createPSADBW uses SplitsOpsAndApply so should be able to handle
any size.
Restrict the extract result type to i32 or i64 since that's what
we have coverage for today and probably matches what the
isSimple() check gave us before.
Differential Revision: https://reviews.llvm.org/D76560
This patch attempts to more accurately model the reduction of
power of 2 vectors of types we natively support. This takes into
account the narrowing of vectors that occur as we go from 512
bits to 256 bits, to 128 bits. It also takes into account the use
of wider elements in the shuffles for the first 2 steps of a
reduction from 128 bits. And uses a v8i16 shift for the final step
of vXi8 reduction.
The default implementation uses the legalized type for the arithmetic
for all levels. And uses the single source permute cost of the
legalized type for all levels. This penalizes things like
lack of v16i8 pshufb on pre-sse3 targets and the splitting and
joining that needs to be done for integer types on AVX1. We never
need v16i8 shuffle for a reduction and we only need split AVX1 ops
when type the type wide and needs to be split. I think we're still
over costing splits and joins for AVX1, but we're closer now.
I've also removed all pairwise special casing because I don't
think we ever want to generate that on X86. I've also adjusted
the add handling to more accurately account for any type splitting
that occurs before we reach a legal type.
Differential Revision: https://reviews.llvm.org/D76478
This directive inserts code to add $gp to the argument's register when
support for position independent code is enabled.
For example, this code:
.cpadd $4
expands to:
addu $4, $4, $gp
SplitsOpsAndApply will take care of any needed splitting correctly.
All that we need to check is that the vector element count is a
power of 2.
Differential Revision: https://reviews.llvm.org/D76558
D75801 removed the last and only user of this option, so we can
drop it now. The original idea behind this was to only run expensive
transforms under -O3, but apart from the one known bits transform,
this has never really taken off. I believe nowadays the recommendation
is to put expensive transforms in AggressiveInstCombine instead,
though that isn't terribly popular either :)
Differential Revision: https://reviews.llvm.org/D76540
For folding pattern `x-(fma y,z,u*v) -> (fma -y,z,(fma -u,v,x))`, if
`yz` is 1, `uv` is -1 and `x` is -0, sign of result would be changed.
Differential Revision: https://reviews.llvm.org/D76419
Summary:
Avoid blind cast from Operator to ExtractElementInst in
computeKnownBitsFromOperator. This resulted in some crashes
in downstream fuzzy testing. Instead we use getOperand directly
on the Operator when accessing the vector/index operands.
Haven't seen any problems with InsertElement and ShuffleVector,
but I believe those could be used in constant expressions as well.
So the same kind of fix as for ExtractElement was also applied for
InsertElement.
When it comes to ShuffleVector we now simply bail out if a dynamic
cast of the Operator to ShuffleVectorInst fails. I've got no
reproducer indicating problems for ShuffleVector, and a fix would be
slightly more complicated as getShuffleDemandedElts is involved.
Reviewers: RKSimon, nikic, spatel, efriedma
Reviewed By: RKSimon
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D76564
We need to insert into the Visited set at the same time we insert
into the worklist. Otherwise we may end up pushing the same
instruction to the worklist multiple times, and only adding it to
the visited set later.
We often widen xmm/ymm vectors to ymm/zmm by insertion into an undef base vector. By letting getTargetShuffleAndZeroables track the undef elts we can help avoid a lot of unnecessary cross-lane shuffles.
Fixes PR44694
This method it a bit too large.
It is becoming inconvenient to update it.
This patch suggests a way to reduce and cleanup it.
Differential revision: https://reviews.llvm.org/D76499
Now that rG18c19441d105 has improved VPERM2X128 handling, we can perform this to improve x64->x32 truncation without poor cross-lane issues.
Someday combineX86ShufflesRecursively will handle this, but we're still really bad at dealing with different vector widths.
If one operand is unknown (and we don't have nowrap), don't compute
the second operand.
Also don't create an unnecessary extra KnownBits variable, it's
okay to reuse KnownOut.
This reduces instructions on libclamav_md5.c by 40%.
This is the Waymarking algorithm implemented as an independent utility.
The utility is operating on a range of sequential elements.
First we "tag" the elements, by calling `fillWaymarks`.
Then we can "follow" the tags from every element inside the tagged
range, and reach the "head" (the first element), by calling
`followWaymarks`.
Differential Revision: https://reviews.llvm.org/D74415
Technically we can permit EXTLOAD of the LHS operand but only if all the extended bits are shifted out. Until we test coverage for that case, I'm just disabling this to fix PR45265.
