Fixed stack objects are preallocated and defined to be allocated before
any of the regular stack objects. These are normally used to model stack
arguments.
The AAPCS does not support passing SVE registers on the stack by value
(only by reference). The current layout also doesn't place them before
all stack objects, but rather before all SVE objects. Removing this
simplifies the code that emits the allocation/deallocation
around callee-saved registers (D84042).
This patch also removes all uses of fixedStack from from
framelayout-sve.mir, where this was used purely for testing purposes.
Reviewers: paulwalker-arm, efriedma, rengolin
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D84538
I have introduced a new TargetFrameLowering query function:
isStackIdSafeForLocalArea
that queries whether or not it is safe for objects of a given stack
id to be bundled into the local area. The default behaviour is to
always bundle regardless of the stack id, however for AArch64 this is
overriden so that it's only safe for fixed-size stack objects.
There is future work here to extend this algorithm for multiple local
areas so that SVE stack objects can be bundled together and accessed
from their own virtual base-pointer.
Differential Revision: https://reviews.llvm.org/D83859
Store Addr and Store Addr+8 are clusterable pair. They have memory(ctrl) dependency on different loads.
Current implementation will put these two stores into different group and miss to cluster them.
Reviewed By: evandro
Differential Revision: https://reviews.llvm.org/D84139
Very minor code size improvements (hits 8 times in Bullet at -O3), but still
something.
Also very minor NFC change to make sure we only search for a 0 constant when
selecting a store. Before, we'd do this for loads as well.
Differential Revision: https://reviews.llvm.org/D84573
We weren't performing this optimization on 16 and 32 bit stores. SDAG happily
does this though.
e.g. https://godbolt.org/z/cWocKr
This saves about 0.2% in code size on CTMark at -O3.
Differential Revision: https://reviews.llvm.org/D84568
dacf8d3 added support for most fcmp operations, but there are some extra
variations I hadn't considered: SelectionDAG supports float comparisons
that are neither ordered nor unordered. Add support for the missing
operations.
Differential Revision: https://reviews.llvm.org/D84460
It's sort of tricky to hit this in practice, but not impossible. I have
a synthetic C testcase if anyone is interested.
The implementation is identical to the equivalent NEON register copies.
Differential Revision: https://reviews.llvm.org/D84373
Summary: We do this already for output operands, but missed it for (non-tied) input operands.
Reviewers: arsenm, Petar.Avramovic
Reviewed By: arsenm
Subscribers: jvesely, wdng, nhaehnle, rovka, hiraditya, llvm-commits, kerbowa
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83763
This patch addresses two issues:
* Forces the availability of the base-pointer (x19) when the frame has
both scalable vectors and variable-length arrays. Otherwise it will
be expensive to access non-SVE locals.
* In presence of SVE stack objects, it will allocate the emergency
scavenging slot close to the SP, so that they can be accessed from
the SP or BP if available. If accessed from the frame-pointer, it will
otherwise need an extra register to access the scavenging slot because
of mixed scalable/non-scalable addressing modes.
Reviewers: efriedma, ostannard, cameron.mcinally, rengolin, david-arm
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D70174
This was happening because the BLR didn't have a use of the X0 arg register,
which would end up being re-used in high reg pressure situations.
The change also avoids hard coding the use of X0 for the sequence except to
copy the value for the call. ld64 should still be able to optimize it.
rdar://65438258
There are a few questionable things about this intrinsic and existing
DAG implementation. For some reason the intrinsic hardcodes the second
operand to be scalar-only i32, and SelectionDAG builder makes a
legalization decision based on whether the operand is constant.
The default calling convention needs to save/restore the SVE callee
saves according to the SVE PCS when the function takes or returns
scalable types, even when the `aarch64_sve_vector_pcs` CC is not
specified for the function.
Reviewers: efriedma, paulwalker-arm, david-arm, rengolin
Reviewed By: paulwalker-arm
Differential Revision: https://reviews.llvm.org/D84041
Summary:
Teach LLVM to recognize the above pattern, where the operands are
either signed or unsigned types.
Subscribers: kristof.beyls, hiraditya, danielkiss, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83777
This isn't a natively supported operation, so convert it to a
mask+compare.
In addition to the operation itself, fix up some surrounding stuff to
make the testcase work: we need concat_vectors on i1 vectors, we need
legalization of i1 vector truncates, and we need to fix up all the
relevant uses of getVectorNumElements().
Differential Revision: https://reviews.llvm.org/D83811
Its effect could be achieved by
`-stop-after`,`-print-after`,`-print-after-all`. But a few tests need to
print MIR after ISel which could not be done with
`-print-after`/`-stop-after` since isel pass does not have commandline name.
That's the reason `--print-machineinstrs` is downgraded to
`--print-after-isel` in this patch. `--print-after-isel` could be
removed after we switch to new pass manager since isel pass would have a
commandline text name to use `print-after` or equivalent switches.
The motivation of this patch is to reduce tests dependency on
would-be-deprecated feature.
Reviewed By: arsenm, dsanders
Differential Revision: https://reviews.llvm.org/D83275
It's useful for a debugger to be able to distinguish an @llvm.debugtrap
from a (noreturn) @llvm.trap, so this extends the existing Windows
behaviour to other platforms.
tryLatency compares two sched candidates. For the top zone it prefers
the one with lesser depth, but only if that depth is greater than the
total latency of the instructions we've already scheduled -- otherwise
its latency would be hidden and there would be no stall.
Unfortunately it only tests the depth of one of the candidates. This can
lead to situations where the TopDepthReduce heuristic does not kick in,
but a lower priority heuristic chooses the other candidate, whose depth
*is* greater than the already scheduled latency, which causes a stall.
The fix is to apply the heuristic if the depth of *either* candidate is
greater than the already scheduled latency.
All this also applies to the BotHeightReduce heuristic in the bottom
zone.
Differential Revision: https://reviews.llvm.org/D72392
Lower the operations to predicated variants. This is prep work
required for fixed length code generation but also fixes a bug
whereby these operations fail selection when "unpacked" vector
types (e.g. MVT::nxv2f32) are used.
This patch also adds the missing "unpacked" patterns for FMA.
Differential Revision: https://reviews.llvm.org/D83765
Summary:
This patch modifies IncrementMemoryAddress to use a vscale
when calculating the new address if the data type is scalable.
Also adds tablegen patterns which match an extract_subvector
of a legal predicate type with zip1/zip2 instructions
Reviewers: sdesmalen, efriedma, david-arm
Reviewed By: efriedma, david-arm
Subscribers: tschuett, hiraditya, psnobl, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D83137
The existing code already considered this case. Unfortunately a typo in
the condition prevents it from triggering. Also the existing code, had
it run, forgot to do the folding.
This fixes PR42876.
Differential Revision: https://reviews.llvm.org/D65802
ComputeNumSignBits and computeKnownBits both trigger "Scalable flag
may be dropped" warnings when a fixed length vector is extracted
from a scalable vector. This patch assumes nothing about the
demanded elements thus matching the behaviour when extracting a
scalable vector from a scalable vector.
Differential Revision: https://reviews.llvm.org/D83642
The code already supports addressing a fixed-size stack object from
the frame-pointer, by first subtracting sizeof(SVE area) from FP.
Reviewers: efriedma, cameron.mcinally, david-arm, rengolin
Reviewed By: david-arm
Differential Revision: https://reviews.llvm.org/D83125
I have added a new file:
llvm/test/CodeGen/AArch64/README
that describes what to do in the event one of the SVE codegen tests
fails the warnings check. In addition, I've added comments to all
the relevant SVE tests pointing users at the README file.
Differential Revision: https://reviews.llvm.org/D83467
In DAGCombiner::TransformFPLoadStorePair we were dropping the scalable
property of TypeSize when trying to create an integer type of equivalent
size. In fact, this optimisation makes no sense for scalable types
since we don't know the size at compile time. I have changed the code
to bail out when encountering scalable type sizes.
I've added a test to
llvm/test/CodeGen/AArch64/sve-fp.ll
that exercises this code path. The test already emits an error if it
encounters warnings due to implicit TypeSize->uint64_t conversions.
Differential Revision: https://reviews.llvm.org/D83572
This carves out an exception for a pair of consecutive loads that are
reversed from the consecutive order of a pair of stores. All of the
existing profitability/legality checks for the memops remain between
the 2 altered hunks of code.
This should give us the same x86 base-case asm that gcc gets in
PR41098 and PR44895:
http://bugs.llvm.org/PR41098http://bugs.llvm.org/PR44895
I think we are missing a potential subsequent conversion to use "movbe"
if the target supports that. That might be similar to what AArch64
would use to get "rev16".
Differential Revision: https://reviews.llvm.org/D83567
This carves out an exception for a pair of consecutive loads that are
reversed from the consecutive order of a pair of stores. All of the
existing profitability/legality checks for the memops remain between
the 2 altered hunks of code.
This should give us the same x86 base-case asm that gcc gets in
PR41098 and PR44895:i
http://bugs.llvm.org/PR41098http://bugs.llvm.org/PR44895
I think we are missing a potential subsequent conversion to use "movbe"
if the target supports that. That might be similar to what AArch64
would use to get "rev16".
Differential Revision:
Check that input size matches size of destination reg class.
Attempt to extend input size when needed.
Differential Revision: https://reviews.llvm.org/D83384
fadd (fma A, B, (fmul C, D)), E --> fma A, B, (fma C, D, E)
This is only allowed when "reassoc" is present on the fadd.
As discussed in D80801, this transform goes beyond
what is allowed by "contract" FMF (-ffp-contract=fast).
That is because we are fusing the trailing add of 'E' with a
multiply, but without "reassoc", the code mandates that the
products A*B and C*D are added together before adding in 'E'.
I've added this example to the LangRef to try to clarify the
meaning of "contract". If that seems reasonable, we should
probably do something similar for the clang docs because
there does not appear to be any formal spec for the behavior
of -ffp-contract=fast.
Differential Revision: https://reviews.llvm.org/D82499
This patch upstreams support for the Arm-v8 Cortex-A78 and Cortex-X1
processors for AArch64 and ARM.
In detail:
- Adding cortex-a78 and cortex-x1 as cpu options for aarch64 and arm targets in clang
- Adding Cortex-A78 and Cortex-X1 CPU names and ProcessorModels in llvm
details of the CPU can be found here:
https://www.arm.com/products/cortex-xhttps://www.arm.com/products/silicon-ip-cpu/cortex-a/cortex-a78
The following people contributed to this patch:
- Luke Geeson
- Mikhail Maltsev
Reviewers: t.p.northover, dmgreen
Reviewed By: dmgreen
Subscribers: dmgreen, kristof.beyls, hiraditya, danielkiss, cfe-commits,
llvm-commits, miyuki
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D83206
