[AsmPrinter][ELF] Support profile-guided section prefix for jump tables' (read-only) data sections (#122215)

https://github.com/llvm/llvm-project/pull/122183 adds a codegen pass to
infer machine jum

[AsmPrinter][ELF] Support profile-guided section prefix for jump tables' (read-only) data sections (#122215)

https://github.com/llvm/llvm-project/pull/122183 adds a codegen pass to
infer machine jump table entry's hotness from the MBB hotness. This is a
follow-up PR to produce `.hot` and or `.unlikely` section prefix for
jump table's (read-only) data sections in the relocatable `.o` files.

When this patch is enabled, linker will see {`.rodata`, `.rodata.hot`,
`.rodata.unlikely`} in input sections. It can map `.rodata.hot` and
`.rodata` in the input sections to `.rodata.hot` in the executable, and
map `.rodata.unlikely` into `.rodata` with a pending extension to
`--keep-text-section-prefix` like
https://github.com/llvm/llvm-project/commit/059e7cbb66a30ce35f3ee43197eed1a106b50c5b,
or with a linker script.

1. To partition hot and jump tables, the AsmPrinter pass slices a function's jump table indices into two groups, one for hot and the other for cold jump tables. It then emits hot jump tables into a `.hot`-prefixed data section and cold ones into a `.unlikely`-prefixed data section, retaining the relative order of `LJT<N>` labels within each group.

2. [ELF only] To have data sections with _dynamic_ names (e.g., `.rodata.hot[.func]`), we implement
`TargetLoweringObjectFile::getSectionForJumpTable` method that accepts a `MachineJumpTableEntry` parameter, and update `selectELFSectionForGlobal` to generate `.hot` or `.unlikely` based on
MJTE's hotness.
- The dynamic JT section name doesn't depend on `-ffunction-section=true` or `-funique-section-names=true`, even though it leverages the similar underlying mechanism to have a MCSection with on-demand name as `-ffunction-section` does.

3. The new code path is off by default.
- Typically, `TargetOptions` conveys clang or LLVM tools' options to code generation passes. To follow the pattern, add option `EnableStaticDataPartitioning` bit in `TargetOptions` and make it
readable through `TargetMachine`.
- To enable the new code path in tools like `llc`, `partition-static-data-sections` option is introduced in
`CodeGen/CommandFlags.h/cpp`.
- A subsequent patch
([draft](https://github.com/llvm/llvm-project/commit/8f36a1374365862b3ca9be5615dd38f02a318c45)) will add a clang option to enable the new code path.

---------

Co-authored-by: Ellis Hoag <ellis.sparky.hoag@gmail.com>

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[PAC][ELF][AArch64] Support signed personality function pointer (#119361)

Re-apply #113148 after revert in #119331

If function pointer signing is enabled, sign personality function
pointer store

[PAC][ELF][AArch64] Support signed personality function pointer (#119361)

Re-apply #113148 after revert in #119331

If function pointer signing is enabled, sign personality function
pointer stored in `.DW.ref.__gxx_personality_v0` section with IA key,
0x7EAD = `ptrauth_string_discriminator("personality")` constant
discriminator and address diversity enabled.

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Revert "[PAC][ELF][AArch64] Support signed personality function pointer" (#119331)

Reverts llvm/llvm-project#113148

See buildbot failure
https://lab.llvm.org/buildbot/#/builders/190/builds/11048

[PAC][ELF][AArch64] Support signed personality function pointer (#113148)

If function pointer signing is enabled, sign personality function
pointer stored in `.DW.ref.__gxx_personality_v0` section

[PAC][ELF][AArch64] Support signed personality function pointer (#113148)

If function pointer signing is enabled, sign personality function
pointer stored in `.DW.ref.__gxx_personality_v0` section with IA key,
0x7EAD = `ptrauth_string_discriminator("personality")` constant
discriminator and address diversity enabled.

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[IR] Add getDataLayout() helpers to Function and GlobalValue (#96919)

Similar to https://github.com/llvm/llvm-project/pull/96902, this adds
`getDataLayout()` helpers to Function and GlobalValue, re

[IR] Add getDataLayout() helpers to Function and GlobalValue (#96919)

Similar to https://github.com/llvm/llvm-project/pull/96902, this adds
`getDataLayout()` helpers to Function and GlobalValue, replacing the
current `getParent()->getDataLayout()` pattern.

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[clang][llvm] Remove "implicit-section-name" attribute (#87906)

D33412/D33413 introduced this to support a clang pragma to set section
names for a symbol depending on if it would be placed in
bss/

[clang][llvm] Remove "implicit-section-name" attribute (#87906)

D33412/D33413 introduced this to support a clang pragma to set section
names for a symbol depending on if it would be placed in
bss/data/rodata/text, which may not be known until the backend. However,
for text we know that only functions will go there, so just directly set
the section in clang instead of going through a completely separate
attribute.

Autoupgrade the "implicit-section-name" attribute to directly setting
the section on a Fuction.

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[llvm] Qualify auto in range-based for loops (NFC)

Identified with readability-qualified-auto.

[Metadata] Add 'exclude' metadata to add the exclude flags on globals

This patchs adds a new metadata kind `exclude` which implies that the
global variable should be given the necessary flags during

[Metadata] Add 'exclude' metadata to add the exclude flags on globals

This patchs adds a new metadata kind `exclude` which implies that the
global variable should be given the necessary flags during code
generation to not be included in the final executable. This is done
using the ``SHF_EXCLUDE`` flag on ELF for example. This should make it
easier to specify this flag on a variable without needing to explicitly
check the section name in the target backend.

Depends on D129053 D129052

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D129151

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Cleanup includes: LLVMTarget

Most notably, Pass.h is no longer included by TargetMachine.h
before: 1063570306
after: 1063332844

Differential Revision: https://reviews.llvm.org/D121168

[MC] Untangle MCContext and MCObjectFileInfo

This untangles the MCContext and the MCObjectFileInfo. There is a circular
dependency between MCContext and MCObjectFileInfo. Currently this dependency
a

[MC] Untangle MCContext and MCObjectFileInfo

This untangles the MCContext and the MCObjectFileInfo. There is a circular
dependency between MCContext and MCObjectFileInfo. Currently this dependency
also exists during construction: You can't contruct a MOFI without a MCContext
without constructing the MCContext with a dummy version of that MOFI first.
This removes this dependency during construction. In a perfect world,
MCObjectFileInfo wouldn't depend on MCContext at all, but only be stored in the
MCContext, like other MC information. This is future work.

This also shifts/adds more information to the MCContext making it more
available to the different targets. Namely:

- TargetTriple
- ObjectFileType
- SubtargetInfo

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D101462

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[AIX][TLS] Generate TLS variables in assembly files

This patch allows generating TLS variables in assembly files on AIX.
Initialized and external uninitialized variables are generated with the
.csec

[AIX][TLS] Generate TLS variables in assembly files

This patch allows generating TLS variables in assembly files on AIX.
Initialized and external uninitialized variables are generated with the
.csect pseudo-op and local uninitialized variables are generated with
the .comm/.lcomm pseudo-ops. The patch also adds a check to
explicitly say that TLS is not yet supported on AIX.

Reviewed by: daltenty, jasonliu, lei, nemanjai, sfertile
Originally patched by: bsaleil
Commandeered by: NeHuang

Differential Revision: https://reviews.llvm.org/D96184

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[llvm][IR] Do not place constants with static relocations in a mergeable section

This patch provides two major changes:

1. Add getRelocationInfo to check if a constant will have static, dynamic, or

[llvm][IR] Do not place constants with static relocations in a mergeable section

This patch provides two major changes:

1. Add getRelocationInfo to check if a constant will have static, dynamic, or
no relocations. (Also rename the original needsRelocation to needsDynamicRelocation.)
2. Only allow a constant with no relocations (static or dynamic) to be placed
in a mergeable section.

This will allow unused symbols that contain static relocations and happen to
fit in mergeable constant sections (.rodata.cstN) to instead be placed in
unique-named sections if -fdata-sections is used and subsequently garbage collected
by --gc-sections.

See https://lists.llvm.org/pipermail/llvm-dev/2021-February/148281.html.

Differential Revision: https://reviews.llvm.org/D95960

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Basic block sections should enable function sections implicitly.

Basic block sections enables function sections implicitly, this is not needed
and is inefficient with "=list" option.

We had basic b

Basic block sections should enable function sections implicitly.

Basic block sections enables function sections implicitly, this is not needed
and is inefficient with "=list" option.

We had basic block sections enable function sections implicitly in clang. This
is particularly inefficient with "=list" option as it places functions that do
not have any basic block sections in separate sections. This causes unnecessary
object file overhead for large applications.

This patch disables this implicit behavior. It only creates function sections
for those functions that require basic block sections.

Further, there was an inconistent behavior with llc as llc was not turning on
function sections by default. This patch makes llc and clang consistent and
tests are added to check the new behavior.

This is the first of two patches and this adds functionality in LLVM to
create a new section for the entry block if function sections is not
enabled.

Differential Revision: https://reviews.llvm.org/D93876

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[NFC] cleanup cg-profile emission on TargetLowerinng

Differential Revision: https://reviews.llvm.org/D93150

[XCOFF][AIX] Alternative path in EHStreamer for platforms do not have uleb128 support

Summary:
Not all system assembler supports `.uleb128 label2 - label1` form.
When the target do not support this

[XCOFF][AIX] Alternative path in EHStreamer for platforms do not have uleb128 support

Summary:
Not all system assembler supports `.uleb128 label2 - label1` form.
When the target do not support this form, we have to take
alternative manual calculation to get the offsets from them.

Reviewed By: hubert.reinterpretcast

Diffierential Revision: https://reviews.llvm.org/D92058

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Revert "Reland [CodeGen] emit CG profile for COFF object file"

This reverts commit 506b6170cb513f1cb6e93a3b690c758f9ded18ac.

This still causes link errors, see https://crbug.com/1130780.

Reland [CodeGen] emit CG profile for COFF object file

This reverts commit 90242caca2074dab5a9b76e5bc36d9fafd2179a7.

Error fixed at f5435399e823746bbe1737b95c853d77a42e1ac3

Differential Revision: h

Reland [CodeGen] emit CG profile for COFF object file

This reverts commit 90242caca2074dab5a9b76e5bc36d9fafd2179a7.

Error fixed at f5435399e823746bbe1737b95c853d77a42e1ac3

Differential Revision: https://reviews.llvm.org/D87811

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Revert "[CodeGen] emit CG profile for COFF object file"

This reverts commit 91aed9bf975f1e4346cc8f4bdefc98436386ced2, it is
causing link errors.

[CodeGen] emit CG profile for COFF object file

I forgot to add emission of CG profile for COFF object file, when adding the support (https://reviews.llvm.org/D81775)

Differential Revision: https://

[CodeGen] emit CG profile for COFF object file

I forgot to add emission of CG profile for COFF object file, when adding the support (https://reviews.llvm.org/D81775)

Differential Revision: https://reviews.llvm.org/D87811

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[AIX] Emit AvailableExternally Linkage on AIX

Since on AIX, our strategy is to not use -u to suppress any undefined
symbols, we need to emit .extern for the symbols with AvailableExternally
linkage.

[AIX] Emit AvailableExternally Linkage on AIX

Since on AIX, our strategy is to not use -u to suppress any undefined
symbols, we need to emit .extern for the symbols with AvailableExternally
linkage.

Differential Revision: https://reviews.llvm.org/D80642

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[Target] Use Align in TargetLoweringObjectFile::getSectionForConstant.

Differential Revision: https://reviews.llvm.org/D80363

TargetLoweringObjectFile.h - remove unnecessary includes. NFCI.

Replace with forward declarations and move includes down to source files where required.

I also needed to move the TargetLoweringObje

TargetLoweringObjectFile.h - remove unnecessary includes. NFCI.

Replace with forward declarations and move includes down to source files where required.

I also needed to move the TargetLoweringObjectFile::SectionForGlobal wrapper implementation down into TargetLoweringObjectFile.cpp

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Extend BasicBlock sections to allow specifying clusters of basic blocks in the same section.

Differential Revision: https://reviews.llvm.org/D76954

Revert "Extend BasicBlock sections to allow specifying clusters of basic blocks"

This reverts commit 0d4ec16d3db3a92514e14101f635e8536c208c4f Because
tests were not added to the commit.

Extend BasicBlock sections to allow specifying clusters of basic blocks
in the same section.

This allows specifying BasicBlock clusters like the following example:
!foo
!!0 1 2
!!4
This places basic

Extend BasicBlock sections to allow specifying clusters of basic blocks
in the same section.

This allows specifying BasicBlock clusters like the following example:
!foo
!!0 1 2
!!4
This places basic blocks 0, 1, and 2 in one section in this order, and
places basic block #4 in a single section of its own.

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