When we have a zeroext parameter coming in on the stack, build

```
%x = G_LOAD ...
%x_assert_zext = G_ASSERT_ZEXT %x, narrow_size
%trunc = G_TRUNC %x_assert_zext
```

Rather than just loading into the truncated type.

This allows us to optimize cases like this: https://godbolt.org/z/vfjhW8

Differential Revision: https://reviews.llvm.org/D95805

This completes libc++'s implementation of
P0879 "Constexpr for swap and swap related functions."
http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2018/p0879r0.html

For the feature-macro adjustment, see
https://cplusplus.github.io/LWG/issue3256

Differential Revision: https://reviews.llvm.org/D93661

Adding this, since there's currently no documentation about this.

Differential Revision: https://reviews.llvm.org/D95911

Use mapAnyOf() and matchers based on it.

Use of binaryOperation() means that modernize-loop-convert and
readability-container-size-empty can now be used with rewritten binary
operators.

Differential Revision: https://reviews.llvm.org/D94131

when rewriting 'a < b' as '(a <=> b) < 0'.

It's pretty common for comparison category types to use a pointer or
pointer-to-member type as their '0' parameter.

This reverts commit 6a59f056, because
it is causing failures on green dragon.

This reverts commit 7a6a2cc8 because
it is causing failures on green dragon.

This reverts commit 0d487cf8 because
it is causing failures on green dragon.

This turns on the new pass manager by default for the optimization pipeline in
Clang and ThinLTO in various LLD backends. This also makes uses of `opt
-instcombine` use the new pass manager (unless specifically opted out).

This does not affect the backend target-dependent codegen pipeline.

If this causes regressions, you can opt out of the new pass manager
either via the -DENABLE_EXPERIMENTAL_NEW_PASS_MANAGER=OFF CMake flag
while building LLVM, or via various compiler flags, e.g.
-flegacy-pass-manager for Clang or -Wl,--lto-legacy-pass-manager for
ELF LLD. Please file bugs for any regressions.

Major differences:
* The inliner works slightly differently
* -O1 does some amount of inlining
* LCSSA and LoopSimplify are run before all loop passes
* Loop unswitching is implemented slightly differently
* A new SpeculateAroundPHIs pass is added to the pipeline

https://lists.llvm.org/pipermail/llvm-dev/2021-January/148098.html

Reviewed By: asbirlea, ychen, MaskRay, echr...

This is a corner of the differences between C99 designators and C++20
designators that we'd previously overlooked. As with other such cases,
this continues to be permitted as an extension and allowed by default,
behind the -Wc99-designators warning flag, except in cases where it
leads to a conformance difference (such as in overload resolution and in
a SFINAE context).

This is the G_SEXT counterpart to the existing G_ZEXT/G_ANYEXT combines.

Differential Revision: https://reviews.llvm.org/D95729

Honor the CPU type (and subtype) when launching the inferior on macOS.

Part of this functionality was thought to be no longer needed and
removed in 85bd4369, however it's still
needed, for example to launch binaries under Rosetta 2 on Apple Silicon.

This patch will use posix_spawnattr_setarchpref_np if available and
fallback to posix_spawnattr_setbinpref_np if not.

Differential revision: https://reviews.llvm.org/D95922

Clang usually propagates counter mapping region for conditions of `if`, `while`,
`for`, etc from parent counter. We should do the same for condition of conditional operator.

Differential Revision: https://reviews.llvm.org/D95918

- Implement C++20's changes to `reverse_iterator`, so that it won't be
    accidentally counted as a contiguous iterator in C++20 mode.
- Implement C++20's changes to `move_iterator` as well.
- `move_iterator` should not be contiguous. This fixes a bug where
    we optimized `std::copy`-of-move-iterators in an observable way.
    Add a regression test for that bugfix.
- Add libcxx tests for `__is_cpp17_contiguous_iterator` of all relevant
    standard iterator types. Particularly check that vector::iterator
    is still considered contiguous in all C++ modes, even C++03.

After this patch, there continues to be no supported way to write your
own iterator type in C++17-and-earlier such that libc++ will consider it
"contiguous"; however, we now fully support the C++20 approach (in C++20
mode only). If you want user-defined contiguous iterators in C++17-and-earlier,
libc++'s position is "please upgrade to C++20."

Differential Revision: https://reviews.llvm.org/D94807

This just exposes a missing API

Differential Revision: https://reviews.llvm.org/D95968

To prevent creating a new component, which creates a new library.

Reviewed By: ychen

Differential Revision: https://reviews.llvm.org/D95907

AsanThread::Destroy implementation expected to be called on
child thread.

I missed authors concern regarding this reviewing D95184.

Reviewed By: delcypher

Differential Revision: https://reviews.llvm.org/D95731

Reviewed By: herhut

Differential Revision: https://reviews.llvm.org/D94421

rdar://73742471
Differential Revision: https://reviews.llvm.org/D95695

This patch detaches SampleProfileLoader from class
SampleCoverageTracker. We plan to move SampleProfileLoader
to a template class. This would remain SampleCoverageTracker
as a class.
Also make callsiteIsHot() as a file static function.

Differential Revision: https://reviews.llvm.org/D95823

Extract registering device variable to CUDA runtime codegen function since it
will be called in multiple places.

Reviewed by: Artem Belevich

Differential Revision: https://reviews.llvm.org/D95558

Differential Revision: https://reviews.llvm.org/D95857

These two cases have identical implementations other than an
unreachable part of `G_ADD` that checks if the scalar we're narrowing
is a vector. Combining them to avoid unnecessary divergence.

Differential Revision: https://reviews.llvm.org/D95856

This was only adding undef to the use if the copy itself had a
subregister index. It did not consider the subrange liveness if the
use had a subreg index to begin with.

Constant folding for calls to LBOUND() was not working when the lower bound of
a constant array was not 1.

I fixed this and re-enabled the test in Evaluate/folding16.f90 that previously
was silently failing.  I slightly changed the test to parenthesize the first
argument to exercise all of the new code.

Differential Revision: https://reviews.llvm.org/D95894

Reviewed-by: morehouse

Differential Revision: https://reviews.llvm.org/D95923

Reviewed-by: morehouse

Differential Revision: https://reviews.llvm.org/D95957

This expands the pattern suggest in https://reviews.llvm.org/D95850 to all
math functions.

Fuchsia is migrating to a variable page size.

Reviewed By: phosek, charco

Differential Revision: https://reviews.llvm.org/D95919

Per https://reviews.llvm.org/D94938#inline-896740.

Per https://reviews.llvm.org/D95121#inline-897943.

This extends {D92539} to work even when we are loading archive
members via `-force_load`. I uncovered this issue while trying to
force-load archives containing bitcode -- we were segfaulting.

In addition to fixing the `-force_load` case, this diff also addresses
the behavior of `-ObjC` when LTO bitcode is involved -- we need to
force-load those archive members if they contain ObjC categories.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D95265

This makes our error messages more informative. But the bigger motivation is for
LTO symbol resolution, which will be in an upcoming diff. The changes in this
one are largely mechanical.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D94316

If we had a pair of copies inside a loop which introduced new liveness
to a subregister which was undef before the loop, we would have a
dummy phi-only segment remaining across the loop body. Later, this
false segment would confuse RenameIndependentSubregs causing it to
introduce IMPLICIT_DEFs with broken value numbering.

It seems always adding the lanes to ShrinkMask is OK, so any
conditions should be purely a compile time filter.