CodeGen: Remove AliasAnalysis from regalloc

This was stored in LiveIntervals, but not actually used for anything
related to LiveIntervals. It was only used in one check for if a load
instruction is

CodeGen: Remove AliasAnalysis from regalloc

This was stored in LiveIntervals, but not actually used for anything
related to LiveIntervals. It was only used in one check for if a load
instruction is rematerializable. I also don't think this was entirely
correct, since it was implicitly assuming constant loads are also
dereferenceable.

Remove this and rely only on the invariant+dereferenceable flags in
the memory operand. Set the flag based on the AA query upfront. This
should have the same net benefit, but has the possible disadvantage of
making this AA query nonlazy.

Preserve the behavior of assuming pointsToConstantMemory implying
dereferenceable for now, but maybe this should be changed.

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[mlgo] Support exposing more features than those supported by models

This allows the compiler to support more features than those supported by a
model. The only requirement (development mode only) i

[mlgo] Support exposing more features than those supported by models

This allows the compiler to support more features than those supported by a
model. The only requirement (development mode only) is that the new
features must be appended at the end of the list of features requested
from the model. The support is transparent to compiler code: for
unsupported features, we provide a valid buffer to copy their values;
it's just that this buffer is disconnected from the model, so insofar
as the model is concerned (AOT or development mode), these features don't
exist. The buffers are allocated at setup - meaning, at steady state,
there is no extra allocation (maintaining the current invariant). These
buffers has 2 roles: one, keep the compiler code simple. Second, allow
logging their values in development mode. The latter allows retraining
a model supporting the larger feature set starting from traces produced
with the old model.

For release mode (AOT-ed models), this decouples compiler evolution from
model evolution, which we want in scenarios where the toolchain is
frequently rebuilt and redeployed: we can first deploy the new features,
and continue working with the older model, until a new model is made
available, which can then be picked up the next time the compiler is built.

Differential Revision: https://reviews.llvm.org/D124565

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[mlgo] Fix build breaks introduced by includes cleanups

These were not detected by the build bots because those went quietly
offline, too, due to a misconfiguration (fixed since)

Cleanup codegen includes

This is a (fixed) recommit of https://reviews.llvm.org/D121169

after: 1061034926
before: 1063332844

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-in

Cleanup codegen includes

This is a (fixed) recommit of https://reviews.llvm.org/D121169

after: 1061034926
before: 1063332844

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D121681

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Revert "Cleanup codegen includes"

This reverts commit 7f230feeeac8a67b335f52bd2e900a05c6098f20.
Breaks CodeGenCUDA/link-device-bitcode.cu in check-clang,
and many LLVM tests, see comments on https:/

Revert "Cleanup codegen includes"

This reverts commit 7f230feeeac8a67b335f52bd2e900a05c6098f20.
Breaks CodeGenCUDA/link-device-bitcode.cu in check-clang,
and many LLVM tests, see comments on https://reviews.llvm.org/D121169

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Cleanup codegen includes

after: 1061034926
before: 1063332844

Differential Revision: https://reviews.llvm.org/D121169

[nfc][mlgo][regalloc] Stop warnings about unused function

Added a `NoopSavedModelImpl` type which can be used as a mock AOT-ed
saved model, and further minimize conditional compilation cases. This
a

[nfc][mlgo][regalloc] Stop warnings about unused function

Added a `NoopSavedModelImpl` type which can be used as a mock AOT-ed
saved model, and further minimize conditional compilation cases. This
also removes unused function warnings on gcc.

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[nfc][mlgo][regalloc] Cache live interval feature components

Lazily cache the feature components of a LiveInterval.

Differential Revision: https://reviews.llvm.org/D118674

[nfc][regalloc] const LiveIntervals within the allocator

Once built, LiveIntervals are immutable. This patch captures that.

Differential Revision: https://reviews.llvm.org/D118918

Revert "[nfc][mlgo] De-const a parameter"

This reverts commit bc3b372161716a4c4845d47a877e4892df0d08da.

The planned change that would have needed non-const MachineFunction refs
isn't needed after a

Revert "[nfc][mlgo] De-const a parameter"

This reverts commit bc3b372161716a4c4845d47a877e4892df0d08da.

The planned change that would have needed non-const MachineFunction refs
isn't needed after all.

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Fix buildbreak introduced in ed2deab5956fea9e8f64ef6020fe0b4e19734ecc

[nfc][regalloc] Make the max inference cutoff configurable

Added a flag to make configurable the number of interferences after
which we 'bail out' and treat a set of intervals as un-evictable. Also

[nfc][regalloc] Make the max inference cutoff configurable

Added a flag to make configurable the number of interferences after
which we 'bail out' and treat a set of intervals as un-evictable. Also
using it on the ML side, as it turns out to be a good control for
compile-time.

With this configurable, we can do a bit of trial and error and see if
bumping it has any effect on heuristic/policy quality.

Differential Revision: https://reviews.llvm.org/D118707

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[nfc][mlgo][regalloc] 'hasPreferredPhys' out of feature components

It isn't cacheable, it can be updated by other events than live interval
resizing.

[mlgo][regalloc] Factor live interval feature calculation

Factoring it out so we can subsequently cache it. This should be a NFC,
however, for the float quantities, we see small errors in the least

[mlgo][regalloc] Factor live interval feature calculation

Factoring it out so we can subsequently cache it. This should be a NFC,
however, for the float quantities, we see small errors in the least
significant digits. This is because, before, we were summing up one by
one. Now, we sum up results of sums.

This shouldn't matter for ML, and will require rework when we do
quantization (avoiding floats altogether), but meanwhile, it did require
an update to the reference file used for testing.

The patch also bumps the precision of the variables involved in this, to
reduce the error (note they are casted back to float at the end by the
SET macro, since we only work with float and not double in TF)

Differential Revision: https://reviews.llvm.org/D118659

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[nfc][mlgo] De-const a parameter

We plan to pass the MachineFunction& to APIs that expect it non-const
(for legitimate reasons). The advisor still holds the ref as a const
ref, though, so we keep mo

[nfc][mlgo] De-const a parameter

We plan to pass the MachineFunction& to APIs that expect it non-const
(for legitimate reasons). The advisor still holds the ref as a const
ref, though, so we keep most of the maintainability value of that.

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[mlgo][regalloc] Fix -Wunused-variable in -DLLVM_ENABLE_ASSERTIONS=off builds after a8a7bf922cea8af01168f7a4adf4ed0365bcc2b4

[mlgo][regalloc] Fix register masking

If AllocationOrder has less than 32 elements, we were treating the extra
positions as if they were valid. This was detected by a subsequent
assert. The fix also

[mlgo][regalloc] Fix register masking

If AllocationOrder has less than 32 elements, we were treating the extra
positions as if they were valid. This was detected by a subsequent
assert. The fix also tightens the asserts.

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[NFC][MLGO] Simplify conditional compilation

Most of the code that's shared between 'release' and 'development'
modes doesn't depend on anything special.

[MLGO] Improved support for AOT cross-targeting scenarios

The tensorflow AOT compiler can cross-target, but it can't run on (for
example) arm64. We added earlier support where the AOT-ed header and

[MLGO] Improved support for AOT cross-targeting scenarios

The tensorflow AOT compiler can cross-target, but it can't run on (for
example) arm64. We added earlier support where the AOT-ed header and object
would be built on a separate builder and then passed at build time to
a build host where the AOT compiler can't run, but clang can be otherwise
built.

To simplify such scenarios given we now support more than one AOT-able
case (regalloc and inliner), we make the AOT scenario centered on whether
files are generated, case by case (this includes the "passed from a
different builder" scenario).
This means we shouldn't need an 'umbrella' LLVM_HAVE_TF_AOT, in favor of
case by case control. A builder can opt out of an AOT case by passing that case's
model path as `none`. Note that the overrides still take precedence.

This patch controls conditional compilation with case-specific flags,
which can be enabled locally, for the component where those are
available. We still keep an overall flag for some tests.

The 'development/training' mode is unchanged, because there the model is
passed from the command line and interpreted.

Differential Revision: https://reviews.llvm.org/D117752

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Fix build break introduced by D117147

[MLGO] ML Regalloc Eviction Advisor

The bulk of the implementation is common between 'release' mode (==AOT-ed
model) and 'development' mode (for training), the main difference is
that in development

[MLGO] ML Regalloc Eviction Advisor

The bulk of the implementation is common between 'release' mode (==AOT-ed
model) and 'development' mode (for training), the main difference is
that in development mode, we may also log features (for training logs),
inject scoring information (currently after the Virtual Register
Rewriter) and then produce the log file.

This patch also introduces the score injection pass, 'Register
Allocation Pass Scoring', which is trivially just logging the score in
development mode.

Differential Revision: https://reviews.llvm.org/D117147

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[NFC][MLGO] The regalloc reward is float, not int64_t

[NFC][MLGO] Prep a few files before the main ML Regalloc adviser

To avoid trivial changes.

Ensure newlines at the end of files (NFC)

[NFC][mlgo] Add feature declarations for the ML regalloc advisor

This just adds feature declarations and some boilerplate.

Differential Revision: https://reviews.llvm.org/D116076