This patch adds support for Arm's Cortex-M85 CPU. The Cortex-M85 CPU is
an Arm v8.1m Mainline CPU, with optional support for MVE and PACBTI,
both of which are enabled by default.
Parts have been coauthored by by Mark Murray, Alexandros Lamprineas and
David Green.
Differential Revision: https://reviews.llvm.org/D128415
Currently the a AAPCS compliant frame record is not always created for
functions when it should. Although a consistent frame record might not
be required in some cases, there are still scenarios where applications
may want to make use of the call hierarchy made available trough it.
In order to enable the use of AAPCS compliant frame records whilst keep
backwards compatibility, this patch introduces a new command-line option
(`-mframe-chain=[none|aapcs|aapcs+leaf]`) for Aarch32 and Thumb backends.
The option allows users to explicitly select when to use it, and is also
useful to ensure the extra overhead introduced by the frame records is
only introduced when necessary, in particular for Thumb targets.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D125094
Deciding to load an arbitrary global based on whether the entire module is
being built for long calls is pretty clearly spurious, and in fact the existing
indirect logic is sufficient.
Remove the known limitation of the library function call folders to only
work with top-level arrays of characters (as per the TODO comment in
the code) and allows them to also fold calls involving subobjects of
constant aggregates such as member arrays.
Similar to the existing (shl (srl x, c1), c2) fold
Part of the work to fix the regressions in D77804
Differential Revision: https://reviews.llvm.org/D125836
The VT we want to shrink to may not be legal especially after type
legalization.
Fixes PR56110.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D128135
This reverts commit 7625e01d661644a560884057755d48a0da8b77b4 and
dependent cbcce82ef6b512d97e92a319a75a03e997c844e1.
Commit 7625e01d661644a560884057755d48a0da8b77b4 causes some new codegen test
failures under asan, e.g., CodeGen/ARM/execute-only.ll:
https://lab.llvm.org/buildbot/#/builders/5/builds/24659/steps/15/logs/stdio.
Currently the a AAPCS compliant frame record is not always created for
functions when it should. Although a consistent frame record might not
be required in some cases, there are still scenarios where applications
may want to make use of the call hierarchy made available trough it.
In order to enable the use of AAPCS compliant frame records whilst keep
backwards compatibility, this patch introduces a new command-line option
(`-mframe-chain=[none|aapcs|aapcs+leaf]`) for Aarch32 and Thumb backends.
The option allows users to explicitly select when to use it, and is also
useful to ensure the extra overhead introduced by the frame records is
only introduced when necessary, in particular for Thumb targets.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D125094
Another issue unearthed by D127115
We take a long time to canonicalize an insert_vector_elt chain before being able to convert it into a build_vector - even if they are already in ascending insertion order, we fold the nodes one at a time into the build_vector 'seed', leaving plenty of time for other folds to alter it (in particular recognising when they come from extract_vector_elt resulting in a shuffle_vector that is much harder to fold with).
D127115 makes this particularly difficult as we're almost guaranteed to have the lost the sequence before all possible insertions have been folded.
This patch proposes to begin at the last insertion and attempt to collect all the (oneuse) insertions right away and create the build_vector before its too late.
Differential Revision: https://reviews.llvm.org/D127595
Currently the a AAPCS compliant frame record is not always created for
functions when it should. Although a consistent frame record might not
be required in some cases, there are still scenarios where applications
may want to make use of the call hierarchy made available trough it.
In order to enable the use of AAPCS compliant frame records whilst keep
backwards compatibility, this patch introduces a new command-line option
(`-mframe-chain=[none|aapcs|aapcs+leaf]`) for Aarch32 and Thumb backends.
The option allows users to explicitly select when to use it, and is also
useful to ensure the extra overhead introduced by the frame records is
only introduced when necessary, in particular for Thumb targets.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D125094
We intentionally disable Thumb2SizeReduction for SEH
prologues/epilogues, to avoid needing to guess what will happen with
the instructions in a potential future pass in frame lowering.
But for this specific case, where we know we can express the
intent with a narrow instruction, change to that instruction form
directly in frame lowering.
Differential Revision: https://reviews.llvm.org/D126949
We intentionally disable Thumb2SizeReduction for SEH
prologues/epilogues, to avoid needing to guess what will happen with
the instructions in a potential future pass in frame lowering.
But for this specific case, where we know we can express the
intent with a narrow instruction, change to that instruction form
directly in frame lowering.
Differential Revision: https://reviews.llvm.org/D126948
The test looked for the wrong string, but it happened to match as
it was a substring of the actual output.
This fixes a typo from d8e67c1cccd8fcb62230166caea744592288da17.
For functions that require restoring SP from FP (e.g. that need to
align the stack, or that have variable sized allocations), the prologue
and epilogue previously used to look like this:
push {r4-r5, r11, lr}
add r11, sp, #8
...
sub r4, r11, #8
mov sp, r4
pop {r4-r5, r11, pc}
This is problematic, because this unwinding operation (restoring sp
from r11 - offset) can't be expressed with the SEH unwind opcodes
(probably because this unwind procedure doesn't map exactly to
individual instructions; note the detour via r4 in the epilogue too).
To make unwinding work, the GPR push is split into two; the first one
pushing all other registers, and the second one pushing r11+lr, so that
r11 can be set pointing at this spot on the stack:
push {r4-r5}
push {r11, lr}
mov r11, sp
...
mov sp, r11
pop {r11, lr}
pop {r4-r5}
bx lr
For the same setup, MSVC generates code that uses two registers;
r11 still pointing at the {r11,lr} pair, but a separate register
used for restoring the stack at the end:
push {r4-r5, r7, r11, lr}
add r11, sp, #12
mov r7, sp
...
mov sp, r7
pop {r4-r5, r7, r11, pc}
For cases with clobbered float/vector registers, they are pushed
after the GPRs, before the {r11,lr} pair.
Differential Revision: https://reviews.llvm.org/D125649
Skip inserting regular CFI instructions if using WinCFI.
This is based a fair amount on the corresponding ARM64 implementation,
but instead of trying to insert the SEH opcodes one by one where
we generate other prolog/epilog instructions, we try to walk over the
whole prolog/epilog range and insert them. This is done because in
many cases, the exact number of instructions inserted is abstracted
away deeper.
For some cases, we manually insert specific SEH opcodes directly where
instructions are generated, where the automatic mapping of instructions
to SEH opcodes doesn't hold up (e.g. for __chkstk stack probes).
Skip Thumb2SizeReduction for SEH prologs/epilogs, and force
tail calls to wide instructions (just like on MachO), to make sure
that the unwind info actually matches the width of the final
instructions, without heuristics about what later passes will do.
Mark SEH instructions as scheduling boundaries, to make sure that they
aren't reordered away from the instruction they describe by
PostRAScheduler.
Mark the SEH instructions with the NoMerge flag, to avoid doing
tail merging of functions that have multiple epilogs that all end
with the same sequence of "b <other>; .seh_nop_w, .seh_endepilogue".
Differential Revision: https://reviews.llvm.org/D125648
This enabled opaque pointers by default in LLVM. The effect of this
is twofold:
* If IR that contains *neither* explicit ptr nor %T* types is passed
to tools, we will now use opaque pointer mode, unless
-opaque-pointers=0 has been explicitly passed.
* Users of LLVM as a library will now default to opaque pointers.
It is possible to opt-out by calling setOpaquePointers(false) on
LLVMContext.
A cmake option to toggle this default will not be provided. Frontends
or other tools that want to (temporarily) keep using typed pointers
should disable opaque pointers via LLVMContext.
Differential Revision: https://reviews.llvm.org/D126689
Adds MVT::v128i2, MVT::v64i4, and implied MVT::i2, MVT::i4.
Keeps MVT::i2, MVT::i4 lowering actions as expand, which should be
removed once targets set this explicitly.
Adjusts 11 lit tests to reflect slightly different behavior during
DAG combine.
Differential Revision: https://reviews.llvm.org/D125247
Adds MVT::v128i2, MVT::v64i4, and implied MVT::i2, MVT::i4.
Keeps MVT::i2, MVT::i4 lowering actions as `expand`, which should be
removed once targets set this explicitly.
Adjusts 11 lit tests to reflect slightly different behavior during
DAG combine.
Differential Revision: https://reviews.llvm.org/D125247
As discussed on D77804, instcombine will have already performed a similar SimplifyMultipleUseDemandedBits call which will break the UXTB16 pattern that was being match in these DAG tests
I've updated the existing tests so that it match the instcombine IR (with a suitable FIXME) and added an equivalent test pattern suggested by @dmgreen
There are a few places where we use report_fatal_error when the input is broken.
Currently, this function always crashes LLVM with an abort signal, which
then triggers the backtrace printing code.
I think this is excessive, as wrong input shouldn't give a link to
LLVM's github issue URL and tell users to file a bug report.
We shouldn't print a stack trace either.
This patch changes report_fatal_error so it uses exit() rather than
abort() when its argument GenCrashDiag=false.
Reviewed by: nikic, MaskRay, RKSimon
Differential Revision: https://reviews.llvm.org/D126550
reapply 62a9b36fcf728b104ea87e6eb84c0be69b779df7 and fix module build
failue:
1: remove MachineCycleInfoWrapperPass in MachinePassRegistry.def
MachineCycleInfoWrapperPass is a anylysis pass, should not be there.
2: move the definition for MachineCycleInfoPrinterPass to cpp file.
Otherwise, there are module conflicit for MachineCycleInfoWrapperPass
in MachinePassRegistry.def and MachineCycleAnalysis.h after
62a9b36fcf728b104ea87e6eb84c0be69b779df7.
MachineCycle can handle irreducible loop. Natural loop
analysis (MachineLoop) can not return correct loop depth if
the loop is irreducible loop. And MachineSink is sensitive
to the loop depth, see MachineSinking::isProfitableToSinkTo().
This patch tries to use MachineCycle so that we can handle
irreducible loop better.
Reviewed By: sameerds, MatzeB
Differential Revision: https://reviews.llvm.org/D123995
The `vcvtb.f16.f32 Sd, Sn` (and vcvtt.f16.f32) instruction convert a f32
into a f16, writing either the top or bottom halves of the register.
That means that half of the input register Sd is used in the output.
This wasn't being modelled in the instructions, leading later analyses
to believe that the registers were dead where they were not, generating
invalid scheduling
Fix that be specifying the input Sda register for the instructions too,
allowing them to be set for cases like vector inserts. Most of the
changes are plumbing through the constraint string, cstr.
Differential Revision: https://reviews.llvm.org/D126118
MachineCycle can handle irreducible loop. Natural loop
analysis (MachineLoop) can not return correct loop depth if
the loop is irreducible loop. And MachineSink is sensitive
to the loop depth, see MachineSinking::isProfitableToSinkTo().
This patch tries to use MachineCycle so that we can handle
irreducible loop better.
Reviewed By: sameerds, MatzeB
Differential Revision: https://reviews.llvm.org/D123995
The TC_RETURN/TCRETURNdi under Arm does not currently add the
register-mask operand when tail folding, which leads to the register
(like LR) not being 'used' by the return. This changes the code to
unconditionally set the register mask on the call, as opposed to
skipping it for tail calls.
I don't believe this will currently alter any codegen, but should glue
things together better post-frame lowering. It matches the AArch64 code
better.
Differential Revision: https://reviews.llvm.org/D125906
This function tries to match (a >> 8) | (a << 8) as (bswap a) >> 16.
If the SRL isn't masked and the high bits aren't demanded, we still
need to ensure that bits 23:16 are zero. After the right shift they
will be in bits 15:8 which is where the important bits from the SHL
end up. It's only a bswap if the OR on bits 15:8 only takes the bits
from the SHL.
Fixes PR55484.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D125641
If we're using shift pairs to mask, then relax the one use limit if the shift amounts are equal - we'll only be generating a single AND node.
AArch64 has a couple of regressions due to this, so I've enforced the existing one use limit inside a AArch64TargetLowering::shouldFoldConstantShiftPairToMask callback.
Part of the work to fix the regressions in D77804
Differential Revision: https://reviews.llvm.org/D125607
This bug is in generic DAG combine and easily reproducible on many
targets.
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D125640
This adds a late Machine Pass to work around a Cortex CPU Erratum
affecting Cortex-A57 and Cortex-A72:
- Cortex-A57 Erratum 1742098
- Cortex-A72 Erratum 1655431
The pass inserts instructions to make the inputs to the fused AES
instruction pairs no longer trigger the erratum. Here the pass errs on
the side of caution, inserting the instructions wherever we cannot prove
that the inputs came from a safe instruction.
The pass is used:
- for Cortex-A57 and Cortex-A72,
- for "generic" cores (which are used when using `-march=`),
- when the user specifies `-mfix-cortex-a57-aes-1742098` or
`mfix-cortex-a72-aes-1655431` in the command-line arguments to clang.
Reviewed By: dmgreen, simon_tatham
Differential Revision: https://reviews.llvm.org/D119720
This prevents an infinite loop from D123801, where code trying to reduce
the total number of bitcasts, but also handling constants, could create
the opposite transform. Prevent the transform in these case to let the
bitcast of a constant transform naturally.
Fixes#55345
This is part of an ongoing effort toward making DAGCombine process the nodes in topological order.
This is able to discover a couple of new optimizations, but also causes a couple of regression. I nevertheless chose to submit this patch for review as to start the discussion with people working on the backend so we can find a good way forward.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D124743
As discussed on D124839, we're almost certainly only ever going to see this from IR directly - which now will create funnel shift intrinsics directly
I've also added a couple of rotl(rotr()) tests to check left/right rotation merging.
Otherwise we have garbage in the upper bits that can affect the
results of the UREM.
Fixes PR55296.
Differential Revision: https://reviews.llvm.org/D125076
If the mask is made up of elements that form a mask in the higher type
we can convert shuffle(bitcast into the bitcast type, simplifying the
instruction sequence. A v4i32 2,3,0,1 for example can be treated as a
1,0 v2i64 shuffle. This helps clean up some of the AArch64 concat load
combines, along with helping simplify a number of other tests.
The PowerPC combine for v16i8 splat vector loads needed some fixes to
keep it working for v16i8 vectors. This improves the handling of v2i64
shuffles to match too, hopefully improving them in general.
Differential Revision: https://reviews.llvm.org/D123801
This adds a big endian run line for the AArch64 TRN tests and
regenerated the check lines, along with adding an extra MVE VMOVN case
and regenerating vector-DAGCombine.ll for easier updating.
When adjusting the function prologue for segmented stacks, only update
the successor edges of the immediate predecessors of the original
prologue.
Differential Revision: https://reviews.llvm.org/D122959
