We have a single noret intrinsic an a lot of special handling
around it. Declare it just as any other but do not define rtn
instructions itself instead.
Differential Revision: https://reviews.llvm.org/D87719
This patch is a first draft of a new pass that adds a more flexible way
to eliminate compares based on more complex constraints collected from
dominating conditions.
In particular, it aims at simplifying conditions of the forms below
using a forward propagation approach, rather than instcomine-style
ad-hoc backwards walking of def-use chains.
if (x < y)
if (y < z)
if (x < z) <- simplify
or
if (x + 2 < y)
if (x + 1 < y) <- simplify assuming no wraps
The general approach is to collect conditions and blocks, sort them by
dominance and then iterate over the sorted list. Conditions are turned
into a linear inequality and add it to a system containing the linear
inequalities that hold on entry to the block. For blocks, we check each
compare against the system and see if it is implied by the constraints
in the system.
We also keep a stack of processed conditions and remove conditions from
the stack and the constraint system once they go out-of-scope (= do not
dominate the current block any longer).
Currently there still are the least the following areas for improvements
* Currently large unsigned constants cannot be added to the system
(coefficients must be represented as integers)
* The way constraints are managed currently is not very optimized.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D84547
Forward declare AAResults instead of the (old) AliasAnalysis type.
Remove includes from SLPVectorizer.cpp that are already included in SLPVectorizer.h.
This patch adds a isConditionImplied function that
takes a constraint and returns true if the constraint
is implied by the current constraints in the system.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D84545
This patch recommits "[ConstraintSystem] Add helpers to deal with linear constraints."
(it reverts the revert commit 8da6ae4ce1).
The reason for the revert was using __builtin_multiply_overflow, which
is not available for all compilers. The patch has been updated to use
MulOverflow from MathExtras.h
`ELFFile<ELFT>` has many methods that take pointers,
though they assume that arguments are never null and
hence could take references instead.
This patch performs such clean-up.
Differential revision: https://reviews.llvm.org/D87385
In addition to printing the individual fields, synthesize and
print the corresponding prolog for the unwind info (in reverse
order, to match how it's printed for non-packed unwind info).
Differential Revision: https://reviews.llvm.org/D87370
In the case of LTO, several DWARF units can be emitted in one section.
For an extremely large application, they may exceed the limit of 4GiB
for 32-bit offsets. As it is now possible to emit 64-bit debugging info,
the patch enables storing the larger offsets.
Differential Revision: https://reviews.llvm.org/D87026
The string pool is shared among several units in the case of LTO,
and it potentially can exceed the limit of 4GiB for an extremely
large application. As it is now possible to emit 64-bit debugging
info, the limitation can be removed.
Differential Revision: https://reviews.llvm.org/D87025
These methods are used to emit values which are 32-bit in DWARF32 and
64-bit in DWARF64. The patch fixes them so that they choose the length
automatically, depending on the DWARF format set in the Context.
Differential Revision: https://reviews.llvm.org/D87008
Add a combiner helper that replaces G_UNMERGE where all the destination lanes
are dead except the first one with a G_TRUNC.
Differential Revision: https://reviews.llvm.org/D87174
Add a combiner helper that replaces G_UNMERGE of big constants into direct
use of smaller constants.
Differential Revision: https://reviews.llvm.org/D87166
As to not conflict with the legacy PM example passes under
llvm/lib/Transforms/Hello, this is under HelloNew. This makes the
CMakeLists.txt and general directory structure less confusing for people
following the example.
Much of the doc structure was taken from WritinAnLLVMPass.rst.
This adds a HelloWorld pass which simply prints out each function name.
More will follow after this, e.g. passes over different units of IR, analyses.
https://llvm.org/docs/WritingAnLLVMPass.html contains a lot more.
Relanded with missing "Support" dependency in LLVMBuild.txt.
Reviewed By: ychen, asbirlea
Differential Revision: https://reviews.llvm.org/D86979
https://reviews.llvm.org/D87554
Patch adds one new GICombinerRule for G_FABS. The combine rule folds G_FABS(G_FABS(X)) to G_FABS(X).
Patch additionally adds new combiner tests for the AArch64 target to test this new combiner rule.
Patch by mkitzan.
Add the matching and applying function to the combiner helper for
G_UNMERGE_VALUES(G_MERGE_VALUES).
This combine also supports any merge-like input nodes, like G_BUILD_VECTORS
and is robust against bitcasts in between int unmerge and merge nodes.
When the input type of the merge node and the output type of the unmerge
node are not the same, but the sizes are, the combine still applies but
creates bitcasts between the sources and the destinations instead of
reusing the destinations directly.
Long term, the artifact combiner should probably reuse that helper, but
as of today, it doesn't use any outside helper, so I kept it this way.
Differential Revision: https://reviews.llvm.org/D87117
As to not conflict with the legacy PM example passes under
llvm/lib/Transforms/Hello, this is under HelloNew. This makes the
CMakeLists.txt and general directory structure less confusing for people
following the example.
Much of the doc structure was taken from WritinAnLLVMPass.rst.
This adds a HelloWorld pass which simply prints out each function name.
More will follow after this, e.g. passes over different units of IR, analyses.
https://llvm.org/docs/WritingAnLLVMPass.html contains a lot more.
Reviewed By: ychen, asbirlea
Differential Revision: https://reviews.llvm.org/D86979
This is consistent with the clang option added in
7ed8124d46, and the comments on the
runtime patch in D87120.
Differential Revision: https://reviews.llvm.org/D87622
This patch is the initial support for the Local Exec Thread Local
Storage model to produce code sequence and relocations correct
to the ABI for the model when using PC relative memory operations.
Patch by: Kamau Bridgeman
Differential Revision: https://reviews.llvm.org/D83404
This patch introduces the new .bb_addr_map section feature which allows us to emit the bits needed for mapping binary profiles to basic blocks into a separate section.
The format of the emitted data is represented as follows. It includes a header for every function:
| Address of the function | -> 8 bytes (pointer size)
| Number of basic blocks in this function (>0) | -> ULEB128
The header is followed by a BB record for every basic block. These records are ordered in the same order as MachineBasicBlocks are placed in the function. Each BB Info is structured as follows:
| Offset of the basic block relative to function begin | -> ULEB128
| Binary size of the basic block | -> ULEB128
| BB metadata | -> ULEB128 [ MBB.isReturn() OR MBB.hasTailCall() << 1 OR MBB.isEHPad() << 2 ]
The new feature will replace the existing "BB labels" functionality with -basic-block-sections=labels.
The .bb_addr_map section scrubs the specially-encoded BB symbols from the binary and makes it friendly to profilers and debuggers.
Furthermore, the new feature reduces the binary size overhead from 70% bloat to only 12%.
For more information and results please refer to the RFC: https://lists.llvm.org/pipermail/llvm-dev/2020-July/143512.html
Reviewed By: MaskRay, snehasish
Differential Revision: https://reviews.llvm.org/D85408
1ce82015f6 added a fix to restrict phi optimizations after phi
translations. But the current use of performedPhiTranslation only
checked whether phi translation happened for the first iterator and
missed cases where phi translations happens at subsequent
iterators/upwards defs.
This patch changes upward_defs_iteartor to take a pointer to a bool, so
we can easily ensure the final value includes all visited defs, while
still being able to conveniently use it with make_range & co.
Add a DBG_INSTR_REF instruction and a "debug instruction number" field to
MachineInstr. The two allow variable values to be specified by
identifying where the value is computed, rather than the register it lies
in, like so:
%0 = fooinst, debug-instr-number 1
[...]
DBG_INSTR_REF 1, 0
See the original RFC for motivation:
http://lists.llvm.org/pipermail/llvm-dev/2020-February/139440.html
This patch is NFCI; it only adds fields and other boiler plate.
Differential Revision: https://reviews.llvm.org/D85741
Predicates with 'let PredicateCodeUsesOperands = 1' want to examine
matched operands. When we encounter predicate code that uses operands,
analyze its named operand arguments and create a map between argument
index and name. Later, when leaf node with name is encountered, emit
GIM_RecordNamedOperand that will store that operand at its argument
index in operand list. This operand list will be an argument to c++
code of the predicate.
Differential Revision: https://reviews.llvm.org/D87285
The current organization of FileInfo and its referenced utility functions of
(GCOVFile, GCOVFunction, GCOVBlock) is messy. Some members of FileInfo are just
copied from GCOVFile. FileInfo::print (.gcov output and --intermediate output)
is interleaved with branch statistics and computation of line execution counts.
--intermediate has to do redundant .gcov output to gather branch statistics.
This patch deletes lots of code and introduces a clearer work flow:
```
fn collectFunction
for each block b
for each line lineNum
let line be LineInfo of the file on lineNum
line.exists = 1
increment function's lines & linesExec if necessary
increment line.count
line.blocks.push_back(&b)
fn collectSourceLine
compute cycle counts
count = incoming_counts + cycle_counts
if line.exists
++summary->lines
if line.count
++summary->linesExec
fn collectSource
for each line
call collectSourceLine
fn main
for each function
call collectFunction
print function summary
for each source file
call collectSource
print file summary
annotate the source file with line execution counts
if -i
print intermediate file
```
The output order of functions and files now follows the original order in
.gcno files.
Clang emits (and (ctpop X), 1) for __builtin_parity. If ctpop
isn't natively supported by the target, this leads to poor codegen
due to the expansion of ctpop being more complex than what is needed
for parity.
This adds a DAG combine to convert the pattern to ISD::PARITY
before operation legalization. Type legalization is updated
to handled Expanding and Promoting this operation. If after type
legalization, CTPOP is supported for this type, LegalizeDAG will
turn it back into CTPOP+AND. Otherwise LegalizeDAG will emit a
series of shifts and xors followed by an AND with 1.
I've avoided vectors in this patch to avoid more legalization
complexity for this patch.
X86 previously had a custom DAG combiner for this. This is now
moved to Custom lowering for the new opcode. There is a minor
regression in vector-reduce-xor-bool.ll, but a follow up patch
can easily fix that.
Fixes PR47433
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D87209
This allows the backend to tell the vectorizer to produce inloop
reductions through a TTI hook.
For the moment on ARM under MVE this means allowing integer add
reductions of the correct size. In the future this can include integer
min/max too, under -Os.
Differential Revision: https://reviews.llvm.org/D75512
NOTE: There is a mailing list discussion on this: http://lists.llvm.org/pipermail/llvm-dev/2019-December/137632.html
Complemantary to the assumption outliner prototype in D71692, this patch
shows how we could simplify the code emitted for an alignemnt
assumption. The generated code is smaller, less fragile, and it makes it
easier to recognize the additional use as a "assumption use".
As mentioned in D71692 and on the mailing list, we could adopt this
scheme, and similar schemes for other patterns, without adopting the
assumption outlining.
As discussed on llvm-dev:
http://lists.llvm.org/pipermail/llvm-dev/2020-April/140729.html
This is hopefully the final remaining showstopper before we can remove
the 'experimental' from the reduction intrinsics.
No behavior was specified for the FP min/max reductions, so we have a
mess of different interpretations.
There are a few potential options for the semantics of these max/min ops.
I think this is the simplest based on current behavior/implementation:
make the reductions inherit from the existing llvm.maxnum/minnum intrinsics.
These correspond to libm fmax/fmin, and those are similar to the (now
deprecated?) IEEE-754 maxNum/minNum functions (NaNs are treated as missing
data). So the default expansion creates calls to libm functions.
Another option would be to inherit from llvm.maximum/minimum (NaNs propagate),
but most targets just crash in codegen when given those nodes because no
default expansion was ever implemented AFAICT.
We could also just assume 'nnan' semantics by default (we are already
assuming 'nsz' semantics in the maxnum/minnum intrinsics), but some targets
(AArch64, PowerPC) support the more defined behavior, so it doesn't make much
sense to not allow a tighter spec. Fast-math-flags (nnan) can be used to
loosen the semantics.
(Note that D67507 was proposed to update the LangRef to acknowledge the more
recent IEEE-754 2019 standard, but that patch seems to have stalled. If we do
update based on the new standard, the reduction instructions can seamlessly
inherit from whatever updates are made to the max/min intrinsics.)
x86 sees a regression here on 'nnan' tests because we have underlying,
longstanding bugs in FMF creation/propagation. Those need to be fixed apart
from this change (for example: https://llvm.org/PR35538). The expansion
sequence before this patch may not have been correct.
Differential Revision: https://reviews.llvm.org/D87391
This is a followup to D86834, which partially fixed this issue in
InstSimplify. However, InstCombine repeats the same transform while
dropping poison flags -- which does not cover cases where poison is
introduced in some other way.
The fix here is a bit more comprehensive, because things are quite
entangled, and it's hard to only partially address it without
regressing optimization. There are really two changes here:
* Export the SimplifyWithOpReplaced API from InstSimplify, with an
added AllowRefinement flag. For replacements inside the TrueVal
we don't actually care whether refinement occurs or not, the
replacement is always legal. This part of the transform is now
done in InstSimplify only. (It should be noted that the current
AllowRefinement check is not sufficient -- that's an issue we
need to address separately.)
* Change the InstCombine fold to work by temporarily dropping
poison generating flags, running the fold and then restoring the
flags if it didn't work out. This will ensure that the InstCombine
fold is correct as long as the InstSimplify fold is correct.
Differential Revision: https://reviews.llvm.org/D87445
Following up on D67687.
Please refer to the RFC here http://lists.llvm.org/pipermail/llvm-dev/2020-July/143309.html
`CodeGenPassBuilder` is the NPM counterpart of `TargetPassConfig` with below differences.
- Debugging features (MIR print/verify, disable pass, start/stop-before/after, etc.) living in `TargetPassConfig` are moved to use PassInstrument as much as possible. (Implementation also lives in `TargetPassConfig.cpp`)
- `TargetPassConfig` is a polymorphic base (virtual inheritance) to build the target-dependent pipeline whereas `CodeGenPassBuilder` is the CRTP base/helper to implement the target-dependent pipeline. The motivation is flexibility for targets to customize the pipeline, inlining opportunity, and fits the overall NPM value semantics design.
- `TargetPassConfig` is a legacy immutable pass to declare hooks for targets to customize some target-independent codegen layer behavior. This is partially ported to TargetMachine::options. The rest, such as `createMachineScheduler/createPostMachineScheduler`, are left out for now. They should be implemented in LLVMTargetMachine in the future.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D83608
This patch introduces a new ConstraintSystem class, that maintains a set
of linear constraints and uses Fourier–Motzkin elimination to eliminate
constraints to check if there are solutions for the system.
It also adds a convert-constraint-log-to-z3.py script, which can parse
the debug output of the constraint system and convert it to a python
script that feeds the constraints into Z3 and checks if it produces the
same result as the LLVM implementation. This is for verification
purposes.
Reviewed By: spatel
Differential Revision: https://reviews.llvm.org/D84544
In https://reviews.llvm.org/rG257b29715bb27b7d9f6c3c40c481b6a4af0b37e5,
the definition of OptTable::Info::Flags was changed from `unsigned
short` to `unsigned int`, but the definition/declaration of
OptTable::findByPrefix wasn't updated to reflect that.
This patch updates findByPrefix accordingly.
Summary:
This is the first patch implementing the new Flang driver as outlined in [1],
[2] & [3]. It creates Flang driver (`flang-new`) and Flang frontend driver
(`flang-new -fc1`). These will be renamed as `flang` and `flang -fc1` once the
current Flang throwaway driver, `flang`, can be replaced with `flang-new`.
Currently only 2 options are supported: `-help` and `--version`.
`flang-new` is implemented in terms of libclangDriver, defaulting the driver
mode to `FlangMode` (added to libclangDriver in [4]). This ensures that the
driver runs in Flang mode regardless of the name of the binary inferred from
argv[0].
The design of the new Flang compiler and frontend drivers is inspired by it
counterparts in Clang [3]. Currently, the new Flang compiler and frontend
drivers re-use Clang libraries: clangBasic, clangDriver and clangFrontend.
To identify Flang options, this patch adds FlangOption/FC1Option enums.
Driver::printHelp is updated so that `flang-new` prints only Flang options.
The new Flang driver is disabled by default. To enable it, set
`-DBUILD_FLANG_NEW_DRIVER=ON` when configuring CMake and add clang to
`LLVM_ENABLE_PROJECTS` (e.g. -DLLVM_ENABLE_PROJECTS=“clang;flang;mlir”).
[1] “RFC: new Flang driver - next steps”
http://lists.llvm.org/pipermail/flang-dev/2020-July/000470.html
[2] “RFC: Adding a fortran mode to the clang driver for flang”
http://lists.llvm.org/pipermail/cfe-dev/2019-June/062669.html
[3] “RFC: refactoring libclangDriver/libclangFrontend to share with Flang”
http://lists.llvm.org/pipermail/cfe-dev/2020-July/066393.html
[4] https://reviews.llvm.org/rG6bf55804924d5a1d902925ad080b1a2b57c5c75c
co-authored-by: Andrzej Warzynski <andrzej.warzynski@arm.com>
Reviewed By: richard.barton.arm, sameeranjoshi
Differential Revision: https://reviews.llvm.org/D86089
Check that all passes, which report they preserve CFG,
are really preserving CFG.
A new standard instrumentation is introduced. It can be
switched on/off by the flag verify-cfg-preserved, which
is on by default for debug builds.
Reviewers: kuhar, fedor.sergeev
Differential Revision: https://reviews.llvm.org/D81558
This gives a pretty substantial size reduction; for a 6.5 MB
DLL with 300 KB .xdata, the .xdata shrinks by 66 KB.
Differential Revision: https://reviews.llvm.org/D87369
Making MaterializationResponsibility instances immovable allows their
associated VModuleKeys to be updated by the ExecutionSession while the
responsibility is still in-flight. This will be used in the upcoming
removable code feature to enable safe merging of resource keys even if
there are active compiles using the keys being merged.
Bail from maskIsAllZeroOrUndef and maskIsAllOneOrUndef prior to iterating over the number of
elements for scalable vectors.
Assert that the mask type is not scalable in possiblyDemandedEltsInMask .
Assert that the types are correct in all three functions.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D87424
This will allow non-copyable function objects (e.g. lambdas that capture
unique_ptrs) to be used with ThreadPool.
Differential Revision: https://reviews.llvm.org/D87467
This is the first in a series of patches to make implicit null checks
more general. This patch identifies instructions that preserves zero
value of a register and considers that as a valid instruction to hoist
along with the faulting load. See added testcases.
Reviewed-By: reames, dantrushin
Differential Revision: https://reviews.llvm.org/D87108
llvm::EmbedBitcodeInModule handles serializing the passed-in module, if
the provided MemoryBufferRef is invalid. This is already the path taken
in one of the uses of the API - clang::EmbedBitcode, when called from
BackendConsumer::HandleTranslationUnit - so might as well do the same
here and reduce (by very little) code duplication.
The only difference this patch introduces is that the serialization happens
with ShouldPreserveUseListOrder set to true.
Differential Revision: https://reviews.llvm.org/D87339
If there's a packed epilogue (indicated by the flag E), the EpilogueCount()
field actually should be interpreted as EpilogueOffset.
Differential Revision: https://reviews.llvm.org/D87365
This patch fixes pr45956 (https://bugs.llvm.org/show_bug.cgi?id=45956 ).
To minimize its impact to the quality of generated code, I suggest enabling
this only for LTO as a start (it has two JumpThreading passes registered).
This patch contains a flag that makes JumpThreading enable it.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D84940
This matches the changes made to handling of zlib done in 10b1b4a
where we rely on find_package and the imported target rather than
manually appending the library and include paths. The use of
LLVM_LIBXML2_ENABLED has been replaced by LLVM_ENABLE_LIBXML2
thus reducing the number of variables.
Differential Revision: https://reviews.llvm.org/D84563
We weren't using this before, so none of the MachineFunction CFG edges had the
branch probability information added. As a result, block placement later in the
pipeline was flying blind.
This is enabled only with optimizations enabled like SelectionDAG.
Differential Revision: https://reviews.llvm.org/D86824
This is a port of the functionality from SelectionDAG, which tries to find
a tree of conditions from compares that are then combined using OR or AND,
before using that result as the input to a branch. Instead of naively
lowering the code as is, this change converts that into a sequence of
conditional branches on the sub-expressions of the tree.
Like SelectionDAG, we re-use the case block codegen functionality from
the switch lowering utils, which causes us to generate some different code.
The result of which I've tried to mitigate in earlier combine patches.
Differential Revision: https://reviews.llvm.org/D86665
This combine previously tried to take sequences like:
%cond = G_ICMP pred, a, b
G_BRCOND %cond, %truebb
G_BR %falsebb
%truebb:
...
%falsebb:
...
and by inverting the compare predicate and swapping branch targets, delete the
G_BR and instead have a single conditional branch to the falsebb. Since in an
earlier patch we have a combine to fold not(icmp) into just an inverted icmp,
we don't need this combine to do as much. This patch instead generalizes the
combine by just looking for:
G_BRCOND %cond, %truebb
G_BR %falsebb
%truebb:
...
%falsebb:
...
and then inverting the condition using a not (xor). The xor can be folded away
in a separate combine. This change also lets us avoid some optimization code
in the IRTranslator.
I also think that deleting G_BRs in the combiner is unnecessary. That's
something that targets can decide to do at selection time and could simplify
generic code in future.
Differential Revision: https://reviews.llvm.org/D86664
This is the initial part of the implementation of the C++20 likelihood
attributes. It handles the attributes in an if statement.
Differential Revision: https://reviews.llvm.org/D85091
Consistently use the same pattern of returning *this from the clearUnusedBits() call to allow us to early out from the isSingleWord() path and avoid an else statement.
If a function had at most one return block, the pass would return false
regardless if an unified unreachable block was created.
This patch fixes that by refactoring runOnFunction into two separate
helper functions for handling the unreachable blocks respectively the
return blocks, as suggested by @bjope in a review comment.
This was caught using the check introduced by D80916.
Reviewed By: serge-sans-paille
Differential Revision: https://reviews.llvm.org/D85818
This patch adds isGuaranteedNotToBePoison and programUndefinedIfUndefOrPoison.
isGuaranteedNotToBePoison will be used at D75808. The latter function is used at isGuaranteedNotToBePoison.
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D84242
Some constructors of IEEEFloat do not initialize member variable exponent.
Fix it by initializing exponent with the following values:
For NaNs, the `exponent` is `maxExponent+1`.
For Infinities, the `exponent` is `maxExponent+1`.
For Zeroes, the `exponent` is `maxExponent-1`.
Patch by: @nullptr.cpp (Yang Fan)
Differential Revision: https://reviews.llvm.org/D86997
Currentl DomTreeNodeBase is using std::vectot to store it's children.
Using SmallVector should be more efficient in terms of compile-time.
A size of 4 seems to be the sweet-spot in terms of compile-time,
according to
http://llvm-compile-time-tracker.com/compare.php?from=9933188c90615c9c264ebb69117f09726e909a25&to=d7a801d027648877b20f0e00e822a7a64c58d976&stat=instructions
This results in the following geomean improvements
```
geomean insts max rss
O3 -0.31 % +0.02 %
ReleaseThinLTO -0.35 % -0.12 %
ReleaseLTO -0.28 % -0.12 %
O0 -0.06 % -0.02 %
NewPM O3 -0.36 % +0.05 %
ReleaseThinLTO (link only) -0.44 % -0.10 %
ReleaseLTO-g (link only): -0.32 % -0.03 %
```
I am not sure if there's any other benefits of using std::vector over
SmallVector.
Reviewed By: kuhar, asbirlea
Differential Revision: https://reviews.llvm.org/D87319
Current code in InstEmitter assumes all GC pointers are either
VRegs or stack slots - hence, taking only one operand.
But it is possible to have constant base, in which case it
occupies two machine operands.
Add a convinience function to StackMaps to get index of next
meta argument and use it in InsrEmitter to properly advance to
the next statepoint meta operand.
Reviewed By: reames
Differential Revision: https://reviews.llvm.org/D87252
If we have a callback, call site arguments were already associated with
the callback callee. Now we also associate the function with the
callback callee, thus we know ensure that the following holds true (if
all return nonnull):
`getAssociatedArgument()->getParent() == getAssociatedFunction()`
To test this an early exit from
`AAMemoryBehaviorCallSiteArgument::initialize``
is included as well. Without the change to getAssociatedFunction() this
kind of early exit for declarations would cause callback call site
arguments to miss out.
As we handle callback calls we need to disambiguate the call site
argument number from the callee argument number. While always equal in
non-callback calls, a callback comes with a partial parameter-argument
mapping so there is no implicit correspondence. Here we split
`IRPosition::getArgNo()` into two public functions, `getCallSiteArgNo()`
and `getCalleeArgNo()`. Usages are adjusted to pick the right one for
their purpose. This fixed some problems that would have been exposed as
we more aggressively optimize callbacks.
In `MultiSource/Benchmarks/tramp3d-v4/tramp3d-v4.cpp` we initialized
attributes until stack frame ~35k caused space to run out. The initial
size 1024 is pretty much random.
For a CFG G=(V,E), Knuth describes that by Kirchoff's circuit law, the minimum
number of counters necessary is |E|-(|V|-1). The emitted edges form a spanning
tree. libgcov emitted .gcda files leverages this optimization while clang
--coverage's doesn't.
Propagate counts by Kirchhoff's circuit law so that llvm-cov gcov can
correctly print line counts of gcc --coverage emitted files and enable
the future improvement of clang --coverage.
The TempDir.path() member function returns a StringRef. We've been
calling the data() method on that StringRef, which does not guarantee
to return a null-terminated string (required by chdir and other POSIX
functions).
Introduce the c_str() method in the TempDir class, which returns the
proper string without the need to create a copy of the path at use site.
Since a function might have portions of its code coming from multiple
different files, "start line" is ambiguous (it can't just be resolved
relative to the file/line specified). Add start file to disambiguate it.
This removes the after the fact FMF handling from D46854 in favor of passing fast math flags to getNode. This should be a superset of D87130.
This required adding a SDNodeFlags to SelectionDAG::getSetCC.
Now we manage to contant fold some stuff undefs during the
initial getNode that we don't do in later DAG combines.
Differential Revision: https://reviews.llvm.org/D87200
The get{Return,Unwind,Unreachable}Block functions in
UnifyFunctionExitNodes have not been used for many years,
so just remove them.
Reviewed By: bjope
Differential Revision: https://reviews.llvm.org/D87078
We only need to include MachineInstrBundle.h, but exposes an implicit dependency in MachineOutliner.h.
Also, remove duplicate includes from LiveRegUnits.cpp + MachineOutliner.cpp.
This patch makes the debug_ranges section optional. When we specify an
empty debug_ranges section, yaml2obj only emits the section header.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D87263
This was reverted in 503deec218
because it caused gigantic increase (3x) in branch mispredictions
in certain benchmarks on certain CPU's,
see https://reviews.llvm.org/D84108#2227365.
It has since been investigated and here are the results:
https://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20200907/827578.html
> It's an amazingly severe regression, but it's also all due to branch
> mispredicts (about 3x without this). The code layout looks ok so there's
> probably something else to deal with. I'm not sure there's anything we can
> reasonably do so we'll just have to take the hit for now and wait for
> another code reorganization to make the branch predictor a bit more happy :)
>
> Thanks for giving us some time to investigate and feel free to recommit
> whenever you'd like.
>
> -eric
So let's just reland this.
Original commit message:
I've been looking at missed vectorizations in one codebase.
One particular thing that stands out is that some of the loops
reach vectorizer in a rather mangled form, with weird PHI's,
and some of the loops aren't even in a rotated form.
After taking a more detailed look, that happened because
the loop's headers were too big by then. It is evident that
SimplifyCFG's common code hoisting transform is at fault there,
because the pattern it handles is precisely the unrotated
loop basic block structure.
Surprizingly, `SimplifyCFGOpt::HoistThenElseCodeToIf()` is enabled
by default, and is always run, unlike it's friend, common code sinking
transform, `SinkCommonCodeFromPredecessors()`, which is not enabled
by default and is only run once very late in the pipeline.
I'm proposing to harmonize this, and disable common code hoisting
until //late// in pipeline. Definition of //late// may vary,
here currently i've picked the same one as for code sinking,
but i suppose we could enable it as soon as right after
loop rotation happens.
Experimentation shows that this does indeed unsurprizingly help,
more loops got rotated, although other issues remain elsewhere.
Now, this undoubtedly seriously shakes phase ordering.
This will undoubtedly be a mixed bag in terms of both compile- and
run- time performance, codesize. Since we no longer aggressively
hoist+deduplicate common code, we don't pay the price of said hoisting
(which wasn't big). That may allow more loops to be rotated,
so we pay that price. That, in turn, that may enable all the transforms
that require canonical (rotated) loop form, including but not limited to
vectorization, so we pay that too. And in general, no deduplication means
more [duplicate] instructions going through the optimizations. But there's still
late hoisting, some of them will be caught late.
As per benchmarks i've run {F12360204}, this is mostly within the noise,
there are some small improvements, some small regressions.
One big regression i saw i fixed in rG8d487668d09fb0e4e54f36207f07c1480ffabbfd, but i'm sure
this will expose many more pre-existing missed optimizations, as usual :S
llvm-compile-time-tracker.com thoughts on this:
http://llvm-compile-time-tracker.com/compare.php?from=e40315d2b4ed1e38962a8f33ff151693ed4ada63&to=c8289c0ecbf235da9fb0e3bc052e3c0d6bff5cf9&stat=instructions
* this does regress compile-time by +0.5% geomean (unsurprizingly)
* size impact varies; for ThinLTO it's actually an improvement
The largest fallout appears to be in GVN's load partial redundancy
elimination, it spends *much* more time in
`MemoryDependenceResults::getNonLocalPointerDependency()`.
Non-local `MemoryDependenceResults` is widely-known to be, uh, costly.
There does not appear to be a proper solution to this issue,
other than silencing the compile-time performance regression
by tuning cut-off thresholds in `MemoryDependenceResults`,
at the cost of potentially regressing run-time performance.
D84609 attempts to move in that direction, but the path is unclear
and is going to take some time.
If we look at stats before/after diffs, some excerpts:
* RawSpeed (the target) {F12360200}
* -14 (-73.68%) loops not rotated due to the header size (yay)
* -272 (-0.67%) `"Number of live out of a loop variables"` - good for vectorizer
* -3937 (-64.19%) common instructions hoisted
* +561 (+0.06%) x86 asm instructions
* -2 basic blocks
* +2418 (+0.11%) IR instructions
* vanilla test-suite + RawSpeed + darktable {F12360201}
* -36396 (-65.29%) common instructions hoisted
* +1676 (+0.02%) x86 asm instructions
* +662 (+0.06%) basic blocks
* +4395 (+0.04%) IR instructions
It is likely to be sub-optimal for when optimizing for code size,
so one might want to change tune pipeline by enabling sinking/hoisting
when optimizing for size.
Reviewed By: mkazantsev
Differential Revision: https://reviews.llvm.org/D84108
This reverts commit 503deec218.
To enable the cost of constants, the helper function has been
reorganised:
- A struct has been introduced to hold SCEV operand information so
that we know the user of the operand, as well as the operand index.
The Worklist now uses instead instead of a bare SCEV.
- The costing of each SCEV, and collection of its operands, is now
performed in a helper function.
Differential Revision: https://reviews.llvm.org/D86050
Modify FoldBranchToCommonDest to consider the cost of inserting
instructions when attempting to combine predicates to fold blocks.
The threshold can be controlled via a new option:
-simplifycfg-branch-fold-threshold which defaults to '2' to allow
the insertion of a not and another logical operator.
Differential Revision: https://reviews.llvm.org/D86526
This patch makes the debug_addr section optional. When an empty
debug_addr section is specified, yaml2obj only emits a section header
for it.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D87205
This is the split part of D86269, which add a new ELF machine flag called EM_CSKY and related relocations.
Some target-specific flags and tests for csky can be added in follow-up patches later.
Differential Revision: https://reviews.llvm.org/D86610
This patch implements the vec_expandm function prototypes in altivec.h in order
to utilize the vector expand with mask instructions introduced in Power10.
Differential Revision: https://reviews.llvm.org/D82727
Previously SDNodeFlags::instersectWith(Flags) would do nothing if Flags was
in an undefined state, which is very bad given that this is the default when
getNode() is called without passing an explicit SDNodeFlags argument.
This meant that if an already existing and reused node had a flag which the
second caller to getNode() did not set, that flag would remain uncleared.
This was exposed by https://bugs.llvm.org/show_bug.cgi?id=47092, where an NSW
flag was incorrectly set on an add instruction (which did in fact overflow in
one of the two original contexts), so when SystemZElimCompare removed the
compare with 0 trusting that flag, wrong-code resulted.
There is more that needs to be done in this area as discussed here:
Differential Revision: https://reviews.llvm.org/D86871
Review: Ulrich Weigand, Sanjay Patel
TPCDynamicLibrarySearchGenerator was generating errors on missing
symbols, but that doesn't fit the DefinitionGenerator contract: A symbol
that isn't generated by a particular generator should not cause an
error.
This commit fixes the error by using SymbolLookupFlags::WeaklyReferencedSymbol
for all elements of the lookup, and switches llvm-jitlink to use
TPCDynamicLibrarySearchGenerator.
Reduce to forward declaration, add the Register.h include that we still needed, move CCState::ensureMaxAlignment into CallingConvLower.cpp as it was the only function that needed the full definition of MachineFunction.
Fix a few implicit dependencies further down.
I have fixed up some more ElementCount/TypeSize related warnings in
the following tests:
CodeGen/AArch64/sve-split-extract-elt.ll
CodeGen/AArch64/sve-split-insert-elt.ll
In SelectionDAG::CreateStackTemporary we were relying upon the implicit
cast from TypeSize -> uint64_t when calling MachineFrameInfo::CreateStackObject.
I've fixed this by passing in the known minimum size instead, which I
believe is fine because the associated stack id indicates whether this
is a scalable object or not.
I've also fixed up a case in TargetLowering::SimplifyDemandedBits when
extracting a vector element from a scalable vector. The result is a scalar,
hence it wasn't caught at the start of the function. If the vector is
scalable we just bail out for now.
Differential Revision: https://reviews.llvm.org/D86431
This patch updates MemCpyOpt to preserve MemorySSA. It uses the
MemoryDef at the insertion point of the builder and inserts the new def
after that def.
In some cases, we just modify a memory instruction. In that case, get
the defining access, then remove the memory access and add a new one.
If the defining access is in a different block, insert a new def at the
beginning of the current block, otherwise after the defining access.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D86651
- When an operand is changed into an immediate value or like, ensure their
target flags being cleared or set properly.
Differential Revision: https://reviews.llvm.org/D87109
This hashing scheme has been useful out of tree, and I want to start
experimenting with it. Specifically I want to experiment on the
MIRVRegNamer, MIRCanononicalizer, and eventually the MachineOutliner.
This diff is a first step, that optionally brings stable hashing to the
MIRVRegNamer (and as a result, the MIRCanonicalizer). We've tested this
hashing scheme on a lot of MachineOperand types that llvm::hash_value
can not handle in a stable manner.
This stable hashing was also the basis for
"Global Machine Outliner for ThinLTO" in EuroLLVM 2020
http://llvm.org/devmtg/2020-04/talks.html#TechTalk_58
Credits: Kyungwoo Lee, Nikolai Tillmann
Differential Revision: https://reviews.llvm.org/D86952
This also changes -lint from an analysis to a pass. It's similar to
-verify, and that is a normal pass, and lives in llvm/IR.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D87057
Although LLVM supports vectorization of loops containing log2, it did not support using SVML implementation of it. Added support so that when clang is invoked with -fveclib=SVML now an appropriate SVML library log2 implementation will be invoked.
Follow up on: https://reviews.llvm.org/D77114
Tests:
Added unit tests to svml-calls.ll, svml-calls-finite.ll. Can be run with llvm-lint.
Created a simple c++ file that tests log2, and used clang+ to build it, and output final assembly.
Reviewed By: wenlei, craig.topper
Differential Revision: https://reviews.llvm.org/D86730
Use forward declarations and move the include down to dependent files that actually use it.
This also exposes a number of implicit dependencies on KnownBits.h
Since the parameter is not used anywhere, and the default size of 16
apparently causes PR47359, remove it. This ensures that IntervalMap will
automatically determine the optimal size, using its NodeSizer struct.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D87044
A new hidden option -print-changed is added along with code to support
printing the IR as it passes through the opt pipeline in the new pass
manager. Only those passes that change the IR are reported, with others
only having the banner reported, indicating that they did not change the
IR, were filtered out or ignored. Filtering of output via the
-filter-print-funcs is supported and a new supporting hidden option
-filter-passes is added. The latter takes a comma separated list of pass
names and filters the output to only show those passes in the list that
change the IR. The output can also be modified via the -print-module-scope
function.
The code introduces a template base class that generalizes the comparison
of IRs that takes an IR representation as template parameter. The
constructor takes a series of lambdas that provide an event based API
for generalized reporting of IRs as they are changed in the opt pipeline
through the new pass manager.
The first of several instantiations is provided that prints the IR
in a form similar to that produced by -print-after-all with the above
mentioned filtering capabilities. This version, and the others to
follow will be introduced at the upcoming developer's conference.
See https://hotcrp.llvm.org/usllvm2020/paper/29 for more information.
Reviewed By: yrouban (Yevgeny Rouban)
Differential Revision: https://reviews.llvm.org/D86360
Preserve MemorySSA if it is available before running GVN.
DSE with MemorySSA will run closely after GVN. If GVN and 2 other
passes preserve MemorySSA, DSE can re-use MemorySSA used by LICM
when doing LTO.
Reviewed By: asbirlea
Differential Revision: https://reviews.llvm.org/D86534
Add support in llvm-readobj for displaying them and support in the
asm parsser, AArch64TargetStreamer and MCWin64EH for emitting them.
The directives for the remaining basic opcodes have names that
match the opcode in the documentation.
The directives for custom stack cases, that are named
MSFT_OP_TRAP_FRAME, MSFT_OP_MACHINE_FRAME, MSFT_OP_CONTEXT
and MSFT_OP_CLEAR_UNWOUND_TO_CALL, are given matching assembler
directive names that fit into the rest of the opcode naming;
.seh_trap_frame, .seh_context, .seh_clear_unwound_to_call
The opcode MSFT_OP_MACHINE_FRAME is mapped to the existing
opecode enum UOP_PushMachFrame that is used on x86_64, and also
uses the corresponding existing x86_64 directive name
.seh_pushframe.
Differential Revision: https://reviews.llvm.org/D86889
Commit 3a29393b47 removes the cmath/math.h
includes from the DataTypes.h header to speed up parsing. However the
DataTypes.h header was using this header to get the macro `HUGE_VAL` for its own
`HUGE_VALF` macro definition. Now the macro instead just expands into a plain
`HUGE_VAL` token which leads to compiler errors unless `math.h` was previously
included by the including source file. It also leads to compiler warnings with
enabled module builds which point out this inconsistency.
The correct way to fix this seems to be to just remove HUGE_VALF from the
header. llvm-c is not referencing that macro from what I can see and users
probably should just include the math headers if they need it (or define it on
their own for really old C versions).
Reviewed By: JDevlieghere
Differential Revision: https://reviews.llvm.org/D83761
Add a reproducer verifier that catches:
- Missing or invalid home directory
- Missing or invalid working directory
- Missing or invalid module/symbol paths
- Missing files from the VFS
The verifier is enabled by default during replay, but can be skipped by
passing --reproducer-no-verify.
Differential revision: https://reviews.llvm.org/D86497
This also changes -lint from an analysis to a pass. It's similar to
-verify, and that is a normal pass, and lives in llvm/IR.
Reviewed By: ychen
Differential Revision: https://reviews.llvm.org/D87057
This helps SelectionDAGBuilder recognize the splat can be used as a uniform base.
Reviewed By: RKSimon
Differential Revision: https://reviews.llvm.org/D86371
This patch changes errors in `SmallVector::grow` that are independent of
memory capacity to be reported using report_fatal_error or
std::length_error instead of report_bad_alloc_error, which falsely signals
an OOM.
It also cleans up a few related things:
- makes report_bad_alloc_error to print the failure reason passed
to it.
- fixes the documentation to indicate that report_bad_alloc_error
calls `abort()` not "an assertion"
- uses a consistent name for the size/capacity argument to `grow`
and `grow_pod`
Reviewed By: mehdi_amini, MaskRay
Differential Revision: https://reviews.llvm.org/D86892
This patch implements the builtins for Vector Multiply Builtins (vmulxxd family of instructions), and adds the appropriate test cases for these builtins. The builtins utilize the vector multiply instructions itnroduced with ISA 3.1.
Differential Revision: https://reviews.llvm.org/D83955
When lowering fixed length vector operations for SVE the subvector
operations are used extensively to marshall data between scalable
and fixed-length vectors. This means that sequences like:
extract_subvec(binop(insert_subvec(a), insert_subvec(b)))
are very common. DAGCombine only checks if the resulting binop is
legal or can be custom lowered when undoing such sequences. When
it's custom lowering that is introducing them the result is an
infinite legalise->combine->legalise loop.
This patch extends the isOperationLegalOr... functions to include
a "LegalOnly" parameter to restrict the check to legal operations
only. Although isOperationLegal could be used it's common for
the affected code paths to be visited pre and post legalisation,
so the extra parameter keeps the code tidy.
Differential Revision: https://reviews.llvm.org/D86450
Unwinders may only preserve the lower 64bits of Neon and SVE registers,
as only the registers in the base ABI are guaranteed to be preserved
over the exception edge. The caller will need to preserve additional
registers for when the call throws an exception and the unwinder has
tried to recover state.
For e.g.
svint32_t bar(svint32_t);
svint32_t foo(svint32_t x, bool *err) {
try { bar(x); } catch (...) { *err = true; }
return x;
}
`z0` needs to be spilled before the call to `bar(x)` and reloaded before
returning from foo, as the exception handler may have clobbered z0.
Reviewed By: efriedma
Differential Revision: https://reviews.llvm.org/D84737
Before upstream a new target called CSKY, make a new triple of that called Triple::csky.
For now, it's a 32-bit little endian target and the detail can be referred at D86269.
This is the split part of D86269, which add a new target called CSKY.
Differential Revision: https://reviews.llvm.org/D86505
Summary:
Analyses are preserved in MemCpyOptimizer.
Get analyses before running the pass and store the pointers, instead of
using lambdas and getting them every time on demand.
Reviewers: lenary, deadalnix, mehdi_amini, nikic, efriedma
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D74494
Some LLVM unit tests forget to clean up temporary files and
directories. Introduce RAII classes for cleaning them up.
Refactor the tests to use those classes.
Differential Revision: https://reviews.llvm.org/D83228
Volkan Keles