Andrea Di Biagio [Mon, 21 Jan 2019 12:04:10 +0000 (12:04 +0000)]
[X86][BtVer2] Update the WriteLoad latency.
r327630 introduced new write definitions for float/vector loads.
Before that revision, WriteLoad was used by both integer/float (scalar/vector)
load. So, WriteLoad had to conservatively declare a latency to 5cy. That is
because the load-to-use latency for float/vector load is 5cy.
Now that we have dedicated writes for float/vector loads, there is no reason why
we should keep the latency of WriteLoad to 5cy. At the moment, WriteLoad is only
used by scalar integer loads only; we can assume an optimstic 3cy latency for
them.
This patch changes that latency from 5cy to 3cy, and regenerates the affected
scheduling/mca tests.
Chandler Carruth [Mon, 21 Jan 2019 09:52:34 +0000 (09:52 +0000)]
Fix typos throughout the license files that somehow I and my reviewers
all missed!
Thanks to Alex Bradbury for pointing this out, and the fact that I never
added the intended `legacy` anchor to the developer policy. Add that
anchor too. With hope, this will cause the links to all resolve
successfully.
This patch introduces the field `ExpressionSize` in SCEV. This field is
calculated only once on SCEV creation, and it represents the complexity of
this SCEV from arithmetical point of view (not from the point of the number
of actual different SCEV nodes that are used in the expression). Roughly
saying, it is the number of operands and operations symbols when we print this
SCEV.
A formal definition is following: if SCEV `X` has operands
`Op1`, `Op2`, ..., `OpN`,
then
Size(X) = 1 + Size(Op1) + Size(Op2) + ... + Size(OpN).
Size of SCEVConstant and SCEVUnknown is one.
Expression size may be used as a universal way to limit SCEV transformations
for huge SCEVs. Currently, we have a bunch of options that represents various
limits (such as recursion depth limit) that may not make any sense from the
point of view of a LLVM users who is not familiar with SCEV internals, and all
these different options pursue one goal. A more general rule that may
potentially allow us to get rid of this redundancy in options is "do not make
transformations with SCEVs of huge size". It can apply to all SCEV traversals
and transformations that may need to visit a SCEV node more than once, hence
they are prone to combinatorial explosions.
This patch only introduces SCEV sizes calculation as NFC, its utilization will
be introduced in follow-up patches.
Dylan McKay [Mon, 21 Jan 2019 04:32:02 +0000 (04:32 +0000)]
[AVR] Insert unconditional branch when inserting MBBs between blocks with fallthrough
This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.
Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.
The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.
This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.
Thanks to Carl Peto for reporting this bug.
This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.
Dylan McKay [Mon, 21 Jan 2019 02:44:09 +0000 (02:44 +0000)]
[AVR] Insert unconditional branch when inserting MBBs between blocks with fallthrough
This updates the AVR Select8/Select16 expansion code so that, when
inserting the two basic blocks for true and false conditions, any
existing fallthrough on the previous block is preserved.
Prior to this patch, if the block before the Select pseudo fell through
to the subsequent block, two new basic blocks would be inserted at the
prior fallthrough point, changing the fallthrough destination.
The predecessor or successor lists were not updated, causing the
BranchFolding pass at -O1 and above the rearrange basic blocks, causing
an infinite loop. Not to mention the unconditional fallthrough to the
true block is incorrect in of itself.
This patch modifies the Select8/16 expansion so that, if inserting true
and false basic blocks at a fallthrough point, the implicit branch is
preserved by means of an explicit, unconditional branch to the previous
fallthrough destination.
Thanks to Carl Peto for reporting this bug.
This fixes avr-rust bug https://github.com/avr-rust/rust/issues/123.
Serge Guelton [Sun, 20 Jan 2019 21:19:56 +0000 (21:19 +0000)]
Replace llvm::isPodLike<...> by llvm::is_trivially_copyable<...>
As noted in https://bugs.llvm.org/show_bug.cgi?id=36651, the specialization for
isPodLike<std::pair<...>> did not match the expectation of
std::is_trivially_copyable which makes the memcpy optimization invalid.
This patch renames the llvm::isPodLike trait into llvm::is_trivially_copyable.
Unfortunately std::is_trivially_copyable is not portable across compiler / STL
versions. So a portable version is provided too.
Note that the following specialization were invalid:
std::pair<T0, T1>
llvm::Optional<T>
Tests have been added to assert that former specialization are respected by the
standard usage of llvm::is_trivially_copyable, and that when a decent version
of std::is_trivially_copyable is available, llvm::is_trivially_copyable is
compared to std::is_trivially_copyable.
As of this patch, llvm::Optional is no longer considered trivially copyable,
even if T is. This is to be fixed in a later patch, as it has impact on a
long-running bug (see r347004)
Note that GCC warns about this UB, but this got silented by https://reviews.llvm.org/D50296.
Simon Pilgrim [Sun, 20 Jan 2019 19:27:40 +0000 (19:27 +0000)]
[X86] Auto upgrade VPCOM/VPCOMU intrinsics to generic integer comparisons
This causes a couple of changes in the upgrade tests as signed/unsigned eq/ne are equivalent and we constant fold true/false codes, these changes are the same as what we already do for avx512 cmp/ucmp.
Noticed while cleaning up vector integer comparison costs for PR40376.
Matt Arsenault [Sun, 20 Jan 2019 18:40:36 +0000 (18:40 +0000)]
AMDGPU/GlobalISel: Fix some crashs in g_unmerge_values/g_merge_values
This was crashing in the predicate function assuming the value
is a vector.
Copy more of what AArch64 uses. This probably needs more refinement
later, but I don't exactly understand what it means in some cases,
particularly since any legalization for these seems to be missing.
Simon Pilgrim [Sun, 20 Jan 2019 17:36:22 +0000 (17:36 +0000)]
[X86] Auto upgrade old style VPCOM/VPCOMU intrinsics to generic integer comparisons
We were upgrading these to the new style VPCOM/VPCOMU intrinsics (which includes the condition code immediate), but we'll be getting rid of those shortly, so convert these to generics first.
This causes a couple of changes in the upgrade tests as signed/unsigned eq/ne are equivalent and we constant fold true/false codes, these changes are the same as what we already do for avx512 cmp/ucmp.
Noticed while cleaning up vector integer comparison costs for PR40376.
Simon Pilgrim [Sun, 20 Jan 2019 13:55:01 +0000 (13:55 +0000)]
[CostModel][X86] Add explicit vector select costs
Prior to SSE41 (and sometimes on AVX1), vector select has to be performed as a ((X & C)|(Y & ~C)) bit select.
Exposes a couple of issues with the min/max reduction costs (which only go down to SSE42 for some reason).
The increase pre-SSE41 selection costs also prevent a couple of tests from firing any longer, so I've either tweaked the target or added AVX tests as well to the existing SSE2 tests.
Dylan McKay [Sun, 20 Jan 2019 11:12:39 +0000 (11:12 +0000)]
[AVR] Allow AVR to be explicitly set as the default target triple
This extends the CMake cross compilation logic so that AVR can be set as
the default target triple, and thus the generic codegen tests can be
run.
This used to be possible on AVR; the CMake configuration files have
since been changed.
With this patch, 'cmake -DLLVM_DEFAULT_TARGET_TRIPLE=avr-unknown-unknown' can
be passed on the command line, making the `-mcpu` argument redundant to
'llc' and friends.
Dylan McKay [Sun, 20 Jan 2019 03:41:08 +0000 (03:41 +0000)]
[AVR] Fix codegen bug in 16-bit loads
Prior to this patch, the AVR::LDWRdPtr instruction was always lowered to
instructions of this pattern:
ld $GPR8, [PTR:XYZ]+
ld $GPR8, [PTR]+1
This has a problem; the [PTR] is incremented in-place once, but never
decremented.
Future uses of the same pointer will use the now clobbered value,
leading to the pointer being incorrect by an offset of one.
This patch modifies the expansion code of the LDWRdPtr pseudo
instruction so that the pointer variable is not silently clobbered in
future uses in the same live range.
Chandler Carruth [Sat, 19 Jan 2019 11:30:51 +0000 (11:30 +0000)]
Update structured references to the license to the new license.
Since these are intended to be short and succinct, I've used the SPDX
full name. It's human readable, but formally agreed upon and will be
part of the SPDX spec for licenses.
Chandler Carruth [Sat, 19 Jan 2019 10:56:40 +0000 (10:56 +0000)]
Update more file headers across all of the LLVM projects in the monorepo
to reflect the new license. These used slightly different spellings that
defeated my regular expressions.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
Chandler Carruth [Sat, 19 Jan 2019 08:50:56 +0000 (08:50 +0000)]
Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
Chandler Carruth [Sat, 19 Jan 2019 06:36:08 +0000 (06:36 +0000)]
Convert two more files that were using Windows line endings and remove
a stray single '\r' from one file. These are the last line ending issues
I can find in the files containing parts of LLVM's file headers.
Chandler Carruth [Sat, 19 Jan 2019 06:14:24 +0000 (06:14 +0000)]
Install new LLVM license structure and new developer policy.
This installs the new developer policy and moves all of the license
files across all LLVM projects in the monorepo to the new license
structure. The remaining projects will be moved independently.
Note that I've left odd formatting and other idiosyncracies of the
legacy license structure text alone to make the diff easier to read.
Critically, note that we do not in any case *remove* the old license
notice or terms, as that remains necessary until we finish the
relicensing process.
I've updated a few license files that refer to the LLVM license to
instead simply refer generically to whatever license the LLVM project is
under, basically trying to minimize confusion.
This is really the culmination of so many people. Chris led the
community discussions, drafted the policy update and organized the
multi-year string of meeting between lawyers across the community to
figure out the strategy. Numerous lawyers at companies in the community
spent their time figuring out initial answers, and then the Foundation's
lawyer Heather Meeker has done *so* much to help refine and get us ready
here. I could keep going on, but I just want to make sure everyone
realizes what a huge community effort this has been from the begining.
Enable IPConstantPropagation to work with abstract call sites
This modification of the currently unused inter-procedural constant
propagation pass (IPConstantPropagation) shows how abstract call sites
enable optimization of callback calls alongside direct and indirect
calls. Through minimal changes, mostly dealing with the partial mapping
of callbacks, inter-procedural constant propagation was enabled for
callbacks, e.g., OpenMP runtime calls or pthreads_create.
AbstractCallSite -- A unified interface for (in)direct and callback calls
An abstract call site is a wrapper that allows to treat direct,
indirect, and callback calls the same. If an abstract call site
represents a direct or indirect call site it behaves like a stripped
down version of a normal call site object. The abstract call site can
also represent a callback call, thus the fact that the initially
called function (=broker) may invoke a third one (=callback callee).
In this case, the abstract call side hides the middle man, hence the
broker function. The result is a representation of the callback call,
inside the broker, but in the context of the original instruction that
invoked the broker.
Again, there are up to three functions involved when we talk about
callback call sites. The caller (1), which invokes the broker
function. The broker function (2), that may or may not invoke the
callback callee. And finally the callback callee (3), which is the
target of the callback call.
The abstract call site will handle the mapping from parameters to
arguments depending on the semantic of the broker function. However,
it is important to note that the mapping is often partial. Thus, some
arguments of the call/invoke instruction are mapped to parameters of
the callee while others are not. At the same time, arguments of the
callback callee might be unknown, thus "null" if queried.
This patch introduces also !callback metadata which describe how a
callback broker maps from parameters to arguments. This metadata is
directly created by clang for known broker functions, provided through
source code attributes by the user, or later deduced by analyses.
For motivation and additional information please see the corresponding
talk (slides/video)
https://llvm.org/devmtg/2018-10/talk-abstracts.html#talk20
as well as the LCPC paper
http://compilers.cs.uni-saarland.de/people/doerfert/par_opt_lcpc18.pdf
Reid Kleckner [Sat, 19 Jan 2019 00:33:02 +0000 (00:33 +0000)]
[X86] Deduplicate static calling convention helpers for code size, NFC
Summary:
Right now we include ${TGT}GenCallingConv.inc once per each instruction
selection method implemented by ${TGT}:
- ${TGT}ISelLowering.cpp
- ${TGT}CallLowering.cpp
- ${TGT}FastISel.cpp
Instead, add a mechanism to tablegen for marking a particular convention
as "External", which causes tablegen to emit into the ::llvm namespace,
instead of as a static helper. This allows us to provide a header to
forward declare it, so we can simply call the function from all the
places it is referenced. Typically the calling convention analyzer is
called indirectly, so it doesn't benefit from inlining.
This saves a bit of final binary size, but mostly just saves object file
size:
before after diff artifact
12852K 12492K -360K X86ISelLowering.cpp.obj
4640K 4280K -360K X86FastISel.cpp.obj
1704K 2092K +388K X86CallingConv.cpp.obj
52448K 52336K -112K llc.exe
I didn't collect before numbers for X86CallLowering.cpp.obj, which is
for GlobalISel, but we should save 360K there as well.
This patch applies the strategy to the X86 backend, but there is no
reason it couldn't be applied to the other backends that implement
multiple ISel strategies, like AArch64.
Nico Weber [Sat, 19 Jan 2019 00:10:54 +0000 (00:10 +0000)]
Use llvm_canonicalize_cmake_booleans for LLVM_LIBXML2_ENABLED [llvm]
r291284 added a nice mechanism to consistently pass CMake on/off toggles to
lit. This change uses it for LLVM_LIBXML2_ENABLED too (which was added around
the same time and doesn't use the new system yet).
Also alphabetically sort the list passed to llvm_canonicalize_cmake_booleans()
in llvm/test/CMakeLists.txt.
Sanjay Patel [Fri, 18 Jan 2019 20:42:12 +0000 (20:42 +0000)]
[x86] add more movmsk tests; NFC
The existing tests already show a sub-optimal transform,
but this should make it clear that we can't just match
an 'and' op when creating movmsk instructions.
Craig Topper [Fri, 18 Jan 2019 20:14:46 +0000 (20:14 +0000)]
[X86] Lower avx512f scatter intrinsics to X86MaskedScatterSDNode instead of going directly to MachineSDNode.
This sends these intrinsics through isel in a much more normal way. This should allow addressing mode matching in isel to make better use of the displacement field.
Roman Tereshin [Fri, 18 Jan 2019 20:13:42 +0000 (20:13 +0000)]
[CGP] Check for existing inttotpr before creating new one
Make sure CodeGenPrepare doesn't emit multiple inttoptr instructions of
the same integer value while sinking address computations, but rather
CSEs them on the fly: excessive inttoptr's confuse SCEV into thinking
that related pointers have nothing to do with each other.
This problem blocks LoadStoreVectorizer from vectorizing some of the
loads / stores in a downstream target.
Bjorn Pettersson [Fri, 18 Jan 2019 20:06:13 +0000 (20:06 +0000)]
[SelectionDAG] Updates for -dag-dump-verbose
Summary:
This patch makes some changes related to -dag-dump-verbose.
Main use case has been when debugging how SelectionDAG is
dealing with debug info (SDDbgValue nodes).
1) We now print the number of DbgValues that are mapped to each
SDNode.
2) Removed duplicated printing of DebugLoc (nowadays DebugLoc is
printed also when not using -dag-dump-verbose).
3) Renamed SDDbgValue::dump to SDDbgValue::print, and added a
new SDDbgValue::dump that will start a new line after calling
print.
4) SDDbgValue::print now prints "Order", and it also prints
some additional information when kind is CONST/FRAMEIX/VREG.
5) SelectionDAG::dump() now dumps all SDDbgValue nodes after
the list of SDNodes (both "regular" and "ByVal" SDDbgValue:s).
Invalidated nodes are not printed.
6) Prohibit inline printing of SDNode operands that has SDDbgValue
nodes associated to them.
Daniel Sanders [Fri, 18 Jan 2019 18:40:35 +0000 (18:40 +0000)]
[adt] Twine(nullptr) derefs the nullptr. Add a deleted Twine(std::nullptr_t)
Summary:
nullptr can implicitly convert to Twine as Twine(nullptr) in which case it
resolves to Twine(const char *). This constructor derefs the pointer and
therefore doesn't work. Add a Twine(std::nullptr_t) = delete to make it a
compile time error.
It turns out that in-tree usage of Twine(nullptr) is confined to a single
private method in IRBuilder where foldConstant(... const Twine &Name = nullptr)
and this method is only ever called with an explicit Name argument as making it
a mandatory argument doesn't cause compile-time or run-time errors.
Florian Hahn [Fri, 18 Jan 2019 18:37:38 +0000 (18:37 +0000)]
[SelectionDAG] Split very large token factors for chained stores to 64k chunks.
Similar to D55073. Without this change, the DAG combiner crashes on code
with more than 64k of stores in a single basic block that form parallelizable
chains.
Craig Topper [Fri, 18 Jan 2019 18:22:26 +0000 (18:22 +0000)]
[X86] Lower avx2/avx512f gather intrinsics to X86MaskedGatherSDNode instead of going directly to MachineSDNode.:
This sends these intrinsics through isel in a much more normal way. This should allow addressing mode matching in isel to make better use of the displacement field.
Florian Hahn [Fri, 18 Jan 2019 17:36:22 +0000 (17:36 +0000)]
[LCSSA] Skip blocks in sub-loops when scanning for uses.
Summary:
Scanning blocks in sub-loops for uses is unnecessary, as they were
already handled while dealing with the containing sub-loop.
This speeds up LCSSA for highly nested loops. For the test case in PR37202, it
halves the time spent in LCSSA. In cases were we won't be able to skip
any blocks, the additional lookup should be negligible.
Time-passes without this patch for test case from PR37202:
Total Execution Time: 48.5505 seconds (48.5511 wall clock)
Defer inline asm's output fixup work until after we've generated the
inline asm node itself. Remove StoresToEmit, IndirectStoresToEmit, and
RetValRegs in favor of using ConstraintOperands.