Summary:
In case a pointer iterator is incremented in a binary plus expression
(operator+), where the iterator is on the RHS, IteratorModeling should
now detect, and track the resulting value.

Reviewers: Szelethus, baloghadamsoftware

Reviewed By: baloghadamsoftware

Subscribers: rnkovacs, whisperity, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, steakhal, martong, ASDenysPetrov, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D83190

http://lab.llvm.org:8011/builders/clang-cmake-x86_64-avx2-linux/builds/15710/steps/build%20stage%201/logs/stdio
fails with:

/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp: In function ‘llvm::Expected<const llvm::object::Elf_Mips_Options<ELFT>*> readMipsOptions(const uint8_t*, llvm::ArrayRef<unsigned char>&, bool&)’:
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:3373:19: error: the value of ‘ExpectedSize’ is not usable in a constant expression
     if (O->size < ExpectedSize)
                   ^
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:3369:10: note: ‘size_t ExpectedSize’ is not const
   size_t ExpectedSize =
          ^
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:3373:12: error: parse error in template argument list
     if (O->size < ExpectedSize)
            ^
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp: In instantiation of ‘llvm::Expected<const llvm::object::Elf_Mips_Options<ELFT>*> readMipsOptions(const uint8_t*, llvm::ArrayRef<unsigned char>&, bool&) [with ELFT = llvm::object::ELFType<(llvm::support::endianness)0u, true>; uint8_t = unsigned char]’:
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:3400:30:   required from ‘void {anonymous}::ELFDumper<ELFT>::printMipsOptions() [with ELFT = llvm::object::ELFType<(llvm::support::endianness)0u, true>]’
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:2878:21:   required from ‘void {anonymous}::ELFDumper<ELFT>::printArchSpecificInfo() [with ELFT = llvm::object::ELFType<(llvm::support::endianness)0u, true>]’
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:6999:1:   required from here
/home/ssglocal/clang-cmake-x86_64-avx2-linux/clang-cmake-x86_64-avx2-linux/llvm/llvm/tools/llvm-readobj/ELFDumper.cpp:3373:5: error: ‘size’ is not a member template function

Fix: add 2 `const` words to variables.

`printMipsOptions()` and the test related has the following issues currently:

1) It does not check the value of Elf_Mips_Options<ELFT>::size field.
2) For ODK_REGINFO options it is possible to read past the end of buffer,
   because there is no check against the `sizeof(Elf_Mips_RegInfo<ELFT>)`.
3) The error about the broken size is just printed to the standard output.
4) The binary input is used for the test.
5) There is no testing for multiple options in the .MIPS.options section,
   though the code supports it.
6) Only llvm-readobj is tested, but not llvm-readelf.
7) "Unsupported MIPS options tag" message does not reveal the tag ID/name.

This patch fixes all of these points.

Differential revision: https://reviews.llvm.org/D84854

DWARFYAML supports generating the .debug_loclists section. We can use it
to simplify tests.

Reviewed By: jhenderson, grimar

Differential Revision: https://reviews.llvm.org/D85179

Added a "clone" of the 1D vector's test_transfer_read and added a second dimensionality. The test is not as generic as I would like it to be, because more generic versions appear to break the compiler or the runtime at this stage. As bug are fixed, I will be happy to add another more complete test.

Differential Revision: https://reviews.llvm.org/D83096

See bug https://bugs.llvm.org/show_bug.cgi\?id\=46976

It turns out that findSectionByName can return
const Elf_Shdr * instead of Expected<>, because its
code never returns an error currently (it reports warnings instead).

Differential revision: https://reviews.llvm.org/D85135

For FP_TO_INT and INT_TO_FP lowering, we have direct-move and
non-direct-move methods. But they share some conversion logic, so we can
reduce redundant code by introducing new methods.

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D81818

Compared to the optimized code with branch conditions never frozen,
limiting the type of freeze's operand causes generation of suboptimal code in
some cases.
I would like to suggest removing the constraint, as this patch does.
If the number of freeze instructions becomes significant, this can be revisited.

Differential Revision: https://reviews.llvm.org/D84949

Lowering of newly defined Conv ops in TC syntax to standard
dialect is not supported and therefore this commit adds support
for it.

Differential Revision: https://reviews.llvm.org/D84840

Fixes https://github.com/clangd/clangd/issues/476

Differential Revision: https://reviews.llvm.org/D85108

D84723 caused multiple definition issues (related to comdat) on Windows:
http://lab.llvm.org:8011/builders/sanitizer-windows/builds/67465

Test function mask_cmp_128 failed during ISEL
LLVM ERROR: Cannot select: t37: v8i1 = X86ISD::KSHIFTL t48, TargetConstant:i8<4>
due to v8i1 only available under AVX512DQ.

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D84922

Reviewed By: steven.zhang

Differential Revision: https://reviews.llvm.org/D84735

When scavenging consider the sub-register of the source operand
to determine the bank of a candidate register (not just sub0).
Without this it is possible to introduce an infinite loop,
e.g. $sgpr15_sgpr16_sgpr17 can be assigned for a conflict between
$sgpr0 and SGPR_96:sub1.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D84910

See https://lists.llvm.org/pipermail/llvm-dev/2020-July/143373.html
"[llvm-dev] Multiple documents in one test file" for some discussions.

This patch has explored several alternatives. The current semantics are similar to
what @dblaikie proposed.
`split-file filename output` splits the input file into multiple parts separated by
regex `^(.|//)--- filename` and write each part to the file `output/filename`
(`filename` can include path separators).

Use case A (organizing input of different formats (e.g. linker
script+assembly) in one file).

```
# RUN: split-file %s %t
# RUN: llvm-mc %t/asm -o %t.o
# RUN: ld.lld -T %t/lds %t.o -o %t
This is sometimes better than the %S/Inputs/ approach because the user
can see the auxiliary files immediately and don't have to open another file.

# asm
...
# lds
...
```

Use case B (for utilities which don't have built-in input splitting
feature):

```
// RUN: split-file %s %t
// RUN: llc < %t/1.ll | FileCheck %s --check-prefix=CASE1
// RUN: l...

D68041 placed `__profc_`,  `__profd_` and (if exists) `__profvp_` in different comdat groups.
There are some issues:

* Cost: one or two additional section headers (`.group` section(s)): 64 or 128 bytes on ELF64.
* `__profc_`,  `__profd_` and (if exists) `__profvp_` should be retained or
  discarded. Placing them into separate comdat groups is conceptually inferior.
* If the prevailing group does not include `__profvp_` (value profiling not
  used) but a non-prevailing group from another translation unit has `__profvp_`
  (the function is inlined into another and triggers value profiling), there
  will be a stray `__profvp_` if --gc-sections is not enabled.
  This has been fixed by 3d6f5301.

Actually, we can reuse an existing symbol (we choose `__profd_`) as the group
signature to avoid a string in the string table (the sole reason that D68041
could improve code size is that `__profv_` was an otherwise unused symbol which
wasted string table space). This saves one or two section headers.

For a -DCMAKE_BUILD_TYPE=Release -DLLVM_BUILD_INSTRUMENTED=IR build, `ninja
clang lld`, the patch has saved 10.5MiB (2.2%) for the total .o size.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D84723

[SimpleLoopUnswitch][NFC] Add option to always drop make.implicit metadata in non-trivial unswitching and save compile time

We might want this if we find out that using of MustExecute analysis is too expensive.
By default we do the analysis because its complexity does not exceed the complexity
of whole loop copying in unswitching. Follow-up for D84925.

Differential Revision: https://reviews.llvm.org/D85001
Reviewed By: asbirlea

Sometimes the decorator is used on a common function rather than the
test method, which can return a value. This fails with decorators that
use skipTestIfFn under the hood.

This reverts commit adb5c23f. It surprisingly fails on a windows build bot: http://lab.llvm.org:8011/builders/lldb-x64-windows-ninja/builds/18009

Will reland after some investigation and/or after adding some extra logging to help debug the issue.

Reviewed By: lebedev.ri
Differential Revision: https://reviews.llvm.org/D85130

Differential Revision: https://reviews.llvm.org/D85166

Clang and GCC have a feature (-MD flag) to create a dependency file
in a format that build systems such as Make or Ninja can read, which
specifies all the additional inputs such .h files.

This change introduces the same functionality to lld bringing it to
feature parity with ld and gold which gained this feature recently.
See https://sourceware.org/bugzilla/show_bug.cgi?id=22843 for more
details and discussion.

The implementation corresponds to -MD -MP compiler flag where the
generated dependency file also includes phony targets which works
around the errors where the dependency is removed. This matches the
format used by ld and gold.

Fixes PR42806

Differential Revision: https://reviews.llvm.org/D82437

External input was detecting "end of file" conditions in
BeginExternal...Input() and BeginUnformattedInput() routines
before EnableHandlers() could have been called.  Defer the
"start next record" processing to the input data item
handlers (and EndIoStatement() for when there are no data
items).

Differential Revision: https://reviews.llvm.org/D85161

Extend the raw file wrapper to get accessibility, positioning,
and size information.  This is needed for INQUIRE (to follow).

Differential Revision: https://reviews.llvm.org/D85160

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D85156

If the test suite is misconfigured when it's run (a bad regexp, wrong test directory, etc.), the test suite may not discover any tests. When this happens, the test runner exits happily because no tests failed:

```
Ran 0 tests in 0.000s
RESULT: PASSED (0 passes, 0 failures, 0 errors, 0 skipped, 0 expected failures, 0 unexpected successes)
```

Change this to return an error so the misconfiguration can be more easily detected. Verified that `lldb-dotest -p TestDoesNotExist.py` successfully fails.

Reviewed By: JDevlieghere

Differential Revision: https://reviews.llvm.org/D85169

Fixes problems in FCVS test fm110.f.
Add more comments, too.

Differential Revision: https://reviews.llvm.org/D85163

Adds the function createMCInst() to MCContext that creates a MCInst using
a typed bump alloctor.

MCInst contains a SmallVector<MCOperand, 8>. The SmallVector is POD only
for <= 8 operands. The default untyped bump pointer allocator of MCContext
does not delete the MCInst, so if the SmallVector grows, it's a leak.

This fixes https://bugs.llvm.org/show_bug.cgi?id=46900.

In order to follow NEC Aurora SX VE ABI correctly, change to sign/zero
extend integer arguments and return values smaller than 64 bits in clang.
Also update regression test.

Reviewed By: simoll

Differential Revision: https://reviews.llvm.org/D85071

Differential Revision: https://reviews.llvm.org/D85151

Reviewed By: dmgreen

Differential Revision: https://reviews.llvm.org/D85152

These UBSan tests assert the absence of runtime errors via `count 0`,
which means "expect no output".  This fails the test unnecessarily in
some environments (e.g., iOS simulator in our case).  Alter the test to
be a bit more specific and "expect no error" instead of "expect no
output".

rdar://65503408

Differential Revision: https://reviews.llvm.org/D85155