[BOLT][AArch64] Handle gold linker veneers

The gold linker veneers are written between functions without symbols,
so we to handle it specially in BOLT.

Vladislav Khmelevsky,
Advanced Software Techn

[BOLT][AArch64] Handle gold linker veneers

The gold linker veneers are written between functions without symbols,
so we to handle it specially in BOLT.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Differential Revision: https://reviews.llvm.org/D129260

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[BOLT] Fix getDynoStats to handle BCs with no functions

Address fuzzer crash

Reviewed By: yota9

Differential Revision: https://reviews.llvm.org/D120696

Revert "[BOLT][AArch64] Handle gold linker veneers"

This reverts commit 425dda76e9fac93117289fd68a2abdfb1e4a0ba5.

This commit is currently causing BOLT to crash in one of our
binaries and needs a b

Revert "[BOLT][AArch64] Handle gold linker veneers"

This reverts commit 425dda76e9fac93117289fd68a2abdfb1e4a0ba5.

This commit is currently causing BOLT to crash in one of our
binaries and needs a bit more checking to make sure it is safe
to land.

show more ...

[BOLT][AArch64] Handle gold linker veneers

The gold linker veneers are written between functions without symbols,
so we to handle it specially in BOLT.

Vladislav Khmelevsky,
Advanced Software Techn

[BOLT][AArch64] Handle gold linker veneers

The gold linker veneers are written between functions without symbols,
so we to handle it specially in BOLT.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

Differential Revision: https://reviews.llvm.org/D128082

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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.

[BOLT] Cache-Aware Tail Duplication

A new "cache-aware" strategy for tail duplication.

Differential Revision: https://reviews.llvm.org/D123050

[BOLT] CMOVConversion pass

Convert simple hammocks into cmov based on misprediction rate.

Test Plan:
- Assembly test: `cmov-conversion.s`
- Testing on a binary:
# Bootstrap clang with `-x86-cmov-

[BOLT] CMOVConversion pass

Convert simple hammocks into cmov based on misprediction rate.

Test Plan:
- Assembly test: `cmov-conversion.s`
- Testing on a binary:
# Bootstrap clang with `-x86-cmov-converter-force-all` and `-Wl,--emit-relocs`
(Release build)
# Collect perf.data:

- `clang++ <opts> bolt/lib/Core/BinaryFunction.cpp -E > bf.cpp`
- `perf record -e cycles:u -j any,u -- clang-15 bf.cpp -O2 -std=c++14 -c -o bf.o`
# Optimize clang-15 with and w/o -cmov-conversion:
- `llvm-bolt clang-15 -p perf.data -o clang-15.bolt`
- `llvm-bolt clang-15 -p perf.data -cmov-conversion -o clang-15.bolt.cmovconv`
# Run perf experiment:
- test: `clang-15.bolt.cmovconv`,
- control: `clang-15.bolt`,
- workload (clang options): `bf.cpp -O2 -std=c++14 -c -o bf.o`
Results:
```
task-clock [delta: -360.21 ± 356.75, delta(%): -1.7760 ± 1.7589, p-value: 0.047951, balance: -6]
instructions [delta: 44061118 ± 13246382, delta(%): 0.0690 ± 0.0207, p-value: 0.000001, balance: 50]
icache-misses [delta: -5534468 ± 2779620, delta(%): -0.4331 ± 0.2175, p-value: 0.028014, balance: -28]
branch-misses [delta: -1624270 ± 1113244, delta(%): -0.3456 ± 0.2368, p-value: 0.030300, balance: -22]
```

Reviewed By: rafauler

Differential Revision: https://reviews.llvm.org/D120177

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[BOLT][NFC] Fix compiler warnings

Summary:
- variable 'TotalSize' set but not used
- variable 'TotalCallsTopN' set but not used
- use of bitwise '|' with boolean operands

Reviewed By: maksfb

FBD33

[BOLT][NFC] Fix compiler warnings

Summary:
- variable 'TotalSize' set but not used
- variable 'TotalCallsTopN' set but not used
- use of bitwise '|' with boolean operands

Reviewed By: maksfb

FBD33911129

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[BOLT][NFC] Refactor command line options in BinaryPassManager

Summary:
Reformat code and put options in lexicographical order.

Comparing to clang-format output, manual formatting looks cleaner to

[BOLT][NFC] Refactor command line options in BinaryPassManager

Summary:
Reformat code and put options in lexicographical order.

Comparing to clang-format output, manual formatting looks cleaner to me.

(cherry picked from FBD33481692)

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[BOLTRewrite][NFC] Fix braces usages

Summary:
Refactor bolt/*/Rewrite to follow the braces rule for if/else/loop from
LLVM Coding Standards.

(cherry picked from FBD33305364)

[BOLT][NFC] Fix file-description comments

Summary: Fix comments at the start of source files.

(cherry picked from FBD33274597)

[BOLT] Fix profile and tests for nop-removal pass

Summary:
Since nops are now removed in a separate pass, the profile is consumed
on a CFG with nops. If previously a profile was generated without no

[BOLT] Fix profile and tests for nop-removal pass

Summary:
Since nops are now removed in a separate pass, the profile is consumed
on a CFG with nops. If previously a profile was generated without nops,
the offsets in the profile could be different if branches included nops
either as a source or a destination.

This diff adjust offsets to make the profile reading backwards
compatible.

(cherry picked from FBD33231254)

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[BOLT] Move disassemble optimizations to optimization passes

Summary:
The patch moves the shortenInstructions and nop remove to separate binary
passes. As a result when llvm-bolt optimizations stage

[BOLT] Move disassemble optimizations to optimization passes

Summary:
The patch moves the shortenInstructions and nop remove to separate binary
passes. As a result when llvm-bolt optimizations stage will begin the
instructions of the binary functions will be absolutely the same as it
was in the binary. This is needed for the golang support by llvm-bolt.
Some of the tests must be changed, since bb alignment nops might create
unreachable BBs in original functions.

Vladislav Khmelevsky,
Advanced Software Technology Lab, Huawei

(cherry picked from FBD32896517)

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[BOLT][NFC] Reformat with clang-format

Summary: Selectively apply clang-format to BOLT code base.

(cherry picked from FBD33119052)

[BOLT] Add pass to normalize CFG

Summary:
Some optimizations may remove all instructions in a basic block.

The pass will cleanup the CFG afterwards by removing empty basic
blocks and merging duplic

[BOLT] Add pass to normalize CFG

Summary:
Some optimizations may remove all instructions in a basic block.

The pass will cleanup the CFG afterwards by removing empty basic
blocks and merging duplicate CFG edges.

The normalized CFG is printed under '-print-normalized' option.

(cherry picked from FBD32774360)

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Rebase: [BOLT] AsmDump: dump function assembly and profile info

Summary:
Added new functionality of dumping simple functions into assembly.
This includes:
- function control flow (basic blocks, inst

Rebase: [BOLT] AsmDump: dump function assembly and profile info

Summary:
Added new functionality of dumping simple functions into assembly.
This includes:
- function control flow (basic blocks, instructions),
- profile information as `FDATA` directives, to be consumed by link_fdata,
- data labels,
- CFI directives,
- symbols for callee functions,
- jump table symbols.

Envisioned usage:
1. Find a function that triggers BOLT crash (e.g. with `bughunter.sh`).
2. Generate reproducer asm source for that function (using `-funcs`).
3. Attach it to an issue.
4. Reduce and include as a test case.

Current limitations:
1. Emitted assembly won't match input file relocations.
2. No DWARF support.
3. Data is not emitted.

(cherry picked from FBD32746857)

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Rebase: [NFC] Refactor sources to be buildable in shared mode

Summary:
Moves source files into separate components, and make explicit
component dependency on each other, so LLVM build system knows h

Rebase: [NFC] Refactor sources to be buildable in shared mode

Summary:
Moves source files into separate components, and make explicit
component dependency on each other, so LLVM build system knows how to
build BOLT in BUILD_SHARED_LIBS=ON.

Please use the -c merge.renamelimit=230 git option when rebasing your
work on top of this change.

To achieve this, we create a new library to hold core IR files (most
classes beginning with Binary in their names), a new library to hold
Utils, some command line options shared across both RewriteInstance
and core IR files, a new library called Rewrite to hold most classes
concerned with running top-level functions coordinating the binary
rewriting process, and a new library called Profile to hold classes
dealing with profile reading and writing.

To remove the dependency from BinaryContext into X86-specific classes,
we do some refactoring on the BinaryContext constructor to receive a
reference to the specific backend directly from RewriteInstance. Then,
the dependency on X86 or AArch64-specific classes is transfered to the
Rewrite library. We can't have the Core library depend on targets
because targets depend on Core (which would create a cycle).

Files implementing the entry point of a tool are transferred to the
tools/ folder. All header files are transferred to the include/
folder. The src/ folder was renamed to lib/.

(cherry picked from FBD32746834)

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