For swift async code, we need to use a debug intrinsic that behaves like
an llvm.dbg.declare but can take any location type rather than just a
pointer or integer.

To solve this, a new debug instrinsic called llvm.dbg.declare_value has
been created, which behaves exactly like an llvm.dbg.declare but can
take non pointer and integer location types.

More information here:
https://discourse.llvm.org/t/rfc-introduce-new-llvm-dbg-coroframe-entry-intrinsic/88269

This is the first patch as part of a stack of patches, with the one
succeeding it being: https://github.com/llvm/llvm-project/pull/168134

Since we currently only use the context information in the alloc info
summary in the LTO backend for assertion checking, there is no need to
write this into the combined summary index for distributed ThinLTO for
NDEBUG builds. Put this under a new -combined-index-memprof-context
option which is off by default for NDEBUG.

The advantage is that we save time (not having to sort in preparation
for building the radix trees), and space in the generated bitcode files.

We could also do so for the callsite info records, but those are smaller
and less expensive to prepare.

This reverts commit fdb050a5024320ec29d2edf3f2bc686c3a84abaa, and
restores ccb4702038900d82d1041ff610788740f5cef723, with a fix for build
bot failures.

Specifically, add ProfileData to the dependences of the BitWriter
library, which was causing shared library builds of LLVM to fail.
Reproduced the failure with a shared library build and confirmed this
change fixes that build failure.

Reverts llvm/llvm-project#117066

This is causing some build bot failures that need investigation.

Leverage the support added to represent allocation contexts in a more
compact way via a radix tree in the indexed profile to similarly reduce
sizes of the bitcode summaries.

For a large target, this reduced the size of the per-module summaries by
about 18% and in the distributed combined index files by 28%.

Improve the information printed when -memprof-report-hinted-sizes is
enabled. Now print the full context hash computed from the original
profile, similar to what we do when reporting matching statistics. This
will make it easier to correlate with the profile.

Note that the full context hash must be computed at profile match time
and saved in the metadata and summary, because we may trim the context
during matching when it isn't needed for distinguishing hotness.
Similarly, due to the context trimming, we may have more than one full
context id and total size pair per MIB in the metadata and summary,
which now get a list of these pairs.

Remove the old aggregate size from the metadata and summary support.
One other change from the prior support is that we no longer write the
size information into the combined index for the LTO backends, which
don't use this information, which reduces unnecessary bloat in
distributed index files.

This defines a new kind of IR Constant that represents a ptrauth signed
pointer, as used in AArch64 PAuth.

It allows representing most kinds of signed pointer constants used thus
far in the llvm ptrauth implementations, notably those used in the
Darwin and ELF ABIs being implemented for c/c++.  These signed pointer
constants are then lowered to ELF/MachO relocations.

These can be simply thought of as a constant `llvm.ptrauth.sign`, with
the interesting addition of discriminator computation: the `ptrauth`
constant can also represent a combined blend, when both address and
integer discriminator operands are used.  Both operands are otherwise
optional, with default values 0/null.

Reaplying after revert in #85382 (861ebe6446296c96578807363aa292c69d827773).
Fixed intermittent test failure by avoiding piping output in some RUN lines.

If --write-experimental-debuginfo-iterators-to-bitcode is true (default false)
and --expermental-debuginfo-iterators is also true then the new debug info
format (non-instruction records) is written to bitcode directly.

Added the following records:

    FUNC_CODE_DEBUG_RECORD_LABEL
    FUNC_CODE_DEBUG_RECORD_VALUE
    FUNC_CODE_DEBUG_RECORD_DECLARE
    FUNC_CODE_DEBUG_RECORD_ASSIGN
    FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE

The last one has an abbrev in FUNCTION_BLOCK BLOCK_INFO. Incidentally, this uses
the last value available without widening the code-length for FUNCTION_BLOCK
from 4 to 5 bits.

Records are formatted as follows:

    All DbgRecord start with:
      1. DILocation

      FUNC_CODE_DEBUG_RECORD_LABEL
        2. DILabel

      DPValues then share common fields:
        2. DILocalVariable
        3. DIExpression

        FUNC_CODE_DEBUG_RECORD_VALUE
          4. Location Metadata

        FUNC_CODE_DEBUG_RECORD_DECLARE
          4. Location Metadata

        FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE
	  4. Location Value (single)

        FUNC_CODE_DEBUG_RECORD_ASSIGN
	  4. Location Metadata
	  5. DIAssignID
	  6. DIExpression (address)
	  7. Location Metadata (address)

Encoding the DILocation metadata reference directly appeared to yield smaller
bitcode files than encoding the operands seperately (as is done with instruction
DILocations).

FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE is by far the most common DbgRecord record
in optimized code (order of 5x-10x over other kinds). Unoptimized code should
only contain FUNC_CODE_DEBUG_RECORD_DECLARE.

Reverts llvm/llvm-project#83251

Buildbot: https://lab.llvm.org/buildbot/#/builders/139/builds/61485

If --write-experimental-debuginfo-iterators-to-bitcode is true (default false)
and --expermental-debuginfo-iterators is also true then the new debug info
format (non-instruction records) is written to bitcode directly.

Added the following records:

    FUNC_CODE_DEBUG_RECORD_LABEL
    FUNC_CODE_DEBUG_RECORD_VALUE
    FUNC_CODE_DEBUG_RECORD_DECLARE
    FUNC_CODE_DEBUG_RECORD_ASSIGN
    FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE

The last one has an abbrev in FUNCTION_BLOCK BLOCK_INFO. Incidentally, this uses
the last value available without widening the code-length for FUNCTION_BLOCK
from 4 to 5 bits.

Records are formatted as follows:

    All DbgRecord start with:
      1. DILocation

      FUNC_CODE_DEBUG_RECORD_LABEL
        2. DILabel

      DPValues then share common fields:
        2. DILocalVariable
        3. DIExpression

        FUNC_CODE_DEBUG_RECORD_VALUE
          4. Location Metadata

        FUNC_CODE_DEBUG_RECORD_DECLARE
          4. Location Metadata

        FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE
	  4. Location Value (single)

        FUNC_CODE_DEBUG_RECORD_ASSIGN
	  4. Location Metadata
	  5. DIAssignID
	  6. DIExpression (address)
	  7. Location Metadata (address)

Encoding the DILocation metadata reference directly appeared to yield smaller
bitcode files than encoding the operands seperately (as is done with instruction
DILocations).

FUNC_CODE_DEBUG_RECORD_VALUE_SIMPLE is by far the most common DbgRecord record
in optimized code (order of 5x-10x over other kinds). Unoptimized code should
only contain FUNC_CODE_DEBUG_RECORD_DECLARE.