If a fp scalar is loaded and then used as both a scalar and a vector broadcast, perform the load as a broadcast and then extract the scalar for 'free' from the 0th element.
This involved switching the order of the X86ISD::BROADCAST combines so we only convert to X86ISD::BROADCAST_LOAD once all other canonicalizations have been attempted.
Adds a DAGCombinerInfo::recursivelyDeleteUnusedNodes wrapper.
Fixes PR43217
Differential Revision: https://reviews.llvm.org/D68544
llvm-svn: 373871
This is patch aims to group together the `CRNotPat` multi class instantiations
within the `PPCInstrInfo.td` file.
Integer instantiations of the multi class are grouped together into a section,
and the floating point patterns are separated into its own section.
Differential Revision: https://reviews.llvm.org/D67975
llvm-svn: 373869
Replaces setTargetShuffleZeroElements with getTargetShuffleAndZeroables which reports the Zeroable elements but doesn't merge them into the decoded target shuffle mask (the merging has been moved up into getTargetShuffleInputs until we can get rid of it entirely).
This is part of the work to fix PR43024 and allow us to use SimplifyDemandedElts to simplify shuffle chains - we need to get to a point where the target shuffle mask isn't adjusted by its source inputs but instead we cache them in a parallel Zeroable mask.
llvm-svn: 373867
Summary:
The default legalization for v16i64->v16i8 tries to create a multiple stage truncate concatenating after each stage and truncating again. But avx512 implements truncates with multiple uops. So it should be better to truncate all the way to the desired element size and then concatenate the pieces using unpckl instructions. This minimizes the number of 2 uop truncates. The unpcks are all single uop instructions.
I tried to handle this by just custom splitting the v16i64->v16i8 shuffle. And hoped that the DAG combiner would leave the two halves in the state needed to make D68374 do the job for each half. This worked for the first half, but the second half got messed up. So I've implemented custom handling for v8i64->v8i8 when v8i64 needs to be split to produce the VTRUNCs directly.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68428
llvm-svn: 373864
Summary: The VSELECT splitting code tries to split a setcc input as well. But on avx512 where mask registers are well supported it should be better to just split the mask and use a single compare.
Reviewers: RKSimon, spatel, efriedma
Reviewed By: spatel
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68359
llvm-svn: 373863
Summary: The assertion in getLoopGuardBranch can be a 'return nullptr'
under if condition.
Authored By: DTharun
Reviewer: Whitney, fhahn
Reviewed By: Whitney, fhahn
Subscribers: fhahn, llvm-commits
Tag: LLVM
Differential Revision: https://reviews.llvm.org/D66084
llvm-svn: 373857
Removes Programming Documentation page. Also moves existing topics on Programming Documentation page to User Guides and Reference pages.
llvm-svn: 373856
Summary: It ensures that the bswap is generated even when a part of the subtree already matches a bswap transform.
Reviewers: craig.topper, efriedma, RKSimon, lebedev.ri
Subscribers: llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D68250
llvm-svn: 373850
We can make use of the Zeroable mask to indicate which elements we can safely set to zero instead of creating a target shuffle mask on the fly.
This allows us to remove createTargetShuffleMask.
This is part of the work to fix PR43024 and allow us to use SimplifyDemandedElts to simplify shuffle chains - we need to get to a point where the target shuffle masks isn't adjusted by its source inputs in setTargetShuffleZeroElements but instead we cache them in a parallel Zeroable mask.
llvm-svn: 373846
As discussed on PR42025, with more complex boolean math we can end up with many truncations/extensions of the comparison results through each bitop.
This patch handles the cases introduced in combineBitcastvxi1 by pushing the sign extension through the AND/OR/XOR ops so its just the original SETCC ops that gets extended.
Differential Revision: https://reviews.llvm.org/D68226
llvm-svn: 373834
I don't see an ideal solution to these 2 related, potentially large, perf regressions:
https://bugs.llvm.org/show_bug.cgi?id=42708https://bugs.llvm.org/show_bug.cgi?id=43146
We decided that load combining was unsuitable for IR because it could obscure other
optimizations in IR. So we removed the LoadCombiner pass and deferred to the backend.
Therefore, preventing SLP from destroying load combine opportunities requires that it
recognizes patterns that could be combined later, but not do the optimization itself (
it's not a vector combine anyway, so it's probably out-of-scope for SLP).
Here, we add a scalar cost model adjustment with a conservative pattern match and cost
summation for a multi-instruction sequence that can probably be reduced later.
This should prevent SLP from creating a vector reduction unless that sequence is
extremely cheap.
In the x86 tests shown (and discussed in more detail in the bug reports), SDAG combining
will produce a single instruction on these tests like:
movbe rax, qword ptr [rdi]
or:
mov rax, qword ptr [rdi]
Not some (half) vector monstrosity as we currently do using SLP:
vpmovzxbq ymm0, dword ptr [rdi + 1] # ymm0 = mem[0],zero,zero,..
vpsllvq ymm0, ymm0, ymmword ptr [rip + .LCPI0_0]
movzx eax, byte ptr [rdi]
movzx ecx, byte ptr [rdi + 5]
shl rcx, 40
movzx edx, byte ptr [rdi + 6]
shl rdx, 48
or rdx, rcx
movzx ecx, byte ptr [rdi + 7]
shl rcx, 56
or rcx, rdx
or rcx, rax
vextracti128 xmm1, ymm0, 1
vpor xmm0, xmm0, xmm1
vpshufd xmm1, xmm0, 78 # xmm1 = xmm0[2,3,0,1]
vpor xmm0, xmm0, xmm1
vmovq rax, xmm0
or rax, rcx
vzeroupper
ret
Differential Revision: https://reviews.llvm.org/D67841
llvm-svn: 373833
Rename some variables to match lowerShuffleAsRepeatedMaskAndLanePermute - prep work toward adding some equivalent sublane functionality.
llvm-svn: 373832
Added some tests testing urem and srem operations with a constant divisor.
Patch by TG908 (Tim Gymnich)
Differential Revision: https://reviews.llvm.org/D68421
llvm-svn: 373830
This looks like a defect in gcc-5 where it chooses a constexpr
constructor from the initializer-list that it considers to be explicit.
I've tried to reproduce but I can't install anything prior to gcc-6 easily
on my system, and that doesn't have the error. So this is speculative
pacification.
Reported by Steven Wan.
llvm-svn: 373820
The motivation is to reuse the key value parsing logic here to
parse instance specific pass options within the context of MLIR.
The primary functionality exposed is the "," splitting for
arrays and the logic for properly handling duplicate definitions
of a single flag.
Patch by: Parker Schuh <parkers@google.com>
Differential Revision: https://reviews.llvm.org/D68294
llvm-svn: 373815
This is an omission in rL371441. Loads which happened to be unordered weren't being added to the PendingLoad set, and thus weren't be ordered w/respect to side effects which followed before the end of the block.
Included test case is how I spotted this. We had an atomic load being folded into a using instruction after a fence that load was supposed to be ordered with. I'm sure it showed up a bunch of other ways as well.
Spotted via manual inspecting of assembly differences in a corpus w/and w/o the new experimental mode. Finding this with testing would have been "unpleasant".
llvm-svn: 373814
This reverts r371177 (git commit f879c6875563c0a8cd838f1e13b14dd33558f1f8)
It caused PR43566 by removing empty, address-taken MachineBasicBlocks.
Such blocks may have references from blockaddress or other operands, and
need more consideration to be removed.
See the PR for a test case to use when relanding.
llvm-svn: 373805
We do indeed already get it right in some cases, but only transitively,
with one-use restrictions. Since we only need to produce a single
comparison, it makes sense to match the pattern directly:
https://rise4fun.com/Alive/kPg
llvm-svn: 373802
Initially (D65380) i believed that if we have rightshift-trunc-rightshift,
we can't do any folding. But as it usually happens, i was wrong.
https://rise4fun.com/Alive/GEwhttps://rise4fun.com/Alive/gN2O
In https://bugs.llvm.org/show_bug.cgi?id=43564 we happen to have
this very sequence, of two right shifts separated by trunc.
And "just" so that happens, we apparently can fold the pattern
if the total shift amount is either 0, or it's equal to the bitwidth
of the innermost widest shift - i.e. if we are left with only the
original sign bit. Which is exactly what is wanted there.
llvm-svn: 373801