cover the bitwise operators.
Nothing really exciting here, this just stamps out the rest of the core
operations that can RMW memory and set flags.
Still not implemented here: ADC, SBB. Those will require more
interesting logic to channel the flags *in*, and I'm not currently
planning to try to tackle that. It might be interesting for someone who
wants to improve our code generation for bignum implementations.
Differential Revision: https://reviews.llvm.org/D37141
llvm-svn: 312768
operands and used flags to support matching immediate operands.
This is a bit trickier than register operands, and we still want to fall
back on a register operands even for things that appear to be
"immediates" when they won't actually select into the operation's
immediate operand. This also requires us to handle things like selecting
`sub` vs. `add` to minimize the number of bits needed to represent the
immediate, and picking the shortest immediate encoding. In order to
that, we in turn need to scan to make sure that CF isn't used as it will
get inverted.
The end result seems very nice though, and we're now generating
optimal instruction sequences for these patterns IMO.
A follow-up patch will further expand this to other operations with RMW
memory operands. But handing `add` and `sub` are useful starting points
to flesh out the machinery and make sure interesting and complex cases
can be handled.
Thanks to Craig Topper who provided a few fixes and improvements to this
patch in addition to the review!
Differential Revision: https://reviews.llvm.org/D37139
llvm-svn: 312764
Summary: Knights Landing, because it is Atom derived, has slow two memory operand instructions. Mark the Knights Landing CPU model accordingly.
Patch by David Zarzycki.
Reviewers: craig.topper
Reviewed By: craig.topper
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37224
llvm-svn: 311979
to instructions.
These can't be reasonably matched in tablegen due to the handling of
flags, so we have to do this in C++ code. We only did it for `inc` and
`dec` historically, this starts fleshing that out to more interesting
instructions. Notably, this handles transfering operands to `add` and
`sub`.
Currently this forces them into a register. The next patch will add
support for keeping immediate operands as immediates. Then I'll extend
this beyond just `add` and `sub`.
I'm not super thrilled by the repeated switches in the code but
everything else I tried was really ugly or problematic.
Many thanks to Craig Topper for the suggestions about where to even
begin here and how to make this stuff work.
Differential Revision: https://reviews.llvm.org/D37130
llvm-svn: 311806
to handle other x86 pseudos that carry flags and thus can't be matched
by our ISel patterns with fused memory accesses.
Differential Revision: https://reviews.llvm.org/D37088
llvm-svn: 311749
This extracts the code out of a giant switch in preparation for expanding it to
handle operations other thin `inc` and `dec`. Add a FIXME indicating what's
coming here.
Differential Revision: https://reviews.llvm.org/D37045
llvm-svn: 311748
Summary: With masked operations, its possible for the operation node like fadd, fsub, etc. to be used by multiple different vselects. Since the pattern matching will start at the vselect, we need to make sure the operation node itself is only used once before we can fold a load. Otherwise we'll end up folding the same load into multiple instructions.
Reviewers: RKSimon, spatel, zvi, igorb
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36938
llvm-svn: 311342
We can load the memory VT and check for natural alignment. This also adds a new preferNonTemporalLoad helper that checks the correct subtarget feature based on the load size.
This shrinks the isel table by at least 5000 bytes by allowing more reordering and combining to occur.
llvm-svn: 311266
Masked gather for vector length 2 is lowered incorrectly for element type i32.
The type <2 x i32> was automatically extended to <2 x i64> and we generated VPGATHERQQ instead of VPGATHERQD.
The type <2 x float> is extended to <4 x float>, so there is no bug for this type, but the sequence may be more optimal.
In this patch I'm fixing <2 x i32>bug and optimizing <2 x float> sequence for GATHERs only. The same fix should be done for Scatters as well.
Differential revision: https://reviews.llvm.org/D34343
llvm-svn: 305987
Summary: As per discution on how to get better codegen an large int legalization, it became clear that using a glue for the carry was preventing several desirable optimizations. Passing the carry down as a value allow for more flexibility.
Reviewers: jyknight, nemanjai, mkuper, spatel, RKSimon, zvi, bkramer
Subscribers: igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D29872
llvm-svn: 301775
This patch replaces the separate APInts for KnownZero/KnownOne with a single KnownBits struct. This is similar to what was done to ValueTracking's version recently.
This is largely a mechanical transformation from KnownZero to Known.Zero.
Differential Revision: https://reviews.llvm.org/D32569
llvm-svn: 301620
This will become asan errors once the patch lands that poisons the
memory after free. The x86 change is a hack, but I don't see how to
solve this properly at the moment.
llvm-svn: 300867
For AVX-512 we force the input to zero if the input is undef or the mask is all ones to break an execution dependency. This patch brings the same behavior to AVX2.
llvm-svn: 297652
The Fuchsia ABI defines slots from the thread pointer where the
stack-guard value for stack-protector, and the unsafe stack pointer
for safe-stack, are stored. This parallels the Android ABI support.
Patch by Roland McGrath
Differential Revision: https://reviews.llvm.org/D30237
llvm-svn: 296081
Merging Load-add-store pattern into a increment op previously dropped
the load's chain from the instructions dependence if the store is
chained to a TokenFactor.
llvm-svn: 293892
Summary:
Attaching !absolute_symbol to a global variable does two things:
1) Marks it as an absolute symbol reference.
2) Specifies the value range of that symbol's address.
Teach the X86 backend to allow absolute symbols to appear in place of
immediates by extending the relocImm and mov64imm32 matchers. Start using
relocImm in more places where it is legal.
As previously proposed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105800.html
Differential Revision: https://reviews.llvm.org/D25878
llvm-svn: 289087
Summary: When selectScalarSSELoad is looking for a scalar_to_vector of a scalar load, it makes sure the load is only used by the scalar_to_vector. But it doesn't make sure the scalar_to_vector is only used once. This can cause the same load to be folded multiple times. This can be bad for performance. This also causes the chain output to be duplicated, but not connected to anything so chain dependencies will not be satisfied.
Reviewers: RKSimon, zvi, delena, spatel
Subscribers: andreadb, llvm-commits
Differential Revision: https://reviews.llvm.org/D26790
llvm-svn: 287983
We only ever create TargetConstantPool, TargetJumpTable, TargetExternalSymbol,
TargetGlobalAddress, TargetGlobalTLSAddress, MCSymbol and TargetBlockAddress
nodes as operands of X86ISD::Wrapper nodes, so we can remove one check and
invert the other.
Also update the documentation comment for X86ISD::Wrapper.
Differential Revision: https://reviews.llvm.org/D26731
llvm-svn: 287160
Suspected to be the cause of a sanitizer-windows bot failure:
Assertion failed: isImm() && "Wrong MachineOperand accessor", file C:\b\slave\sanitizer-windows\llvm\include\llvm/CodeGen/MachineOperand.h, line 420
llvm-svn: 286385
A relocatable immediate is either an immediate operand or an operand that
can be relocated by the linker to an immediate, such as a regular symbol
in non-PIC code.
Start using relocImm for 32-bit and 64-bit MOV instructions, and for operands
of type "imm32_su". Remove a number of now-redundant patterns.
Differential Revision: https://reviews.llvm.org/D25812
llvm-svn: 286384
This is a mechanical change of comments in switches like fallthrough,
fall-through, or fall-thru to use the LLVM_FALLTHROUGH macro instead.
llvm-svn: 278902
Summary:
Instead, we take a single flags arg (a bitset).
Also add a default 0 alignment, and change the order of arguments so the
alignment comes before the flags.
This greatly simplifies many callsites, and fixes a bug in
AMDGPUISelLowering, wherein the order of the args to getLoad was
inverted. It also greatly simplifies the process of adding another flag
to getLoad.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, jyknight, dsanders, nemanjai, llvm-commits
Differential Revision: http://reviews.llvm.org/D22249
llvm-svn: 275592
Memory references were not being propagated for this folded load. This
prevented optimizations like LICM from hoisting the load.
Added test to verify that this allows LICM to proceed.
llvm-svn: 273617
The setCallee function will set the number of fixed arguments based
on the size of the argument list. The FixedArgs parameter was often
explicitly set to 0, leading to a lack of consistent value for non-
vararg functions.
Differential Revision: http://reviews.llvm.org/D20376
llvm-svn: 273403
This used to be free, copying and moving DebugLocs became expensive
after the metadata rewrite. Passing by reference eliminates a ton of
track/untrack operations. No functionality change intended.
llvm-svn: 272512
It's very common to want to replace a node and then remove it since
it's dead, especially as we port backends from the SDNode *Select API
to the void Select one. This helper makes this sequence a bit less
verbose.
llvm-svn: 269236
Don't bother returning a result we don't use here. I've also renamed
this from selectGather to tryGather to better indicate that it may not
do anything.
llvm-svn: 269215
Craig Topper