[MC][ELF] Put explicit section name symbols into entry size compatible sections

Ensure that symbols explicitly* assigned a section name are placed into
a section with a compatible entry size.

This

[MC][ELF] Put explicit section name symbols into entry size compatible sections

Ensure that symbols explicitly* assigned a section name are placed into
a section with a compatible entry size.

This is done by creating multiple sections with the same name** if
incompatible symbols are explicitly given the name of an incompatible
section, whilst:

- Avoiding using uniqued sections where possible (for readability and
to maximize compatibly with assemblers).

- Creating as few SHF_MERGE sections as possible (for efficiency).

Given that each symbol is assigned to a section in a single pass, we
must decide which section each symbol is assigned to without seeing the
properties of all symbols. A stable and easy to understand assignment is
desirable. The following rules facilitate this: The "generic" section
for a given section name will be mergeable if the name is a mergeable
"default" section name (such as .debug_str), a mergeable "implicit"
section name (such as .rodata.str2.2), or MC has already created a
mergeable "generic" section for the given section name (e.g. in response
to a section directive in inline assembly). Otherwise, the "generic"
section for a given name is non-mergeable; and, non-mergeable symbols
are assigned to the "generic" section, while mergeable symbols are
assigned to uniqued sections.

Terminology:
"default" sections are those always created by MC initially, e.g. .text
or .debug_str.

"implicit" sections are those created normally by MC in response to the
symbols that it encounters, i.e. in the absence of an explicit section
name assignment on the symbol, e.g. a function foo might be placed into
a .text.foo section.

"generic" sections are those that are referred to when a unique section
ID is not supplied, e.g. if there are multiple unique .bob sections then
".quad .bob" will reference the generic .bob section. Typically, the
generic section is just the first section of a given name to be created.
Default sections are always generic.

* Typically, section names might be explicitly assigned in source code
using a language extension e.g. a section attribute: _attribute_
((section ("section-name"))) -
https://clang.llvm.org/docs/AttributeReference.html

** I refer to such sections as unique/uniqued sections. In assembly the
", unique," assembly syntax is used to express such sections.

Fixes https://bugs.llvm.org/show_bug.cgi?id=43457.

See https://reviews.llvm.org/D68101 for previous discussions leading to
this patch.

Some minor fixes were required to LLVM's tests, for tests had been using
the old behavior - which allowed for explicitly assigning globals with
incompatible entry sizes to a section.

This fix relies on the ",unique ," assembly feature. This feature is not
available until bintuils version 2.35
(https://sourceware.org/bugzilla/show_bug.cgi?id=25380). If the
integrated assembler is not being used then we avoid using this feature
for compatibility and instead try to place mergeable symbols into
non-mergeable sections or issue an error otherwise.

Differential Revision: https://reviews.llvm.org/D72194

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[MC] Rename MCSection*::getSectionName() to getName(). NFC

A pending change will merge MCSection*::getName() to MCSection::getName().

[NFC] correct "thier" to "their"

[WebAssembly] Emit .llvmcmd and .llvmbc as custom sections

Fixes: https://bugs.llvm.org/show_bug.cgi?id=45362

Differential Revision: https://reviews.llvm.org/D77115

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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Clean up usages of asserting vector getters in Type

Summary:
Remove usages of asserting vector getters in Type in preparation for the
VectorType refactor. The existence of these functions complicate

Clean up usages of asserting vector getters in Type

Summary:
Remove usages of asserting vector getters in Type in preparation for the
VectorType refactor. The existence of these functions complicates the
refactor while adding little value.

Reviewers: stoklund, sdesmalen, efriedma

Reviewed By: sdesmalen

Subscribers: hiraditya, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D77272

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[AIX] discard the label in the csect of function description and use qualname for linkage

SUMMARY:

SUMMARY
for a source file "test.c"

void foo() {};

llc will generate assembly code as (assembly

[AIX] discard the label in the csect of function description and use qualname for linkage

SUMMARY:

SUMMARY
for a source file "test.c"

void foo() {};

llc will generate assembly code as (assembly patch)
.globl foo
.globl .foo
.csect foo[DS]
foo:

.long .foo
.long TOC[TC0]
.long 0

and symbol table as (xcoff object file)
[4] m 0x00000004 .data 1 unamex foo
[5] a4 0x0000000c 0 0 SD DS 0 0
[6] m 0x00000004 .data 1 extern foo
[7] a4 0x00000004 0 0 LD DS 0 0

After first patch, the assembly will be as

.globl foo[DS] # -- Begin function foo
.globl .foo
.align 2
.csect foo[DS]
.long .foo
.long TOC[TC0]
.long 0

and symbol table will as
[6] m 0x00000004 .data 1 extern foo
[7] a4 0x00000004 0 0 DS DS 0 0
Change the code for the assembly path and xcoff objectfile patch for llc.

Reviewers: Jason Liu
Subscribers: wuzish, nemanjai, hiraditya

Differential Revision: https://reviews.llvm.org/D76162

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[X86] Reland D71360 Clean up UseInitArray initialization for X86ELFTargetObjectFile

-fuse-init-array is now the CC1 default but TargetLoweringObjectFileELF::UseInitArray still defaults to false.
The

[X86] Reland D71360 Clean up UseInitArray initialization for X86ELFTargetObjectFile

-fuse-init-array is now the CC1 default but TargetLoweringObjectFileELF::UseInitArray still defaults to false.
The following two unknown OS target triples continue using .ctors/.dtors because InitializeELF is not called.

clang -target i386 -c a.c
clang -target x86_64 -c a.c

This cleanup fixes this as a bonus.

X86SpeculativeLoadHardeningPass::tracePredStateThroughCall can call
MCContext::createTempSymbol before TargetLoweringObjectFileELF::Initialize().
We need to call TargetLoweringObjectFileELF::Initialize() ealier.

test/CodeGen/X86/speculative-load-hardening-indirect.ll

Differential Revision: https://reviews.llvm.org/D71360

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Temporarily Revert "[X86] Reland D71360 Clean up UseInitArray initialization for X86ELFTargetObjectFile"
as it's causing msan failures.

This reverts commit 7899fe9da8d8df6f19ddcbbb877ea124d711c54b.

[X86] Reland D71360 Clean up UseInitArray initialization for X86ELFTargetObjectFile

UseInitArray is now the CC1 default but TargetLoweringObjectFileELF::UseInitArray still defaults to false.
The fol

[X86] Reland D71360 Clean up UseInitArray initialization for X86ELFTargetObjectFile

UseInitArray is now the CC1 default but TargetLoweringObjectFileELF::UseInitArray still defaults to false.
The following two unknown OS target triples continue using .ctors/.dtors because InitializeELF is not called.

clang -target i386 -c a.c
clang -target x86_64 -c a.c

This cleanup fixes this as a bonus.

Differential Revision: https://reviews.llvm.org/D71360

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Basic Block Sections support in LLVM.

This is the second patch in a series of patches to enable basic block
sections support.

This patch adds support for:

* Creating direct jumps at the end of bas

Basic Block Sections support in LLVM.

This is the second patch in a series of patches to enable basic block
sections support.

This patch adds support for:

* Creating direct jumps at the end of basic blocks that have fall
through instructions.
* New pass, bbsections-prepare, that analyzes placement of basic blocks
in sections.
* Actual placing of a basic block in a unique section with special
handling of exception handling blocks.
* Supports placing a subset of basic blocks in a unique section.
* Support for MIR serialization and deserialization with basic block
sections.

Parent patch : D68063
Differential Revision: https://reviews.llvm.org/D73674

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Fix conflict value for metadata "Objective-C Garbage Collection" in the mix of swift and Objective-C bitcode

Summary:
The change is to fix conflict value for metadata "Objective-C Garbage Collection

Fix conflict value for metadata "Objective-C Garbage Collection" in the mix of swift and Objective-C bitcode

Summary:
The change is to fix conflict value for metadata "Objective-C Garbage Collection" in the mix of swift and Objective-C bitcode.
The purpose is to provide the support of LTO for swift and Objective-C mixed project.

Reviewers: rjmccall, ahatanak, steven_wu

Reviewed By: rjmccall, steven_wu

Subscribers: manmanren, mehdi_amini, hiraditya, dexonsmith, llvm-commits, jinlin

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71219

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[AIX] Handle LinkOnceODRLinkage and AppendingLinkage for static init gloabl arrays

Handle LinkOnceODRLinkage;
Handle AppendingLinkage type for llvm.global_ctors/dtors static init global arrays;

Dif

[AIX] Handle LinkOnceODRLinkage and AppendingLinkage for static init gloabl arrays

Handle LinkOnceODRLinkage;
Handle AppendingLinkage type for llvm.global_ctors/dtors static init global arrays;

Differential Revision: https://reviews.llvm.org/D75305

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[MC] Add MCStreamer::emitInt{8,16,32,64}

Similar to AsmPrinter::emitInt{8,16,32,64}.

Reland: [Coverage] Revise format to reduce binary size

Try again with an up-to-date version of D69471 (99317124 was a stale
revision).

---

Revise the coverage mapping format to reduce binary size

Reland: [Coverage] Revise format to reduce binary size

Try again with an up-to-date version of D69471 (99317124 was a stale
revision).

---

Revise the coverage mapping format to reduce binary size by:

1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.

This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).

Rationale for changes to the format:

- With the current format, most coverage function records are discarded.
E.g., more than 97% of the records in llc are *duplicate* placeholders
for functions visible-but-not-used in TUs. Placeholders *are* used to
show under-covered functions, but duplicate placeholders waste space.

- We reached general consensus about giving (1) a try at the 2017 code
coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
duplicates is simpler than alternatives like teaching build systems
about a coverage-aware database/module/etc on the side.

- Revising the format is expensive due to the backwards compatibility
requirement, so we might as well compress filenames while we're at it.
This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).

See CoverageMappingFormat.rst for the details on what exactly has
changed.

Fixes PR34533 [2], hopefully.

[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533

Differential Revision: https://reviews.llvm.org/D69471

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Revert "[Coverage] Revise format to reduce binary size"

This reverts commit 99317124e1c772e9a9de41a0cd56e1db049b4ea4. This is
still busted on Windows:

http://lab.llvm.org:8011/builders/lld-x86_64-w

Revert "[Coverage] Revise format to reduce binary size"

This reverts commit 99317124e1c772e9a9de41a0cd56e1db049b4ea4. This is
still busted on Windows:

http://lab.llvm.org:8011/builders/lld-x86_64-win7/builds/40873

The llvm-cov tests report 'error: Could not load coverage information'.

show more ...

[Coverage] Revise format to reduce binary size

Revise the coverage mapping format to reduce binary size by:

1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.

[Coverage] Revise format to reduce binary size

Revise the coverage mapping format to reduce binary size by:

1. Naming function records and marking them `linkonce_odr`, and
2. Compressing filenames.

This shrinks the size of llc's coverage segment by 82% (334MB -> 62MB)
and speeds up end-to-end single-threaded report generation by 10%. For
reference the compressed name data in llc is 81MB (__llvm_prf_names).

Rationale for changes to the format:

- With the current format, most coverage function records are discarded.
E.g., more than 97% of the records in llc are *duplicate* placeholders
for functions visible-but-not-used in TUs. Placeholders *are* used to
show under-covered functions, but duplicate placeholders waste space.

- We reached general consensus about giving (1) a try at the 2017 code
coverage BoF [1]. The thinking was that using `linkonce_odr` to merge
duplicates is simpler than alternatives like teaching build systems
about a coverage-aware database/module/etc on the side.

- Revising the format is expensive due to the backwards compatibility
requirement, so we might as well compress filenames while we're at it.
This shrinks the encoded filenames in llc by 86% (12MB -> 1.6MB).

See CoverageMappingFormat.rst for the details on what exactly has
changed.

Fixes PR34533 [2], hopefully.

[1] http://lists.llvm.org/pipermail/llvm-dev/2017-October/118428.html
[2] https://bugs.llvm.org/show_bug.cgi?id=34533

Differential Revision: https://reviews.llvm.org/D69471

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[WebAssembly] Remove unneeded getWasmKindForNamedSection function

I believe this was carried over from getELFKindForNamedSection since
the wasm backend originally used ELF object writing as a templa

[WebAssembly] Remove unneeded getWasmKindForNamedSection function

I believe this was carried over from getELFKindForNamedSection since
the wasm backend originally used ELF object writing as a template.

Differential Revision: https://reviews.llvm.org/D74565

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[MCStreamer] De-capitalize EmitValue EmitIntValue{,InHex}

[MC] De-capitalize another set of MCStreamer::Emit* functions

Emit{ValueTo,Code}Alignment Emit{DTP,TP,GP}* EmitSymbolValue etc

[MC] De-capitalize some MCStreamer::Emit* functions

[AIX][XCOFF] Support Mergeable2ByteCString and Mergeable4ByteCString

SUMMARY:
The patch is enable to support Mergeable2ByteCString and Mergeable4ByteCString

Reviewers: daltenty
Subscribers: wuzish,

[AIX][XCOFF] Support Mergeable2ByteCString and Mergeable4ByteCString

SUMMARY:
The patch is enable to support Mergeable2ByteCString and Mergeable4ByteCString

Reviewers: daltenty
Subscribers: wuzish, nemanjai, hiraditya

Differential Revision: https://reviews.llvm.org/D74164

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[MC][ELF] Rename MC related "Associated" to "LinkedToSym"

"linked-to section" is used by the ELF spec. By analogy, "linked-to
symbol" is a good name for the signature symbol. The word "linked-to"
i

[MC][ELF] Rename MC related "Associated" to "LinkedToSym"

"linked-to section" is used by the ELF spec. By analogy, "linked-to
symbol" is a good name for the signature symbol. The word "linked-to"
implies a directed edge and makes it clear its relation with "sh_link",
while one can argue that "associated" means an undirected edge.

Also, combine tests and add precise SMLoc to improve diagnostics.

Reviewed By: eugenis, grimar, jhenderson

Differential Revision: https://reviews.llvm.org/D74082

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