There are optimized out with -fno-builtin

There were invalid DIE references which nobody used. If LLDB starts to
report invalid DIE references it would lock up (mutex lock).

These invalid DIE references are there since initial check-in by:
  https://reviews.llvm.org/D83302

isNoopIntrinsic returns true for some intrinsics that are modeled in
MemorySSA but do not actually read or write any memory and do not block
DSE. Such intrinsics should not be considered as read-clobbers.

Differential Revision: https://reviews.llvm.org/D89624

This pattern was repeated a few times, and for some reason always
using insert or try_emplace, even though we know in advance that
we're looking for an existing entry and not trying to create a
new one.

- Removing unused and unusable code.

Reviewers: krytarowski

Reviewed By: krytarowski

Differential Revision: https://reviews.llvm.org/D89640

This implements the likelihood attribute for the switch statement. Based on the
discussion in D85091 and D86559 it only handles the attribute when placed on
the case labels or the default labels.

It also marks the likelihood attribute as feature complete. There are more QoI
patches in the pipeline.

Differential Revision: https://reviews.llvm.org/D89210

This adds 2 new tests from PR47887 and regenerates the check lines for
the file.

A patchset being prepared shows needless diffs.

Only PowerPC and RISCV need to override it.

Nothing ever calls it with anything other than the default value.
So just delete it and the code that handled the non-default value.

D39386 made CalleeSavedInfo possible to spill a register to another register
(vector register for POWER9) but did not actually test live-in.

[X86] Mark the Key Locker instructions as NotMemoryFoldable to make the X86FoldTablesEmitter not crash.

loadiwkey and aesenc128kl share the same opcode but one is memory
and one is register. But they're behavior is quite different. We
were crashing because one has an output register and one doesn't
and the backend couldn't account for that. But since they aren't
foldable we can just add NotMemoryFoldable so they won't be looked at.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D89602

Rather then querying first and then checking additional conditions,
check the conditions first. They are much cheaper than the alias
query.

DataLayout is always around...

This reverts commit b77dd32a. Sanitizer tests are broken.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D89602

It's not pretty, but probably better than modelling it
as an opaque SCEVUnknown, i guess.

It is relevant e.g. for the loop that was brought up in
https://bugs.llvm.org/show_bug.cgi?id=46786#c26
as an example of what we'd be able to better analyze
once SCEV handles `ptrtoint` (D89456).

But as it is evident, even if we deal with `ptrtoint` there,
we also fail to model such an `ashr`.
Also, modeling of mul-of-exact-shr/div could use improvement.

As per alive2:
https://alive2.llvm.org/ce/z/tnfZKd
```
define i8 @src(i8 %0) {
  %2 = ashr exact i8 %0, 4
  ret i8 %2
}

declare i8 @llvm.abs(i8, i1)
declare i8 @llvm.smin(i8, i8)
declare i8 @llvm.smax(i8, i8)

define i8 @tgt(i8 %x) {
  %abs_x = call i8 @llvm.abs(i8 %x, i1 false)
  %div = udiv exact i8 %abs_x, 16
  %t0 = call i8 @llvm.smax(i8 %x, i8 -1)
  %t1 = call i8 @llvm.smin(i8 %t0, i8 1)
  %r = mul nsw i8 %div, %t1
  ret i8 %r
}
```
Transformation seems to be correct!

This reverts commit b2eb4393.

Caused the regression:
https://bugs.llvm.org/show_bug.cgi?id=47589

Reviewed By: MyDeveloperDay

Differential Revision: https://reviews.llvm.org/D89464

Differential Revision: https://reviews.llvm.org/D86395

These tests pass for RV64 Linux, but they are marked as XFAIL. This patch
fixes that.

Differential Revision: https://reviews.llvm.org/D89299

These two cases should be using the same logic. Not NFC, as this
resolves the TODO regarding use of the underlying object.

This patch fixes a couple of typos in the LoopUnrollPass.cpp comments

Differential Revision: https://reviews.llvm.org/D89603

This adds some basic costs for MVE reductions - currently just costing
the simple legal add vectors as a single MVE instruction. More complex
costing can be added in the future when the framework more readily
allows it.

Differential Revision: https://reviews.llvm.org/D88980

This adds a very basic cost for active_lane_mask under MVE - making the
assumption that they will be free and then apologizing for that in a
comment.

In reality they may either be free (by being nicely folded into a tail
predicated loop), cost the same as a VCTP or be expanded into vdup's,
adds and cmp's. It is difficult to detect the difference from a single
getIntrinsicInstrCost call, so makes the assumption that the vectorizer
is adding them, and only added them where it makes sense.

We may need to change this in the future to better model predicate costs
in the vectorizer, especially at -Os or non-tail predicated loops. The
vectorizer currently does not query the cost of these instructions but
that will change in the future and a zero cost there probably makes the
most sense at the moment.

Differential Revision: https://reviews.llvm.org/D88989

In lldb, explicitly set the "option() honors normal variables" CMake policy. This applies for
standalone lldb builds and matches what llvm, clang, etc do. This prevents potentially unwanted
clearing of variables like `LLVM_ENABLE_WARNINGS`, and also prevents unnecessary build warnings.

See: https://cmake.org/cmake/help/latest/policy/CMP0077.html

Differential Revision: https://reviews.llvm.org/D89614

Unbreak module builds.

TargetCXXABI.def has been removed in a revert: 79829a47.

This reverts commit 0ff9116b.

it was ending up in a code block from the previous section,
instead of being its own section.