Add an extra parameter so the backend can take the alignment into
consideration.
Differential Revision: https://reviews.llvm.org/D68400
llvm-svn: 374763
This prevents isel from emitting a TEST instruction that
optimizeCompareInstr will need to remove later.
In some of the modified tests, the SUB gets duplicated due to
the flags being needed in two places and being clobbered in
between. optimizeCompareInstr was able to optimize away the TEST
that was using the result of one of them, but optimizeCompareInstr
doesn't know to turn SUB into CMP after removing the TEST. It
only knows how to turn SUB into CMP if the result was already
dead.
With this change the TEST never exists, so optimizeCompareInstr
doesn't have to remove it. Then it can just turn the SUB into
CMP immediately.
Fixes PR43649.
llvm-svn: 374755
We were already controlling whether the KnownZero elements were being written to the target mask, this extends it to the KnownUndef elements as well so we can prevent the target shuffle mask being manipulated at all.
llvm-svn: 374732
This enables use of the saturating truncate instructions when the
result type is less than 128 bits. It also enables the use of
saturating truncate instructions on KNL when the input is less
than 512 bits. We can do this by widening the input and then
extracting the result.
llvm-svn: 374731
This seems to improve std::midpoint code where we have a min and
a max with the same condition. If we split the setcc we can end
up with two compares if the one of the operands is a constant.
Since we aggressively canonicalize compares with constants.
For non-constants it can interfere with our ability to share
control flow if we need to expand cmovs into control flow.
I'm also not sure I understand this min/max canonicalization code.
The motivating case talks about comparing with 0. But we don't
check for 0 explicitly.
Removes one instruction from the codegen for PR43658.
llvm-svn: 374706
I can't see any notable differences in costs between SSE2 and SSE42 arches for FADD/ADD reduction, so I've lowered the target to just SSE2.
I've also added vXi8 sum reduction costs in line with the PSADBW codegen and discussions on PR42674.
llvm-svn: 374655
Since the input type is larger than 256-bits we'll need to some
concatenating to reassemble the results. The pack instructions
ability to concatenate while packing make this a shorter/faster
sequence.
llvm-svn: 374643
The commit of rL374420 had various formatting issues, including lines
that exceed 80 columns. This patch applies `git clang-format` on the
changes from commit 13bd3ef40d.
It further adjusts a comment to clarify the domain of inputs upon which
a newly added function is meant to operate. The adjustment to the
comment was suggested in a post-commit comment on D68721 and discussed
off-list with @sfertile.
llvm-svn: 374635
In loop-vectorize, interleave count and vector factor depend on target register number. Currently, it does not
estimate different register pressure for different register class separately(especially for scalar type,
float type should not be on the same position with int type), so it's not accurate. Specifically,
it causes too many times interleaving/unrolling, result in too many register spills in loop body and hurting performance.
So we need classify the register classes in IR level, and importantly these are abstract register classes,
and are not the target register class of backend provided in td file. It's used to establish the mapping between
the types of IR values and the number of simultaneous live ranges to which we'd like to limit for some set of those types.
For example, POWER target, register num is special when VSX is enabled. When VSX is enabled, the number of int scalar register is 32(GPR),
float is 64(VSR), but for int and float vector register both are 64(VSR). So there should be 2 kinds of register class when vsx is enabled,
and 3 kinds of register class when VSX is NOT enabled.
It runs on POWER target, it makes big(+~30%) performance improvement in one specific bmk(503.bwaves_r) of spec2017 and no other obvious degressions.
Differential revision: https://reviews.llvm.org/D67148
llvm-svn: 374634
We already did this for VTRUNCUS with a specific combination of
types. This extends this to VTRUNCS and handles any types where
a truncating store is legal.
llvm-svn: 374615
This defaults to zero fi operand, but we do not expose it
anyway. Should we expose it later it needs to be added to
the pseudo.
This enables dpp combining on gfx10.
Differential Revision: https://reviews.llvm.org/D68888
llvm-svn: 374604
Now assembler generates two consecutive `.4byte` directives to store
64-bit `li.d' operand. The first directive stores high 4-byte of the
value. The second directive stores low 4-byte of the value. But on
64-bit system we load this value at once and get wrong result if the
system is little-endian.
This patch fixes the bug. It stores the `li.d' operand as a single
8-byte value.
Differential Revision: https://reviews.llvm.org/D68778
llvm-svn: 374598
If `li.s` or `li.d` loads zero into a FPR, it's not necessary to load
zero into `at` GPR register and then move its value into a floating
point register. We can use as a source register the `zero / $0` one.
Differential Revision: https://reviews.llvm.org/D68777
llvm-svn: 374597
The target does just enough to be able to run llvm-exegesis in latency
mode for at least some opcodes.
Patch by Miloš Stojanović.
Differential Revision: https://reviews.llvm.org/D68649
llvm-svn: 374590
Summary:
The AIX system assembler does not understand .zero, so we should prefer
emitting .space.
Subscribers: nemanjai, hiraditya, kbarton, MaskRay, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68815
llvm-svn: 374564
If a "double" (64-bit) value has zero low 32-bits, it's possible to load
such value into a GP/FP registers as an instruction immediate. But now
assembler loads only high 32-bits of the value.
For example, if a target register is GPR the `li.d $4, 1.0` instruction
converts into the `lui $4, 16368` one. As a result, we get `0x3FF00000`
in the register. While a correct representation of the `1.0` value is
`0x3FF0000000000000`. The patch fixes that.
Differential Revision: https://reviews.llvm.org/D68776
llvm-svn: 374544
The assertion is everzealous and fail tests like:
renamable $x3 = LI8 0
STD renamable $x3, 16, $x1
renamable $x3 = LI8 0
Remove the assertion since killed flag of $x3 is not mandentory.
Differential Revision: https://reviews.llvm.org/D68344
llvm-svn: 374515
If we don't have VLX we won't end up selecting a saturating
truncate for 256-bit or smaller vectors so we should just use
the pack lowering.
llvm-svn: 374487
When handling the packus pattern for i32->i8 we do a two step
process using a packss to i16 followed by a packus to i8. If the
final i8 step is a type with less than 64-bits the packus step
will return SDValue(), but the i32->i16 step might have succeeded.
This leaves the nodes from the middle step dangling.
Guard against this by pre-checking that the number of elements is
at least 8 before doing the middle step.
With that check in place this should mean the only other
case the middle step itself can fail is when SSE2 is disabled. So
add an early SSE2 check then just assert that neither the middle
or final step ever fail.
llvm-svn: 374460
If we've disable zmm registers, the v16i32 will need to be split. This split will propagate through min/max the truncate. This creates two sequences that need to be concatenated back to v16i8. We can instead use packusdw to do part of the clamping, truncating, and concatenating all at once. Then we can use a vpmovuswb to finish off the clamp.
Differential Revision: https://reviews.llvm.org/D68763
llvm-svn: 374431
Add a helper function getMCSymbolForTOCPseudoMO to clean up PPCAsmPrinter
a little bit.
Differential Revision: https://reviews.llvm.org/D68721
llvm-svn: 374420
Previously, patchable extern relocations are introduced to patch
external variables used for multi versioning in
compile once, run everywhere use case. The load instruction
will be converted into a move with an patchable immediate
which can be changed by bpf loader on the host.
The kernel verifier has evolved and is able to load
and propagate constant values, so compiler relocation
becomes unnecessary. This patch removed codes related to this.
Differential Revision: https://reviews.llvm.org/D68760
llvm-svn: 374367
Summary:
This has been superseded by "[AMDGPU]: PHI Elimination hooks added for custom COPY insertion."
This reverts the code changes from commit 53f967f2bd
but keeps the test case.
Reviewers: hliao, arsenm, tpr, dstuttard
Subscribers: kzhuravl, jvesely, wdng, nhaehnle, yaxunl, t-tye, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68769
llvm-svn: 374347
This selects MVE VQADD from the vector llvm.sadd.sat or llvm.uadd.sat
intrinsics.
Differential Revision: https://reviews.llvm.org/D68566
llvm-svn: 374336
EXPENSIVE_CHECKS build was failing on new test.
This is fixed by marking $ra register as undef.
Test now has -verify-machineinstrs to check for operand flags.
llvm-svn: 374320
Currently, the heuristics the if-conversion pass uses for diamond if-conversion
are based on execution time, with no consideration for code size. This adds a
new set of heuristics to be used when optimising for code size.
This is mostly target-independent, because the if-conversion pass can
see the code size of the instructions which it is removing. For thumb,
there are a few passes (insertion of IT instructions, selection of
narrow branches, and selection of CBZ instructions) which are run after
if conversion and affect these heuristics, so I've added target hooks to
better predict the code-size effect of a proposed if-conversion.
Differential revision: https://reviews.llvm.org/D67350
llvm-svn: 374301
SGPR_128 only includes the real allocatable SGPRs, and SReg_128 adds
the additional non-allocatable TTMP registers. There's no point in
allocating SReg_128 vregs. This shrinks the size of the classes
regalloc needs to consider, which is usually good.
llvm-svn: 374284
As background, starting in D66309, I'm working on support unordered atomics analogous to volatile flags on normal LoadSDNode/StoreSDNodes for X86.
As part of that, I spent some time going through usages of LoadSDNode and StoreSDNode looking for cases where we might have missed a volatility check or need an atomic check. I couldn't find any cases that clearly miscompile - i.e. no test cases - but a couple of pieces in code loop suspicious though I can't figure out how to exercise them.
This patch adds defensive checks and asserts in the places my manual audit found. If anyone has any ideas on how to either a) disprove any of the checks, or b) hit the bug they might be fixing, I welcome suggestions.
Differential Revision: https://reviews.llvm.org/D68419
llvm-svn: 374261
In a future patch, this will help cleanup m0 handling.
The register coalescer handles copies from a register that
materializes an immediate, but doesn't handle move immediates
itself. The virtual register uses will often be allocated to the same
register, so there end up being no real copy.
llvm-svn: 374257
This was ignoring the register bank of the input pointer, and
isUniformMMO seems overly aggressive.
This will now conservatively assume a VGPR in cases where the incoming
bank hasn't been determined yet (i.e. is from a loop phi).
llvm-svn: 374255
If original instruction did not have source modifiers they were
not added to the new DPP instruction as well, even if needed.
Differential Revision: https://reviews.llvm.org/D68729
llvm-svn: 374241
Summary:
This is necessary and sufficient to get simple cases of multiple
return working with multivalue enabled. More complex cases will
require block and loop signatures to be generalized to potentially be
type indices as well.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68684
llvm-svn: 374235
Re-apply 9fdfb045ae8b/r365676 with fixes for PPC and Hexagon. This involved
moving defaults from TargetTransformInfoImplBase to MCSubtargetInfo.
Rework the TTI cache and software prefetching APIs to prepare for the
introduction of a general system model. Changes include:
- Marking existing interfaces const and/or override as appropriate
- Adding comments
- Adding BasicTTIImpl interfaces that delegate to a subtarget
implementation
- Moving the default TargetTransformInfoImplBase implementation to a default
MCSubtarget implementation
Only a handful of targets use these interfaces currently: AArch64, Hexagon, PPC
and SystemZ. AArch64 already has a custom subtarget implementation, so its
custom TTI implementation is migrated to use the new facilities in BasicTTIImpl
to invoke its custom subtarget implementation. The custom TTI implementations
continue to exist for the other targets with this change. They are not moved
over to subtarget-based implementations.
The end goal is to have the default subtarget implementation defer to the system
model defined by the target. With this change, the default MCSubtargetInfo
implementation essentially returns the defaults TargetTransformInfoImplBase used
to return. Existing users of TTI defaults will hit the defaults now in
MCSubtargetInfo. Targets that define their own custom TTI implementations won't
use the BasicTTIImpl implementations that route to the subtarget.
Once system models are in place for the targets that use these interfaces, their
custom TTI implementations can be removed.
Differential Revision: https://reviews.llvm.org/D63614
llvm-svn: 374205
Summary:
This clang builtin and corresponding LLVM intrinsic are necessary to
expose the exact semantics of the underlying WebAssembly instruction
to users. LLVM produces a poison value if the dynamic swizzle indices
are greater than the vector size, but the WebAssembly instruction sets
the corresponding output lane to zero. Users who depend on this
behavior can safely use this builtin.
Depends on D68527.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D68531
llvm-svn: 374189
Summary:
Adds the new v8x16.swizzle SIMD instruction as specified at
https://github.com/WebAssembly/simd/blob/master/proposals/simd/SIMD.md#swizzling-using-variable-indices.
In addition to adding swizzles as a candidate lowering in
LowerBUILD_VECTOR, also rewrites and simplifies the lowering to
minimize the number of replace_lanes necessary rather than trying to
minimize code size. This leads to more uses of v128.const instead of
splats, which is expected to increase performance.
The new code will be easier to tune once V8 implements all the vector
construction operations, and it will also be easier to add new
candidate instructions in the future if necessary.
Reviewers: aheejin, dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68527
llvm-svn: 374188
stack
This patch makes sure that if we tag some memory, we untag that memory before
the function returns/throws via any exit, reachable from the tag operation. For
that we place the untag operation either at:
a) the lifetime end call for the alloca, if that call post-dominates the
lifetime start call (where the tag operation is placed), or it (the
lifetime end call) dominates all reachable exits, otherwise
b) at the reachable exits
Differential Revision: https://reviews.llvm.org/D68469
llvm-svn: 374182
The `expandLoadImmReal` handles four different and almost non-overlapping
cases: loading a "single" float immediate into a GPR, loading a "single"
float immediate into a FPR, and the same couple for a "double" float
immediate.
It's better to move each `else if` branch into separate methods.
llvm-svn: 374164
There were 2 problems here. First, these patterns were duplicated to
handle the inverted shift operands instead of using the commuted
PatFrags.
Second, the point of the zext folding patterns don't apply to the
non-0ing high subtargets. They should be skipped instead of inserting
the extension. The zeroing high code would be emitted when necessary
anyway. This was also emitting unnecessary zexts in cases where the
high bits were undefined.
llvm-svn: 374092
Also Revert "[LoopVectorize] Fix non-debug builds after rL374017"
This reverts commit 9f41deccc0.
This reverts commit 18b6fe07bc.
The patch is breaking PowerPC internal build, checked with author, reverting
on behalf of him for now due to timezone.
llvm-svn: 374091
Summary:
Without offsets on the MachineMemOperands (MMOs),
MachineInstr::mayAlias() will return true for all reads and writes to the
same resource descriptor. This leads to O(N^2) complexity in the MachineScheduler
when analyzing dependencies of buffer loads and stores. It also limits
the SILoadStoreOptimizer from merging more instructions.
This patch reduces the compile time of one pathological compute shader
from 12 seconds to 1 second.
Reviewers: arsenm, nhaehnle
Reviewed By: arsenm
Subscribers: kzhuravl, jvesely, wdng, yaxunl, dstuttard, tpr, t-tye, hiraditya, jfb, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D65097
llvm-svn: 374087
Inhibit generation of unused real dpp instructions on gfx10 just
like it is done on other subtargets. This does not change anything
because these are illegal anyway and not accepted, but it does
reduce the number of instruction definitions generated.
Differential Revision: https://reviews.llvm.org/D68607
llvm-svn: 374083
Summary:
When searching for local expression tree created by stackified
registers, for 'block' placement, we start the search from the previous
instruction of a BB's terminator. But in 'try''s case, we should start
from the previous instruction of a call that can throw, or a EH_LABEL
that precedes the call, because the return values of the call's previous
instructions can be stackified and consumed by the throwing call.
For example,
```
i32.call @foo
call @bar ; may throw
br $label0
```
In this case, if we start the search from the previous instruction of
the terminator (`br` here), we end up stopping at `call @bar` and place
a 'try' between `i32.call @foo` and `call @bar`, because `call @bar`
does not have a return value so it is not a local expression tree of
`br`.
But in this case, unlike when placing 'block's, we should start the
search from `call @bar`, because the return value of `i32.call @foo` is
stackified and used by `call @bar`.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68619
llvm-svn: 374073
During the If-Converter optimization pay attention when copying or
deleting call instructions in order to keep call site information in
valid state.
Reviewers: aprantl, vsk, efriedma
Reviewed By: vsk, efriedma
Differential Revision: https://reviews.llvm.org/D66955
llvm-svn: 374068
When -pg option is present than a call to _mcount is inserted into every
function. However since the proper ABI was not followed then the generated
gmon.out did not give proper results. By inserting needed instructions
before every _mcount we can fix this.
Differential Revision: https://reviews.llvm.org/D68390
llvm-svn: 374055
Tim Northover remarked that the added patterns for fmls fp16
produce wrong code in case the fsub instruction has a
multiplication as its first operand, i.e., all the patterns FMLSv*_OP1:
> define <8 x half> @test_FMLSv8f16_OP1(<8 x half> %a, <8 x half> %b, <8 x half> %c) {
> ; CHECK-LABEL: test_FMLSv8f16_OP1:
> ; CHECK: fmls {{v[0-9]+}}.8h, {{v[0-9]+}}.8h, {{v[0-9]+}}.8h
> entry:
>
> %mul = fmul fast <8 x half> %c, %b
> %sub = fsub fast <8 x half> %mul, %a
> ret <8 x half> %sub
> }
>
> This doesn't look right to me. The exact instruction produced is "fmls
> v0.8h, v2.8h, v1.8h", which I think calculates "v0 - v2*v1", but the
> IR is calculating "v2*v1-v0". The equivalent <4 x float> code also
> doesn't emit an fmls.
This patch generates an fmla and negates the value of the operand2 of the fsub.
Inspecting the pattern match, I found that there was another mistake in the
opcode to be selected: matching FMULv4*16 should generate FMLSv4*16
and not FMLSv2*32.
Tested on aarch64-linux with make check-all.
Differential Revision: https://reviews.llvm.org/D67990
llvm-svn: 374044
* Adds a TypeSize struct to represent the known minimum size of a type
along with a flag to indicate that the runtime size is a integer multiple
of that size
* Converts existing size query functions from Type.h and DataLayout.h to
return a TypeSize result
* Adds convenience methods (including a transparent conversion operator
to uint64_t) so that most existing code 'just works' as if the return
values were still scalars.
* Uses the new size queries along with ElementCount to ensure that all
supported instructions used with scalable vectors can be constructed
in IR.
Reviewers: hfinkel, lattner, rkruppe, greened, rovka, rengolin, sdesmalen
Reviewed By: rovka, sdesmalen
Differential Revision: https://reviews.llvm.org/D53137
llvm-svn: 374042
Support for tracking registers that forward function parameters into the
following function frame. For now we only support cases when parameter
is forwarded through single register.
Reviewers: aprantl, vsk, t.p.northover
Reviewed By: vsk
Differential Revision: https://reviews.llvm.org/D66953
llvm-svn: 374033
Based on the discussion in
http://lists.llvm.org/pipermail/llvm-dev/2019-October/135574.html, the
conclusion was reached that the ARM backend should produce vcmp instead
of vcmpe instructions by default, i.e. not be producing an Invalid
Operation exception when either arguments in a floating point compare
are quiet NaNs.
In the future, after constrained floating point intrinsics for floating
point compare have been introduced, vcmpe instructions probably should
be produced for those intrinsics - depending on the exact semantics
they'll be defined to have.
This patch logically consists of the following parts:
- Revert http://llvm.org/viewvc/llvm-project?rev=294945&view=rev and
http://llvm.org/viewvc/llvm-project?rev=294968&view=rev, which
implemented fine-tuning for when to produce vcmpe (i.e. not do it for
equality comparisons). The complexity introduced by those patches
isn't needed anymore if we just always produce vcmp instead. Maybe
these patches need to be reintroduced again once support is needed to
map potential LLVM-IR constrained floating point compare intrinsics to
the ARM instruction set.
- Simply select vcmp, instead of vcmpe, see simple changes in
lib/Target/ARM/ARMInstrVFP.td
- Adapt lots of tests that tested for vcmpe (instead of vcmp). For all
of these test, the intent of what is tested for isn't related to
whether the vcmp should produce an Invalid Operation exception or not.
Fixes PR43374.
Differential Revision: https://reviews.llvm.org/D68463
llvm-svn: 374025
In loop-vectorize, interleave count and vector factor depend on target register number. Currently, it does not
estimate different register pressure for different register class separately(especially for scalar type,
float type should not be on the same position with int type), so it's not accurate. Specifically,
it causes too many times interleaving/unrolling, result in too many register spills in loop body and hurting performance.
So we need classify the register classes in IR level, and importantly these are abstract register classes,
and are not the target register class of backend provided in td file. It's used to establish the mapping between
the types of IR values and the number of simultaneous live ranges to which we'd like to limit for some set of those types.
For example, POWER target, register num is special when VSX is enabled. When VSX is enabled, the number of int scalar register is 32(GPR),
float is 64(VSR), but for int and float vector register both are 64(VSR). So there should be 2 kinds of register class when vsx is enabled,
and 3 kinds of register class when VSX is NOT enabled.
It runs on POWER target, it makes big(+~30%) performance improvement in one specific bmk(503.bwaves_r) of spec2017 and no other obvious degressions.
Differential revision: https://reviews.llvm.org/D67148
llvm-svn: 374017
Gather instructions can use i32 or i64 elements for indices. If
the index is zero extended from a type smaller than i32 to i64, we
can shrink the extend to just extend to i32.
llvm-svn: 373982
When the target option GuaranteedTailCallOpt is specified, calls with
the fastcc calling convention will be transformed into tail calls if
they are in tail position. This diff adds a new calling convention,
tailcc, currently supported only on X86, which behaves the same way as
fastcc, except that the GuaranteedTailCallOpt flag does not need to
enabled in order to enable tail call optimization.
Patch by Dwight Guth <dwight.guth@runtimeverification.com>!
Reviewed By: lebedev.ri, paquette, rnk
Differential Revision: https://reviews.llvm.org/D67855
llvm-svn: 373976
Summary:
There was a bug when computing the number of unwind destination
mismatches in CFGStackify. When there are many mismatched calls that
share the same (original) destination BB, they have to be counted
separately.
This also fixes a typo and runs `fixUnwindMismatches` only when the wasm
exception handling is enabled. This is to prevent unnecessary
computations and does not change behavior.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68552
llvm-svn: 373975
Summary:
Previously, `WebAssembly::mayThrow()` assumed all inputs are global
addresses. But when intrinsics, such as `memcpy`, `memmove`, or `memset`
are lowered to external symbols in instruction selection and later
emitted as library calls. And these functions don't throw.
This patch adds handling to those memory intrinsics to `mayThrow`
function. But while most of libcalls don't throw, we can't guarantee all
of them don't throw, so currently we conservatively return true for all
other external symbols.
I think a better way to solve this problem is to embed 'nounwind' info
in `TargetLowering::CallLoweringInfo`, so that we can access the info
from the backend. This will also enable transferring 'nounwind'
properties of LLVM IR instructions. Currently we don't transfer that
info and we can only access properties of callee functions, if the
callees are within the module. Other targets don't need this info in the
backend because they do all the processing before isel, but it will help
us because that info will reduce code size increase in fixing unwind
destination mismatches in CFGStackify.
But for now we return false for these memory intrinsics and true for all
other libcalls conservatively.
Reviewers: dschuff
Subscribers: sbc100, jgravelle-google, hiraditya, sunfish, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68553
llvm-svn: 373967
Start manually writing a table to get the subreg index. TableGen
should probably generate this, but I'm not sure what it looks like in
the arbitrary case where subregisters are allowed to not fully cover
the super-registers.
llvm-svn: 373947
At minimum handle the s64 insert type, which are emitted in real cases
during legalization.
We really need TableGen to emit something to emit something like the
inverse of composeSubRegIndices do determine the subreg index to use.
llvm-svn: 373938
Allows targets to introduce regbankselectable
pseudo-instructions. Currently the closet feature to this is an
intrinsic. However this requires creating a public intrinsic
declaration. This litters the public intrinsic namespace with
operations we don't necessarily want to expose to IR producers, and
would rather leave as private to the backend.
Use a new instruction bit. A previous attempt tried to keep using enum
value ranges, but it turned into a mess.
llvm-svn: 373937
Doing this makes MSVC complain that `empty(someRange)` could refer to
either C++17's std::empty or LLVM's llvm::empty, which previously we
avoided via SFINAE because std::empty is defined in terms of an empty
member rather than begin and end. So, switch callers over to the new
method as it is added.
https://reviews.llvm.org/D68439
llvm-svn: 373935
This ensures that frame-based unwinding will continue to work when
calling a noreturn function; there is not much use having the caller's
frame pointer saved if you don't also have the caller's program counter.
Patch by James Clarke.
Differential Revision: https://reviews.llvm.org/D68542
llvm-svn: 373907
Sam Parker