32 constants as sext for RISCV.
The code that creates phi incoming values in the predecessors creates an
any_extend for the constants which then gets treated as a sext by getNode.
This makes the AssertZExt incorrect and can cause zexts to be
incorrectly removed.
This bug was introduced by D105918
Differential Revision: https://reviews.llvm.org/D122052
This patch adds single-bit and bit-counting ops to list of sign-extending ops.
A single-bit write propagates sign-extendedness if it's not in the sign-bits.
Bit extraction and bit counting always outputs a small number, so sign-extended.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D121152
Currently we allow half types in vectors if the scalar Zfh extension
is enabled. This behavior is not inline with the vector spec. For f32
and f64 types, the Zve32f, Zve64f, Zve64d, and V explicitly control
the availablity of floating point types in vectors.
In order to make our compiler compliant, we either need to remove all support
for half in vectors or we need an extension to control it.
Draft spec here https://github.com/riscv/riscv-v-spec/pull/780
Reviewed By: kito-cheng
Differential Revision: https://reviews.llvm.org/D121345
We have a special case to skip this transform if c1 is 0xffffffff
and x is sext_inreg in order to use sraiw+zext.w. But we were only
checking that we have a sext_inreg opcode, not how many bits are
being sign extended.
This commit adds a check that it is a sext_inreg from i32 so we know for
sure that an sraiw can be created.
Since we mark the pseudos as mayLoad but do not provide any MMOs,
isSafeToMove conservatively returns false, stopping MachineLICM from
hoisting the instructions. PseudoLA_TLS_GD does not actually expand to a
load, so stop marking that as mayLoad to allow it to be hoisted, and for
the others make sure to add MMOs during lowering to indicate they're GOT
loads and thus can be freely moved.
Fixes https://github.com/llvm/llvm-project/issues/54372
Reviewed By: MaskRay, arichardson
Differential Revision: https://reviews.llvm.org/D121654
Select SRLI+SLLI for and i64 %x, imm if the imm is a leading ones mask.
It's useful in RV64 when the mask exceeds simm32 (cannot be generated by LUI).
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D121598
If we promote the ABS and then Expand in LegalizeDAG, then both the
sra and the xor will have their inputs sign extended. This generates
extra code on RISCV which lacks an i8 or i16 sign extend instructon.
If we expand during type legalization, then only the sra will get its
input sign extended. RISCV is able to combine this with the sra by
doing a shift left followed by an sra.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D121664
RISCV strong prefers i32 values be sign extended to i64. This combine
was always zero extending the constant using APInt methods.
This adjusts the code so that it calls getNode using ISD::ANY_EXTEND instead.
getNode will call TLI.isSExtCheaperThanZExt to decide how to handle
the constant.
Tests were copied from D121598 where I noticed that we were creating
constants that were hard to materialize.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D121650
The InstAlias framework cannot match registers against zero_reg, which
RVV uses to encode unmasked operations.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D92228
If the type is less than XLenVT, type legalization will turn this
into (srl (bitreverse (bswap (srl (bswap X), C))), C). We can't
completely recover from these shifts. They introduce zeros into
the upper bits of the result and we can't easily tell if they are
needed. By doing a DAG combine early, we avoid introducing these
shifts.
Type legalize narrow RISCVISD::GREV/GORC with constant to a larger
type without switching to W. Detect sext_inreg+gorci/grevi with a
uimm5 immediate during isel to emit GREVIW/GORCIW.
This allows us to better propagate known bits information through
extended bits after type legalization. It will also simplify a
change I'm considering for BREV8 with Zbkb.
A future patch will add computeKnownBits support for GORC.
A further improvement here would be to use hasAllWUsers and
doPeepholeSExtW like we do for SLLIW, but I don't think we have
the test coverage for that yet.
We currently type legalize to the W form, but type legalization
doesn't place any requirements on the extended bits. So we are ok
to use GREVI/GORCI for type legalization as long as the control
doesn't cross any bits from the extended bits into the lower bits.
This can allow us to recognize cases where the extended bits end
up being all zeros and we can propagate that information through.
My plan is to move greviw/gorciw formation to isel patterns similar
to slliw.
We already do this for RISCVISD::VFMV_S_F_VL and the vfmv.v.f
intrinsic.
Reviewed By: kito-cheng
Differential Revision: https://reviews.llvm.org/D121429
This helps us form vfnmsub, vfnmadd, and vfmusb from masked VP
intrinsics.
I've used "srcvalue" for the mask parameter in the fneg nodes. We
can't match "V0" because that doesn't ensure the mask the is the same.
Instead it matches two different nodes and generates two copies to
V0 of those separate values.
Reviewed By: rogfer01
Differential Revision: https://reviews.llvm.org/D120287
The crypto extension have several shorthand extensions that don't consist of any extra instructions.
Take `zk` for example, while the extension would imply `zkn, zkr, zkt`. The 3 extensions should also
combine back into `zk` to maintain the canonical order in isa strings.
This patch addresses the above.
Reviewed By: VincentWu
Differential Revision: https://reviews.llvm.org/D119530
vmsgeu.vi with 0 is always true, but in the masked with mask undisturbed
policy, we still need to keep inactive elelemt which come from maskedoff.
We could return mask directly if it's mask agnostic policy in the future.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D121080
We should not emit a tail agnostic vlse for a tail undisturbed vmv.s.x
In D119688:
- if (IsScalarMove && !Node->getOperand(0).isUndef())
+ bool HasPassthruOperand = Node->getOpcode() != ISD::SPLAT_VECTOR;
+ if (HasPassthruOperand && !IsScalarMove &&
!Node->getOperand(0).isUndef())
break;
The IsScalarMove check in the if statement had been changed.
Differential Revision: https://reviews.llvm.org/D120963
setgt X, -1 is the canonical form of setge X, 0. We can swap the
select operands and use setlt X, X0 when selecting CMOV. This
avoid materializing the -1 in a register.
With Zbb, abs is expanded to (max X, neg) by default. If X has 33 or
more sign bits, we can expand it a little early using negw instead of
neg to save a sext_inreg. If X started as a 32 bit value, type
legalization would have inserted a sext before the abs so X having
33 sign bits should always be true.
Note: I've used ISD::FREEZE here since we increase the number of uses.
Our default expansion for ABS doesn't do that, but I think that's a bug.
We can't do this with custom type legalization because ISD::FREEZE
doesn't propagate sign bits so later DAG combine won't expand be
able to see optmize it.
Alives2 https://alive2.llvm.org/ce/z/Gx3RNe
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D120597
Until Zfinx is supported in CodeGen we need to convert all Zfinx
register classes to GPR.
Remove the zfinx-types.ll test which didn't test anything meaningful
since -mattr=zfinx isn't implemented completely in llc.
Follow up to D93298.
Instead of emitting 0 > Hi, emit Hi < 0. If Hi needs to be expanded again
this will allow the special case for sign bit tests in ExpandIntOp_SETCC
to trigger.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D120761
This miscompile was introduced in D119527.
This was a special pattern for rotate+bswap on RV32. It doesn't
work for RV64 since the rotate needs to be half the bitwidth. The
equivalent pattern for RV64 is ROTR ((GREV x, 56), 32) so match
that instead.
This could be generalized further as noted in the new FIXME.
Reviewed By: Chenbing.Zheng
Differential Revision: https://reviews.llvm.org/D120686
This patch added the MC layer support of Zfinx extension.
Authored-by: StephenFan
Co-Authored-by: Shao-Ce Sun
Reviewed By: asb
Differential Revision: https://reviews.llvm.org/D93298
This adds tests for i8 through i128 with intrinsic and select forms.
Covering rv32 and rv64 with the base ISA, Zbb, and Zbt. Some
Zbb tests already covered part of this, but not all.
FIXMEs have been added for some obviously suboptimal codegen.
Many of these test cases had a single space before 'ret' while
every other instruction had two space indentation. I did not audit
any other tests for this problem.
This lowers VECTOR_SPLICE of scalable vectors to a slidedown follow by a slideup.
Fixed vectors are encouraged to use shufflevector instruction. The equivalent patch
for fixed vectors is D119039.
I've used a tail agnostic slidedown and limited the VL to only the
elements that will not be overwritten by the slideup. The slideup
uses VLMax for its VL. It unfortunately uses tail undisturbed policy
but it isn't required as there is no tail. We just need the merge
operand to carry the bits for the lower portion of the result.
Care was taken to ensure that either the slideup or slidedown will
be able to use a .vi instruction when the immediate is small. Which
one uses the immediate depends on the sign of the immediate.
Reviewed By: frasercrmck, ABataev
Differential Revision: https://reviews.llvm.org/D119303
If the types aren't legal, the expansions may get type legalized in a
different way preventing code sharing. If the type is legal, we will
share some instructions between the two expansions, but we will need an
extra register.
Since we don't appear to fold (neg (sub A, B)) if the sub has an
additional user, I think it makes sense not to expand NABS.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D120513
Default type legalization will create sext_inreg+abs, but we may
not be able to remove the sext_inreg.
Instead this patch expands abs during type legalization to
Y = sraiw X, 31; subw(xor X, Y), Y) which doesn't require the input
to be sign extended.
This gives a big improvement for some neg-abs tests where the
abs is used more than the the neg. Previously the abs was expanded
a different way before and after type legalization. Now they are
expanded in a similar way enabling more CSE.
Reviewed By: asb
Differential Revision: https://reviews.llvm.org/D120636
In this patch, we add a more narrower exclusion for
zeroext (srl x) -> srli (slli x), so that it provides an opportunity
for the selection of sraiw.
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D120467
This was a test for an infinite loop so the CHECK lines don't really
matter, but they'd get generated the next time someone runs the script
on the file so might as well do it while I'm touching it.
Craig Topper