Daniel Sanders [Thu, 3 Oct 2019 01:04:42 +0000 (01:04 +0000)]
[gicombiner] Add a CodeExpander to handle C++ fragments with variable expansion
Summary:
This will handle expansion of C++ fragments in the declarative combiner
including custom predicates, and escapes into C++ to aid the migration
effort.
When SIFixSGPRCopies attempts to fix an illegal copy from vector to
scalar register it calls moveToVALU(). A copy from an agpr to sgpr
becomes a copy from agpr to agpr, which may result in the illegal
register class at a use of this copy.
Solution is to copy it always into a vgpr. This may result in a
subsequent copy into an agpr if that is what really needed, however
should not happen too often and likely will be folded later.
The opposite situation may not happen because an sgpr is always
illegal where agpr is legal, so such user instructions may not
exist.
Roman Lebedev [Wed, 2 Oct 2019 23:02:12 +0000 (23:02 +0000)]
[InstCombine] Bypass high bit extract before variable sign-extension (PR43523)
https://rise4fun.com/Alive/8BY - valid for lshr+trunc+variable sext
https://rise4fun.com/Alive/7jk - the variable sext can be redundant
https://rise4fun.com/Alive/Qslu - 'exact'-ness of first shift can be preserver
https://rise4fun.com/Alive/IF63 - without trunc we could view this as
more general "drop redundant mask before right-shift",
but let's handle it here for now
https://rise4fun.com/Alive/iip - likewise, without trunc, variable sext can be redundant.
There's more patterns for sure - e.g. we can have 'lshr' as the final shift,
but that might be best handled by some more generic transform, e.g.
"drop redundant masking before right-shift" (PR42456)
I'm singling-out this sext patch because you can only extract
high bits with `*shr` (unlike abstract bit masking),
and i *know* this fold is wanted by existing code.
I don't believe there is much to review here,
so i'm gonna opt into post-review mode here.
David Blaikie [Wed, 2 Oct 2019 22:58:02 +0000 (22:58 +0000)]
DebugInfo: Rename DebugLocStream::Entry::Begin/EndSym to just Begin/End
Brings this struct in line with the RangeSpan class so they might
eventually be used by common template code for generating range/loc
lists with less duplicate code.
David Bolvansky [Wed, 2 Oct 2019 22:49:20 +0000 (22:49 +0000)]
[InstCombine] Transform bcopy to memmove
bcopy is still widely used mainly for network apps. Sadly, LLVM has no optimizations for bcopy, but there are some for memmove.
Since bcopy == memmove, it is profitable to transform bcopy to memmove and use current optimizations for memmove for free here.
David Blaikie [Wed, 2 Oct 2019 22:27:24 +0000 (22:27 +0000)]
DebugInfo: Simplify RangeSpan to be a plain struct
This is an effort to make RangeSpan and DebugLocStream::Entry more
similar to share code for their emission (to reuse the more complicated
code for using (& choosing when to use) base address selection entries,
etc).
It didn't seem like this struct was worth the complexity of
encapsulation - when the members could be initialized by the ctor to any
value (no validation) and the type is assignable (so there's no
mutability or other constraint being implemented by its interface).
Daniel Sanders [Wed, 2 Oct 2019 21:13:07 +0000 (21:13 +0000)]
[gicombiner] Add the boring boilerplate for the declarative combiner
Summary:
This is the first of a series of patches extracted from a much bigger WIP
patch. It merely establishes the tblgen pass and the way empty combiner
helpers are declared and integrated into a combiner info.
The tablegen pass takes a -combiners option to select the combiner helper
that will be generated. This can be given multiple values to generate
multiple combiner helpers at once. Doing so helps to minimize parsing
overhead.
The reason for creating a GlobalISel subdirectory in utils/TableGen is that
there will be quite a lot of non-pass files (~15) by the time the patch
series is done.
Yi-Hong Lyu [Wed, 2 Oct 2019 20:25:16 +0000 (20:25 +0000)]
[PowerPC] Fix SH field overflow issue
Store rlwinm Rx, Ry, 32, 0, 31 as rlwinm Rx, Ry, 0, 0, 31 and store
rldicl Rx, Ry, 64, 0 as rldicl Rx, Ry, 0, 0. Otherwise SH field is overflow and
fails assertion in assembly printing stage.
Alina Sbirlea [Wed, 2 Oct 2019 18:42:33 +0000 (18:42 +0000)]
[MemorySSA] Update Phi creation when inserting a Def.
MemoryPhis should be added in the IDF of the blocks newly gaining Defs.
This includes the blocks that gained a Phi and the block gaining a Def,
if the block did not have one before.
Resolves PR43427.
Craig Topper [Wed, 2 Oct 2019 17:47:09 +0000 (17:47 +0000)]
[X86] Rewrite to the vXi1 subvector insertion code to not rely on the value of bits that might be undef
The previous code tried to do a trick where we would extract the subvector from the location we were inserting. Then xor that with the new value. Take the xored value and clear out the bits above the subvector size. Then shift that xored subvector to the insert location. And finally xor that with the original vector. Since the old subvector was used in both xors, this would leave just the new subvector at the inserted location. Since the surrounding bits had been zeroed no other bits of the original vector would be modified.
Unfortunately, if the old subvector came from undef we might aggressively propagate the undef. Then we end up with the XORs not cancelling because they aren't using the same value for the two uses of the old subvector. @bkramer gave me a case that demonstrated this, but we haven't reduced it enough to make it easily readable to see what's happening.
This patch uses a safer, but more costly approach. It isolate the bits above the insertion and bits below the insert point and ORs those together leaving 0 for the insertion location. Then widens the subvector with 0s in the upper bits, shifts it into position with 0s in the lower bits. Then we do another OR.
Thomas Lively [Wed, 2 Oct 2019 17:34:44 +0000 (17:34 +0000)]
[WebAssembly] Error when using wasm64 for ISel
Summary:
64-bit WebAssembly (wasm64) is not specified and not supported in the
WebAssembly backend. We do have support for it in clang, however, and
we would like to keep that support because we expect wasm64 to be
specified and supported in the future. For now add an error when
trying to use wasm64 from the backend to minimize user confusion from
unexplained crashes.
Piotr Sobczak [Wed, 2 Oct 2019 17:22:36 +0000 (17:22 +0000)]
[AMDGPU] Extend buffer intrinsics with swizzling
Summary:
Extend cachepolicy operand in the new VMEM buffer intrinsics
to supply information whether the buffer data is swizzled.
Also, propagate this information to MIR.
Furthermore, disable merging of VMEM buffer instructions
in SI Load/Store optimizer, if the "swizzled" bit on the instruction
is on.
The default value of the bit is 0, meaning that data in buffer
is linear and buffer instructions can be merged.
There is no difference in the generated code with this commit.
However, in the future it will be expected that front-ends
use buffer intrinsics with correct "swizzled" bit set.
Teresa Johnson [Wed, 2 Oct 2019 16:36:59 +0000 (16:36 +0000)]
[ThinLTO/WPD] Ensure devirtualized targets use promoted symbol when necessary
Summary:
This fixes a hole in the handling of devirtualized targets that were
local but need promoting due to devirtualization in another module. We
were not correctly referencing the promoted symbol in some cases. Make
sure the code that updates the name also looks at the ExportedGUIDs set
by utilizing a callback that checks all conditions (the callback
utilized by the internalization/promotion code).
As noted on PR41772, the static analyzer reports that the MachineMemOperand::print partial wrappers set a number of args to null pointers that were then dereferenced in the actual implementation.
It turns out that these wrappers are not being used at all (hence why we're not seeing any crashes), so I'd like to propose we just get rid of them.
Michal Gorny [Wed, 2 Oct 2019 16:06:50 +0000 (16:06 +0000)]
[llvm] [cmake] Add install targets for missing distribution components
Add install targets as necessary to include all files normally installed
in LLVM_DISTRIBUTION_COMPONENTS. This includes targets for Sphinx docs,
opt-viewer Python modules and TableGens.
The static analyzer is warning about a potential null dereference, but we should be able to use cast<PHINode> directly and if not assert will fire for us.
Hans Wennborg [Wed, 2 Oct 2019 14:35:06 +0000 (14:35 +0000)]
Reapply r373431 "Switch lowering: omit range check for bit tests when default is unreachable (PR43129)"
This was reverted in r373454 due to breaking the expensive-checks bot.
This version addresses that by omitting the addSuccessorWithProb() call
when omitting the range check.
> Switch lowering: omit range check for bit tests when default is unreachable (PR43129)
>
> This is modeled after the same functionality for jump tables, which was
> added in r357067.
>
> Differential revision: https://reviews.llvm.org/D68131
The static analyzer is warning about a potential null dereference, but we should be able to use cast<MemoryAccess> directly and if not assert will fire for us.
The static analyzer is warning about potential null dereferences, but in these cases we should be able to use cast<SCEVConstant> directly and if not assert will fire for us.
James Molloy [Wed, 2 Oct 2019 12:46:44 +0000 (12:46 +0000)]
[ModuloSchedule] Peel out prologs and epilogs, generate actual code
Summary:
This extends the PeelingModuloScheduleExpander to generate prolog and epilog code,
and correctly stitch uses through the prolog, kernel, epilog DAG.
The key concept in this patch is to ensure that all transforms are *local*; only a
function of a block and its immediate predecessor and successor. By defining the problem in this way
we can inductively rewrite the entire DAG using only local knowledge that is easy to
reason about.
For example, we assume that all prologs and epilogs are near-perfect clones of the
steady-state kernel. This means that if a block has an instruction that is predicated out,
we can redirect all users of that instruction to that equivalent instruction in our
immediate predecessor. As all blocks are clones, every instruction must have an equivalent in
every other block.
Similarly we can make the assumption by construction that if a value defined in a block is used
outside that block, the only possible user is its immediate successors. We maintain this
even for values that are used outside the loop by creating a limited form of LCSSA.
This code isn't small, but it isn't complex.
Enabled a bunch of testing from Hexagon. There are a couple of tests not enabled yet;
I'm about 80% sure there isn't buggy codegen but the tests are checking for patterns
that we don't produce. Those still need a bit more investigation. In the meantime we
(Google) are happy with the code produced by this on our downstream SMS implementation,
and believe it generates correct code.
Florian Hahn [Wed, 2 Oct 2019 12:32:52 +0000 (12:32 +0000)]
[InstCombine] Simplify fma multiplication to nan for undef or nan operands.
In similar fashion to D67721, we can simplify FMA multiplications if any
of the operands is NaN or undef. In instcombine, we will simplify the
FMA to an fadd with a NaN operand, which in turn gets folded to NaN.
Note that this just changes SimplifyFMAFMul, so we still not catch the
case where only the Add part of the FMA is Nan/Undef.
Sanjay Patel [Wed, 2 Oct 2019 12:12:02 +0000 (12:12 +0000)]
[InstSimplify] fold fma/fmuladd with a NaN or undef operand
This is intended to be similar to the constant folding results from
D67446
and earlier, but not all operands are constant in these tests, so the
responsibility for folding is left to InstSimplify.
Hans Wennborg [Wed, 2 Oct 2019 12:08:44 +0000 (12:08 +0000)]
Revert r373431 "Switch lowering: omit range check for bit tests when default is unreachable (PR43129)"
This broke http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/19967
> Switch lowering: omit range check for bit tests when default is unreachable (PR43129)
>
> This is modeled after the same functionality for jump tables, which was
> added in r357067.
>
> Differential revision: https://reviews.llvm.org/D68131
The static analyzer is warning about a potential null dereference, but we should be able to use cast<Function> directly and if not assert will fire for us.
The static analyzer is warning about a potential null dereference, but we know that the source won't be null so just use dyn_cast, which will assert if the value somehow is actually null.
David Green [Wed, 2 Oct 2019 11:40:51 +0000 (11:40 +0000)]
[ARM] Identity shuffles are legal
Identity shuffles, of the form (0, 1, 2, 3, ...) are perfectly OK under MVE
(they essentially just become bitcasts). We were not catching that in the
existing set of what we considered legal though. On NEON, they would be covered
by vext's, but that is not generally available in MVE.
This uses ShuffleVectorInst::isIdentityMask which is a little odd to use here
but does what we want and prevents us from just rewriting what is the same
function.
[IntrinsicEmitter] Add overloaded type VecOfBitcastsToInt for SVE intrinsics
Summary:
This allows intrinsics such as the following to be defined:
- declare <n x 4 x i32> @llvm.something.nxv4f32(<n x 4 x i32>, <n x 4 x i1>, <n x 4 x float>)
...where <n x 4 x i32> is derived from <n x 4 x float>, but
the element needs bitcasting to int.
Jay Foad [Wed, 2 Oct 2019 08:44:15 +0000 (08:44 +0000)]
[AMDGPU] Make printf lowering faster when there are no printfs
Summary:
Printf lowering unconditionally visited every instruction in the module.
To make it faster in the common case where there are no printfs, look up
the printf function (if any) and iterate over its users instead.
Florian Hahn [Wed, 2 Oct 2019 07:37:41 +0000 (07:37 +0000)]
[Local] Simplify function removeUnreachableBlocks() to avoid (re-)computation.
Two small changes in llvm::removeUnreachableBlocks() to avoid unnecessary (re-)computation.
First, replace the use of count() with find(), which has better time complexity.
Second, because we have already computed the set of dead blocks, replace the second loop over all basic blocks to a loop only over the already computed dead blocks. This simplifies the loop and avoids recomputation.
Patch by Rodrigo Caetano Rocha <rcor.cs@gmail.com>
The tool reports verbose output for the DWARF debug location coverage.
The llvm-locstats for each variable or formal parameter DIE computes what
percentage from the code section bytes, where it is in scope, it has
location description. The line 0 shows the number (and the percentage) of
DIEs with no location information, but the line 100 shows the number (and
the percentage) of DIEs where there is location information in all code
section bytes (where the variable or parameter is in the scope). The line
50..59 shows the number (and the percentage) of DIEs where the location
information is in between 50 and 59 percentage of its scope covered.
Rui Ueyama [Wed, 2 Oct 2019 05:24:24 +0000 (05:24 +0000)]
[llvm-lib] Correctly handle .lib input files
If archive files are passed as input files, llvm-lib needs to append
the members of the input archive files to the output file. This patch
implements that behavior.
This patch splits an existing function into smaller functions.
Effectively, the new code is only `if (Magic == file_magic::archive)
{ ... }` part.
Craig Topper [Wed, 2 Oct 2019 04:45:02 +0000 (04:45 +0000)]
[X86] Add broadcast load folding patterns to the NoVLX compare patterns.
These patterns use zmm registers for 128/256-bit compares when
the VLX instructions aren't available. Previously we only
supported registers, but as PR36191 notes we can fold broadcast
loads, but not regular loads.
Matt Arsenault [Wed, 2 Oct 2019 01:02:24 +0000 (01:02 +0000)]
AMDGPU/GlobalISel: Assume VGPR for G_FRAME_INDEX
In principle this should behave as any other constant. However
eliminateFrameIndex currently assumes a VALU use and uses a vector
shift. Work around this by selecting to VGPR for now until
eliminateFrameIndex is fixed.
Craig Topper [Tue, 1 Oct 2019 23:18:31 +0000 (23:18 +0000)]
[X86] Add a DAG combine to shrink vXi64 gather/scatter indices that are constant with sufficient sign bits to fit in vXi32
The gather/scatter instructions can implicitly sign extend the indices. If we're operating on 32-bit data, an v16i64 index can force a v16i32 gather to be split in two since the index needs 2 registers. If we can shrink the index to the i32 we can avoid the split. It should always be safe to shrink the index regardless of the number of elements. We have gather/scatter instructions that can use v2i32 index stored in a v4i32 register with v2i64 data size.
I've limited this to before legalize types to avoid creating a v2i32 after type legalization. We could check for it, but we'd also need testing. I'm also only handling build_vectors with no bitcasts to be sure the truncate will constant fold.
Craig Topper [Tue, 1 Oct 2019 22:40:03 +0000 (22:40 +0000)]
Revert r373172 "[X86] Add custom isel logic to match VPTERNLOG from 2 logic ops."
This seems to be causing some performance regresions that I'm
trying to investigate.
One thing that stands out is that this transform can increase
the live range of the operands of the earlier logic op. This
can be bad for register allocation. If there are two logic
op inputs we should really combine the one that is closest, but
SelectionDAG doesn't have a good way to do that. Maybe we need
to do this as a basic block transform in Machine IR.
[FileCheck] Move private interface to its own header
Summary:
Most of the class definition in llvm/include/llvm/Support/FileCheck.h
are actually implementation details that should not be relied upon. This
commit moves all of it in a new header file under
llvm/lib/Support/FileCheck. It also takes advantage of the code movement
to put the code into a new llvm::filecheck namespace.
Leonard Chan [Tue, 1 Oct 2019 20:49:07 +0000 (20:49 +0000)]
[ASan][NFC] Address remaining comments for https://reviews.llvm.org/D68287
I submitted that patch after I got the LGTM, but the comments didn't
appear until after I submitted the change. This adds `const` to the
constructor argument and makes it a pointer.
Leonard Chan [Tue, 1 Oct 2019 20:30:46 +0000 (20:30 +0000)]
[ASan] Make GlobalsMD member a const reference.
PR42924 points out that copying the GlobalsMetadata type during
construction of AddressSanitizer can result in exteremely lengthened
build times for translation units that have many globals. This can be addressed
by just making the GlobalsMD member in AddressSanitizer a reference to
avoid the copy. The GlobalsMetadata type is already passed to the
constructor as a reference anyway.
Bardia Mahjour [Tue, 1 Oct 2019 19:32:42 +0000 (19:32 +0000)]
[DDG] Data Dependence Graph - Root Node
Summary:
This patch adds Root Node to the DDG. The purpose of the root node is to create a single entry node that allows graph walk iterators to iterate through all nodes of the graph, making sure that no node is left unvisited during a graph walk (eg. SCC or DFS). Once the DDG is fully constructed it will have exactly one root node. Every node in the graph is reachable from the root. The algorithm for connecting the root node is based on depth-first-search that keeps track of visited nodes to try to avoid creating unnecessary edges.
Alina Sbirlea [Tue, 1 Oct 2019 19:09:50 +0000 (19:09 +0000)]
[MemorySSA] Check for unreachable blocks when getting last definition.
If a single predecessor is found, still check if the block is
unreachable. The test that found this had a self loop unreachable block.
Resolves PR43493.
projects / llvm / log