These patterns were omitted because clang only allows converting between
these types using intrinsics, but other front-ends or optimisation
passes may want to use them.
Differential revision: https://reviews.llvm.org/D119354
There's a few relevant forward declarations in there that may require downstream
adding explicit includes:
llvm/MC/MCContext.h no longer includes llvm/BinaryFormat/ELF.h, llvm/MC/MCSubtargetInfo.h, llvm/MC/MCTargetOptions.h
llvm/MC/MCObjectStreamer.h no longer include llvm/MC/MCAssembler.h
llvm/MC/MCAssembler.h no longer includes llvm/MC/MCFixup.h, llvm/MC/MCFragment.h
Counting preprocessed lines required to rebuild llvm-project on my setup:
before: 1052436830
after: 1049293745
Which is significant and backs up the change in addition to the usual benefits of
decreasing coupling between headers and compilation units.
Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D119244
AArch32/Armv8A introduced the performance deprecation of certain patterns
of IT instructions. After some debate internal to ARM, this is now being
reverted; i.e. no IT instruction patterns are performance deprecated
anymore, as the perfomance degredation is not significant enough.
This reverts the following:
"ARMv8-A deprecates some uses of the T32 IT instruction. All uses of
IT that apply to instructions other than a single subsequent 16-bit
instruction from a restricted set are deprecated, as are explicit
references to the PC within that single 16-bit instruction. This permits
the non-deprecated forms of IT and subsequent instructions to be treated
as a single 32-bit conditional instruction."
The deprecation no longer applies, but the behaviour may be controlled
by the -arm-restrict-it and -arm-no-restrict-it command-line options,
with the latter being the default. No warnings about complex IT blocks
will be generated.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D118044
This way they get lowered through the ARMISD::BUILD_VECTOR, which can
produce more efficient D register moves.
Also helps D115653 not get stuck in a loop.
None of the external users actual touch these (they're purely used internally down the recursive call) - its trivial to add another wrapper if anything ever does want to track known elements.
Currently, ARMBaseInstrInfo::getInstSizeInBytes() uses hard-coded
instruction size for some pseudo-instructions, while this
information should ideally be found in ARMInstrInfo.td,
ARMInstrThumb(2).td files (which can be accessed via MCInstrDesc). Hence,
the .td files should be updated and no hard-coded instruction sizes
should be used by getInstSizeInBytes() anymore.
Differential Revision: https://reviews.llvm.org/D118009
I have updated TargetLowering::isConstTrueVal to also consider
SPLAT_VECTOR nodes with constant integer operands. This allows the
optimisation to also work for targets that support scalable vectors.
Differential Revision: https://reviews.llvm.org/D117210
Inspecting the pointer element type here is incompatible with
opaque pointers, and doesn't seem necessary to me. I think the
intention might have been to check the type of load/store pointer
arguments, but I believe those should get checked through their
return type or value operand anyway. I don't get any test failures
if I simply drop this.
Differential Revision: https://reviews.llvm.org/D118353
Since it's introduction, the qrdmlah has been represented as a qrdmulh
and a sadd_sat. This doesn't produce the same result for all input
values though. This patch fixes that by introducing a qrdmlah (and
qrdmlsh) intrinsic specifically for the vqrdmlah and sqrdmlah
instructions. The old test cases will now produce a qrdmulh and sqadd,
as expected.
Fixes#53120 and #50905 and #51761.
Differential Revision: https://reviews.llvm.org/D117592
This reverts commit ef82063207.
- It conflicts with the existing llvm::size in STLExtras, which will now
never be called.
- Calling it without llvm:: breaks C++17 compat
Instead use either Type::getPointerElementType() or
Type::getNonOpaquePointerElementType().
This is part of D117885, in preparation for deprecating the API.
The cleanup was manual, but assisted by "include-what-you-use". It consists in
1. Removing unused forward declaration. No impact expected.
2. Removing unused headers in .cpp files. No impact expected.
3. Removing unused headers in .h files. This removes implicit dependencies and
is generally considered a good thing, but this may break downstream builds.
I've updated llvm, clang, lld, lldb and mlir deps, and included a list of the
modification in the second part of the commit.
4. Replacing header inclusion by forward declaration. This has the same impact
as 3.
Notable changes:
- llvm/Support/TargetParser.h no longer includes llvm/Support/AArch64TargetParser.h nor llvm/Support/ARMTargetParser.h
- llvm/Support/TypeSize.h no longer includes llvm/Support/WithColor.h
- llvm/Support/YAMLTraits.h no longer includes llvm/Support/Regex.h
- llvm/ADT/SmallVector.h no longer includes llvm/Support/MemAlloc.h nor llvm/Support/ErrorHandling.h
You may need to add some of these headers in your compilation units, if needs be.
As an hint to the impact of the cleanup, running
clang++ -E -Iinclude -I../llvm/include ../llvm/lib/Support/*.cpp -std=c++14 -fno-rtti -fno-exceptions | wc -l
before: 8000919 lines
after: 7917500 lines
Reduced dependencies also helps incremental rebuilds and is more ccache
friendly, something not shown by the above metric :-)
Discourse thread on the topic: https://llvm.discourse.group/t/include-what-you-use-include-cleanup/5831
If you want to check for all uses of PAC, the SpillsLR argument to
shouldSignReturnAddress should be true instead of false, as that value will be
returned from the function if the other checks fall through.
Reviewed By: miyuki
Differential Revision: https://reviews.llvm.org/D116213
This is required to query the legality more precisely in the LoopVectorizer.
This adds another TTI function named 'forceScalarizeMaskedGather/Scatter'
function to work around the hack introduced for MVE, where
isLegalMaskedGather/Scatter would return an answer by second-guessing
where the function was called from, based on the Type passed in (vector
vs scalar). The new interface makes this explicit. It is also used by
X86 to check for vector widths where gather/scatters aren't profitable
(or don't exist) for certain subtargets.
Differential Revision: https://reviews.llvm.org/D115329
FeaturePerfMon relates to the PMU extensions available in armv7-a, and
should not be available in v7-m (it requires loading from a system
register with a mrc). Sink it down a level in the dependency map so that
it isn't present in ARMv7m or HasV8MMainlineOps.
It is also removed from the Neoverse-N2, as it will already be
transitively included.
Differential Revision: https://reviews.llvm.org/D117022
The interface for these instructions changed with support for mandatory tail
calls, and now -1 indicates the CalleePopAmount argument is not valid.
Unfortunately I didn't realise FastISel or GISel did calls at the time so
didn't update them.
This reverts commit fd4808887e.
This patch causes gcc to issue a lot of warnings like:
warning: base class ‘class llvm::MCParsedAsmOperand’ should be
explicitly initialized in the copy constructor [-Wextra]
This patch introduces support for targetting the Armv9.3-A architecture,
which should map to the existing Armv8.8-A extensions.
Differential Revision: https://reviews.llvm.org/D116158
This adds at extra check into ARMBaseInstrInfo::verifyInstruction to
verify the offsets used in addressing mode immediates using
isLegalAddressImm. Some tests needed fixing up as a result, adjusting
the opcode created from CMSE stack adjustments.
Differential Revision: https://reviews.llvm.org/D114939
This is the first commit in a series that implements support for
"armv8.8-a" architecture. This should contain all the necessary
boilerplate to make the 8.8-A architecture exist from LLVM and Clang's
point of view: it adds the new arch as a subtarget feature, a definition
in TargetParser, a name on the command line, an appropriate set of
predefined macros, and adds appropriate tests. The new architecture name
is supported in both AArch32 and AArch64.
However, in this commit, no actual _functionality_ is added as part of
the new architecture. If you specify -march=armv8.8a, the compiler
will accept it and set the right predefines, but generate no code any
differently.
Differential Revision: https://reviews.llvm.org/D115694
A 'CMOV 1, 0, CC, %cpsr, Cmp' is the same as a 'CSINC 0, 0, CC, Cmp',
and can be treated the same in IsCMPZCSINC added in D114013. This allows
us to remove the unnecessary CMOV in the same way that we could remove a
CSINC.
Differential Revision: https://reviews.llvm.org/D115188
This makes use of the code in D114013 to fold away unnecessary
CMPZ/CSINC starting from a CMOV, in a similar way to how we fold away
CSINV/CSINC/etc
Differential Revision: https://reviews.llvm.org/D115185
Some MVE instructions have qr variants that take a Q and R register,
splatting the R register for each lane. This is usually handled fine for
standard splats as we sink the splat into the loop and combine the
resulting dup into the qr instruction. It does not work for constant
splats though, as we generate a vmovimm or constant pool load instead.
This intercepts that, generating a vdup of the constant instead where we
can turn the result into a qr instruction variant.
Differential Revision: https://reviews.llvm.org/D115242
As reported from a failing firefox build, we can sometimes get frame
indices with negative offsets from a t2LDRi8. This adds support for
them, to prevent the crash.
We can be in situations where And 1 zext nodes will not have been yet,
preventing us from detecting removable cmpz/csinc patterns. This peeks
through those nodes allowing us to simplify more code.
Differential Revision: https://reviews.llvm.org/D115176
This patch implements PAC return address signing for armv8-m. This patch roughly
accomplishes the following things:
- PAC and AUT instructions are generated.
- They're part of the stack frame setup, so that shrink-wrapping can move them
inwards to cover only part of a function
- The auth code generated by PAC is saved across subroutine calls so that AUT
can find it again to check
- PAC is emitted before stacking registers (so that the SP it signs is the one
on function entry).
- The new pseudo-register ra_auth_code is mentioned in the DWARF frame data
- With CMSE also in use: PAC is emitted before stacking FPCXTNS, and AUT
validates the corresponding value of SP
- Emit correct unwind information when PAC is replaced by PACBTI
- Handle tail calls correctly
Some notes:
We make the assembler accept the `.save {ra_auth_code}` directive that is
emitted by the compiler when it saves a register that contains a
return address authentication code.
For EHABI we need to have the `FrameSetup` flag on the instruction and
handle the `t2PACBTI` opcode (identically to `t2PAC`), so we can emit
`.save {ra_auth_code}`, instead of `.save {r12}`.
For PACBTI-M, the instruction which computes return address PAC should use SP
value before adjustment for the argument registers save are (used for variadic
functions and when a parameter is is split between stack and register), but at
the same it should be after the instruction that saves FPCXT when compiling a
CMSE entry function.
This patch moves the varargs SP adjustment after the FPCXT save (they are never
enabled at the same time), so in a following patch handling of the `PAC`
instruction can be placed between them.
Epilogue emission code adjusted in a similar manner.
PACBTI-M code generation should not emit any instructions for architectures
v6-m, v8-m.base, and for A- and R-class cores. Diagnostic message for such cases
is handled separately by a future ticket.
note on tail calls:
If the called function has four arguments that occupy registers `r0`-`r3`, the
only option for holding the function pointer itself is `r12`, but this register
is used to keep the PAC during function/prologue epilogue and clobbers the
function pointer.
When we do the tail call we need the five registers (`r0`-`r3` and `r12`) to
keep six values - the four function arguments, the function pointer and the PAC,
which is obviously impossible.
One option would be to authenticate the return address before all callee-saved
registers are restored, so we have a scratch register to temporarily keep the
value of `r12`. The issue with this approach is that it violates a fundamental
invariant that PAC is computed using CFA as a modifier. It would also mean using
separate instructions to pop `lr` and the rest of the callee-saved registers,
which would offset the advantages of doing a tail call.
Instead, this patch disables indirect tail calls when the called function take
four or more arguments and the return address sign and authentication is enabled
for the caller function, conservatively assuming the caller function would spill
LR.
This patch is part of a series that adds support for the PACBTI-M extension of
the Armv8.1-M architecture, as detailed here:
https://community.arm.com/arm-community-blogs/b/architectures-and-processors-blog/posts/armv8-1-m-pointer-authentication-and-branch-target-identification-extension
The PACBTI-M specification can be found in the Armv8-M Architecture Reference
Manual:
https://developer.arm.com/documentation/ddi0553/latest
The following people contributed to this patch:
- Momchil Velikov
- Ties Stuij
Reviewed By: danielkiss
Differential Revision: https://reviews.llvm.org/D112429
The v8.1-m ARMARM uses the vrinta.f16.f16 names, as opposed to
vrinta.f16. This adds an alias for it in the same way that we have for
f32 and f64.
Differential Revision: https://reviews.llvm.org/D68127
This adjusts all the MVE and CDE intrinsics now that v2i1 is a legal
type, to use a <2 x i1> as opposed to emulating the predicate with a
<4 x i1>. The v4i1 workarounds have been removed leaving the natural
v2i1 types, notably in vctp64 which now generates a v2i1 type.
AutoUpgrade code has been added to upgrade old IR, which needs to
convert the old v4i1 to a v2i1 be converting it back and forth to an
integer with arm.mve.v2i and arm.mve.i2v intrinsics. These should be
optimized away in the final assembly.
Differential Revision: https://reviews.llvm.org/D114455
MVE can treat v16i1, v8i1, v4i1 and v2i1 as different views onto the
same 16bit VPR.P0 register, with v2i1 holding two 8 bit values for the
two halves. This was never treated as a legal type in llvm in the past
as there are not many 64bit instructions and no 64bit compares. There
are a few instructions that could use it though, notably a VSELECT (as
it can handle any size using the underlying v16i8 VPSEL), AND/OR/XOR for
similar reasons, some gathers/scatter and long multiplies and VCTP64
instructions.
This patch goes through and makes v2i1 a legal type, handling all the
cases that fall out of that. It also makes VSELECT legal for v2i64 as a
side benefit. A lot of the codegen changes as a result - usually in way
that is a little better or a little worse, but still expensive. Costs
can change a little too in the process, again in a way that expensive
things remain expensive. A lot of the tests that changed are mainly to
ensure correctness - the code can hopefully be improved in the future
where it comes up in practice.
The intrinsics currently remain using the v4i1 they previously did to
emulate a v2i1. This will be changed in a followup patch but this one
was already large enough.
Differential Revision: https://reviews.llvm.org/D114449
Some instructions with i8 immediate ranges can only hold negative values
(like t2LDRHi8), only hold positive values (like t2STRT) or hold +/-
depending on the U bit (like the pre/post inc instructions. e.g
t2LDRH_POST). This patch splits the AddrModeT2_i8 into AddrModeT2_i8,
AddrModeT2_i8pos and AddrModeT2_i8neg to make this clear.
This allows us to get the offset ranges of t2LDRHi8 correct in the
load/store optimizer, fixing issues where we could end up creating
instructions with positive offsets (which may then be encoded as ldrht).
Differential Revision: https://reviews.llvm.org/D114638
The ranges in isLegalAddressImm were off by one, not allowing the
maximum values for unscaled offsets.
Differential Revision: https://reviews.llvm.org/D114636
Given a min(max(fptosi, INT_MIN), INT_MAX) with the correct constants,
we can now generate a fptosi.sat. But in the arm backend, the constant
can be treated as high cost, pulling it out of the basic block in a way
that the DAG combine can no longer see it. This teaches it again that it
is a low cost constant, not worth hoisting out.
Recommitted from 0e98659ea1 with a fix for APInt comparison.
Differential Revision: https://reviews.llvm.org/D114380
This patch implements a new MachineFunction in the ARM backend for
placing BTI instructions. It is similar to the existing AArch64
aarch64-branch-targets pass.
BTI instructions are inserted into basic blocks that:
- Have their address taken
- Are the entry block of a function, if the function has external
linkage or has its address taken
- Are mentioned in jump tables
- Are exception/cleanup landing pads
Each BTI instructions is placed in the beginning of a BB after the
so-called meta instructions (e.g. exception handler labels).
Each outlining candidate and the outlined function need to be in agreement about
whether BTI placement is enabled or not. If branch target enforcement is
disabled for a function, the outliner should not covertly enable it by emitting
a call to an outlined function, which begins with BTI.
The cost mode of the outliner is adjusted to account for the extra BTI
instructions in the outlined function.
The ARM Constant Islands pass will maintain the count of the jump tables, which
reference a block. A `BTI` instruction is removed from a block only if the
reference count reaches zero.
PAC instructions in entry blocks are replaced with PACBTI instructions (tests
for this case will be added in a later patch because the compiler currently does
not generate PAC instructions).
The ARM Constant Island pass is adjusted to handle BTI
instructions correctly.
Functions with static linkage that don't have their address taken can
still be called indirectly by linker-generated veneers and thus their
entry points need be marked with BTI or PACBTI.
The changes are tested using "LLVM IR -> assembly" tests, jump tables
also have a MIR test. Unfortunately it is not possible add MIR tests
for exception handling and computed gotos because of MIR parser
limitations.
This patch is part of a series that adds support for the PACBTI-M extension of
the Armv8.1-M architecture, as detailed here:
https://community.arm.com/arm-community-blogs/b/architectures-and-processors-blog/posts/armv8-1-m-pointer-authentication-and-branch-target-identification-extension
The PACBTI-M specification can be found in the Armv8-M Architecture Reference
Manual:
https://developer.arm.com/documentation/ddi0553/latest
The following people contributed to this patch:
- Mikhail Maltsev
- Momchil Velikov
- Ties Stuij
Reviewed By: ostannard
Differential Revision: https://reviews.llvm.org/D112426
This patch encapsulates decision logic about when and how to generate
PAC/BTI related code. It's a part shared by PAC-RET, BTI placement,
build attribute emission, etc, so it make sense committing it
separately in order to unblock the aforementioned parts, which can
proceed concurrently.
This patch adds a few member functions to `ARMFunctionInfo`, which are currently
unused, therefore there is no testing for them at the moment. This code is
tested in follow-up PAC/BTI code gen patches.
This patch is part of a series that adds support for the PACBTI-M extension of
the Armv8.1-M architecture, as detailed here:
https://community.arm.com/arm-community-blogs/b/architectures-and-processors-blog/posts/armv8-1-m-pointer-authentication-and-branch-target-identification-extension
The PACBTI-M specification can be found in the Armv8-M Architecture Reference
Manual:
https://developer.arm.com/documentation/ddi0553/latest
The following people contributed to this patch:
- Momchil Velikov
- Ties Stuij
Reviewed By: danielkiss
Differential Revision: https://reviews.llvm.org/D112423
Given a min(max(fptosi, INT_MIN), INT_MAX) with the correct constants,
we can now generate a fptosi.sat. But in the arm backend, the constant
can be treated as high cost, pulling it out of the basic block in a way
that the DAG combine can no longer see it. This teaches it again that it
is a low cost constant, not worth hoisting out.
Differential Revision: https://reviews.llvm.org/D114380
This adds a fold in DAGCombine to create fptosi_sat from sequences for
smin(smax(fptosi(x))) nodes, where the min/max saturate the output of
the fp convert to a specific bitwidth (say INT_MIN and INT_MAX). Because
it is dealing with smin(/smax) in DAG they may currently be ISD::SMIN,
ISD::SETCC/ISD::SELECT, ISD::VSELECT or ISD::SELECT_CC nodes which need
to be handled similarly.
A shouldConvertFpToSat method was added to control when converting may
be profitable. The original fptosi will have a less strict semantics
than the fptosisat, with less values that need to produce defined
behaviour.
This especially helps on ARM/AArch64 where the vcvt instructions
naturally saturate the result.
Differential Revision: https://reviews.llvm.org/D111976
It causes builds to fail with this assert:
llvm/include/llvm/ADT/APInt.h:990:
bool llvm::APInt::operator==(const llvm::APInt &) const:
Assertion `BitWidth == RHS.BitWidth && "Comparison requires equal bit widths"' failed.
See comment on the code review.
> This adds a fold in DAGCombine to create fptosi_sat from sequences for
> smin(smax(fptosi(x))) nodes, where the min/max saturate the output of
> the fp convert to a specific bitwidth (say INT_MIN and INT_MAX). Because
> it is dealing with smin(/smax) in DAG they may currently be ISD::SMIN,
> ISD::SETCC/ISD::SELECT, ISD::VSELECT or ISD::SELECT_CC nodes which need
> to be handled similarly.
>
> A shouldConvertFpToSat method was added to control when converting may
> be profitable. The original fptosi will have a less strict semantics
> than the fptosisat, with less values that need to produce defined
> behaviour.
>
> This especially helps on ARM/AArch64 where the vcvt instructions
> naturally saturate the result.
>
> Differential Revision: https://reviews.llvm.org/D111976
This reverts commit 52ff3b0093.
This adds a fold in DAGCombine to create fptosi_sat from sequences for
smin(smax(fptosi(x))) nodes, where the min/max saturate the output of
the fp convert to a specific bitwidth (say INT_MIN and INT_MAX). Because
it is dealing with smin(/smax) in DAG they may currently be ISD::SMIN,
ISD::SETCC/ISD::SELECT, ISD::VSELECT or ISD::SELECT_CC nodes which need
to be handled similarly.
A shouldConvertFpToSat method was added to control when converting may
be profitable. The original fptosi will have a less strict semantics
than the fptosisat, with less values that need to produce defined
behaviour.
This especially helps on ARM/AArch64 where the vcvt instructions
naturally saturate the result.
Differential Revision: https://reviews.llvm.org/D111976
We can't use the existing pseudo ARM::tLDRLIT_ga_pcrel for loading the
stack guard for PIC code that references the GOT, since arm-pseudo may
expand this to the narrow tLDRpci rather than the wider t2LDRpci.
Create a new pseudo, t2LDRLIT_ga_pcrel, and expand it to t2LDRpci.
Fixes: https://bugs.chromium.org/p/chromium/issues/detail?id=1270361
Reviewed By: ardb
Differential Revision: https://reviews.llvm.org/D114762
We sometimes end up generating CMOV with constant operands that can be
simplified to CSINC or CSINV under Arm-8.1m. This adds some simple
patterns for them.
Differential Revision: https://reviews.llvm.org/D114349
Codegen from expanded vector operations can end up with unnecessary
CMPZ/CSINC, of the form:
CSXYZ A, B, C1 (CMPZ (CSINC 0, 0, C2, D), 0)
These can be converted to remove the CMPZ and CSINC, depending on the
condition.
if C1==NE -> CSXYZ A, B, C2, D
if C1==EQ -> CSXYZ A, B, NOT(C2), D
Differential Revision: https://reviews.llvm.org/D114013
This converts a vector SETCC([0,1,2,..], splat(n), ult) to vctp n, which
can be fewer instructions and prevent the need for constant pool loads.
Differential Revision: https://reviews.llvm.org/D114177
This is a very small addition to the existing MVE fixed point vcvt code
to also create them from FP_TO_SINT_SAT and FP_TO_UINT_SAT nodes, which
should be equally valid for native saturating converts under MVE.
Differential Revision: https://reviews.llvm.org/D114360
If we only demand bits from one half of a rotation pattern, see if we can simplify to a logical shift.
For the ARM/AArch64 rev16/32 patterns, I had to drop a fold to prevent srl(bswap()) -> rotr(bswap) -> srl(bswap) infinite loops. I've replaced this with an isel PatFrag which should do the same task.
Reapplied with fix for AArch64 rev patterns to matching the ARM fix.
https://alive2.llvm.org/ce/z/iroxki (rol -> shl by amt iff demanded bits has at least as many trailing zeros as the shift amount)
https://alive2.llvm.org/ce/z/4ez_U- (ror -> shl by revamt iff demanded bits has at least as many trailing zeros as the reverse shift amount)
https://alive2.llvm.org/ce/z/cD7dR- (ror -> lshr by amt iff demanded bits has at least as many leading zeros as the shift amount)
https://alive2.llvm.org/ce/z/_XGHtQ (rol -> lshr by revamt iff demanded bits has at least as many leading zeros as the reverse shift amount)
Differential Revision: https://reviews.llvm.org/D114354
If we only demand bits from one half of a rotation pattern, see if we can simplify to a logical shift.
For the ARM rev16 patterns, I had to drop a fold to prevent srl(bswap()) -> rotr(bswap) -> srl(bswap) infinite loops. I've replaced this with an isel PatFrag which should do the same task.
https://alive2.llvm.org/ce/z/iroxki (rol -> shl by amt iff demanded bits has at least as many trailing zeros as the shift amount)
https://alive2.llvm.org/ce/z/4ez_U- (ror -> shl by revamt iff demanded bits has at least as many trailing zeros as the reverse shift amount)
https://alive2.llvm.org/ce/z/cD7dR- (ror -> lshr by amt iff demanded bits has at least as many leading zeros as the shift amount)
https://alive2.llvm.org/ce/z/_XGHtQ (rol -> lshr by revamt iff demanded bits has at least as many leading zeros as the reverse shift amount)
Differential Revision: https://reviews.llvm.org/D114354
This is similar to D113574, but as a DAG combine, not tablegen patterns.
Doing the fold as a DAG combine allows the fadd to be folded with a
fmul, finally producing a predicated vfma. It performs the same fold of
fadd(x, vselect(p, y, -0.0)) to vselect p, (fadd x, y), x) using -0.0 as
the identity value of a fadd.
Differential Revision: https://reviews.llvm.org/D113584
Similar to D84091 which added extra predicated folds for integer operations
using the identity element of the operation, this adds them for floating
point operations for the form `BinOp(x, select(p, y, Identity))`. They are
folded back to predicated versions of the operator, with fadd having the
identity -0.0, fsub using the identity 0.0 and fmul using 1.0.
Differential Revision: https://reviews.llvm.org/D113574
[NFC] As part of using inclusive language within the llvm project, this patch
replaces master with main in `Thumb2SizeReduction.cpp`.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D114196
Delegate updating of LiveIntervals to each target's
convertToThreeAddress implementation, instead of repairing LiveIntervals
after the fact in TwoAddressInstruction::convertInstTo3Addr.
Differential Revision: https://reviews.llvm.org/D113493
Implement support for loading the stack canary from a memory location held in
the TLS register, with an optional offset applied. This is used by the Linux
kernel to implement per-task stack canaries, which is impossible on SMP systems
when using a global variable for the stack canary.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D112768
Currently, LOAD_STACK_GUARD on ARM is only implemented for Mach-O targets, and
other targets rely on the generic support which may result in spilling of the
stack canary value or address, or may cause it to be kept in a callee save
register across function calls, which means they essentially get spilled as
well, only by the callee when it wants to free up this register.
So let's implement LOAD_STACK GUARD for other targets as well. This ensures
that the load of the stack canary is rematerialized fully in the epilogue.
This code was split off from
D112768: [ARM] implement support for TLS register based stack protector
for which it is a prerequisite.
Reviewed By: nickdesaulniers
Differential Revision: https://reviews.llvm.org/D112811
Currently when tail predicating loops, vpt blocks need to be created
with the vctp predicate in case we need to revert to non-tail predicated
form. This has the unfortunate side effect of severely hampering post-ra
scheduling at times as the instructions are already stuck in vpt blocks,
not allowed to be independently ordered.
This patch addresses that by just moving the creation of VPT blocks
later in the pipeline, after post-ra scheduling has been performed. This
allows more optimal scheduling post-ra before the vpt blocks are
created, leading to more optimal tail predicated loops.
Differential Revision: https://reviews.llvm.org/D113094
LLVM has the habit of turning adds with no common bits set into ors,
which means we need to detect them and treat them like adds again in the
MVE gather/scatter lowering pass.
Differential Revision: https://reviews.llvm.org/D112922
This teaches the MVE gather scatter lowering pass that SHL is
essentially the same as Mul, where we are able to optimize the
induction of a gather/scatter address by pushing them out of loops.
https://alive2.llvm.org/ce/z/wG4VyT
Differential Revision: https://reviews.llvm.org/D112920
This is relanding commit da1d1a0869 .
This patch additionally addresses failures found in buildbots & post review comments.
ARM EHABI[1] specifies the __cxa_end_cleanup to be called after cleanup.
It will call the UnwindResume.
__cxa_begin_cleanup will be called from libcxxabi while __cxa_end_cleanup is never called.
This will trigger a termination when a foreign exception is processed while UnwindResume is called
because the global state will be wrong due to the missing __cxa_end_cleanup call.
Additional test here: D109856
[1] https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst#941compiler-helper-functions
Reviewed By: logan
Differential Revision: https://reviews.llvm.org/D111703
This is relanding commit da1d1a0869 .
This patch additionally addresses failures found in buildbots & post review comments.
ARM EHABI[1] specifies the __cxa_end_cleanup to be called after cleanup.
It will call the UnwindResume.
__cxa_begin_cleanup will be called from libcxxabi while __cxa_end_cleanup is never called.
This will trigger a termination when a foreign exception is processed while UnwindResume is called
because the global state will be wrong due to the missing __cxa_end_cleanup call.
Additional test here: D109856
[1] https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst#941compiler-helper-functions
Reviewed By: logan
Differential Revision: https://reviews.llvm.org/D111703
In ARM mode, passing -mtp=cp15 forces the use of an inline MRC system register read to move the thread pointer value into a register.
Currently, in Thumb2 mode, -mtp=cp15 is ignored, and a call to the __aeabi_read_tp helper is emitted instead.
This is inconsistent, and breaks the Linux/ARM build for Thumb2 targets, as the Linux kernel does not provide an implementation of __aeabi_read_tp,.
Reviewed By: nickdesaulniers, peter.smith
Differential Revision: https://reviews.llvm.org/D112600
ARM EHABI[1] specifies the __cxa_end_cleanup to be called after cleanup.
It will call the UnwindResume.
__cxa_begin_cleanup will be called from libcxxabi while __cxa_end_cleanup is never called.
This will trigger a termination when a foreign exception is processed while UnwindResume is called
because the global state will be wrong due to the missing __cxa_end_cleanup call.
Additional test here: D109856
[1] https://github.com/ARM-software/abi-aa/blob/main/ehabi32/ehabi32.rst#941compiler-helper-functions
Reviewed By: logan
Differential Revision: https://reviews.llvm.org/D111703
Instead of returning a bool to indicate success and a separate
SDValue, return the SDValue and have the callers check if it is
null.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D112331
Inspired by D111968, provide a isNegatedPowerOf2() wrapper instead of obfuscating code with (-Value).isPowerOf2() patterns, which I'm sure are likely avenues for typos.....
Differential Revision: https://reviews.llvm.org/D111998
When compiling for the RWPI relocation model the debug information is wrong:
* the debug location is described as { DW_OP_addr Var }
instead of { DW_OP_constNu Var DW_OP_bregX 0 DW_OP_plus }
* the relocation type is R_ARM_ABS32 instead of R_ARM_SBREL32
Differential Revision: https://reviews.llvm.org/D111404
The MOVCC peephole eliminates a MOVCC by making one of its inputs a
conditional instruction, but when doing this it should be using both
inputs of the MOVCC to decide on the register class to use as
otherwise we can get an error when using -verify-machineinstrs.
Differential Revision: https://reviews.llvm.org/D111714
The patch attempts to optimize a sequence of SIMD loads from the same
base pointer:
%0 = gep float*, float* base, i32 4
%1 = bitcast float* %0 to <4 x float>*
%2 = load <4 x float>, <4 x float>* %1
...
%n1 = gep float*, float* base, i32 N
%n2 = bitcast float* %n1 to <4 x float>*
%n3 = load <4 x float>, <4 x float>* %n2
For AArch64 the compiler generates a sequence of LDR Qt, [Xn, #16].
However, 32-bit NEON VLD1/VST1 lack the [Wn, #imm] addressing mode, so
the address is computed before every ld/st instruction:
add r2, r0, #32
add r0, r0, #16
vld1.32 {d18, d19}, [r2]
vld1.32 {d22, d23}, [r0]
This can be improved by computing address for the first load, and then
using a post-indexed form of VLD1/VST1 to load the rest:
add r0, r0, #16
vld1.32 {d18, d19}, [r0]!
vld1.32 {d22, d23}, [r0]
In order to do that, the patch adds more patterns to DAGCombine:
- (load (add ptr inc1)) and (add ptr inc2) are now folded if inc1
and inc2 are constants.
- (or ptr inc) is now recognized as a pointer increment if ptr is
sufficiently aligned.
In addition to that, we now search for all possible base updates and
then pick the best one.
Differential Revision: https://reviews.llvm.org/D108988
This shouldn't be called for non-neon targets at the moment in either
case, but it is good to be expliit about the CombineBaseUpdate being a
NEON function, not expecting to be run under MVE.
armv9-a, armv9.1-a and armv9.2-a can be targeted using the -march option
both in ARM and AArch64.
- Armv9-A maps to Armv8.5-A.
- Armv9.1-A maps to Armv8.6-A.
- Armv9.2-A maps to Armv8.7-A.
- The SVE2 extension is enabled by default on these architectures.
- The cryptographic extensions are disabled by default on these
architectures.
The Armv9-A architecture is described in the Arm® Architecture Reference
Manual Supplement Armv9, for Armv9-A architecture profile
(https://developer.arm.com/documentation/ddi0608/latest).
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D109517
This moves the registry higher in the LLVM library dependency stack.
Every client of the target registry needs to link against MC anyway to
actually use the target, so we might as well move this out of Support.
This allows us to ensure that Support doesn't have includes from MC/*.
Differential Revision: https://reviews.llvm.org/D111454
Currently when creating tail predicated loops, we need to validate that
all the live-outs of a loop will be equivalent with and without tail
predication, and if they are not we cannot legally create a
tail-predicated loop, leaving expensive vctp and vpst instructions in
the loop. These notably can include register-allocation instructions
like stack loads and stores, and copys lowered from COPYs to MVE_VORRs.
Instead of trying to prove this is valid late in the pipeline, this
patch introduces a MQPRCopy pseudo instruction that COPY is lowered to.
This can then either be converted to a MVE_VORR where possible, or to a
couple of VMOVD instructions if not. This way they do not behave
differently within and outside of tail-predications regions, and we can
know by construction that they are always valid. The idea is that we can
do the same with stack load and stores, converting them to VLDR/VSTR or
VLDM/VSTM where required to prove tail predication is always valid.
This does unfortunately mean inserting multiple VMOVD instructions,
instead of a single MVE_VORR, but my experiments show it to be an
improvement in general.
Differential Revision: https://reviews.llvm.org/D111048
To better reflect the meaning of the now-disambiguated {GlobalValue,
GlobalAlias}::getBaseObject after breaking off GlobalIFunc::getResolverFunction
(D109792), the function is renamed to getAliaseeObject.
D100244 missed a check on the ResNo of the extract's operand 0 when finding a
pair of extracts to combine into a VMOVRRD (extract(x, n); extract(x, n+1) ->
VMOVRRD(extract x, n/2)). As a result, it can incorrectly pair an extract(x, n)
with another extract(x:3, n+1) for example. This patch fixes the bug by adding
the proper check on ResNo.
Reviewed By: dmgreen
Differential Revision: https://reviews.llvm.org/D111188
The delayed stack protector feature which is currently used for SDAG (and thus
allows for more commonly generating tail calls) depends on being able to extract
the tail call into a separate return block. To do this it also has to extract
the vreg->physreg copies that set up the call's arguments, since if it doesn't
then the call inst ends up using undefined physregs in it's new spliced block.
SelectionDAG implementations can do this because they delay emitting register
copies until *after* the stack arguments are set up. GISel however just
processes and emits the arguments in IR order, so stack arguments always end up
last, and thus this breaks the code that looks for any register arg copies that
precede the call instruction.
This patch adds a thunk argument to the assignValueToReg() and custom assignment
hooks. For outgoing arguments, register assignments use this return param to
return a thunk that does the actual generating of the copies. We collect these
until all the outgoing stack assignments have been done and then execute them,
so that the copies (and perhaps some artifacts like G_SEXTs) are placed after
any stores.
Differential Revision: https://reviews.llvm.org/D110610
Stop using APInt constructors and methods that were soft-deprecated in
D109483. This fixes all the uses I found in llvm, except for the APInt
unit tests which should still test the deprecated methods.
Differential Revision: https://reviews.llvm.org/D110807
A <= -1 constant on a compare can be converted to a < 0 operation, which
is usually cheap. If we mark the constant as cheap, preventing hoisting,
we allow that fold to happen even across different blocks.
Differential Revision: https://reviews.llvm.org/D109360
This adds a few more unpredicated intrinsics to sink splats to, in order
to create more qr instruction variants. Notably this includes
saddsat/uaddsat but also some of the unpredicated mve intrinsics.
Differential Revision: https://reviews.llvm.org/D110333
As we have to split blocks, we may be left in an invalid loop state
after a WLS is reverted to a DLS. Instead remember the WLS that could
not be fixed and revert them after finishing processing all other loops.
Differential Revision: https://reviews.llvm.org/D110567
The ARMLowOverheadLoops pass recalculates VPT block masks when it
converts VCMP's inside VPT blocks into VPT's. The function to do so
doesn't seem to handle debug info though, leading to invalid block
creation or asserts at compile time. Make sure the function skips any
debug info between the MVE instructions it inspects.
Differential Revision: https://reviews.llvm.org/D110564
We align non-fallthrough branches under Cortex-M at O3 to lead to fewer
instruction fetches. This improves that for the block after a LE or
LETP. These blocks will still have terminating branches until the
LowOverheadLoops pass is run (as they are not handled by analyzeBranch,
the branch is not removed until later), so canFallThrough will return
false. These extra branches will eventually be removed, leaving a
fallthrough, so treat them as such and don't add unnecessary alignments.
Differential Revision: https://reviews.llvm.org/D107810
Given:
- A jump table
- Which jumps to the next block
- The next block ends in a WLS
- Where the WLS conditionally jumps to block earlier in the program.
The Arm block placement pass would attempt to move the block containing
the WLS earlier, as the WLS instruction can only branch forward. In
doing so it would add a branch from the jumptable block to the WLS
block, thinking it previously fell-through.
This in itself would be fine, if a little inefficient, but the constant
island pass expects all instructions after a jump-table branch to have
been removed by analyzeBranch. So it gets confused and can assign the
same labels to multiple jump table blocks.
I've changed the condition to the same as used in analyzeBranch.
This simplifies the API and addresses a FIXME in
TwoAddressInstructionPass::convertInstTo3Addr.
Differential Revision: https://reviews.llvm.org/D110229
Based off a discussion on D110100, we should be avoiding default CostKinds whenever possible.
This initial patch removes them from the 'inner' target implementation callbacks - these should only be used by the main TTI calls, so this should guarantee that we don't cause changes in CostKind by missing it in an inner call. This exposed a few missing arguments in getGEPCost and reduction cost calls that I've cleaned up.
Differential Revision: https://reviews.llvm.org/D110242
This allows VMOVL in tail predicated loops so long as the the vector
size the VMOVL is extending into is less than or equal to the size of
the VCTP in the tail predicated loop. These cases represent a
sign-extend-inreg (or zero-extend-inreg), which needn't block tail
predication as in https://godbolt.org/z/hdTsEbx8Y.
For this a vecsize has been added to the TSFlag bits of MVE
instructions, which stores the size of the elements that the MVE
instruction operates on. In the case of multiple size (such as a
MVE_VMOVLs8bh that extends from i8 to i16, the largest size was be
chosen). The sizes are encoded as 00 = i8, 01 = i16, 10 = i32 and 11 =
i64, which often (but not always) comes from the instruction encoding
directly. A unit test was added, and although only a subset of the
vecsizes are currently used, the rest should be useful for other cases.
Differential Revision: https://reviews.llvm.org/D109706
The vectorizer can sometimes make reverse shuffles from indices that
count down. In MVE, we don't have a 128bit rev instruction, but we can
select this to a VREV64 with some lane movs to swap the two halfs.
Ideally this would use VMOVD's, but only gets as far as VMOVS's at the
moment.
Differential Revision: https://reviews.llvm.org/D69510
Recently a vulnerability issue is found in the implementation of VLLDM
instruction in the Arm Cortex-M33, Cortex-M35P and Cortex-M55. If the
VLLDM instruction is abandoned due to an exception when it is partially
completed, it is possible for subsequent non-secure handler to access
and modify the partial restored register values. This vulnerability is
identified as CVE-2021-35465.
The mitigation sequence varies between v8-m and v8.1-m as follows:
v8-m.main
---------
mrs r5, control
tst r5, #8 /* CONTROL_S.SFPA */
it ne
.inst.w 0xeeb00a40 /* vmovne s0, s0 */
1:
vlldm sp /* Lazy restore of d0-d16 and FPSCR. */
v8.1-m.main
-----------
vscclrm {vpr} /* Clear VPR. */
vlldm sp /* Lazy restore of d0-d16 and FPSCR. */
More details on
developer.arm.com/support/arm-security-updates/vlldm-instruction-security-vulnerability
Differential Revision: https://reviews.llvm.org/D109157
When expanding the non-secure call instruction we are emiting code
to clear the secure floating-point registers only if the targeted
architecture has floating-point support. The potential problem is
when the source code containing non-secure calls are built with
-mfloat-abi=soft but some other part of the system has been built
with -mfloat-abi=softfp (soft and softfp are compatible as they use
the same procedure calling standard). In this case floating-point
registers could leak to non-secure state as the non-secure won't
have cleared them assuming no floating point has been used.
Differential Revision: https://reviews.llvm.org/D109153
Under some situations under Thumb1, we could be stuck in an infinite
loop recombining the same instruction. This puts a limit on that, not
combining SUBC with SUBE repeatedly.
The class of instructions that write to narrow top/bottom lanes only
demand the even or odd elements of the input lanes. Which means that a
pair of VMOVNT; VMOVNB demands no lanes from the original input. This
teaches that to instcombine from the target hooks available through
ARMTTIImpl.
Differential Revision: https://reviews.llvm.org/D109325
Pass the access type to getPtrStride(), so it is not determined
from the pointer element type. Many cases still fetch the element
type at a higher level though, so this only partially addresses
the issue.
When passing an empty strides map, there's nothing to replace for
replaceSymbolicStrideSCEV and it just returns the SCEV for Ptr. There
should be no need to call the function.
Reviewed By: SjoerdMeijer
Differential Revision: https://reviews.llvm.org/D109462
Soft deprecrate isNullValue/isAllOnesValue and update in tree
callers. This matches the changes to the APInt interface from
D109483.
Reviewed By: lattner
Differential Revision: https://reviews.llvm.org/D109535
This renames the primary methods for creating a zero value to `getZero`
instead of `getNullValue` and renames predicates like `isAllOnesValue`
to simply `isAllOnes`. This achieves two things:
1) This starts standardizing predicates across the LLVM codebase,
following (in this case) ConstantInt. The word "Value" doesn't
convey anything of merit, and is missing in some of the other things.
2) Calling an integer "null" doesn't make any sense. The original sin
here is mine and I've regretted it for years. This moves us to calling
it "zero" instead, which is correct!
APInt is widely used and I don't think anyone is keen to take massive source
breakage on anything so core, at least not all in one go. As such, this
doesn't actually delete any entrypoints, it "soft deprecates" them with a
comment.
Included in this patch are changes to a bunch of the codebase, but there are
more. We should normalize SelectionDAG and other APIs as well, which would
make the API change more mechanical.
Differential Revision: https://reviews.llvm.org/D109483
On some architectures such as Arm and X86 the encoding for a nop may
change depending on the subtarget in operation at the time of
encoding. This change replaces the per module MCSubtargetInfo retained
by the targets AsmBackend in favour of passing through the local
MCSubtargetInfo in operation at the time.
On Arm using the architectural NOP instruction can have a performance
benefit on some implementations.
For Arm I've deleted the copy of the AsmBackend's MCSubtargetInfo to
limit the chances of this causing problems in the future. I've not
done this for other targets such as X86 as there is more frequent use
of the MCSubtargetInfo and it looks to be for stable properties that
we would not expect to vary per function.
This change required threading STI through MCNopsFragment and
MCBoundaryAlignFragment.
I've attempted to take into account the in tree experimental backends.
Differential Revision: https://reviews.llvm.org/D45962
In preparation for passing the MCSubtargetInfo (STI) through to writeNops
so that it can use the STI in operation at the time, we need to record the
STI in operation when a MCAlignFragment may write nops as padding. The
STI is currently unused, a further patch will pass it through to
writeNops.
There are many places that can create an MCAlignFragment, in most cases
we can find out the STI in operation at the time. In a few places this
isn't possible as we are in initialisation or finalisation, or are
emitting constant pools. When possible I've tried to find the most
appropriate existing fragment to obtain the STI from, when none is
available use the per module STI.
For constant pools we don't actually need to use EmitCodeAlign as the
constant pools are data anyway so falling through into it via an
executable NOP is no better than falling through into data padding.
This is a prerequisite for D45962 which uses the STI to emit the
appropriate NOP for the STI. Which can differ per fragment.
Note that involves an interface change to InitSections. It is now
called initSections and requires a SubtargetInfo as a parameter.
Differential Revision: https://reviews.llvm.org/D45961
As an extension to D107866, this adds store(fptosisat(..)) patterns,
similar to the existing fptosi patterns, to prevent unnecessarily moving
into gpr regs where we can use fp stores directly.
Differential Revision: https://reviews.llvm.org/D108378
This extends D107865 to the VFP insructions, lowering llvm.fptosi.sat
and llvm.fptoui.sat to VCVT instructions that inherently perform the
saturate.
Differential Revision: https://reviews.llvm.org/D107866
The semantics of tail predication loops means that the value of LR as an
instruction is executed determines the predicate. In other words:
mov r3, #3
DLSTP lr, r3 // Start tail predication, lr==3
VADD.s32 q0, q1, q2 // Lanes 0,1 and 2 are updated in q0.
mov lr, #1
VADD.s32 q0, q1, q2 // Only first lane is updated.
This means that the value of lr cannot be spilled and re-used in tail
predication regions without potentially altering the behaviour of the
program. More lanes than required could be stored, for example, and in
the case of a gather those lanes might not have been setup, leading to
alignment exceptions.
This patch adds a new lr predicate operand to MVE instructions in order
to keep a reference to the lr that they use as a tail predicate. It will
usually hold the zeroreg meaning not predicated, being set to the LR phi
value in the MVETPAndVPTOptimisationsPass. This will prevent it from
being spilled anywhere that it needs to be used.
A lot of tests needed updating.
Differential Revision: https://reviews.llvm.org/D107638
This adds lowering of the llvm.fptosi.sat and llvm.fptoui.sat intinsics,
selecting a VCVT instruction which under MVE will inherently perform the
saturate.
Differential Revision: https://reviews.llvm.org/D107865
This extends D108921 into a generic rule applied to constructing ExitLimits along all paths. The remaining paths (primarily howFarToZero) don't have the same reasoning about UB sensitivity as the howManyLessThan ones did. Instead, the remain cause for max counts being more precise than exact counts is that we apply context sensitive loop guards on the max path, and not on the exact path. That choice is mildly suspect, but out of scope of this patch.
The MVETailPredication.cpp change deserves a bit of explanation. We were previously figuring out that two SCEVs happened to be equal because the happened to be identical. When we optimized one with context sensitive information, but not the other, we lost the ability to prove them equal. So, cover this case by subtracting and then applying loop guards again. Without this, we see changes in test/CodeGen/Thumb2/mve-blockplacement.ll
Differential Revision: https://reviews.llvm.org/D109015
Add assert to provoke failure in object file output, not just in disassembly output.
Reviewed By: yroux
Differential Revision: https://reviews.llvm.org/D107259
The min/max intrinsics are not yet canonical, but when they are the tail
predications analysis will change from treating them like icmp to
treating them like intrinsics. Unfortunately, they can currently produce
better code by not being tail predicated thanks to the vectorizer picking
higher VF's and the backend folding to better instructions (especially
for saturate patterns). In the long run we will need to improve the
vectorizers cost modelling, recognizing the instruction directly, but in
the meantime this treats min/max as before to prevent performance
regressions.
The backend generally uses 64-bit immediates (e.g. what
MachineOperand::getImm() returns), so use that for analyzeCompare()
and optimizeCompareInst() as well. This avoids truncation for
targets that support immediates larger 32-bit. In particular, we
can avoid the bugprone value normalization hack in the AArch64
target.
This is a followup to D108076.
Differential Revision: https://reviews.llvm.org/D108875
__has_builtin(__builtin_mul_overflow) returns true for 32b ARM targets,
but Clang is deferring to compiler RT when encountering `long long`
types. This breaks sanitizer builds of the Linux kernel that are using
__builtin_mul_overflow with these types for these targets.
If the semantics of __has_builtin mean "the compiler resolves these,
always" then we shouldn't conditionally emit a libcall.
This will still need to be worked around in the Linux kernel in order to
continue to support allmodconfig builds of the Linux kernel for this
target with older releases of clang.
Link: https://bugs.llvm.org/show_bug.cgi?id=28629
Link: https://github.com/ClangBuiltLinux/linux/issues/1438
Reviewed By: rengolin
Differential Revision: https://reviews.llvm.org/D108842
This does the same as D96259, but for ARM, just like AArch64,
using the same comment char as for ELF and MinGW mode.
As the assembly input/output of LLVM is GAS style, trying to
match what MS armasm.exe does isn't needed (because the comment
char used is the least concern when it comes to that; all
directives differ too). If a separate armasm compatible mode
is implemented, it can use its own comment style (just like
llvm-ml implements MS ml.exe compatible assembly parsing).
This fixes building compiler-rt assembly files for ARM in MSVC
mode.
The updated testcase literals-comments.s was only intended to
make sure that '#' isn't interpreted as a comment char.
Differential Revision: https://reviews.llvm.org/D107251
Add a variant of mve-vqdmulh tests that uses min/max intrinsics
directly, including a scalar test that shows it misbehaving for min
intrinsics and a fix for the combine to prevent it from misbehaving.
This enables subreg liveness in the arm backend when MVE is present,
which allows the register allocator to detect when subregister are
alive/dead, compared to only acting on full registers. This can helps
produce better code on MVE with the way MQPR registers are made up of
SPR registers, but is especially helpful for MQQPR and MQQQQPR
registers, where there are very few "registers" available and being able
to split them up into subregs can help produce much better code.
Differential Revision: https://reviews.llvm.org/D107642
As a part of D107642, this adds pseudo instructions for MQQPR and
MQQQQPR register classes, that can spill and reloads entire registers
whilst keeping them combined, not splitting them into multiple D subregs
that a VLDMIA/VSTMIA would use. This can help certain analyses, and
helps to prevent verifier issues with subreg liveness.
Similar to the MQPR register class as the MVE equivalent to QPR, this
adds MQQPR and MQQQQPR register classes for the MVE equivalents of QQPR
and QQQQPR registers. The MVE MQPR seemed have worked out quite well,
and adding MQQPR and MQQQQPR allows us to a little more accurately
specify the number of registers, calculating register pressure limits a
little better.
Differential Revision: https://reviews.llvm.org/D107463
Follow-up to D107068, attempt to fold nested concat_vectors/undefs, as long as both the vector and inner subvector types are legal.
This exposed the same issue in ARM's MVE LowerCONCAT_VECTORS_i1 (raised as PR51365) and AArch64's performConcatVectorsCombine which both assumed concat_vectors only took 2 subvector operands.
Differential Revision: https://reviews.llvm.org/D107597
Given a constant operand, the MVE and DAGCombine combines could fight,
each redistributing in the opposite order. Add a guard to the MVE
vecreduce distribution to prevent that.
We are running into more and more cases where the liveouts of low
overhead loops do not validate. Add some extra debug messages to make it
clearer why.
This changes a couple of calls to LiveRegs.contains to
!LiveRegs.available, one in Thumb1FrameLoweringInfo (which modifies a
test to look more correct to me, given r7 should be the frame pointer so
is not available), and another in the ARMLoadStoreOptimizer, that I
don't have a test for, it was just found by inspection.
Differential Revision: https://reviews.llvm.org/D107454
Some of the Arm complex pattern functions call canExtractShiftFromMul,
which can modify the DAG in-place. For this to be valid and handled
successfully we need to define ComplexPatternFuncMutatesDAG.
Differential Revision: https://reviews.llvm.org/D107476
D107068 fixed the same problem on aarch64 but the arm variant wasn't exposed in existing test coverage.
I've copied the arm64-neon-copy tests (and stripped the intrinsic test from it) for testing on arm neon builds as well.
I just hit a nasty bug when writing a unit test after calling MF->getFrameInfo()
without declaring the variable as a reference.
Deleting the copy-constructor also showed a place in the ARM backend which was
doing the same thing, albeit it didn't impact correctness there from the looks of it.
This implements `MCInstrAnalysis::evaluateMemoryOperandAddress()` for
Arm so that the disassembler can print the target address of memory
operands that use PC+immediate addressing.
Differential Revision: https://reviews.llvm.org/D105979
This assert is intended to ensure that the high registers are not
selected when it is passed to one of the thumb UXT instructions. However
it was triggering even for 32 bit where no UXT instruction is emitted.
Fixes PR51313.
Differential Revision: https://reviews.llvm.org/D107363
Previously we would emit constant pool entries for ldr inline asm at the
very end of AsmPrinter::doFinalization(). However, if we're emitting
dwarf aranges, that would end all sections with aranges. Then if we have
constant pool entries to be emitted in those same sections, we'd hit an
assert that the section has already been ended.
We want to emit constant pool entries before emitting dwarf aranges.
This patch splits out arm32/64's constant pool entry emission into its
own MCTargetStreamer virtual method.
Fixes PR51208
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D107314
I'm not sure this is the best way to approach this,
but the situation is rather not very detectable unless we explicitly call it out when refusing to advise to unroll.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D107271
If the block target for a WLSTP instruction is known to be out of range,
and cannot be fixed by the ARMBlockPlacementPass, we can relax it to a
DLSTP (and cmp/branch) to still allow the creation of tail predicated
loops. That is what this patch does, adding extra revert code to the
fallback path of ARMBlockPlacementPass.
Due to the code produced when reverting, this creates a DLSTP between a
Bcc and a Br. As a DLS isn't necessarily a terminator we need to split
the block to move the DLS/Br into.
Differential Revision: https://reviews.llvm.org/D104709
This distributes reductions based on the relative offset of loads, if
one is found from their operands. Given chains of reductions this will
then sort them in ascending load order, which in turn can help simple
prefetches latch on to increasing strides more easily.
Differential Revision: https://reviews.llvm.org/D106569
This adds a combine for adds of reductions, distributing them so that
they occur sequentially to enable better use of accumulating VADDVA
instructions. It combines:
add(X, add(vecreduce(Y), vecreduce(Z))) ->
add(add(X, vecreduce(Y)), vecreduce(Z))
and
add(add(A, reduce(B)), add(C, reduce(D))) ->
add(add(add(A, C), reduce(B)), reduce(D))
These together distribute the add's so that more reductions can be
selected to VADDVA.
Differential Revision: https://reviews.llvm.org/D106532
Under MVE we can use VADDV/VADDVA's to perform integer add reductions,
so it can be beneficial to use more reductions than summing subvectors
and reducing once. Especially for VMLAV/VMLAVA the mul can be
incorporated into the reduction, producing less instructions.
Some of the test cases currently get larger due to extra integer adds,
but will be improved in a followup patch.
Differential Revision: https://reviews.llvm.org/D106531
Same as 91bd3ad128, this doesn't really
change anything but gives the registers better names than the ones
tablegen would define. And fills in the missing gaps.
This makes a couple of changes to the costing of MLA reduction patterns,
to more accurately cost various patterns that can come up from
vectorization.
- The Arm implementation of getExtendedAddReductionCost is altered to
only provide costs for legal or smaller types. Larger than legal types
need to be split, which currently does not work very well, especially
for predicated reductions where the predicate may be legal but needs to
be split. Currently we limit it to legal or smaller input types.
- The getReductionPatternCost has learnt that reduce(ext(mul(ext, ext))
is a pattern that can come up, and can be treated the same as
reduce(mul(ext, ext)) providing the extension types match.
- And it has been adjusted to not count the ext in reduce(mul(ext, ext))
as part of a reduce(mul) pattern.
Together these changes help to more accurately cost the mla reductions
in cases such as where the extend types don't match or the extend
opcodes are different, picking better vector factors that don't result
in expanded reductions.
Differential Revision: https://reviews.llvm.org/D106166
- This patch consists of the bare basic code needed in order to generate some assembly for the z/OS target.
- Only the .text and the .bss sections are added for now.
- The relevant MCSectionGOFF/Symbol interfaces have been added. This enables us to print out the GOFF machine code sections.
- This patch enables us to add simple lit tests wherever possible, and contribute to the testing coverage for the z/OS target
- Further improvements and additions will be made in future patches.
Reviewed By: tmatheson
Differential Revision: https://reviews.llvm.org/D106380
This implements the isLoadFromStackSlot and isStoreToStackSlot for MVE
MVE_VSTRWU32 and MVE_VLDRWU32 functions. They behave the same as many
other loads/stores, expecting a FI in Op1 and zero offset in Op2. At the
same time this alters VLDR_P0_off and VSTR_P0_off to use the same code
too, as they too should be returning VPR in Op0, take a FI in Op1 and
zero offset in Op2.
Differential Revision: https://reviews.llvm.org/D106797
The register class required for some MVE loads/stores is more
constrained than the register we use when creating postinc. Make sure we
constrain the register class to keep the code correct.
I have added a new FastMathFlags parameter to getArithmeticReductionCost
to indicate what type of reduction we are performing:
1. Tree-wise. This is the typical fast-math reduction that involves
continually splitting a vector up into halves and adding each
half together until we get a scalar result. This is the default
behaviour for integers, whereas for floating point we only do this
if reassociation is allowed.
2. Ordered. This now allows us to estimate the cost of performing
a strict vector reduction by treating it as a series of scalar
operations in lane order. This is the case when FP reassociation
is not permitted. For scalable vectors this is more difficult
because at compile time we do not know how many lanes there are,
and so we use the worst case maximum vscale value.
I have also fixed getTypeBasedIntrinsicInstrCost to pass in the
FastMathFlags, which meant fixing up some X86 tests where we always
assumed the vector.reduce.fadd/mul intrinsics were 'fast'.
New tests have been added here:
Analysis/CostModel/AArch64/reduce-fadd.ll
Analysis/CostModel/AArch64/sve-intrinsics.ll
Transforms/LoopVectorize/AArch64/strict-fadd-cost.ll
Transforms/LoopVectorize/AArch64/sve-strict-fadd-cost.ll
Differential Revision: https://reviews.llvm.org/D105432
In mandatory tail calling conventions we might have to deallocate stack
space used by our arguments before return. This happens after popping
CSRs, so the pop cannot be turned into the return itself in this case.
The else branch here was already a nop, so removing it as a tidy-up.
This removes the promotion of NEON AND, OR and XOR nodes to v2i32/v4i32,
treating them the same as the AArch64 and MVE backends where we just add
the relevant patterns for each legal type. This prevents a lot of
bitcasts from being added to the DAG, which have the potential to make
optimizations more difficult. It does mean adding extra patterns, and
some codegen can change due to the types now being legal, not promoted.
Differential Revision: https://reviews.llvm.org/D105588
This relaxes the VMLAV and VADDV reduction recognition code to handle
smaller than legal types, extending them as needed. That was already
handled for some reductions, this extends it to more types in a more
generic way. If a smaller than legal value is found it is extended to
the legal type as needed.
Differential Revision: https://reviews.llvm.org/D106051
Oliver Stannard