This patch implements a limited form of autolinking primarily designed to allow
either the --dependent-library compiler option, or "comment lib" pragmas (
https://docs.microsoft.com/en-us/cpp/preprocessor/comment-c-cpp?view=vs-2017) in
C/C++ e.g. #pragma comment(lib, "foo"), to cause an ELF linker to automatically
add the specified library to the link when processing the input file generated
by the compiler.
Currently this extension is unique to LLVM and LLD. However, care has been taken
to design this feature so that it could be supported by other ELF linkers.
The design goals were to provide:
- A simple linking model for developers to reason about.
- The ability to to override autolinking from the linker command line.
- Source code compatibility, where possible, with "comment lib" pragmas in other
environments (MSVC in particular).
Dependent library support is implemented differently for ELF platforms than on
the other platforms. Primarily this difference is that on ELF we pass the
dependent library specifiers directly to the linker without manipulating them.
This is in contrast to other platforms where they are mapped to a specific
linker option by the compiler. This difference is a result of the greater
variety of ELF linkers and the fact that ELF linkers tend to handle libraries in
a more complicated fashion than on other platforms. This forces us to defer
handling the specifiers to the linker.
In order to achieve a level of source code compatibility with other platforms
we have restricted this feature to work with libraries that meet the following
"reasonable" requirements:
1. There are no competing defined symbols in a given set of libraries, or
if they exist, the program owner doesn't care which is linked to their
program.
2. There may be circular dependencies between libraries.
The binary representation is a mergeable string section (SHF_MERGE,
SHF_STRINGS), called .deplibs, with custom type SHT_LLVM_DEPENDENT_LIBRARIES
(0x6fff4c04). The compiler forms this section by concatenating the arguments of
the "comment lib" pragmas and --dependent-library options in the order they are
encountered. Partial (-r, -Ur) links are handled by concatenating .deplibs
sections with the normal mergeable string section rules. As an example, #pragma
comment(lib, "foo") would result in:
.section ".deplibs","MS",@llvm_dependent_libraries,1
.asciz "foo"
For LTO, equivalent information to the contents of a the .deplibs section can be
retrieved by the LLD for bitcode input files.
LLD processes the dependent library specifiers in the following way:
1. Dependent libraries which are found from the specifiers in .deplibs sections
of relocatable object files are added when the linker decides to include that
file (which could itself be in a library) in the link. Dependent libraries
behave as if they were appended to the command line after all other options. As
a consequence the set of dependent libraries are searched last to resolve
symbols.
2. It is an error if a file cannot be found for a given specifier.
3. Any command line options in effect at the end of the command line parsing apply
to the dependent libraries, e.g. --whole-archive.
4. The linker tries to add a library or relocatable object file from each of the
strings in a .deplibs section by; first, handling the string as if it was
specified on the command line; second, by looking for the string in each of the
library search paths in turn; third, by looking for a lib<string>.a or
lib<string>.so (depending on the current mode of the linker) in each of the
library search paths.
5. A new command line option --no-dependent-libraries tells LLD to ignore the
dependent libraries.
Rationale for the above points:
1. Adding the dependent libraries last makes the process simple to understand
from a developers perspective. All linkers are able to implement this scheme.
2. Error-ing for libraries that are not found seems like better behavior than
failing the link during symbol resolution.
3. It seems useful for the user to be able to apply command line options which
will affect all of the dependent libraries. There is a potential problem of
surprise for developers, who might not realize that these options would apply
to these "invisible" input files; however, despite the potential for surprise,
this is easy for developers to reason about and gives developers the control
that they may require.
4. This algorithm takes into account all of the different ways that ELF linkers
find input files. The different search methods are tried by the linker in most
obvious to least obvious order.
5. I considered adding finer grained control over which dependent libraries were
ignored (e.g. MSVC has /nodefaultlib:<library>); however, I concluded that this
is not necessary: if finer control is required developers can fall back to using
the command line directly.
RFC thread: http://lists.llvm.org/pipermail/llvm-dev/2019-March/131004.html.
Differential Revision: https://reviews.llvm.org/D60274
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360984 91177308-0d34-0410-b5e6-96231b3b80d8
R_ARM_NONE can be used to create references among sections. When
--gc-sections is used, the referenced section will be retained if the
origin section is retained.
Add a generic MCFixupKind FK_NONE as this kind of no-op relocation is
ubiquitous on ELF and COFF, and probably available on many other binary
formats. See D62014.
Reviewed By: peter.smith
Differential Revision: https://reviews.llvm.org/D61992
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360980 91177308-0d34-0410-b5e6-96231b3b80d8
getUserCost() currently returns TCC_Free for any extend of a compare (i1)
result. It seems this is only true in a limited number of cases where for
example two compares are chained. Even in those types of cases it seems
unlikely that they are generally free, while they may be in some cases.
This patch therefore removes this special handling of cast of i1. No tests
are failing because of this.
If some target want the old behavior, it could override getUserCost().
Review: Hal Finkel, Chandler Carruth, Evgeny Astigeevich, Simon Pilgrim,
Ulrich Weigand
https://reviews.llvm.org/D54742/new/
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360970 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Rather than duplicating code between PointerUnion, PointerUnion3, and
PointerUnion4 (and missing things from the latter cases, such as some of the
DenseMap support and operator==), convert PointerUnion to a variadic template
that can be used as a union of any number of pointers.
(This doesn't support PointerUnion<> right now. Adding a special case for that
would be possible, and perhaps even useful in some situations, but it doesn't
seem worthwhile until we have a concrete use case.)
Reviewers: dblaikie
Subscribers: dexonsmith, kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D62027
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360962 91177308-0d34-0410-b5e6-96231b3b80d8
SymbolStringPtr used to use nullptr as its empty value and (since it performed
ref-count operations on any non-nullptr) a pointer to a special pool-entry
instance as its tombstone.
This commit changes the scheme to use two invalid pointer values as the empty
and tombstone values, and broadens the ref-count guard to prevent ref-counting
operations from being performed on these pointers. This should improve the
performance of SymbolStringPtrs used in DenseMaps/DenseSets, as ref counting
operations will no longer be performed on the tombstone.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360925 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
the stream format is exactly the same as for ThreadList and ModuleList
streams, only the entry types are slightly different, so the changes in
this patch are just straight-forward applications of established
patterns.
Reviewers: amccarth, jhenderson, clayborg
Subscribers: markmentovai, lldb-commits, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61885
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360908 91177308-0d34-0410-b5e6-96231b3b80d8
This patch optimizes ISD::LROUND and ISD::LLROUND to fcvtas
instruction. It currently only handles the scalar version.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360894 91177308-0d34-0410-b5e6-96231b3b80d8
r360876 didn't fix 2 call sites in clang.
Expected<ArrayRef<uint8_t>> may be better but use Expected<StringRef> for now.
Follow-up of D61781.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360892 91177308-0d34-0410-b5e6-96231b3b80d8
This patch add the ISD::LROUND and ISD::LLROUND along with new
intrinsics. The changes are straightforward as for other
floating-point rounding functions, with just some adjustments
required to handle the return value being an interger.
The idea is to optimize lround/llround generation for AArch64
in a subsequent patch. Current semantic is just route it to libm
symbol.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360889 91177308-0d34-0410-b5e6-96231b3b80d8
It broke the Clang build, see llvm-commits thread.
> Expected<ArrayRef<uint8_t>> may be better but use Expected<StringRef> for now.
>
> Follow-up of D61781.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360878 91177308-0d34-0410-b5e6-96231b3b80d8
Modifies the DenseMapInfo<SymbolStringPtr>::getHashValue method to take its
argument by const-ref rather than by value (to avoid unnecessary ref-counting
operations) and to defer to DenseMapInfo<void*> for the hash value computation
(since SymbolStringPtrs are just pointers under the hood).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360831 91177308-0d34-0410-b5e6-96231b3b80d8
Before this change, they were erroneously constructed with the EH_LABEL
SDNode opcode, which caused other passes to interact with them in
incorrect ways. See the FIXME about fastisel that this addresses in the
existing test case.
Fixes PR41890
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360818 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Analogous to the other ChangeToXXX methods. See the next patch for a
use case.
Change-Id: I6548d614706834fb9109ab3c8fe915e9c6ece2a7
Reviewers: arsenm, kzhuravl
Subscribers: wdng, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61651
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360789 91177308-0d34-0410-b5e6-96231b3b80d8
The 3-field form was introduced by D3499 in 2014 and the legacy 2-field
form was planned to be removed in LLVM 4.0
For the textual format, this patch migrates the existing 2-field form to
use the 3-field form and deletes the compatibility code.
test/Verifier/global-ctors-2.ll checks we have a friendly error message.
For bitcode, lib/IR/AutoUpgrade UpgradeGlobalVariables will upgrade the
2-field form (add i8* null as the third field).
Reviewed By: rnk, dexonsmith
Differential Revision: https://reviews.llvm.org/D61547
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360742 91177308-0d34-0410-b5e6-96231b3b80d8
Port hardware assisted address sanitizer to new PM following the same guidelines as msan and tsan.
Changes:
- Separate HWAddressSanitizer into a pass class and a sanitizer class.
- Create new PM wrapper pass for the sanitizer class.
- Use the getOrINsert pattern for some module level initialization declarations.
- Also enable kernel-kwasan in new PM
- Update llvm tests and add clang test.
Differential Revision: https://reviews.llvm.org/D61709
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360707 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Currently InductionBinOps are only saved for FP induction variables, the PR extends it with non FP induction variable, so user of IVDescriptors can query the InductionBinOps for integer induction variables.
The changes in hasUnsafeAlgebra() and getUnsafeAlgebraInst() are required for the existing LIT test cases to pass. As described in the comment of the two functions, one of the requirement to return true is it is a FP induction variable. The checks was not needed because InductionBinOp was not set on non FP cases before.
https://reviews.llvm.org/D60565 depends on the patch.
Committed on behalf of @Whitney (Whitney Tsang).
Reviewers: jdoerfert, kbarton, fhahn, hfinkel, dmgreen, Meinersbur
Reviewed By: jdoerfert
Subscribers: mgorny, hiraditya, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61329
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360671 91177308-0d34-0410-b5e6-96231b3b80d8
This reinstates r360578 (git e47362c1ec1ea31b626336cc05822035601c3e57),
reverted in r360653 (git 004393681c25e34e921adccc69ae6378090dee54),
with a fix for the list added in FileCheck.rst to build without error.
Copyright:
- Linaro (changes up to diff 183612 of revision D55940)
- GraphCore (changes in later versions of revision D55940 and
in new revision created off D55940)
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar,
arichardson, rnk
Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar,
arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60385
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360665 91177308-0d34-0410-b5e6-96231b3b80d8
This adds support for the arm64_32 watchOS ABI to LLVM's low level tools,
teaching them about the specific MachO choices and constants needed to
disassemble things.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360663 91177308-0d34-0410-b5e6-96231b3b80d8
Change
std::error_code getSectionContents(DataRefImpl, StringRef &) const;
to
Expected<ArrayRef<uint8_t>> getSectionContents(DataRefImpl) const;
Many object formats use ArrayRef<uint8_t> as the underlying type, which
is generally better than StringRef to represent binary data, so change
the type to decrease the number of type conversions.
Reviewed By: ruiu, sbc100
Differential Revision: https://reviews.llvm.org/D61781
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360648 91177308-0d34-0410-b5e6-96231b3b80d8
This follows the pattern of the existing isCommutativeBinOp().
x86 shows improvements from vector narrowing for the min/max opcodes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360639 91177308-0d34-0410-b5e6-96231b3b80d8
The new fptrunc and fpext intrinsics are constrained versions of the
regular fptrunc and fpext instructions.
Reviewed by: Andrew Kaylor, Craig Topper, Cameron McInally, Conner Abbot
Approved by: Craig Topper
Differential Revision: https://reviews.llvm.org/D55897
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360581 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch is part of a patch series to add support for FileCheck
numeric expressions. This specific patch introduces regular numeric
variables which can be set on the command-line.
This commit introduces regular numeric variable that can be set on the
command-line with the -D option to a numeric value. They can then be
used in CHECK patterns in numeric expression with the same shape as
@LINE numeric expression, ie. VAR, VAR+offset or VAR-offset where offset
is an integer literal.
The commit also enable strict whitespace in the verbose.txt testcase to
check that the position or the location diagnostics. It fixes one of the
existing CHECK in the process which was not accurately testing a
location diagnostic (ie. the diagnostic was correct, not the CHECK).
Copyright:
- Linaro (changes up to diff 183612 of revision D55940)
- GraphCore (changes in later versions of revision D55940 and
in new revision created off D55940)
Reviewers: jhenderson, chandlerc, jdenny, probinson, grimar, arichardson, rnk
Subscribers: hiraditya, llvm-commits, probinson, dblaikie, grimar, arichardson, tra, rnk, kristina, hfinkel, rogfer01, JonChesterfield
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D60385
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360578 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch adds the following features defined by Arm SVE2 architecture
extension:
sve2, sve2-aes, sve2-sm4, sve2-sha3, bitperm
For existing CPUs these features are declared as unsupported to prevent
scheduler errors.
The specification can be found here:
https://developer.arm.com/docs/ddi0602/latest
Reviewers: SjoerdMeijer, sdesmalen, ostannard, rovka
Reviewed By: SjoerdMeijer, rovka
Subscribers: rovka, javed.absar, tschuett, kristof.beyls, kristina, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D61513
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360573 91177308-0d34-0410-b5e6-96231b3b80d8
Previously we had only honored alignments on individual atoms, but
tools/runtimes may assume that the section alignment is respected too.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360555 91177308-0d34-0410-b5e6-96231b3b80d8
Also updates RuntimeDyldChecker and llvm-rtdyld to support zero-fill tests by
returning a content address of zero (but no error) for zero-fill atoms, and
treating loads from zero as returning zero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360547 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
We hit undefined references building with ThinLTO when one source file
contained explicit instantiations of a template method (weak_odr) but
there were also implicit instantiations in another file (linkonce_odr),
and the latter was the prevailing copy. In this case the symbol was
marked hidden when the prevailing linkonce_odr copy was promoted to
weak_odr. It led to unsats when the resulting shared library was linked
with other code that contained a reference (expecting to be resolved due
to the explicit instantiation).
Add a CanAutoHide flag to the GV summary to allow the thin link to
identify when all copies are eligible for auto-hiding (because they were
all originally linkonce_odr global unnamed addr), and only do the
auto-hide in that case.
Most of the changes here are due to plumbing the new flag through the
bitcode and llvm assembly, and resulting test changes. I augmented the
existing auto-hide test to check for this situation.
Reviewers: pcc
Subscribers: mehdi_amini, inglorion, eraman, dexonsmith, arphaman, dang, llvm-commits, steven_wu, wmi
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D59709
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360466 91177308-0d34-0410-b5e6-96231b3b80d8
Follow up to r359122, after a bug was reported in it - the original
change too aggressively tried to move related types out of type units,
which included unnamed types (like array types) which can't reasonably
be declared-but-not-defined.
A step beyond that is that some types in type units can be anonymous, if
they are types with a name for linkage purposes (eg: "typedef struct { }
x;"). So ensure those don't get turned into plain declarations (without
signatures) because, lacking names, they can't be resolved to the
definition.
[Also include a fix for llvm-dwarfdump/libDebugInfoDWARF to pretty print
types in type units]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360458 91177308-0d34-0410-b5e6-96231b3b80d8
This fix allows the scheduler to take into account the number of instances of
each ProcResource specified. Previously a declaration in a scheduler of
ProcResource<1> would be treated identically to a declaration of
ProcResource<2>. Now the hazard recognizer would report a hazard only after all
of the resource instances are busy.
Patch by Jackson Woodruff and Momchil Velikov.
Differential Revision: https://reviews.llvm.org/D51160
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@360441 91177308-0d34-0410-b5e6-96231b3b80d8
Matt Arsenault