As discussed heavily in the original review (D70157), there's a need for the compiler to be able to selective suppress padding (either nop or prefix) to respect assumptions about the meaning of labels and instructions in generated code.
Rather than wait for syntax to be finalized - which appears to be a very slow process - this patch focuses on the compiler use case and *only* worries about the integrated assembler. To my knowledge, this covers all cases mentioned to date for clang/JIT support.
For testing purposes, I wired it up so that if the integrated assembler was using autopadding for branch alignment (e.g. enabled at command line) then the textual assembly output would contain a comment for each location where padding was enabled or disabled. This seemed like the least painful choice overall.
Note that the result of this patch effective disables the jcc errata mitigation for many constructs (statepoints, implicit null checks, xray, etc...) which is non ideal. It is at least *correct* and should allow us to enable the mitigation for the compiler. Once that's done, and a few other items are worked through, we probably want to come back to this an explore a bundling based approach instead so that we can pad instructions while keeping labels in the right place.
Differential Revision: https://reviews.llvm.org/D72303
Weak undefined symbols are preemptible after D71794.
if (sym.isPreemptible)
return false;
if (!config->isPic)
return true;
// isPic means includeInDynsym is true after D71794.
...
// We can delete this if because it can never be true.
if (sym.isUndefWeak)
return true;
Differential Revision: https://reviews.llvm.org/D71795
D59275 added the following clause to Symbol::includeInDynsym()
if (isUndefWeak() && Config->Pie && SharedFiles.empty())
return false;
D59549 explored the possibility to generalize it for -no-pie.
GNU ld's rules are architecture dependent and partly controlled by -z
{,no-}dynamic-undefined-weak. Our attempts to mimic its rules are
actually half-baked and don't provide perceivable benefits (it can save
a few more weak undefined symbols in .dynsym in a -static-pie
executable). Let's just delete the rule for simplicity. We will expect
cosmetic inconsistencies with ld.bfd in certain -static-pie scenarios.
This permits a simplification in D71795.
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D71794
Silence (clang/MSVC) static analyzer warnings that the fragment data may either write out of bounds of the local array or reference uninitialized data.
Libxml2 is already an optional dependency. It should use the same
infrastructure as the other dependencies.
Differential revision: https://reviews.llvm.org/D72290
The added testcase shows the current transformation for the operation
Z / (1.0 / Y), which remains unchanged. This will be updated to align
with the transformed code (Y * Z) with D72319.
The existing transformation Z / (X / Y) => (Y * Z) / X is not handling
this case as there are multiple uses for (1.0 / Y) in this testcase.
Patch by: @raghesh (Raghesh Aloor)
Differential Revision: https://reviews.llvm.org/D72388
This batch of intrinsics fills in all the shift instructions that take
a variable shift distance in a register, instead of an immediate. Some
of these instructions take a single shift distance in a scalar
register and apply it to all lanes; others take a vector of per-lane
distances.
These instructions are all basically one family, varying in whether
they saturate out-of-range values, and whether they round when bits
are shifted off the bottom. I've implemented them at the IR level by a
much smaller family of IR intrinsics, which take flag parameters to
indicate saturating and/or rounding (along with the usual one to
specify signed/unsigned integers).
An oddity is that all of them are //left// shift instructions – but if
you pass a negative shift count, they'll shift right. So the vector
shift distances are always vectors of //signed// integers, regardless
of whether you're considering the other input vector to be of signed
or unsigned. Also, even the simplest `vshlq` instruction in this
family (neither saturating nor rounding) has to be implemented as an
IR intrinsic, because the ordinary LLVM IR `shl` operation would
consider an out-of-range shift count to be undefined behavior.
Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard
Reviewed By: dmgreen
Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72329
This batch of intrinsics covers two sets of immediate shift
instructions, which have in common that they only overwrite part of
their output register and so they need an extra input giving its
previous value.
The VSLI and VSRI instructions shift each lane of the input vector
left or right just as if they were normal immediate VSHL/VSHR, but
then they only overwrite the output bits that correspond to actual
shifted bits of the input. So VSLI will leave the low n bits of each
output lane unchanged, and VSRI the same with the top n bits.
The V[Q][R]SHR[U]N family are all narrowing shifts: they take an input
vector of 2n-bit integers, shift each lane right by a constant, and
then narrowing the shifted result to only n bits. So they only
overwrite half of the n-bit lanes in the output register, and the B/T
suffix indicates whether it's the bottom or top half of each 2n-bit
lane.
I've implemented the whole of the latter family using a single IR
intrinsic `vshrn`, which takes a lot of i32 parameters indicating
which instruction it expands to (by specifying signedness of the input
and output types, whether it saturates and/or rounds, etc).
Reviewers: dmgreen, MarkMurrayARM, miyuki, ostannard
Reviewed By: dmgreen
Subscribers: kristof.beyls, hiraditya, cfe-commits, llvm-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D72328
Summary: Fixes fixes `readability-misleading-identation` for `if constexpr`. This is very similar to D71980.
Reviewers: alexfh
Subscribers: xazax.hun, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D72333
Summary:
This patch adds intrinsics and ISelDAG nodes for
signed and unsigned fixed-point division:
llvm.sdiv.fix.*
llvm.udiv.fix.*
These intrinsics perform scaled division on two
integers or vectors of integers. They are required
for the implementation of the Embedded-C fixed-point
arithmetic in Clang.
Patch by: ebevhan
Reviewers: bjope, leonardchan, efriedma, craig.topper
Reviewed By: craig.topper
Subscribers: Ka-Ka, ilya, hiraditya, jdoerfert, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70007
This patch moves `InPQueue` into function arguments instead of template
arguments of `releaseNode`, which is a cleaner approach.
Differential Revision: https://reviews.llvm.org/D72125
Adds a pass to the ARM backend that takes a v4i32
gather and transforms it into a call to MVE's
masked gather intrinsics.
Differential Revision: https://reviews.llvm.org/D71743
An empty string literal in an asm label does not make a whole lot of sense. GCC
does not diagnose such a construct, but it also generates code that cannot be
assembled by gas should two symbols have an empty asm label within the same TU.
This does not affect an asm statement with an empty string literal, which is
still a useful construct.
Summary:
This patch relands D71271. The problem with D71271 is that it has cyclic dependency:
CodeGen->AsmPrinter->DebugInfoDWARF->CodeGen. To avoid cyclic dependency this patch
puts implementation for DWARFOptimizer into separate library: lib/DWARFLinker.
Thus the difference between this patch and D71271 is in that DWARFOptimizer renamed into
DWARFLinker and it`s files are put into lib/DWARFLinker.
Reviewers: JDevlieghere, friss, dblaikie, aprantl
Reviewed By: JDevlieghere
Subscribers: thegameg, merge_guards_bot, probinson, mgorny, hiraditya, llvm-commits
Tags: #llvm, #debug-info
Differential Revision: https://reviews.llvm.org/D71839
Creating an ASTContext with an unknown triple is rarely a good idea (as usually
all our ASTs have a valid triple that is either from the host or the target) and the
default argument makes it far to easy to implicitly create such an AST. Let's
remove it and force people to pass a triple.
The only place where we don't pass a triple is a DWARFASTParserClangTests
where we now just pass the host triple instead (the test doesn't depend on any
triple so this shouldn't change anything).
This reverts commit a041c4ec6f.
This looks like a non-trivial change and there has been no code
reviews (at least there were no phabricator revisions attached to the
commit description). It is also causing a regression in one of our
downstream integration tests, we haven't been able to come up with a
minimal reproducer yet.
Apple's CPUs are called A7-A13 in official communication, occasionally with
weird suffixes which we probably don't need to care about. This adds each one
and describes its features. It also switches the default CPU to the canonical
name for Cyclone, but leaves legacy support in so that existing bitcode still
compiles.
ArchSpec has a superset of the information of llvm::Triple but the ClangASTContext
just uses the Triple part of it. This deletes the ArchSpec constructor and all
the code creating ArchSpecs and instead just uses the llvm::Triple constructor
for ClangASTContext.
span.cons/container.pass.cpp
N4842 22.7.3.2 [span.cons]/13 constrains span's range constructor
for ranges::contiguous_range (among other criteria).
24.4.5 [range.refinements]/2 says that contiguous_range requires data(),
and (via contiguous_range, random_access_range, bidirectional_range,
forward_range, input_range, range) it also requires begin() and end()
(see 24.4.2 [range.range]/1).
Therefore, IsAContainer needs to provide begin() and end().
(Detected by MSVC's concept-constrained implementation.)
span.cons/stdarray.pass.cpp
This test uses std::array, so it must include <array>.
<span> isn't guaranteed to drag in <array>.
(Detected by MSVC's implementation which uses a forward declaration to
avoid dragging in <array>, for increased compiler throughput.)
span.objectrep/as_bytes.pass.cpp
span.objectrep/as_writable_bytes.pass.cpp
Testing `sp.extent == std::dynamic_extent` triggers MSVC warning
C4127 "conditional expression is constant". Using `if constexpr` is a
simple way to avoid this without disrupting anyone else (as span
requires C++20 mode).
span.tuple/get.pass.cpp
22.7.3.2 [span.cons]/4.3: "Preconditions: If extent is not equal to
dynamic_extent, then count is equal to extent."
These lines were triggering undefined behavior (detected by assertions
in MSVC's implementation).
I changed the count arguments in the first two chunks, followed by
changing the span extents, in order to preserve the test's coverage
and follow the existing pattern.
span.cons/span.pass.cpp
22.7.3.2 [span.cons]/18.1 constrains span's converting constructor with
"Extent == dynamic_extent || Extent == OtherExtent is true".
This means that converting from dynamic extent to static extent is
not allowed. (Other constructors tested elsewhere, like
span(It first, size_type count), can be used to write such code.)
As this is the test for the converting constructor, I have:
* Removed the "dynamic -> static" case from checkCV(), which is
comprehensive.
* Changed the initialization of std::span<T, 0> s1{}; in
testConstexprSpan() and testRuntimeSpan(), because s1 is used below.
* Removed ASSERT_NOEXCEPT(std::span<T, 0>{s0}); from those functions,
as they are otherwise comprehensive.
* Deleted testConversionSpan() entirely. Note that this could never
compile (it had a bool return type, but forgot to say `return`). And it
couldn't have provided useful coverage, as the /18.2 constraint
"OtherElementType(*)[] is convertible to ElementType(*)[]"
permits only cv-qualifications, which are already tested by checkCV().
Summary:
Adds macro references to the dynamic index.
Tests added.
Also exposed a new API to convert path to URI in URI.h
Reviewers: hokein
Subscribers: ilya-biryukov, MaskRay, jkorous, arphaman, kadircet, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D71406
As correctly pointed out by Martin on the mailing list, Python should
only be auto-enabled if SWIG is found as well. This moves the logic of
finding SWIG into FindPythonInterpAndLibs to make that possible.
To make diagnosing easier I've included a status message to convey why
Python support is disabled.
In TestConvenienceVariables I changed %t from a file to a directory.
This tripped up mkdir which can't deal with an existing file at the
given location. In order to solve this issue on the bots I added an
`rm -rf %t` statement, but now the Windows bot complains that "This
function is not supported on this system".
If you never ran the test suite wit this temporary workaround, the test
might fail. If this happens please remove what %t expands to in the lit
output and rerun the test.
Summary:
This is analogous to D58943, which correctly finds the corresponding
fixup. However, when linker relaxations are disabled and we evaluate the
fixup, we need to also ensure we use an offset of 0 rather than the size
of the previous fragment.
Reviewers: asb, efriedma, lenary
Reviewed By: efriedma
Subscribers: hiraditya, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, MaskRay, zzheng, edward-jones, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, psnobl, benna, Jim, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71978
Summary: As a novice here I tried to `git push` my changes for a while before figuring out the correct workflow which is described on other pages. This small change doesn't reduce redundancy between those pages, but at least readers can follow the links now.
Reviewers: Kokan, Jim
Reviewed By: Kokan, Jim
Subscribers: riccibruno, kiszk, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D72077
Summary:
`__has_attribute(fallthough)` -> `__has_attribute(fallthrough)`
This is a follow-up of https://reviews.llvm.org/D72287
Reviewers: EricWF, mclow.lists, Jim
Reviewed By: Jim
Subscribers: christof, ldionne, libcxx-commits
Tags: #libc
Differential Revision: https://reviews.llvm.org/D72314
Craig Topper