The COFF specific `DataReferencedByCode` complexity (D103372 D103717) is due to
a link.exe limitation: an external symbol in IMAGE_COMDAT_SELECT_ASSOCIATIVE is
not really dropped, so it can cause duplicate definition error.
Clang patch D106614 added attribute btf_tag support. This patch
generates btf_tag annotations for DIComposite types.
A field "annotations" is introduced to DIComposite, and the
annotations are represented as an DINodeArray, similar to
DIComposite elements. The following example illustrates
how annotations are encoded in IR:
distinct !DICompositeType(..., annotations: !10)
!10 = !{!11, !12}
!11 = !{!"btf_tag", !"a"}
!12 = !{!"btf_tag", !"b"}
Each btf_tag annotation is represented as a 2D array of
meta strings. Each record may have more than one
btf_tag annotations, as in the above example.
Differential Revision: https://reviews.llvm.org/D106615
This patch adds vector-predicated ("VP") reduction intrinsics corresponding to
each of the existing unpredicated `llvm.vector.reduce.*` versions. Unlike the
unpredicated reductions, all VP reductions have a start value. This start value
is returned when the no vector element is active.
Support for expansion on targets without native vector-predication support is
included.
This patch is based on the ["reduction
slice"](https://reviews.llvm.org/D57504#1732277) of the LLVM-VP reference patch
(https://reviews.llvm.org/D57504).
Reviewed By: craig.topper
Differential Revision: https://reviews.llvm.org/D104308
SwitchInst should have a void result type.
Add a check to the verifier to catch this error.
Reviewed By: samparker
Differential Revision: https://reviews.llvm.org/D108084
This patch updates ConstantVector::getSplat to use poison instead
of undef when using insertelement/shufflevector to splat.
This follows on from D93793.
Differential Revision: https://reviews.llvm.org/D107751
When LLVM is used in other projects, it may happen that global cons-
tructors will execute before the call to ParseCommandLineOptions.
Since OptBisect is initialized via a constructor, and has no ability
to be updated at a later time, passing "-opt-bisect-limit" to the
parse function may have no effect.
To avoid this problem use a cl::cb (callback) to set the bisection
limit when the option is actually processed.
Differential Revision: https://reviews.llvm.org/D104551
It's entirely possible (because it actually happened) for a bool
variable to end up with a 256-bit DW_AT_const_value. This came about
when a local bool variable was initialized from a bitfield in a
32-byte struct of bitfields, and after inlining and constant
propagation, the variable did have a constant value. The sequence of
optimizations had it carrying "i256" values around, but once the
constant made it into the llvm.dbg.value, no further IR changes could
affect it.
Technically the llvm.dbg.value did have a DIExpression to reduce it
back down to 8 bits, but the compiler is in no way ready to emit an
oversized constant *and* a DWARF expression to manipulate it.
Depending on the circumstances, we had either just the very fat bool
value, or an expression with no starting value.
The sequence of optimizations that led to this state did seem pretty
reasonable, so the solution I came up with was to invent a DWARF
constant expression folder. Currently it only does convert ops, but
there's no reason it couldn't do other ops if that became useful.
This broke three tests that depended on having convert ops survive
into the DWARF, so I added an operator that would abort the folder to
each of those tests.
Differential Revision: https://reviews.llvm.org/D106915
Constant::getSplatValue has O(N) time complexity in the worst case,
where N is the # of elements in a vector. So we call
Constant::getAggregateElement first and return earlier if possible to
avoid unnecessary getSplatValue calls.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D107252
This patch adds an initial ShuffleVectorInst::isInsertSubvectorMask helper to recognize 2-op shuffles where the lowest elements of one of the sources are being inserted into the "in-place" other operand, this includes "concat_vectors" patterns as can be seen in the Arm shuffle cost changes. This also helped fix a x86 issue with irregular/length-changing SK_InsertSubvector costs - I'm hoping this will help with D107188
This doesn't currently attempt to work with 1-op shuffles that could either be a "widening" shuffle or a self-insertion.
The self-insertion case is tricky, but we currently always match this with the existing SK_PermuteSingleSrc logic.
The widening case will be addressed in a follow up patch that treats the cost as 0.
Masks with a high number of undef elts will still struggle to match optimal subvector widths - its currently bounded by minimum-width possible insertion, whilst some cases would benefit from wider (pow2?) subvectors.
Differential Revision: https://reviews.llvm.org/D107228
We might want to use info from GC strategy in middle end analysis.
The motivation for this is provided in D99135: we may want to ask
a GC if it's going to work with a given pointer (currently this code
makes naive check by the method name).
Differetial Revision: https://reviews.llvm.org/D100559
Reviewed By: reames
Currently, the default alignment is much larger than the actual size of
the vector in memory. Fix this to use a sane default.
For SVE, temporarily remove lowering of load/store operations for
predicates with less than 16 elements. The layout the backend was
assuming for SVE predicates with less than 16 elements doesn't agree
with the frontend. More work probably needs to be done here.
This change is, strictly speaking, not backwards-compatible at the
bitcode level. But probably nobody is actually depending on that; i1
vectors in memory are rare, and the code that does use them probably
ends up forcing the alignment to something sane anyway. If we think
this is a concern, I can restrict this to scalable vectors for now
(where it's actually causing issues for me at the moment).
Differential Revision: https://reviews.llvm.org/D88994
Target-dependent constant folding will fold these down to simple
constants (or at least, expressions that don't involve a GEP). We don't
need heroics to try to optimize the form of the expression before that
happens.
Fixes https://bugs.llvm.org/show_bug.cgi?id=51232 .
Differential Revision: https://reviews.llvm.org/D107116
This is a second attempt to fix the EXPENSIVE_CHECKS issue that was mentioned In D91661#2875179 by @jroelofs.
(The first attempt was in D105983)
D91661 more or less completely reverted D49126 and by doing so also removed the cleanup logic of the created declarations and calls.
This patch is a replacement for D91661 (which must itself be reverted first). It replaces the custom declaration creation with the
generic version and shows the test impact. It also tracks the number of NamedValues to detect if a new prototype was added instead
of looking at the available users of a prototype.
Reviewed By: jroelofs
Differential Revision: https://reviews.llvm.org/D106147
When hoisting/moving calls to locations, we strip unknown metadata. Such calls are usually marked `speculatable`, i.e. they are guaranteed to not cause undefined behaviour when run anywhere. So, we should strip attributes that can cause immediate undefined behaviour if those attributes are not valid in the context where the call is moved to.
This patch introduces such an API and uses it in relevant passes. See
updated tests.
Fix for PR50744.
Reviewed By: nikic, jdoerfert, lebedev.ri
Differential Revision: https://reviews.llvm.org/D104641
This fixes an assert firing when compiling code which involves 128 bit
integrals.
This would trigger runtime checks similar to this:
```
Assertion failed: getMinSignedBits() <= 64 && "Too many bits for int64_t", file llvm/include/llvm/ADT/APInt.h, line 1646
```
To get around this, we just saturate those big values.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D105320
DIEnumerator stores an APInt as of April 2020, so now we don't need to
truncate the enumerator value to 64 bits. Fixes assertions during IRGen.
Split from D105320, thanks to Matheus Izvekov for the test case and
report.
Differential Revision: https://reviews.llvm.org/D106585
Proposed alternative to D105338.
This is ugly, but short-term I think it's the best way forward: first,
let's formalize the hacks into a coherent model. Then we can consider
extensions of that model (we could have different flavors of volatile
with different rules).
Differential Revision: https://reviews.llvm.org/D106309
This adjusts mayHaveSideEffect() to return true for !willReturn()
instructions. Just like other side-effects, non-willreturn calls
(aka "divergence") cannot be removed and cannot be reordered relative
to other side effects. This fixes a number of bugs where
non-willreturn calls are either incorrectly dropped or moved. In
particular, it also fixes the last open problem in
https://bugs.llvm.org/show_bug.cgi?id=50511.
I performed a cursory review of all current mayHaveSideEffect()
uses, which convinced me that these are indeed the desired default
semantics. Places that do not want to consider non-willreturn as a
sideeffect generally do not want mayHaveSideEffect() semantics at
all. I identified two such cases, which are addressed by D106591
and D106742. Finally, there is a use in SCEV for which we don't
really have an appropriate API right now -- what it wants is
basically "would this be considered forward progress". I've just
spelled out the previous semantics there.
Differential Revision: https://reviews.llvm.org/D106749
Rather than adding methods for dropping these attributes in
various places, add a function that returns an AttrBuilder with
these attributes, which can then be used with existing methods
for dropping attributes. This is with an eye on D104641, which
also needs to drop them from returns, not just parameters.
Also be more explicit about the semantics of the method in the
documentation. Refer to UB rather than Undef, which is what this
is actually about.
From LangRef:
> if the parameter or return pointer is null, poison value is
> returned or passed instead. The nonnull attribute should be
> combined with the noundef attribute to ensure a pointer is not
> null or otherwise the behavior is undefined.
Dropping noundef is sufficient to prevent UB. Including nonnull
in this method just muddies the semantics.
This was previously combining indices even though they operate on
different types. For non-opaque pointers, the condition is
automatically satisfied based on the pointer types being equal.
This is part of a patch series working towards the ability to make
SourceLocation into a 64-bit type to handle larger translation units.
!srcloc is generated in clang codegen, and pulled back out by llvm
functions like AsmPrinter::emitInlineAsm that need to report errors in
the inline asm. From there it goes to LLVMContext::emitError, is
stored in DiagnosticInfoInlineAsm, and ends up back in clang, at
BackendConsumer::InlineAsmDiagHandler(), which reconstitutes a true
clang::SourceLocation from the integer cookie.
Throughout this code path, it's now 64-bit rather than 32, which means
that if SourceLocation is expanded to a 64-bit type, this error report
won't lose half of the data.
The compiler will tolerate both of i32 and i64 !srcloc metadata in
input IR without faulting. Test added in llvm/MC. (The semantic
accuracy of the metadata is another matter, but I don't know of any
situation where that matters: if you're reading an IR file written by
a previous run of clang, you don't have the SourceManager that can
relate those source locations back to the original source files.)
Original version of the patch by Mikhail Maltsev.
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D105491
Remove the assert in AssemblyWriter::printBasicBlock() and
in BasicBlock::isEntryBlock() that require blocks to have parents.
Instead, have BasicBlock::isEntryBlock() return false for unattached
blocks. This allows us to call these functions for blocks that are
not yet added to a module which is a useful debugging capability.
Committing for xiaoqing_wu
https://reviews.llvm.org/D106127k
In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are retained, and
they happen to define strong external symbols with the same names,
there will be a duplicate definition linker error.
In PE/COFF, the selection kind lowers to `IMAGE_COMDAT_SELECT_NODUPLICATES`.
The name describes the corollary instead of the immediate semantics. The name
can cause confusion to other binary formats (ELF, wasm) which have implemented/
want to implement the "no deduplication" selection kind. Rename it to be clearer.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D106319
For musttail calls, ABI attributes between the function and the
musttail call must match. The current check discards the type of
type attributes like byval, which means that it will consider
byval(i32) and byval(i64) (or similar) as compatible.
I assume this is a leftover from before these attributes had a
type argument. Ran into this while trying to tighten an assertion
in AttrBuilder.
Differential Revision: https://reviews.llvm.org/D105841
Use the elementtype attribute introduced in D105407 for the
llvm.preserve.array/struct.index intrinsics. It carries the
element type of the GEP these intrinsics effectively encode.
This patch:
* Adds a verifier check that the attribute is required.
* Adds it in the IRBuilder methods for these intrinsics.
* Autoupgrades old bitcode without the attribute.
* Updates the lowering code to use the attribute rather than
the pointer element type.
* Updates lots of tests to specify the attribute.
* Adds -force-opaque-pointers to the intrinsic-array.ll test
to demonstrate they work now.
https://reviews.llvm.org/D106184
As suggested on D105733, this adds a verifier rule that calls to
intrinsics must match the signature of the intrinsic.
Without opaque pointers this is automatically enforced for all
calls, because the pointer types need to match. If the signatures
don't match, a pointer bitcast has to be inserted. For intrinsics
in particular, such bitcasts are not legal, because the address of
intrinsics cannot be taken.
With opaque pointers, there are no more pointer bitcasts, so it's
generally possible for the call and the callee signature to differ.
However, for intrinsics we still want to enforce that the signatures
must match, the same as was done before through the address taken
check.
We can't enforce this more generally for non-intrinsics, because
calls with mismatched signatures at the very least can legally
occur in unreachable code, and might also be valid in some other
cases, depending on how exactly the signatures differ.
Differential Revision: https://reviews.llvm.org/D106013
Intrinsics can only be called directly, taking their address is not
legal. This is currently only enforced for intrinsics that have an
ID, rather than all intrinsics. Adjust the check to cover all
intrinsics.
This came up in D106013.
Differential Revision: https://reviews.llvm.org/D106095
This implements the elementtype attribute specified in D105407. It
just adds the attribute and the specified verifier rules, but
doesn't yet make use of it anywhere.
Differential Revision: https://reviews.llvm.org/D106008
With the current deref semantics, this is redundant - since we assume that anything which is dereferenceable (ever) can't be freed - but it becomes neccessary for the deref-at-point semantics.
Testing wise, this is covered by test/CodeGen/X86/hoist-invariant-load.ll when -use-dereferenceable-at-point-semantics is active. I didn't bother duplicating the command line since a) it's an in-development mode, and b) the change is pretty obvious.
Fangrui Song