This implements the following changes:
* AutoType retains sugared deduced-as-type.
* Template argument deduction machinery analyses the sugared type all the way
down. It would previously lose the sugar on first recursion.
* Undeduced AutoType will be properly canonicalized, including the constraint
template arguments.
* Remove the decltype node created from the decltype(auto) deduction.

As a result, we start seeing sugared types in a lot more test cases,
including some which showed very unfriendly `type-parameter-*-*` types.

Signed-off-by: Matheus Izvekov <mizvekov@gmail.com>

Reviewed By: rsmith

Differential Revision: https://reviews.llvm.org/D110216

[X86][ABI] Change the alignment of f80 in 32-bit calling convention to meet with different data layout

Reviewed By: RKSimon

Differential Revision: https://reviews.llvm.org/D113739

It fails to detect a single leak with GLIBC 2.34.

(Split from D113167)
Benchmarking on one of our large apps which exports a few thousands symbols,
this showed an improvement of ~17%.

x ./LLD_no_parallel.txt
+ ./LLD_with_parallel.txt

    N           Min           Max        Median           Avg        Stddev
x  10         84.01         89.41         88.64        87.693     1.7424061
+  10          71.9         74.29         72.63        72.753    0.77734663
Difference at 95.0% confidence
	-14.94 +/- 1.26763
	-17.0367% +/- 1.44553%
	(Student's t, pooled s = 1.34912)

(wallclock)

Differential Revision: https://reviews.llvm.org/D113820

Similar to how the other swift sections are registered by the ORC
runtime's macho platform, add the __swift5_types section, which contains
type metadata. Add a simple test that demonstrates that the swift
runtime recognized the registered types.

rdar://85358530

Differential Revision: https://reviews.llvm.org/D113811

We had two identical RV64I RUN lines. One should be RV32I.

category is empty

Currently, if we create a category in ObjC that is empty, we still emit
runtime metadata for that category. This is a scenario that could
commonly be run into when using __attribute__((objc_direct_members)),
which elides the need for much of the category metadata. This is
slightly wasteful and can be easily skipped by checking the category
metadata contents during CodeGen.

rdar://66177182

Differential Revision: https://reviews.llvm.org/D113455

Since glibc 2.34, dlsym does
  1. malloc 1
  2. malloc 2
  3. free pointer from malloc 1
  4. free pointer from malloc 2
These sequence was not handled by trivial dlsym hack.

This fixes https://bugs.llvm.org/show_bug.cgi?id=52278

Reviewed By: eugenis, morehouse

Differential Revision: https://reviews.llvm.org/D112588

This is one of those wonderful "in theory X doesn't matter, but in practice is does" changes. In this particular case, we shift the IVs inserted by the runtime unroller to clamp iteration count of the loops* from decrementing to incrementing.

Why does this matter?  A couple of reasons:
* SCEV doesn't have a native subtract node.  Instead, all subtracts (A - B) are represented as A + -1 * B and drops any flags invalidated by such.  As a result, SCEV is slightly less good at reasoning about edge cases involving decrementing addrecs than incrementing ones.  (You can see this in the inferred flags in some of the test cases.)
* Other parts of the optimizer produce incrementing IVs, and they're common in idiomatic source language.  We do have support for reversing IVs, but in general if we produce one of each, the pair will persist surprisingly far through the optimizer before being coalesced.  (You can see this looking at nearby phis in the test cases.)

Note that if the hardware prefers decrementing (i.e. zero tested) loops, LSR should convert back immediately before codegen.

* Mostly irrelevant detail: The main loop of the prolog case is handled independently and will simple use the original IV with a changed start value.  We could in theory use this scheme for all iteration clamping, but that's a larger and more invasive change.

I'm disabling this test until the fix is reviewed
(here https://reviews.llvm.org/D113650/)

The division by constant optimization often produces constants that
are uimm32, but not simm32. These constants require 3 or 4 instructions
to materialize without Zba.

Since these instructions are often used by a multiply with a LHS
that needs to be zero extended with an AND, we can switch the MUL
to a MULHU by shifting both inputs left by 32. Once we shift the
constant left, the upper 32 bits no longer need to be 0 so constant
materialization is free to use LUI+ADDIW. This reduces the constant
materialization from 4 instructions to 3 in some cases while also
reducing the zero extend of the LHS from 2 shifts to 1.

Differential Revision: https://reviews.llvm.org/D113805

No functionality change here; just unblocking a patch to LLVM.

Fix some confusion between the two types of `const` a pointer/iterator
can have. Users of a SwitchInst::CaseIterator should not (and do not!)
manually mutate the SwitchInst::CaseHandle that tracks its internal
state. Change operator*() to return `const CaseHandle&`, remove the
non-const-qualified operator*(), and const-qualify
CaseHandle::setValue() and CaseHandle::setSuccessor().

Differential Revision: https://reviews.llvm.org/D113788

Take advantage of class name injection to avoid redundantly specifying
template parameters of iterator adaptor/facade base classes.

No functionality change, although the private typedefs changed in a
couple of cases.

  - Added a private typedef HashTableIterator::BaseT, following the
    pattern from r207084 / 3478d4b1, to
    pre-emptively appease MSVC (maybe it's not necessary anymore but
    looks like we do this pretty consistently). Otherwise, I removed
    private
  - Removed private typedefs filter_iterator_impl::BaseT and
    FilterIteratorTest::InputIterator::BaseT since there was only one
    use of each and the definition was no longer interesting.

* The format_arg attribute tells the compiler that the attributed function
  returns a format string that is compatible with a format string that is being
  passed as a specific argument.
* Several NSString methods return copies of their input, so they would ideally
  have the format_arg attribute. A previous differential (D112670) added
  support for instancetype methods having the format_arg attribute when used
  in the context of NSString method declarations.
* D112670 failed to account that instancetype can be sugared in certain narrow
  (but critical) scenarios, like by using nullability specifiers. This patch
  resolves this problem.

Differential Revision: https://reviews.llvm.org/D113636
Reviewed By: ahatanak

Radar-Id: rdar://85278860

We missed the tests in the earlier XFAIL-ing because the locale.fr_FR.UTF-8
feature wasn't available, but since an upgrade these are now showing up
on the CI.

Differential Revision: https://reviews.llvm.org/D113791

Depends on D113331

Reviewed By: jpienaar

Differential Revision: https://reviews.llvm.org/D113714

Fortran defines an ENTRY point name as being pure if its enclosing
subprogram scope defines a pure procedure.

Differential Revision: https://reviews.llvm.org/D113711

Fixes PR52385

Similar to D113702, but for the LSDAs. Clang seems to emit all LSDA
relocs as section relocs, but ld -r can turn those relocs into symbol
ones.

Reviewed By: #lld-macho, oontvoo

Differential Revision: https://reviews.llvm.org/D113721

Dedup'ing unwind info is tricky because each CUE contains a different
function address, if ICF operated naively and compared the entire
contents of each CUE, entries with identical unwind info but belonging
to different functions would never be considered identical. To work
around this problem, we slice away the function address before
performing ICF. We rely on `relocateCompactUnwind()` to correctly handle
these truncated input sections.

Here are the numbers before and after D109944, D109945, and this diff
were applied, as tested on my 3.2 GHz 16-Core Intel Xeon W:

Without any optimizations:

             base           diff           difference (95% CI)
  sys_time   0.849 ± 0.015  0.896 ± 0.012  [  +4.8% ..   +6.2%]
  user_time  3.357 ± 0.030  3.512 ± 0.023  [  +4.3% ..   +5.0%]
  wall_time  3.944 ± 0.039  4.032 ± 0.031  [  +1.8% ..   +2.6%]
  samples    40             38

With `-dead_strip`:

             base           diff           difference (95% CI)
  sys_time   0.847 ± 0.010  0.896 ± 0.012  [  +5.2% ..   +6.5%]
  user_time  3.377 ± 0.014  3.532 ± 0.015  [  +4.4% ..   +4.8%]
  wall_time  3.962 ± 0.024  4.060 ± 0.030  [  +2.1% ..   +2.8%]
  samples    47             30

With `-dead_strip` and `--icf=all`:

             base           diff           difference (95% CI)
  sys_time   0.935 ± 0.013  0.957 ± 0.018  [  +1.5% ..   +3.2%]
  user_time  3.472 ± 0.022  6.531 ± 0.046  [ +87.6% ..  +88.7%]
  wall_time  4.080 ± 0.040  5.329 ± 0.060  [ +30.0% ..  +31.2%]
  samples    37             30

Unsurprisingly, ICF is now a lot slower, likely due to the much larger
number of input sections it needs to process. But the rest of the
linker only suffers a mild slowdown.

Note that the compact-unwind-bad-reloc.s test was expanded because we
now handle the relocation for CUE's function address in a separate code
path from the rest of the CUE relocations. The extended test covers both
code paths.

Reviewed By: #lld-macho, oontvoo

Differential Revision: https://reviews.llvm.org/D109946

These patterns were noted in the recent D113212 and follow-ups.
I did not bother to duplicate every test because it should be
clear if we recognize the swaps from a smaller sample. We have
complete coverage for the original patterns.

Previously we set `isFuncEntry` flag  to true when the funcName from DWARF is equal to the name in symbol table and we use this flag to ignore reporting callsite sample that's from an intra func branch. However, in HHVM, it appears that the symbol table name is inconsistent with the dwarf info func name, it's likely due to `OptimizeGlobalAliases`.

This change is a workaround in llvm-profgen side to mark the only one range as the function entry and add warnings for the remaining inconsistence.

This also fixed a missing `getCanonicalFnName` for symbol name which caused the mismatching as well.

Reviewed By: hoy, wenlei

Differential Revision: https://reviews.llvm.org/D113492

We only need to expose setDecl, copyArray and the actOn* methods.

Instead of pretending that function pointer type aliases or variables
are functions, and thereby losing the information that they are type
aliases or variables, respectively, we use the existence of a return
type in the DeclInfo to signify a "function-like" object.

That seems pretty natural, since it's also the return type (or parameter
list) from the DeclInfo that we compare the documentation with.

Addresses a concern voiced in D111264#3115104.

Reviewed By: gribozavr2

Differential Revision: https://reviews.llvm.org/D113691

Then we don't have to look into the declaration again. Also it's only
natural to collect this information alongside parameters and return
type, as it's also just a parameter in some sense.

Reviewed By: gribozavr2

Differential Revision: https://reviews.llvm.org/D113690

We noticed that the library structure causes link ordering problems in Google's internal build. However, we don't think the problem is specific to Google's build, it probably can be reproduced anywhere with the right library structure.

In general splitting the Python bindings from their dependencies (the C API targets) creates the possibility that the two libraries might end up in the wrong order on the linker command line. We can avoid this problem happening by reverting the structure of the MLIRBindingsPythonCore to represent its dependencies in the usual way, rather than composing an incomplete `MLIRBindingsPythonCoreNoCAPI` target and their CAPI dependencies. It was probably a mistake to rewrite this particular `cc_library()` rule in terms of the two, since nothing guarantees that the two will be correctly ordered by the linker when both are being linked into the same binary, and it was only an incidental "cleanup...

Clang seems to emit all functionAddress relocs as section relocs, but
`ld -r` can turn those relocs into symbol ones. It turns out that we
weren't handling that case correctly when the symbol was a weak def
whose definition did not prevail.

Reviewed By: #lld-macho, oontvoo

Differential Revision: https://reviews.llvm.org/D113702

Part of the very first discussion here, but didn't upstream it before as we
didn't use it yet. Fix that for pending updates. Just adding the op here,
follow up will add the lowering to codegen.

`const`-qualify ParsedAttr::iterator::operator*(), clearing up confusion
about the two meanings of const for pointers/iterators. Helps unblock
removal of (non-const) iterator_facade_base::operator->().

Change the non-const version of findCaseValue() to forward to the const
version.

The unrolling code was previously inserting new cloned blocks at the end of the function.  The result of this with typical loop structures is that the new iterations are placed far from the initial iteration.

With unrolling, the general assumption is that the a) the loop is reasonable hot, and b) the first Count-1 copies of the loop are rarely (if ever) loop exiting.  As such, placing Count-1 copies out of line is a fairly poor code placement choice.  We'd much rather fall through into the hot (non-exiting) path.  For code with branch profiles, later layout would fix this, but this may have a positive impact on non-PGO compiled code.

However, the real motivation for this change isn't performance.  Its readability and human understanding.  Having to jump around long distances in an IR file to trace an unrolled loop structure is error prone and tedious.

Profiling a basic internal real input read benchmark shows some
hot spots in the code used to prepare input for decimal-to-binary
conversion, which is of course where the time should be spent.
The library that implements decimal to/from binary conversions has
been optimized, but not the code in the Fortran runtime that calls it,
and there are some obvious light changes worth making here.

Move some member functions from *.cpp files into the class definitions
of Descriptor and IoStatementState to enable inlining and specialization.

Make GetNextInputBytes() the new basic input API within the
runtime, replacing GetCurrentChar() -- which is rewritten in terms of
GetNextInputBytes -- so that input routines can have the
ability to acquire more than one input character at a time
and amortize overhead.

These changes speed up the time to read 1M random reals
using internal I/O from a character array from 1.29s to 0.54s
on my machine, which on par w...

Previously if you passed `-oso_prefix path/to/foo/` with a trailing
slash at the end, using `real_path` would remove that slash, but that
slash is necessary to make sure OSO prefix paths end up as valid
relative paths instead of starting with `/`.

Differential Revision: https://reviews.llvm.org/D113541

This fixes const-correctness of iterator adaptors, dropping non-`const`
overloads for `operator*()`.

Iterators, like the pointers that they generalize, have two types of
`const`.

The `const` qualifier on members indicates whether the iterator itself
can be changed. This is analagous to `int *const`.

The `const` qualifier on return values of `operator*()`, `operator[]()`,
and `operator->()` controls whether the the pointed-to value can be
changed. This is analogous to `const int *`.

Since `operator*()` does not (in principle) change the iterator, then
there should only be one definition, which is `const`-qualified. E.g.,
iterators wrapping `int*` should look like:
```
int *operator*() const; // always const-qualified, no overloads
```

ba7a6b31 changed `iterator_adaptor_base`
away from this to work around bugs in other iterator adaptors. That was
already reverted. This patch adds back its test, which combined
llvm::enumerate() and llvm::make_filter_range(), adds a test for
iterator_adaptor_base itself, and cleans up the `const`-ness of the
other iterator adaptors.

This also updates the documented requirements for
`iterator_facade_base`:
```
/// OLD:
///   - const T &operator*() const;
///   - T &operator*();

/// New:
///   - T &operator*() const;
```
In a future commit we might also clean up `iterator_facade`'s overloads
of `operator->()` and `operator[]()`. These already (correctly) return
non-`const` proxies regardless of the iterator's `const` qualifier.

Differential Revision: https://reviews.llvm.org/D113158