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
This is mostly an NFC patch because the involved methods are used when
emitting DWO files, which is incompatible with DWARFv3, or for platforms
where DWARF64 is not supported yet.
Differential Revision: https://reviews.llvm.org/D87015
The patch also adds a method to choose an appropriate DWARF form
to represent section offsets according to the version and the format
of producing debug info.
Differential Revision: https://reviews.llvm.org/D87014
DW_FORM_sec_offset and DW_FORM_strp imply values of different sizes with
DWARF32 and DWARF64. The patch fixes DIE value classes to use correct
sizes when emitting their values. For DIELocList it ensures that the
requested DWARF form matches the current DWARF format because that class
uses a method that selects the size automatically.
Differential Revision: https://reviews.llvm.org/D87009
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
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.
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
Halide users reported this here: https://llvm.org/pr46176
I reported the issue to MSVC here:
https://developercommunity.visualstudio.com/content/problem/1179643/msvc-copies-overaligned-non-trivially-copyable-par.html
This codepath is apparently not covered by LLVM's unit tests, so I added
coverage in a unit test.
If we want to support this configuration going forward, it means that is
in general not safe to pass a SmallVector<T, N> by value if alignof(T)
is greater than 4. This doesn't appear to come up often because passing
a SmallVector by value is inefficient and not idiomatic: it copies the
inline storage. In this case, the SmallVector<LLT,4> is captured by
value by a lambda, and the lambda is passed by value into std::function,
and that's how we hit the bug.
Differential Revision: https://reviews.llvm.org/D87475
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.
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 implements support for isKnownNonZero, computeKnownBits when freeze is involved.
```
br (x != 0), BB1, BB2
BB1:
y = freeze x
```
In the above program, we can say that y is non-zero. The reason is as follows:
(1) If x was poison, `br (x != 0)` raised UB
(2) If x was fully undef, the branch again raised UB
(3) If x was non-zero partially undef, say `undef | 1`, `freeze x` will return a nondeterministic value which is also non-zero.
(4) If x was just a concrete value, it is trivial
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D75808
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
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.
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
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
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
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
This patch adds an initial, incomeplete and unsound implementation of
canReplacePointersIfEqual to check if a pointer value A can be replaced
by another pointer value B, that are deemed to be equivalent through
some means (e.g. information from conditions).
Note that is in general not sound to blindly replace pointers based on
equality, for example if they are based on different underlying objects.
LLVM's memory model is not completely settled as of now; see
https://bugs.llvm.org/show_bug.cgi?id=34548 for a more detailed
discussion.
The initial version of canReplacePointersIfEqual only rejects a very
specific case: replacing a pointer with a constant expression that is
not dereferenceable. Such a replacement is problematic and can be
restricted relatively easily without impacting most code. Using it to
limit replacements in GVN/SCCP/CVP only results in small differences in
7 programs out of MultiSource/SPEC2000/SPEC2006 on X86 with -O3 -flto.
This patch is supposed to be an initial step to improve the current
situation and the helper should be made stricter in the future. But this
will require careful analysis of the impact on performance.
Reviewed By: aqjune
Differential Revision: https://reviews.llvm.org/D85524
This relands e9a3d1a401 which was originally
missing linking LLVMSupport into LLMVFileCheck which broke the SHARED_LIBS build.
Original summary:
The actual FileCheck logic seems to be implemented in LLVMSupport. I don't see a
good reason for having FileCheck implemented there as it has a very specific use
while LLVMSupport is a dependency of pretty much every LLVM tool there is. In
fact, the only use of FileCheck I could find (outside the FileCheck tool and the
FileCheck unit test) is a single call in GISelMITest.h.
This moves the FileCheck logic to its own LLVMFileCheck library. This way only
FileCheck and the GlobalISelTests now have a dependency on this code.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D86344
The actual FileCheck logic seems to be implemented in LLVMSupport. I don't see a
good reason for having FileCheck implemented there as it has a very specific use
while LLVMSupport is a dependency of pretty much every LLVM tool there is. In
fact, the only use of FileCheck I could find (outside the FileCheck tool and the
FileCheck unit test) is a single call in GISelMITest.h.
This moves the FileCheck logic to its own LLVMFileCheck library. This way only
FileCheck and the GlobalISelTests now have a dependency on this code.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D86344
The Length, AbbrOffset and Values fields of the debug_info section are
optional. This patch helps remove them and simplify test cases.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D86857
Add printf-style precision specifier to pad numbers to a given number of
digits when matching them if the value is smaller than the given
precision. This works on both empty numeric expression (e.g. variable
definition from input) and when matching a numeric expression. The
syntax is as follows:
[[#%.<precision><format specifier>, ...]
where <format specifier> is optional and ... can be a variable
definition or not with an empty expression or not. In the absence of a
precision specifier, a variable definition will accept leading zeros.
Reviewed By: jhenderson, grimar
Differential Revision: https://reviews.llvm.org/D81667
DFS and Reverse-DFS linkage orders are used to order execution of
deinitializers and initializers respectively.
This patch replaces uses of special purpose DFS order functions in
MachOPlatform and LLJIT with uses of the new methods.
This patch helps make the debug_abbrev_offset field optional. We don't
need to calculate the value of this field in the future.
Reviewed By: jhenderson
Differential Revision: https://reviews.llvm.org/D86614
This patch changes ElementCount so that the Min and Scalable
members are now private and can only be accessed via the get
functions getKnownMinValue() and isScalable(). In addition I've
added some other member functions for more commonly used operations.
Hopefully this makes the class more useful and will reduce the
need for calling getKnownMinValue().
Differential Revision: https://reviews.llvm.org/D86065
This adds all missing format values that are defined in
ELFObjectFile<ELFT>::getFileFormatName().
Differential revision: https://reviews.llvm.org/D86625
For StackLifetime after finding alloca we need to check that
values ponting to the begining of alloca.
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D86692
This patch optionally replaces the CRT allocator (i.e., malloc and free) with rpmalloc (mixed public domain licence/MIT licence) or snmalloc (MIT licence) or mimalloc (MIT licence). Please note that the source code for these allocators must be available outside of LLVM's tree.
To enable, use `cmake ... -DLLVM_INTEGRATED_CRT_ALLOC=D:/git/rpmalloc -DLLVM_USE_CRT_RELEASE=MT` where `D:/git/rpmalloc` has already been git clone'd from `https://github.com/mjansson/rpmalloc`. The same applies to snmalloc and mimalloc.
When enabled, the allocator will be embeded (statically linked) into the LLVM tools & libraries. This currently only works with the static CRT (/MT), although using the dynamic CRT (/MD) could potentially work as well in the future.
When enabled, this changes the memory stack from:
new/delete -> MS VC++ CRT malloc/free -> HeapAlloc -> VirtualAlloc
to:
new/delete -> {rpmalloc|snmalloc|mimalloc} -> VirtualAlloc
The goal of this patch is to bypass the application's global heap - which is thread-safe thus inducing locking - and instead take advantage of a modern lock-free, thread cache, allocator. On a 6-core Xeon Skylake we observe a 2.5x decrease in execution time when linking a large scale application with LLD and ThinLTO (12 min 20 sec -> 5 min 34 sec), when all hardware threads are being used (using LLD's flag /opt:lldltojobs=all). On a dual 36-core Xeon Skylake with all hardware threads used, we observe a 24x decrease in execution time (1 h 2 min -> 2 min 38 sec) when linking a large application with LLD and ThinLTO. Clang build times also see a decrease in the range 5-10% depending on the configuration.
Differential Revision: https://reviews.llvm.org/D71786