Extend the `uwtable` attribute with unwind table kind

We have the `clang -cc1` command-line option `-funwind-tables=1|2` and
the codegen option `VALUE_CODEGENOPT(UnwindTables, 2, 0) ///< Unwind
tabl

Extend the `uwtable` attribute with unwind table kind

We have the `clang -cc1` command-line option `-funwind-tables=1|2` and
the codegen option `VALUE_CODEGENOPT(UnwindTables, 2, 0) ///< Unwind
tables (1) or asynchronous unwind tables (2)`. However, this is
encoded in LLVM IR by the presence or the absence of the `uwtable`
attribute, i.e. we lose the information whether to generate want just
some unwind tables or asynchronous unwind tables.

Asynchronous unwind tables take more space in the runtime image, I'd
estimate something like 80-90% more, as the difference is adding
roughly the same number of CFI directives as for prologues, only a bit
simpler (e.g. `.cfi_offset reg, off` vs. `.cfi_restore reg`). Or even
more, if you consider tail duplication of epilogue blocks.
Asynchronous unwind tables could also restrict code generation to
having only a finite number of frame pointer adjustments (an example
of *not* having a finite number of `SP` adjustments is on AArch64 when
untagging the stack (MTE) in some cases the compiler can modify `SP`
in a loop).
Having the CFI precise up to an instruction generally also means one
cannot bundle together CFI instructions once the prologue is done,
they need to be interspersed with ordinary instructions, which means
extra `DW_CFA_advance_loc` commands, further increasing the unwind
tables size.

That is to say, async unwind tables impose a non-negligible overhead,
yet for the most common use cases (like C++ exceptions), they are not
even needed.

This patch extends the `uwtable` attribute with an optional
value:
- `uwtable` (default to `async`)
- `uwtable(sync)`, synchronous unwind tables
- `uwtable(async)`, asynchronous (instruction precise) unwind tables

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D114543

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[UpdateTestChecks][FIX] Expected output changed with Attributor

[test] Use -passes in lit tests for the UpdateTestChecks tool

The UpdateTestChecks tool itself does not care about which pass
manager that is used in the opt invocation. So the lit tests that
are ve

[test] Use -passes in lit tests for the UpdateTestChecks tool

The UpdateTestChecks tool itself does not care about which pass
manager that is used in the opt invocation. So the lit tests that
are verifying the behavior of the UpdateTestChecks tool is updated
to use the new-PM syntax (-passes=) when specifying the pass pipeline
in the test cases that are used for verifying the UpdateTestChecks
tool.

Differential Revision: https://reviews.llvm.org/D114517

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[Utils] Check for more global information in update_test_checks

This allows to check for various globals (metadata/attributes/...) and
also resolves problems with globals (metadata/attributes/...) b

[Utils] Check for more global information in update_test_checks

This allows to check for various globals (metadata/attributes/...) and
also resolves problems with globals (metadata/attributes/...) being
reused across different prefixes.

Reviewed By: sstefan1

Differential Revision: https://reviews.llvm.org/D94741

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[UpdateTestChecks] include { in function signature check line

After D85099, if we have attribute group in the function signature that hasn't
been seen before, and later a callsite with the same attr

[UpdateTestChecks] include { in function signature check line

After D85099, if we have attribute group in the function signature that hasn't
been seen before, and later a callsite with the same attribute group, filecheck will evaluate
the first attribute group to for example '#0 {'. We now include { in the args_and_sig group to avoid this.

Differential Revision: https://reviews.llvm.org/D86769

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[UpdateTestChecks] Match unnamed values like "@[0-9]+" and "![0-9]+"

With this patch we will match most *uses* of "temporary" named things in
the IR via regular expressions, not their name at creati

[UpdateTestChecks] Match unnamed values like "@[0-9]+" and "![0-9]+"

With this patch we will match most *uses* of "temporary" named things in
the IR via regular expressions, not their name at creation time. The new
"values" we match are:
- "unnamed" globals: `@[0-9]+`
- debug metadata: `!dbg ![0-9]+`
- loop metadata: `!loop ![0-9]+`
- tbaa metadata: `!tbaa ![0-9]+`
- range metadata: `!range ![0-9]+`
- generic metadata: `metadata ![0-9]+`
- attributes groups: `#[0-9]`

We still don't match the declarations but that can be done later. This
patch can introduce churn when existing check lines contain the old
hardcoded versions of the above "values". We can add a flag to opt-out,
or opt-in, if necessary.

Reviewed By: arichardson, MaskRay

Differential Revision: https://reviews.llvm.org/D85099

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[Utils][Fix] remove unnecessary ; at the end

[Utils] Check function attributes in update_test_checks

Summary:
This introduces new flag to the update_test_checks and
update_cc_test_checks that allows for function attributes
to be checked in a c

[Utils] Check function attributes in update_test_checks

Summary:
This introduces new flag to the update_test_checks and
update_cc_test_checks that allows for function attributes
to be checked in a check-line. If the flag is not set,
the behavior should remain the same.

Reviewers: jdoerfert

Subscribers: arichardson, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D83629

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