[BOLT] Introduce binary analysis tool based on BOLT (#115330)

This initial commit does not add any specific binary analyses yet, it
merely contains the boilerplate to introduce a new BOLT-based too

[BOLT] Introduce binary analysis tool based on BOLT (#115330)

This initial commit does not add any specific binary analyses yet, it
merely contains the boilerplate to introduce a new BOLT-based tool.

This basically combines the 4 first patches from the prototype pac-ret
and stack-clash binary analyzer discussed in RFC
https://discourse.llvm.org/t/rfc-bolt-based-binary-analysis-tool-to-verify-correctness-of-security-hardening/78148
and published at
https://github.com/llvm/llvm-project/compare/main...kbeyls:llvm-project:bolt-gadget-scanner-prototype

The introduction of such a BOLT-based binary analysis tool was proposed
and discussed in at least the following places:
- The RFC pointed to above
- EuroLLVM 2024 round table
https://discourse.llvm.org/t/summary-of-bolt-as-a-binary-analysis-tool-round-table-at-eurollvm/78441
The round table showed quite a few people interested in being able to
build a custom binary analysis quickly with a tool like this.
- Also at the US LLVM dev meeting a few weeks ago, I heard interest from
a few people, asking when the tool would be available upstream.
- The presentation "Adding Pointer Authentication ABI support for your
ELF platform"
(https://llvm.swoogo.com/2024devmtg/session/2512720/adding-pointer-authentication-abi-support-for-your-elf-platform)
explicitly mentioned interest to extend the prototype tool to verify
correct implementation of pauthabi.

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[BOLT] Add profile density computation

Reuse the definition of profile density from llvm-profgen (#92144):
- the density is computed in perf2bolt using raw samples (perf.data or
pre-aggregated dat

[BOLT] Add profile density computation

Reuse the definition of profile density from llvm-profgen (#92144):
- the density is computed in perf2bolt using raw samples (perf.data or
pre-aggregated data),
- function density is the ratio of dynamically executed function bytes
to the static function size in bytes,
- profile density:
- functions are sorted by density in decreasing order, accumulating
their respective sample counts,
- profile density is the smallest density covering 99% of total sample
count.

In other words, BOLT binary profile density is the minimum amount of
profile information per function (excluding functions in tail 1% sample
count) which is sufficient to optimize the binary well.

The density threshold of 60 was determined through experiments with
large binaries by reducing the sample count and checking resulting
profile density and performance. The threshold is conservative.

perf2bolt would print the warning if the density is below the threshold
and suggest to increase the sampling duration and/or frequency to reach
a given density, e.g.:
```
BOLT-WARNING: BOLT is estimated to optimize better with 2.8x more samples.
```

Test Plan: updated pre-aggregated-perf.test

Reviewers: maksfb, wlei-llvm, rafaelauler, ayermolo, dcci, WenleiHe

Reviewed By: WenleiHe, wlei-llvm

Pull Request: https://github.com/llvm/llvm-project/pull/101094

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[BOLT] Enable standalone build (#97130)

Continue from #87196 as author did not have much time, I have taken over
working on this PR. We would like to have this so it'll be easier to
package for Ni

[BOLT] Enable standalone build (#97130)

Continue from #87196 as author did not have much time, I have taken over
working on this PR. We would like to have this so it'll be easier to
package for Nix.

Can be tested by copying cmake, bolt, third-party, and llvm directories
out into their own directory with this PR applied and then build bolt.

---------

Co-authored-by: pca006132 <john.lck40@gmail.com>

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[BOLT] Add -print-mappings option to heatmaps (#97567)

Emit a mapping in the legend between the characters/buckets and the text
sections, using:

```sh
llvm-heatmap-bolt -print-mappings ..
```

[BOLT] Add -print-mappings option to heatmaps (#97567)

Emit a mapping in the legend between the characters/buckets and the text
sections, using:

```sh
llvm-heatmap-bolt -print-mappings ..
```

Example:
```
Legend:
..
Sections:
a/A : .init 0x00000100-0x00000200
b/B : .plt 0x00000200-0x00000500
c/C : .text 0x00010000-0x000a0000
d/D : .fini 0x000a0000-0x000f0000
..
```

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[BOLT] Match functions with exact hash (#96572)

Added flag '--match-profile-with-function-hash' to match functions
based on exact hash. After identical and LTO name matching, more
functions can

[BOLT] Match functions with exact hash (#96572)

Added flag '--match-profile-with-function-hash' to match functions
based on exact hash. After identical and LTO name matching, more
functions can be recovered for inference with exact hash, in the case
of function renaming with no functional changes. Collisions are
possible in the unlikely case where multiple functions share the same
exact hash. The flag is off by default as it requires the processing of
all binary functions and subsequently is expensive.

Test Plan: added hashing-based-function-matching.test.

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Revert "[������] initial version"

This reverts commit bb5ab1ffe719f5e801ef08ac08be975546aa3266.

[������] initial version

Created using spr 1.3.4

Revert "[BOLT] Hash-based function matching" (#96568)

Reverts llvm/llvm-project#95821

[BOLT] Hash-based function matching (#95821)

Using the hashes of binary and profiled functions
to recover functions with changed names.

Test Plan: added
hashing-based-function-matching.test.

[BOLT] Add NamedRegionTimer to inferStaleProfile (#93078)

[BOLT] Output basic YAML profile in BAT mode

Relax assumptions that YAML output is not supported in BAT mode.
Set up basic infrastructure for emitting YAML for functions not covered
by BAT, such as

[BOLT] Output basic YAML profile in BAT mode

Relax assumptions that YAML output is not supported in BAT mode.
Set up basic infrastructure for emitting YAML for functions not covered
by BAT, such as from `.bolt.org.text` section (code identical to input binary
sans external refs), or non-rewritten functions in non-relocation mode (where
the function stays in the same section but BAT mapping is not emitted).

This diff only produces YAML profile for non-BAT functions (skipped,
non-simple). YAML profile for BAT functions is added in follow-up diffs:
- https://github.com/llvm/llvm-project/pull/76911 emits YAML profile with
internal control flow information only (branch profile),
- https://github.com/llvm/llvm-project/pull/76896 adds cross-function profile
(calls profile).

Test Plan: Added bolt/test/X86/bolt-address-translation-yaml.test

Reviewers: ayermolo, dcci, maksfb, rafaelauler

Reviewed By: rafaelauler

Pull Request: https://github.com/llvm/llvm-project/pull/76910

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[BOLT] Detect Linux kernel based on ELF program headers (#80086)

Check if program header addresses fall into the kernel space to detect a
Linux kernel binary on x86-64.

Delete opts::LinuxKernelM

[BOLT] Detect Linux kernel based on ELF program headers (#80086)

Check if program header addresses fall into the kernel space to detect a
Linux kernel binary on x86-64.

Delete opts::LinuxKernelMode and use BinaryContext::IsLinuxKernel
instead.

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[BOLT] Refactor --keep-nops option. NFC. (#72228)

Run RemoveNops pass only if --keep-nops is set to false (default).

[BOLT] Fix NOP instruction emission on x86 (#72186)

Use MCAsmBackend::writeNopData() interface to emit NOP instructions on
x86. There are multiple forms of NOP instruction on x86 with different
si

[BOLT] Fix NOP instruction emission on x86 (#72186)

Use MCAsmBackend::writeNopData() interface to emit NOP instructions on
x86. There are multiple forms of NOP instruction on x86 with different
sizes. Currently, LLVM's assembly/disassembly does not support all forms
correctly which can lead to a breakage of input code semantics, e.g. if
the program relies on NOP instructions for reserving a patch space.

Add "--keep-nops" option to preserve NOP instructions.

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[BOLT] Fix typos (#68121)

Closes https://github.com/llvm/llvm-project/issues/63097

Before merging please make sure the change to
bolt/include/bolt/Passes/StokeInfo.h is correct.

bolt/include/

[BOLT] Fix typos (#68121)

Closes https://github.com/llvm/llvm-project/issues/63097

Before merging please make sure the change to
bolt/include/bolt/Passes/StokeInfo.h is correct.

bolt/include/bolt/Passes/StokeInfo.h

```diff
// This Pass solves the two major problems to use the Stoke program without
- // proting its code:
+ // probing its code:
```

I'm still not happy about the awkward wording in this comment.

bolt/include/bolt/Passes/FixRelaxationPass.h

```
$ ed -s bolt/include/bolt/Passes/FixRelaxationPass.h <<<'9,12p'
// This file declares the FixRelaxations class, which locates instructions with
// wrong targets and fixes them. Such problems usually occures when linker
// relaxes (changes) instructions, but doesn't fix relocations types properly
// for them.
$
```


bolt/docs/doxygen.cfg.in
bolt/include/bolt/Core/BinaryContext.h
bolt/include/bolt/Core/BinaryFunction.h
bolt/include/bolt/Core/BinarySection.h
bolt/include/bolt/Core/DebugData.h
bolt/include/bolt/Core/DynoStats.h
bolt/include/bolt/Core/Exceptions.h
bolt/include/bolt/Core/MCPlusBuilder.h
bolt/include/bolt/Core/Relocation.h
bolt/include/bolt/Passes/FixRelaxationPass.h
bolt/include/bolt/Passes/InstrumentationSummary.h
bolt/include/bolt/Passes/ReorderAlgorithm.h
bolt/include/bolt/Passes/StackReachingUses.h
bolt/include/bolt/Passes/StokeInfo.h
bolt/include/bolt/Passes/TailDuplication.h
bolt/include/bolt/Profile/DataAggregator.h
bolt/include/bolt/Profile/DataReader.h
bolt/lib/Core/BinaryContext.cpp
bolt/lib/Core/BinarySection.cpp
bolt/lib/Core/DebugData.cpp
bolt/lib/Core/DynoStats.cpp
bolt/lib/Core/Relocation.cpp
bolt/lib/Passes/Instrumentation.cpp
bolt/lib/Passes/JTFootprintReduction.cpp
bolt/lib/Passes/ReorderData.cpp
bolt/lib/Passes/RetpolineInsertion.cpp
bolt/lib/Passes/ShrinkWrapping.cpp
bolt/lib/Passes/TailDuplication.cpp
bolt/lib/Rewrite/BoltDiff.cpp
bolt/lib/Rewrite/DWARFRewriter.cpp
bolt/lib/Rewrite/RewriteInstance.cpp
bolt/lib/Utils/CommandLineOpts.cpp
bolt/runtime/instr.cpp
bolt/test/AArch64/got-ld64-relaxation.test
bolt/test/AArch64/unmarked-data.test
bolt/test/X86/Inputs/dwarf5-cu-no-debug-addr-helper.s
bolt/test/X86/Inputs/linenumber.cpp
bolt/test/X86/double-jump.test
bolt/test/X86/dwarf5-call-pc-function-null-check.test
bolt/test/X86/dwarf5-split-dwarf4-monolithic.test
bolt/test/X86/dynrelocs.s
bolt/test/X86/fallthrough-to-noop.test
bolt/test/X86/tail-duplication-cache.s
bolt/test/runtime/X86/instrumentation-ind-calls.s

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[BOLT] Add -dump-cg option to dump call graph

Reviewed By: #bolt, rafauler

Differential Revision: https://reviews.llvm.org/D153994

[BOLT] Control aggregation mode output profile file format

In perf2bolt and `-aggregate-only` BOLT mode, the output profile file is written
in fdata format by default. Provide a knob `-profile-forma

[BOLT] Control aggregation mode output profile file format

In perf2bolt and `-aggregate-only` BOLT mode, the output profile file is written
in fdata format by default. Provide a knob `-profile-format=[fdata,yaml]` to
control the format.
Note that `-w` option still dumps in YAML format.

Reviewed By: #bolt, maksfb

Differential Revision: https://reviews.llvm.org/D133995

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CommandLine: add and use cl::SubCommand::get{All,TopLevel}

Prefer using these accessors to access the special sub-commands
corresponding to the top-level (no subcommand) and all sub-commands.

This

CommandLine: add and use cl::SubCommand::get{All,TopLevel}

Prefer using these accessors to access the special sub-commands
corresponding to the top-level (no subcommand) and all sub-commands.

This is a preparatory step towards removing the use of ManagedStatic:
with a subsequent change, these global instances will be moved to
be regular function-scope statics.

It is split up to give downstream projects a (albeit short) window in
which they can switch to using the accessors in a forward-compatible
way.

Differential Revision: https://reviews.llvm.org/D129118

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[BOLT] Increase coverage of shrink wrapping [3/5]

Add the option to run -equalize-bb-counts before shrink
wrapping to avoid unnecessarily optimizing some CFGs where profile is
inaccurate but we can

[BOLT] Increase coverage of shrink wrapping [3/5]

Add the option to run -equalize-bb-counts before shrink
wrapping to avoid unnecessarily optimizing some CFGs where profile is
inaccurate but we can prove two blocks have the same frequency.

Reviewed By: Amir

Differential Revision: https://reviews.llvm.org/D126113

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[bolt] Remove unneeded cl::ZeroOrMore for cl::opt options

Remove unneeded cl::ZeroOrMore for cl::opt options

Similar to 557efc9a8b68628c2c944678c6471dac30ed9e8e.
This commit handles options where cl::ZeroOrMore is more than one line below
cl::opt.

[Hexagon][bolt] Remove unneeded cl::ZeroOrMore for cl::opt options. NFC

Similar to 557efc9a8b68628c2c944678c6471dac30ed9e8e

[BOLT] Check if LLVM_REVISION is defined

Handle the case where LLVM_REVISION is undefined (due to LLVM_APPEND_VC_REV=OFF
or otherwise) by setting "<unknown>" value as before D123549.

Reviewed By: y

[BOLT] Check if LLVM_REVISION is defined

Handle the case where LLVM_REVISION is undefined (due to LLVM_APPEND_VC_REV=OFF
or otherwise) by setting "<unknown>" value as before D123549.

Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D123852

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[BOLT][NFC] Use LLVM_REVISION instead of BOLT_VERSION_STRING

Remove duplicate version string identification

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D123549

[BOLT] Set cold sections alignment explicitly

The cold text section alignment is set using the maximum alignment value
passed to the emitCodeAlignment. In order to calculate tentetive layout
right w

[BOLT] Set cold sections alignment explicitly

The cold text section alignment is set using the maximum alignment value
passed to the emitCodeAlignment. In order to calculate tentetive layout
right we will set the minimum alignment of such sections to the maximum
possible function alignment explicitly.

Differential Revision: https://reviews.llvm.org/D121392

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