Summary:
Support for this option is needed for building Linux kernel.
This is a very frequently requested feature by kernel developers.
More details : https://lkml.org/lkml/2018/4/4/601
GCC option description for -fdelete-null-pointer-checks:
This Assume that programs cannot safely dereference null pointers,
and that no code or data element resides at address zero.
-fno-delete-null-pointer-checks is the inverse of this implying that
null pointer dereferencing is not undefined.
This feature is implemented in LLVM IR in this CL as the function attribute
"null-pointer-is-valid"="true" in IR (Under review at D47894).
The CL updates several passes that assumed null pointer dereferencing is
undefined to not optimize when the "null-pointer-is-valid"="true"
attribute is present.
Reviewers: t.p.northover, efriedma, jyknight, chandlerc, rnk, srhines, void, george.burgess.iv
Reviewed By: efriedma, george.burgess.iv
Subscribers: eraman, haicheng, george.burgess.iv, drinkcat, theraven, reames, sanjoy, xbolva00, llvm-commits
Differential Revision: https://reviews.llvm.org/D47895
llvm-svn: 336613
I don't think there's a need to use `const char *`. In most (probably all?)
cases, we need a length of a name later, so discarding a length will
lead to a wasted effort.
Differential Revision: https://reviews.llvm.org/D49046
llvm-svn: 336612
delegate method (and unit test).
The name 'replace' better captures what the old delegate method did: it
returned materialization responsibility for a set of symbols to the VSO.
The new delegate method delegates responsibility for a set of symbols to a new
MaterializationResponsibility instance. This can be used to split responsibility
between multiple threads, or multiple materialization methods.
llvm-svn: 336603
Summary:
This patch adds support for the atomicrmw instructions and the strong
cmpxchg instruction to the IRTranslator.
I've left out weak cmpxchg because LangRef.rst isn't entirely clear on what
difference it makes to the backend. As far as I can tell from the code, it
only matters to AtomicExpandPass which is run at the LLVM-IR level.
Reviewers: ab, t.p.northover, qcolombet, rovka, aditya_nandakumar, volkan, javed.absar
Reviewed By: qcolombet
Subscribers: kristof.beyls, javed.absar, igorb, llvm-commits
Differential Revision: https://reviews.llvm.org/D40092
llvm-svn: 336589
Summary:
This adds a reverse transform for the instcombine canonicalizations
that were added in D47980, D47981.
As discussed later, that was worse at least for the code size,
and potentially for the performance, too.
https://rise4fun.com/Alive/Zmpl
Reviewers: craig.topper, RKSimon, spatel
Reviewed By: spatel
Subscribers: reames, llvm-commits
Differential Revision: https://reviews.llvm.org/D48768
llvm-svn: 336585
This patch ports hasDedicatedExits, getUniqueExitBlocks and
getUniqueExitBlock in Loop to LoopBase so that they can be used
from other LoopBase sub-classes.
Reviewers: chandlerc, sanjoy, hfinkel, fhahn
Reviewed By: chandlerc
Differential Revision: https://reviews.llvm.org/D48817
llvm-svn: 336572
Summary:
This patch adds a new "integer" ValueType, and renames Number -> Double.
This allows us to preserve the full precision of int64_t when parsing integers
from the wire, or constructing from an integer.
The API is unchanged, other than giving asInteger() a clearer contract.
In addition, always output doubles with enough precision that parsing will
reconstruct the same double.
Reviewers: simon_tatham
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D46209
llvm-svn: 336541
Summary:
This consists of four main parts:
- an type json::Expr representing JSON values of dynamic kind, which can be
composed, inspected, and modified
- a JSON parser from string -> json::Expr
- a JSON printer from json::Expr -> string, with optional pretty-printing
- a convention for mapping json::Expr <=> native types (fromJSON/toJSON)
Mapping functions are provided for primitives (e.g. int, vector) and the
ObjectMapper helper helps implement fromJSON for struct/object types.
Based on clangd's usage, a couple of places I'd appreciate review attention:
- fromJSON returns only bool. A richer error-signaling mechanism may be useful
to provide useful messages, or let recursive fromJSONs (containers/structs)
do careful error recovery.
- should json::obj be always explicitly written (like json::ary)
- there's no streaming parse API. I suspect there are some simple wins like
a callback API where the document is a long array, and each element is small.
But this can probably be bolted on easily when we see the need.
Reviewers: bkramer, labath
Subscribers: mgorny, ilya-biryukov, ioeric, MaskRay, llvm-commits
Differential Revision: https://reviews.llvm.org/D45753
llvm-svn: 336534
When emitting the DWARF accelerator tables from dsymutil, we don't have
a DwarfDebug instance and we use a custom class to represent Dwarf
compile units. This patch adds an interface AccelTableWriterInfo to
abstract these from the Dwarf5AccelTableWriter, so we can have a custom
implementation for this in dsymutil.
Differential revision: https://reviews.llvm.org/D49031
llvm-svn: 336529
This allows us to handle masking in a very similar way to the default rounding version that uses llvm.fma.
I had to add new rounding mode CodeGenOnly instructions to support isel when we can't find a movss to grab the upper bits from to use the b_Int instruction.
Fast-isel tests have been updated to match new clang codegen.
We are currently having trouble folding fneg into the new intrinsic. I'm going to correct that in a follow up patch to keep the size of this one down.
A future patch will also remove the old intrinsics.
llvm-svn: 336506
Splits off isKnownNeverZeroFloat to handle +/- 0 float cases.
This will make it easier to be more aggressive with the integer isKnownNeverZero tests (similar to ValueTracking), use computeKnownBits etc.
Differential Revision: https://reviews.llvm.org/D48969
llvm-svn: 336492
The checking is done deeper inside MachineBasicBlock, but this will
hopefully help to find issues when porting the machine outliner to a
target where Liveness tracking is broken (like ARM).
Differential Revision: https://reviews.llvm.org/D49023
llvm-svn: 336481
For certain APIs, the return value of the function does not distinguish
between failure (which populates errno) and other non-error conditions
(which do not set errno).
For example, `fgets` returns `NULL` both when an error has occurred, or
upon EOF. If `errno` is already `EINTR` for whatever reason, then
```
RetryAfterSignal(nullptr, fgets, ...);
```
on a stream that has reached EOF would infinite loop.
Fix this by setting `errno` to `0` before each attempt in
`RetryAfterSignal`.
Patch by Ricky Zhou!
Differential Revision: https://reviews.llvm.org/D48755
llvm-svn: 336479
appendToVector used the wrong overload of SmallVector::append, resulting
in it appending the same element to a vector `getSize()` times. This did
not cause a problem when initially committed because appendToVector was
only used to append 1-element operands.
This changes appendToVector to use the correct overload of append().
Testing: ./unittests/IR/IRTests --gtest_filter='*DIExpressionTest*'
llvm-svn: 336466
The replaceAllDbgUsesWith utility helps passes preserve debug info when
replacing one value with another.
This improves upon the existing insertReplacementDbgValues API by:
- Updating debug intrinsics in-place, while preventing use-before-def of
the replacement value.
- Falling back to salvageDebugInfo when a replacement can't be made.
- Moving the responsibiliy for rewriting llvm.dbg.* DIExpressions into
common utility code.
Along with the API change, this teaches replaceAllDbgUsesWith how to
create DIExpressions for three basic integer and pointer conversions:
- The no-op conversion. Applies when the values have the same width, or
have bit-for-bit compatible pointer representations.
- Truncation. Applies when the new value is wider than the old one.
- Zero/sign extension. Applies when the new value is narrower than the
old one.
Testing:
- check-llvm, check-clang, a stage2 `-g -O3` build of clang,
regression/unit testing.
- This resolves a number of mis-sized dbg.value diagnostics from
Debugify.
Differential Revision: https://reviews.llvm.org/D48676
llvm-svn: 336451
The enhanced version will be used in D48893 and related patches
and an almost identical (fadd is different) version is proposed
in D28907, so adding this as a preliminary step.
llvm-svn: 336444
Previously we only iterated over functions reachable from the set of
external functions in the module. But since some of the passes under
this (notably the always-inliner and coroutine lowerer) are required for
correctness, they need to run over everything.
This just adds an extra layer of iteration over the CallGraph to keep
track of which functions we've already visited and get the next batch of
SCCs.
Should fix PR38029.
llvm-svn: 336419
The intrinsics can be implemented with a f32/f64 llvm.fma intrinsic and an insert into a zero vector.
There are a couple regressions here due to SelectionDAG not being able to pull an fneg through an extract_vector_elt. I'm not super worried about this though as InstCombine should be able to do it before we get to SelectionDAG.
llvm-svn: 336416
Summary:
Error's new operator<< is the first way to print an error without consuming it.
formatv() can now print objects with an operator<< that works with raw_ostream.
Reviewers: bkramer
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D48966
llvm-svn: 336412
This upgrades all of the intrinsics to use fneg instructions to convert fma into fmsub/fnmsub/fnmadd/fmsubadd. And uses a select instruction for masking.
This matches how clang uses the intrinsics these days.
llvm-svn: 336409
Summary: The lib paths are not correctly picked up for OpenEmbedded sysroots
(like arm-oe-linux-gnueabi). I fix this in a follow-up clang patch. But in
order to add the correct libs I need to detect if the vendor is oe. For this
reason, it is first necessary to teach llvm to detect oe vendor, which is what
this patch does.
Reviewers: chandlerc, compnerd, rengolin, javed.absar
Reviewed By: compnerd
Subscribers: kristof.beyls, dexonsmith, llvm-commits
Differential Revision: https://reviews.llvm.org/D48861
llvm-svn: 336401
writing them to a buffer and re-loading them.
Also introduces a multithreaded variant of SimpleCompiler
(MultiThreadedSimpleCompiler) for compiling IR concurrently on multiple
threads.
These changes are required to JIT IR on multiple threads correctly.
No test case yet. I will be looking at how to modify LLI / LLJIT to test
multithreaded JIT support soon.
llvm-svn: 336385
that has required alignment. This avoids issues that keep coming up with
function pointers being less aligned.
I'm pretty annoyed that we can't take advantage of function alignment
even on platforms where they *are* aligned, but build modes and other
things make taking advantage of it somewhere between hard and
impossible. The best case scenario would still embed various build modes
into the ABI causing really hard to debug issues if you compiled one
object file differently from another. =/
This should at least bring the bots back that were having trouble with
this.
llvm-svn: 336337
There's a regression in here due to inability to combine fneg inputs of X86ISD::FMSUB/FNMSUB/FNMADD nodes.
More removals to come, but I wanted to stop and fix the regression that showed up in this first.
llvm-svn: 336303
It appears that the function pointer we use there isn't reliably 4-byte
aligned. I have no idea why or how we could correct this, so for now we
just regress the Windows performance some.
Someone with access to Windows could try working on a fix. At the very
least we could use a double indirection rather than a table, but maybe
there is some way to fully restore this optimization. I don't want to
play too much with this when I don't have access to the platform and
this at least should restore the last bots.
llvm-svn: 336178
Putting `sizeof(T) <= 16` into the parameter of a `std::conditional`
causes every version of MSVC I've tried to crash:
https://godbolt.org/g/eqVULL
Really frustrating, but an extra layer of indirection through an
instantiated type gives a working way to access this computed constant.
llvm-svn: 336170
Summary:
This patch is the first in a series of patches related to the [[ http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html | RFC - A new dominator tree updater for LLVM ]].
This patch introduces the DomTreeUpdater class, which provides a cleaner API to perform updates on available dominator trees (none, only DomTree, only PostDomTree, both) using different update strategies (eagerly or lazily) to simplify the updating process.
—Prior to the patch—
- Directly calling update functions of DominatorTree updates the data structure eagerly while DeferredDominance does updates lazily.
- DeferredDominance class cannot be used when a PostDominatorTree also needs to be updated.
- Functions receiving DT/DDT need to branch a lot which is currently necessary.
- Functions using both DomTree and PostDomTree need to call the update function separately on both trees.
- People need to construct an additional DeferredDominance class to use functions only receiving DDT.
—After the patch—
Patch by Chijun Sima <simachijun@gmail.com>.
Reviewers: kuhar, brzycki, dmgreen, grosser, davide
Reviewed By: kuhar, brzycki
Author: NutshellySima
Subscribers: vsk, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D48383
llvm-svn: 336163
introducing llvm::trivially_{copy,move}_constructible type traits.
This uses a completely portable implementation of these traits provided
by Richard Smith. You can see it on compiler explorer in all its glory:
https://godbolt.org/g/QEDZjW
I have transcribed it, clang-formatted it, added some comments, and made
the tests fit into a unittest file.
I have also switched llvm::unique_function over to use these new, much
more portable traits. =D
Hopefully this will fix the build bot breakage from my prior commit.
llvm-svn: 336161
supporting move-only closures.
Most of the core optimizations for std::function are here plus
a potentially novel one that detects trivially movable and destroyable
functors and implements those with fewer indirections.
This is especially useful as we start trying to add concurrency
primitives as those often end up with move-only types (futures,
promises, etc) and wanting them to work through lambdas.
As further work, we could add better support for things like const-qualified
operator()s to support more algorithms, and r-value ref qualified operator()s
to model call-once. None of that is here though.
We can also provide our own llvm::function that has some of the optimizations
used in this class, but with copy semantics instead of move semantics.
This is motivated by increasing usage of things like executors and the task
queue where it is useful to embed move-only types like a std::promise within
a type erased function. That isn't possible without this version of a type
erased function.
Differential Revision: https://reviews.llvm.org/D48349
llvm-svn: 336156
On darwin, all virtual sections have zerofill type, and having a
.zerofill directive in a non-virtual section is not allowed. Instead of
asserting, show a nicer error.
In order to use the equivalent of .zerofill in a non-virtual section,
the usage of .zero of .space is required.
This patch replaces the assert with an error.
Differential Revision: https://reviews.llvm.org/D48517
llvm-svn: 336127
Summary:
This patch is the first in a series of patches related to the [[ http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html | RFC - A new dominator tree updater for LLVM ]].
This patch introduces the DomTreeUpdater class, which provides a cleaner API to perform updates on available dominator trees (none, only DomTree, only PostDomTree, both) using different update strategies (eagerly or lazily) to simplify the updating process.
—Prior to the patch—
- Directly calling update functions of DominatorTree updates the data structure eagerly while DeferredDominance does updates lazily.
- DeferredDominance class cannot be used when a PostDominatorTree also needs to be updated.
- Functions receiving DT/DDT need to branch a lot which is currently necessary.
- Functions using both DomTree and PostDomTree need to call the update function separately on both trees.
- People need to construct an additional DeferredDominance class to use functions only receiving DDT.
—After the patch—
Patch by Chijun Sima <simachijun@gmail.com>.
Reviewers: kuhar, brzycki, dmgreen, grosser, davide
Reviewed By: kuhar, brzycki
Subscribers: vsk, mgorny, llvm-commits
Author: NutshellySima
Differential Revision: https://reviews.llvm.org/D48383
llvm-svn: 336114
Summary:
This patch introduce new intrinsic -
strip.invariant.group that was described in the
RFC: Devirtualization v2
Reviewers: rsmith, hfinkel, nlopes, sanjoy, amharc, kuhar
Subscribers: arsenm, nhaehnle, JDevlieghere, hiraditya, xbolva00, llvm-commits
Differential Revision: https://reviews.llvm.org/D47103
Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 336073
