https://bugs.llvm.org/show_bug.cgi?id=44775

This rule has been implemented by GNU as https://sourceware.org/ml/binutils/2020-02/msg00028.html (binutils >= 2.35)

It allows us to simplify

```
.section .foo,"o",foo,unique,0
.section .foo,"o",bar,unique,1  # different section
```

to

```
.section .foo,"o",foo
.section .foo,"o",bar  # different section
```

We consider the two `.foo` different even if the linked-to symbols foo and bar
are defined in the same section.  This is a deliberate choice so that we don't
need to know the section where foo and bar are defined beforehand.

Differential Revision: https://reviews.llvm.org/D74006

While the function return updateImpl did only look at call sites the
manifest method looked at return values. If we don't do this during the
updateImpl we might create new abstract attributes during manifest. This
is a problem when it comes to liveness information.

If we simplify a function return value we have to modify the return
instructions.

If we see an undef we cannot assume it's the same as "no value". For now
we just collapse it to 0.

If we know a call was not needed we might have ended up deleting it even
if it was in a different SCC. This prevents us from doing so.

We can strip casts in AANoAlias but that might cause us to end up with a
non-pointer type. We do properly handle that case now.

This caused an error when passes iterated over cached assumptions in the
tracker and assumed them to be `null` or an instruction. I failed to
create a test case so far.

Emit{ValueTo,Code}Alignment Emit{DTP,TP,GP}* EmitSymbolValue etc

This follows http://blog.llvm.org/2019/11/deterministic-builds-with-clang-and-lld.html
to make the GN build locally deterministic.

With this, I've built lld at two different build paths on my Windows box and got
identical binaries. (I'd expect the same to happen on Linux, and with other
binaries.)

This doesn't have the bits to get universal determinism yet.

Differential Revision: https://reviews.llvm.org/D74519

SB API clients can describe the failure message in a more natural
way for their UI, this doesn't add information for them.

Differential Revision: https://reviews.llvm.org/D74585
<rdar://problem/49953304>

CallPreservedMask is used to describe the register liveness after a
function call. The function call in an interrupt handler should use the same
CallPreservedMask as normal functions. So that only callee save registers
can live through the function call.

In addition to memory behavior attributes (readonly/writeonly) we now
derive memory location attributes (argmemonly/inaccessiblememonly/...).
The former is part of AAMemoryBehavior and the latter part of
AAMemoryLocation. While they are similar in nature it got messy when
they were put in a single AA. Location attributes for arguments and
floating values will follow later.

Note that both memory attributes kinds can derive readnone. If there are
no accesses AAMemoryBehavior will derive readnone. If there are accesses
but only to stack (=local) locations AAMemoryLocation will derive
readnone.

Reviewed By: uenoku

Differential Revision: https://reviews.llvm.org/D73426

The dominator tree needs to be updated, but that isn't handled now.

This would assert on an unhandled size in getRegSplitParts.

Match the new DAG behavior and use v_perm_b32 when available. Also
does better on SI/CI by expanding 16-bit swaps. Also fix
non-power-of-2 cases.

Differential Revision: https://reviews.llvm.org/D74509

Summary:
Addresses PR44728 but no tests because I've not yet made any attempt to verify
correctness of the debug info.

Reviewers: sbc100, aardappel

Differential Revision: https://reviews.llvm.org/D74656

Due to the genericValueTraversal we might visit values for which we did
not create an AAValueConstantRange object, e.g., as they are behind a
PHI or select or call with `returned` argument. As a consequence we need
to validate the types as we are about to query AAValueConstantRange for
operands.

Summary:
Fix change from 8404aeb5 to avoid calling
computeHostNumPhysicalCores if LLVM_ENABLE_THREADS is off.

Reviewers: rnk, aganea

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D74654

Passing '-dlopen <library-path>' to lli will cause the specified library to be
loaded (via llvm::sys::DynamicLibrary::LoadLibraryPermanently) before JIT'd code
is executed, making the library's symbols accessible to JIT'd code.

This patch implements an almost complete handling of OpenMP
contexts/traits such that we can reuse most of the logic in Flang
through the OMPContext.{h,cpp} in llvm/Frontend/OpenMP.

All but construct SIMD specifiers, e.g., inbranch, and the device ISA
selector are define in `llvm/lib/Frontend/OpenMP/OMPKinds.def`. From
these definitions we generate the enum classes `TraitSet`,
`TraitSelector`, and `TraitProperty` as well as conversion and helper
functions in `llvm/lib/Frontend/OpenMP/OMPContext.{h,cpp}`.

The above enum classes are used in the parser, sema, and the AST
attribute. The latter is not a collection of multiple primitive variant
arguments that contain encodings via numbers and strings but instead a
tree that mirrors the `match` clause (see `struct OpenMPTraitInfo`).

The changes to the parser make it more forgiving when wrong syntax is
read and they also resulted in more specialized diagnostics. The tests
are updated and the core issues are detected as before. Here and
elsewhere this patch tries to be generic, thus we do not distinguish
what selector set, selector, or property is parsed except if they do
behave exceptionally, as for example `user={condition(EXPR)}` does.

The sema logic changed in two ways: First, the OMPDeclareVariantAttr
representation changed, as mentioned above, and the sema was adjusted to
work with the new `OpenMPTraitInfo`. Second, the matching and scoring
logic moved into `OMPContext.{h,cpp}`. It is implemented on a flat
representation of the `match` clause that is not tied to clang.
`OpenMPTraitInfo` provides a method to generate this flat structure (see
`struct VariantMatchInfo`) by computing integer score values and boolean
user conditions from the `clang::Expr` we keep for them.

The OpenMP context is now an explicit object (see `struct OMPContext`).
This is in anticipation of construct traits that need to be tracked. The
OpenMP context, as well as the `VariantMatchInfo`, are basically made up
of a set of active or respectively required traits, e.g., 'host', and an
ordered container of constructs which allows duplication. Matching and
scoring is kept as generic as possible to allow easy extension in the
future.

---

Test changes:

The messages checked in `OpenMP/declare_variant_messages.{c,cpp}` have
been auto generated to match the new warnings and notes of the parser.
The "subset" checks were reversed causing the wrong version to be
picked. The tests have been adjusted to correct this.
We do not print scores if the user did not provide one.
We print spaces to make lists in the `match` clause more legible.

Reviewers: kiranchandramohan, ABataev, RaviNarayanaswamy, gtbercea, grokos, sdmitriev, JonChesterfield, hfinkel, fghanim

Subscribers: merge_guards_bot, rampitec, mgorny, hiraditya, aheejin, fedor.sergeev, simoncook, bollu, guansong, dexonsmith, jfb, s.egerton, llvm-commits, cfe-commits

Tags: #clang, #llvm

Differential Revision: https://reviews.llvm.org/D71830

In 0e9b0b6d I introduced the
HistoryOperation enum to navigate the history. While this fixed the
behavior of HistoryOperation::Older and HistoryOperation::Newer, it
confused the mapping for HistoryOperation::Oldest and
HistoryOperation::Newest.

I tried to write a PExpect test to make sure this doesn't regress, but
I'm unable to prime the history in such a way that it recalls a known
element. I suspect this is an LLDB bug, but the  most recent entry
doesn't get update with entries from the current session. I considered
spoofing the home directory but that needs to happen before libLLDB is
loaded and you'll need to account for the widechar support. If anyone
has another suggestion I'd love to hear it.

[NFC][llvm-exegesis] CombinationGenerator::performGeneration(): pull put state increment into lambda

This avoids questionable code such as taking address of current
range-based for variable and comparing it with vector begin iterator.
While this may not be a problem in itself, it can be written more consice.
This was initially suggested by @aaronpuchert.

This change makes the following lit substitutions expand to the correct
thing for macOS, iOS, tvOS, and watchOS.

%darwin_min_target_with_full_runtime_arc_support
%macos_min_target_10_11

rdar://problem/59463146

rdar://problem/59466685

[compiler-rt] Provide a lit config variable that defines the minimum deployment OS version flag appropriate for the configured OS.

This patch defines `config.apple_platform_min_deployment_target_flag`
in the ASan, LibFuzzer, TSan, and UBSan lit test configs.

rdar://problem/59463146

rdar://problem/59463146

platforms.

For the simulators this changes the following compilation flags (
used both for building the runtime and lit tests).

iOS simulator: `-miphoneos-version-min` -> `-mios-simulator-version-min`
watchOS simulator: `-mwatchos-version-min` -> `-mwatchos-simulator-version-min`
tvOS simulator: `-mtvos-version-min` -> `-mtvos-simulator-version-min`

rdar://problem/59463146

[llvm-exegesis] Rename range based for loop variable in a unit test so its different than the container being iterated over. NFC

It seems like gcc 5.5 wants to iterate over the new variable instead
of the container that lives outside the loop. But of course this
new container is empty.

Plus using a different variable names makes the code more readable.

The array seemed to have decayed to a pointer before the ArrayRef
constructor got called so there was no size information available.