[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D115907

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Revert "[misexpect] Re-implement MisExpect Diagnostics"

This reverts commit 46774df307159444d65083c2fd82f8574f0ab1d9.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D115907

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Revert "[misexpect] Re-implement MisExpect Diagnostics"

This reverts commit 2add3fbd976d7b80a3a7fc14ef0deb9b1ca6beee.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D115907

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Revert "Revert "Revert "[misexpect] Re-implement MisExpect Diagnostics"""

This reverts commit 6cf560d69a222bff4af4e1d092437fd77f0f981c.

Revert "Revert "[misexpect] Re-implement MisExpect Diagnostics""

I mistakenly reverted my commit, so I'm relanding it.

This reverts commit 10866a1df4a82cdc54187330c509a2d46235455d.

Revert "[misexpect] Re-implement MisExpect Diagnostics"

This reverts commit e7749d4713a5ec886011ceb0fc821c6723061724.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Differential Revision: https://reviews.llvm.org/D115907

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Cleanup includes: Transform/Scalar

Estimated impact on preprocessor output line:
before: 1062981579
after: 1062494547

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

Cleanup includes: Transform/Scalar

Estimated impact on preprocessor output line:
before: 1062981579
after: 1062494547

Discourse thread: https://discourse.llvm.org/t/include-what-you-use-include-cleanup
Differential Revision: https://reviews.llvm.org/D120817

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[LowerExpectIntrinsic] Use cast<> instead of dyn_cast<> to avoid dereference of nullptr. NFC

[Transforms] Use make_early_inc_range (NFC)

[TargetTransformInfo] move branch probability query from TargetLoweringInfo

This is no-functional-change intended (NFC), but needed to allow
optimizer passes to use the API. See D98898 for a propose

[TargetTransformInfo] move branch probability query from TargetLoweringInfo

This is no-functional-change intended (NFC), but needed to allow
optimizer passes to use the API. See D98898 for a proposed usage
by SimplifyCFG.

I'm simplifying the code by removing the cl::opt. That was added
back with the original commit in D19488, but I don't see any
evidence in regression tests that it was used. Target-specific
overrides can use the usual patterns to adjust as necessary.
We could also restore that cl::opt, but it was not clear to me
exactly how to do it in the convoluted TTI class structure.

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[clang][CodeGen] Lower Likelihood attributes to @llvm.expect intrin instead of branch weights

08196e0b2e1f8aaa8a854585335c17ba479114df exposed LowerExpectIntrinsic's
internal implementation detail i

[clang][CodeGen] Lower Likelihood attributes to @llvm.expect intrin instead of branch weights

08196e0b2e1f8aaa8a854585335c17ba479114df exposed LowerExpectIntrinsic's
internal implementation detail in the form of
LikelyBranchWeight/UnlikelyBranchWeight options to the outside.

While this isn't incorrect from the results viewpoint,
this is suboptimal from the layering viewpoint,
and causes confusion - should transforms also use those weights,
or should they use something else, D98898?

So go back to status quo by making LikelyBranchWeight/UnlikelyBranchWeight
internal again, and fixing all the code that used it directly,
which currently is only clang codegen, thankfully,
to emit proper @llvm.expect intrinsics instead.

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Revert "[BranchProbability] move options for 'likely' and 'unlikely'"

Upon reviewing D98898 i've come to realization that these are
implementation detail of LowerExpectIntrinsicPass,
and they should

Revert "[BranchProbability] move options for 'likely' and 'unlikely'"

Upon reviewing D98898 i've come to realization that these are
implementation detail of LowerExpectIntrinsicPass,
and they should not be exposed to outside of it.

This reverts commit ee8b53815ddf6f6f94ade0068903cd5ae843fafa.

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[BranchProbability] move options for 'likely' and 'unlikely'

This makes the settings available for use in other passes by housing
them within the Support lib, but NFC otherwise.

See D98898 for the

[BranchProbability] move options for 'likely' and 'unlikely'

This makes the settings available for use in other passes by housing
them within the Support lib, but NFC otherwise.

See D98898 for the proposed usage in SimplifyCFG
(where this change was originally included).

Differential Revision: https://reviews.llvm.org/D98945

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Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"

See discussion in https://bugs.llvm.org/show_bug.cgi?id=45073 / https://reviews.llvm.org/D66324#2334485
the imp

Revert "clang-misexpect: Profile Guided Validation of Performance Annotations in LLVM"

See discussion in https://bugs.llvm.org/show_bug.cgi?id=45073 / https://reviews.llvm.org/D66324#2334485
the implementation is known-broken for certain inputs,
the bugreport was up for a significant amount of timer,
and there has been no activity to address it.
Therefore, just completely rip out all of misexpect handling.

I suspect, fixing it requires redesigning the internals of MD_misexpect.
Should anyone commit to fixing the implementation problem,
starting from clean slate may be better anyways.

This reverts commit 7bdad08429411e7d0ecd58cd696b1efe3cff309e,
and some of it's follow-ups, that don't stand on their own.

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Revert "Use uint64_t for branch weights instead of uint32_t"

This reverts commit 10f2a0d662d8d72eaac48d3e9b31ca8dc90df5a4.

More uint64_t overflows.

Use uint64_t for branch weights instead of uint32_t

CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64

Use uint64_t for branch weights instead of uint32_t

CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609

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Revert "Use uint64_t for branch weights instead of uint32_t"

This reverts commit e5766f25c62c185632e3a75bf45b313eadab774b.
Makes clang assert when building Chromium, see https://crbug.com/1142813
fo

Revert "Use uint64_t for branch weights instead of uint32_t"

This reverts commit e5766f25c62c185632e3a75bf45b313eadab774b.
Makes clang assert when building Chromium, see https://crbug.com/1142813
for a repro.

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Use uint64_t for branch weights instead of uint32_t

CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64

Use uint64_t for branch weights instead of uint32_t

CallInst::updateProfWeight() creates branch_weights with i64 instead of i32.
To be more consistent everywhere and remove lots of casts from uint64_t
to uint32_t, use i64 for branch_weights.

Reviewed By: davidxl

Differential Revision: https://reviews.llvm.org/D88609

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Implements [[likely]] and [[unlikely]] in IfStmt.

This is the initial part of the implementation of the C++20 likelihood
attributes. It handles the attributes in an if statement.

Differential Revis

Implements [[likely]] and [[unlikely]] in IfStmt.

This is the initial part of the implementation of the C++20 likelihood
attributes. It handles the attributes in an if statement.

Differential Revision: https://reviews.llvm.org/D85091

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Make helpers static. NFC.

Use std::make_tuple instead initializer list

Hopefully this pleases GCC-5 and fixes the build error:

LowerExpectIntrinsic.cpp:62:53: error: converting to
'std::tuple<unsigned int, unsigned int>' fr

Use std::make_tuple instead initializer list

Hopefully this pleases GCC-5 and fixes the build error:

LowerExpectIntrinsic.cpp:62:53: error: converting to
'std::tuple<unsigned int, unsigned int>' from initializer list would use
explicit constructor 'constexpr std::tuple<_T1, _T2>::tuple(_U1&&,
_U2&&) [with _U1 = llvm::cl::opt<unsigned int>&; _U2 =
llvm::cl::opt<unsigned int>&; <template-parameter-2-3> = void; _T1 =
unsigned int; _T2 = unsigned int]'
return {LikelyBranchWeight, UnlikelyBranchWeight};

Differential Revision: https://reviews.llvm.org/D82325

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Add support of __builtin_expect_with_probability

Add a new builtin-function __builtin_expect_with_probability and
intrinsic llvm.expect.with.probability.
The interface is __builtin_expect_with_proba

Add support of __builtin_expect_with_probability

Add a new builtin-function __builtin_expect_with_probability and
intrinsic llvm.expect.with.probability.
The interface is __builtin_expect_with_probability(long expr, long
expected, double probability).
It is mainly the same as __builtin_expect besides one more argument
indicating the probability of expression equal to expected value. The
probability should be a constant floating-point expression and be in
range [0.0, 1.0] inclusive.
It is similar to builtin-expect-with-probability function in GCC
built-in functions.

Differential Revision: https://reviews.llvm.org/D79830

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