fixes https://github.com/llvm/llvm-project/issues/98389
As the issue describes, promoting `llvm.fma.f16` to `llvm.fma.f32` does
not work, because there is not enough precision to handle the repeated
rounding. `f64` does have sufficient space. So this PR explicitly
promotes the 16-bit fma to a 64-bit fma.
I could not find examples of a libcall being used for fma, but that's
something that could be looked in separately to work around code size
issues.
This continues the replacement of TargetLibraryInfo uses in codegen
with RuntimeLibcallsInfo started in
821d2825a4f782da3da3c03b8a002802bff4b95c.
The series there handled all of the multiple result calls. This
extends for the other handled case, which happened to be frem.
For some reason the Libcall for these are prefixed with "REM_", for
the instruction "frem", which maps to the libcall "fmod".
We had a set of utilities which was only used for some set of
floating point libcalls. Add more, most of which are for integer
operations.
Ideally we would generate these functions from tablegen.
Previously libcall lowering decisions were made directly
in the TargetLowering constructor. Pull these into the subtarget
to facilitate turning LibcallLoweringInfo into a separate analysis
in the future.
Query RuntimeLibcalls for the support and the name. The check
that the implementation is exactly __guard_local instead of
unsupported feels a bit strange.
Currently LibcallLoweringInfo is defined inside of TargetLowering,
which is owned by the subtarget. Pass in the subtarget so we can
construct LibcallLoweringInfo with the subtarget. This is a temporary
step that should be revertable in the future, after LibcallLoweringInfo
is moved out of TargetLowering.
After the base branch was moved to main, this somehow ended up
adding a second definition of RTLCI, instead of modifying the
existing one.
Also fix other build error with gcc bots.
This fixes the -fveclib flag getting lost on its way to the backend.
Previously this was its own cl::opt with a random boolean. Move the
flag handling into CommandFlags with other backend ABI-ish options,
and have clang directly set it, rather than forcing it to go through
command line parsing.
Prior to de68181d7f, codegen used TargetLibraryInfo to find the vector
function. Clang has special handling for TargetLibraryInfo, where it
would
directly construct one with the vector library in the pass pipeline.
RuntimeLibcallsInfo currently is not used as an analysis in codegen, and
needs to know the vector library when constructed.
RuntimeLibraryAnalysis could follow the same trick that
TargetLibraryInfo is using in the future, but a lot more boilerplate changes
are needed to thread that analysis through codegen. Ideally this would come
from an IR module flag, and nothing would be in TargetOptions. For now, it's
better for all of these sorts of controls to be consistent.
Add libcall entries for sleef and armpl sincospi implementations.
This is the start of adding the vector library functions; eventually
they should all be tracked here.
I'm starting with this case because this is a prerequisite to fix
reporting sincospi calls which do not exist on any common targets
without
regressing vector codegen when these libraries are available.
Introduce a new class for the TargetLowering usage. This tracks the
subtarget specific lowering decisions for which libcall to use.
RuntimeLibcallsInfo is a module level property, which may have multiple
implementations of a particular libcall available. This attempts to be
a minimum boilerplate patch to introduce the new concept.
In the future we should have a tablegen way of selecting which
implementations should be used for a subtarget. Currently we
do have some conflicting implementations added, it just happens
to work out that the default cases to prefer is alphabetically
first (plus some of these still are using manual overrides
in TargetLowering constructors).
Currently it is considered suitable to lower to a bit test for a set of
switch case clusters when the the number of unique destinations
(`NumDests`) and the number of total comparisons (`NumCmps`) satisfy:
`(NumDests == 1 && NumCmps >= 3) || (NumDests == 2 && NumCmps >= 5) ||
(NumDests == 3 && NumCmps >= 6)`
However it is found for some cases on powerpc, for example, when
NumDests is 3, and the number of comparisons for each destination is all
2, it's not profitable to lower the switch to bit test. This is to add
an option to set the minimum of largest number of comparisons to use bit
test for switch lowering.
---------
Co-authored-by: Shimin Cui <scui@xlperflep9.rtp.raleigh.ibm.com>
Reland #161355, after fixing up the cross-projects-tests for the wasm
simd intrinsics.
Original commit message:
Lower v4f32 and v2f64 fmuladd calls to relaxed_madd instructions.
If we have FP16, then lower v8f16 fmuladds to FMA.
I've introduced an ISD node for fmuladd to maintain the rounding
ambiguity through legalization / combine / isel.
Lower v4f32 and v2f64 fmuladd calls to relaxed_madd instructions.
If we have FP16, then lower v8f16 fmuladds to FMA.
I've introduced an ISD node for fmuladd to maintain the rounding
ambiguity through legalization / combine / isel.
As noted in #153256, TableGen is generating reserved names for
RuntimeLibcalls, which resulted in a build failure for Arm64EC since
`vcruntime.h` defines `__security_check_cookie` as a macro.
To avoid using reserved names, all impl names will now be prefixed with
`Impl_`.
`NumLibcallImpls` was lifted out as a `constexpr size_t` instead of
being an enum field.
While I was churning the dependent code, I also removed the TODO to move
the impl enum into its own namespace and use an `enum class`: I
experimented with using an `enum class` and adding a namespace, but we
decided it was too verbose so it was dropped.
It can be unsafe to load a vector from an address and write a vector to
an address if those two addresses have overlapping lanes within a
vectorised loop iteration.
This PR adds intrinsics designed to create a mask with lanes disabled if
they overlap between the two pointer arguments, so that only safe lanes
are loaded, operated on and stored. The `loop.dependence.war.mask`
intrinsic represents cases where the store occurs after the load, and
the opposite for `loop.dependence.raw.mask`. The distinction between
write-after-read and read-after-write is important, since the ordering
of the read and write operations affects if the chain of those
instructions can be done safely.
Along with the two pointer parameters, the intrinsics also take an
immediate that represents the size in bytes of the vector element types.
This will be used by #100579.
Add entries for_stack_chk_guard, __ssp_canary_word, __security_cookie,
and __guard_local. As far as I can tell these are all just different
names for the same shaped functionality on different systems.
These aren't really functions, but special global variable names. They
should probably be treated the same way; all the same contexts that
need to know about emittable function names also need to know about
this. This avoids a special case check in IRSymtab.
This isn't a complete change, there's a lot more cleanup which
should be done. The stack protector configuration system is a
complete mess. There are multiple overlapping controls, used in
3 different places. Some of the target control implementations overlap
with conditions used in the emission points, and some use correlated
but not identical conditions in different contexts.
i.e. useLoadStackGuardNode, getIRStackGuard, getSSPStackGuardCheck and
insertSSPDeclarations are all used in inconsistent ways so I don't know
if I've tracked the intention of the system correctly.
The PowerPC test change is a bug fix on linux. Previously the manual
conditions were based around !isOSOpenBSD, which is not the condition
where __stack_chk_guard are used. Now getSDagStackGuard returns the
proper global reference, resulting in LOAD_STACK_GUARD getting a
MachineMemOperand which allows scheduling.
https://github.com/llvm/llvm-project/pull/152709 exposed the original IR
argument type to the CC lowering logic. However, in SDAG, this used the
raw type, prior to aggregate splitting. This PR changes it to use the
non-aggregate type instead. (This matches what happened in the
GlobalISel case already.)
I've also added some more detailed documentation on the
InputArg/OutputArg fields, to explain how they differ. In most cases
ArgVT is going to be the EVT of OrigTy, so they encode very similar
information (OrigTy just preserves some additional information lost in
EVTs, like pointer types). One case where they do differ is in
post-legalization lowering of libcalls, where ArgVT is going to be a
legalized type, while OrigTy is going to be the original non-legalized
type.
It is common to have ABI requirements for illegal types: For example,
two i64 argument parts that originally came from an fp128 argument may
have a different call ABI than ones that came from a i128 argument.
The current calling convention lowering does not provide access to this
information, so backends come up with various hacks to support it (like
additional pre-analysis cached in CCState, or bypassing the default
logic entirely).
This PR adds the original IR type to InputArg/OutputArg and passes it
down to CCAssignFn. It is not actually used anywhere yet, this just does
the mechanical changes to thread through the new argument.
This introduces a new `ptrtoaddr` instruction which is similar to
`ptrtoint` but has two differences:
1) Unlike `ptrtoint`, `ptrtoaddr` does not capture provenance
2) `ptrtoaddr` only extracts (and then extends/truncates) the low
index-width bits of the pointer
For most architectures, difference 2) does not matter since index (address)
width and pointer representation width are the same, but this does make a
difference for architectures that have pointers that aren't just plain
integer addresses such as AMDGPU fat pointers or CHERI capabilities.
This commit introduces textual and bitcode IR support as well as basic code
generation, but optimization passes do not handle the new instruction yet
so it may result in worse code than using ptrtoint. Follow-up changes will
update capture tracking, etc. for the new instruction.
RFC: https://discourse.llvm.org/t/clarifiying-the-semantics-of-ptrtoint/83987/54
Reviewed By: nikic
Pull Request: https://github.com/llvm/llvm-project/pull/139357
The information whether a specific argument is vararg or fixed is
currently stored separately from all the other argument information in
ArgFlags. This means that it is not accessible from CCAssign, and
backends have developed all kinds of workarounds for how they can access
it after all.
Move this information to ArgFlags to make it directly available in all
relevant places.
I've opted to invert this and store it as IsVarArg, as I think that both
makes the meaning more obvious and provides for a better default (which
is IsVarArg=false).
Compare sinking is selectable based on the result of
hasMultipleConditionRegisters. This function is too coarse grained by
not taking into account the differences between scalar and vector
compares. This PR extends the interface to take an EVT to allow finer
control.
The new interface is used by AArch64 to disable sinking of scalable
vector compares, but with isProfitableToSinkOperands updated to maintain
the cases that are specifically tested.
Add a new combine to replace
```
(store ch (vselect cond truevec (load ch ptr offset)) ptr offset)
```
to
```
(mstore ch truevec ptr offset cond)
```
This saves a blend operation on targets that support conditional stores.
Cygwin and MinGW share the auto import behavior that could result in
__stack_check_guard being non-dso-local. Allow windres to assume a
Cygwin target as well as a MinGW one, so defines like _WIN32 would not
be present on Cygwin.
These float operations were expanded for scalar f32/f64/f128, but not
for f16 and more problematically, not for vectors. A small subset of
them was separately set to expand for vectors.
Change these to always expand by default, and adjust targets to mark
these as legal where necessary instead.
This is a much safer default, and avoids unnecessary legalization
failures because a target failed to manually mark them as expand.
Fixes https://github.com/llvm/llvm-project/issues/110753.
Fixes https://github.com/llvm/llvm-project/issues/121390.
Previously we had a table of entries for every Libcall for
the comparison to use against an integer 0 if it was a soft
float compare function. This was only relevant to a handful of
opcodes, so it was wasteful. Now that we can distinguish the
abstract libcall for the compare with the concrete implementation,
we can just directly hardcode the comparison against the libcall
impl without this configuration system.
This PR takes the work previously done by @pawan-nirpal-031 on X86 in
#106370, and makes it available in common code. This should enable all
targets to use `__builtin_canonicalize` for all `f(16|32|64|128)` data
types.
Canonicalization is implemented here as multiplication by `1.0`, as
suggested in [the
docs](https://llvm.org/docs/LangRef.html#llvm-canonicalize-intrinsic).
We need the full set of ABI options to accurately compute
the full set of libcalls. This partially resolves missing
information required to compute the set of ARM calls.
This fixes an inconsistency in i64 vector handling between RV32 and
RV64. Even if i64 isn't legal as a scalar, we should still be able
to split a large i64 vector to get down to a legal vector type. We only
need to give up if we need to split a vscale x 1 vector.
After pointer element types were removed this function can only return
a GlobalVariable, so reflect that in the type and comments and clean
up callers.
Reviewers: nikic
Reviewed By: nikic
Pull Request: https://github.com/llvm/llvm-project/pull/141323
Add lowering in tablegen for PARTIAL_REDUCE_U/SMLA ISD nodes. Only
happens when the combine has been performed on the ISD node. Also adds
in check to only do the DAG combine when the node can then eventually be
lowered, so changes neon tests too.
---------
Co-authored-by: James Chesterman <james.chesterman@arm.com>
I noticed these destructors taking time with -ftime-trace and moved some
of them for minor build efficiency improvements.
The main impact of moving destructors out of line is that it avoids
requiring container fields containing other types from being complete,
i.e. one can have uptr<T> or vector<T> as a field with an incomplete
type T, and that means we can reduce transitive includes, as with
LegalizerInfo.h.
Move expensive getDebugOperandsForReg template out-of-line. The
std::function instantiation shows up in time trace even if you don't use
the function.
TargetLoweringBase::getIRStackGuard refers to a platform-specific guard
variable. Before this change, TargetLoweringBase::getSDagStackGuard only
referred to a different variable.
This means that SelectionDAGBuilder's getLoadStackGuard does not get
memory operands. However, AArch64InstrInfo::expandPostRAPseudo assumes
that the passed MachineInstr has nonzero memoperands, causing a
segfault.
We have two possible options here: either disabling the LOAD_STACK_GUARD
node entirely in AArch64TargetLowering::useLoadStackGuardNode or just
making the platform-specific values match across TargetLoweringBase.
Here, we try the latter.
Add signed and unsigned PARTIAL_REDUCE_MLA ISD nodes. Add command line
argument (aarch64-enable-partial-reduce-nodes) that indicates whether the
intrinsic experimental_vector_partial_ reduce_add will be transformed
into the new ISD node. Lowering with the new ISD nodes will, for now,
always be done as an expand.
