Rework the `Option` library to reduce dynamic relocations (#119198)

Apologies for the large change, I looked for ways to break this up and
all of the ones I saw added real complexity. This change f

Rework the `Option` library to reduce dynamic relocations (#119198)

Apologies for the large change, I looked for ways to break this up and
all of the ones I saw added real complexity. This change focuses on the
option's prefixed names and the array of prefixes. These are present in
every option and the dominant source of dynamic relocations for PIE or
PIC users of LLVM and Clang tooling. In some cases, 100s or 1000s of
them for the Clang driver which has a huge number of options.

This PR addresses this by building a string table and a prefixes table
that can be referenced with indices rather than pointers that require
dynamic relocations. This removes almost 7k dynmaic relocations from the
`clang` binary, roughly 8% of the remaining dynmaic relocations outside
of vtables. For busy-boxing use cases where many different option tables
are linked into the same binary, the savings add up a bit more.

The string table is a straightforward mechanism, but the prefixes
required some subtlety. They are encoded in a Pascal-string fashion with
a size followed by a sequence of offsets. This works relatively well for
the small realistic prefixes arrays in use.

Lots of code has to change in order to land this though: both all the
option library code has to be updated to use the string table and
prefixes table, and all the users of the options library have to be
updated to correctly instantiate the objects.

Some follow-up patches in the works to provide an abstraction for this
style of code, and to start using the same technique for some of the
other strings here now that the infrastructure is in place.

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[SystemZ][z/OS] Open text files in text mode (#109972)

This patch continues the work that was started here
https://reviews.llvm.org/D99426 to correctly open text files in text
mode.

Reapply "[Option] Add "Visibility" field and clone the OptTable APIs to use it"

This reverts commit 4e3b89483a6922d3f48670bb1c50a37f342918c6, with
fixes for places I'd missed updating in lld and lld

Reapply "[Option] Add "Visibility" field and clone the OptTable APIs to use it"

This reverts commit 4e3b89483a6922d3f48670bb1c50a37f342918c6, with
fixes for places I'd missed updating in lld and lldb. I've also
renamed OptionVisibility::Default to "DefaultVis" to avoid ambiguity
since the undecorated name has to be available anywhere Options.inc is
included.

Original message follows:

This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and adds
variants of the OptTable APIs that use Visibility mask instead of
Include/Exclude flags.

We need to do this to clean up a bunch of complexity in the clang
driver's option handling - there's a whole slew of flags like
CoreOption, NoDriverOption, and FlangOnlyOption there today to try to
handle all of the permutations of flags that the various drivers need,
but it really doesn't scale well, as can be seen by things like the
somewhat recently introduced CLDXCOption.

Instead, we'll provide an additive model for visibility that's
separate from the other flags. For things like "HelpHidden", which is
used as a "subtractive" modifier for option visibility, we leave that
in "Flags" and handle it as a special case.

Note that we don't actually update the users of the Include/Exclude
APIs here or change the flags that exist in clang at all - that will
come in a follow up that refactors clang's Options.td to use the
increased flexibility this change allows.

Differential Revision: https://reviews.llvm.org/D157149

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Revert "[Option] Add "Visibility" field and clone the OptTable APIs to use it"

this is failing on bots, reverting to investigate.

This reverts commit a16104e6da6f36f3d72dbf53d10ba56495a0d65a.

[Option] Add "Visibility" field and clone the OptTable APIs to use it

This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and a

[Option] Add "Visibility" field and clone the OptTable APIs to use it

This splits OptTable's "Flags" field into "Flags" and "Visibility",
updates the places where we instantiate Option tables, and adds
variants of the OptTable APIs that use Visibility mask instead of
Include/Exclude flags.

We need to do this to clean up a bunch of complexity in the clang
driver's option handling - there's a whole slew of flags like
CoreOption, NoDriverOption, and FlangOnlyOption there today to try to
handle all of the permutations of flags that the various drivers need,
but it really doesn't scale well, as can be seen by things like the
somewhat recently introduced CLDXCOption.

Instead, we'll provide an additive model for visibility that's
separate from the other flags. For things like "HelpHidden", which is
used as a "subtractive" modifier for option visibility, we leave that
in "Flags" and handle it as a special case.

Note that we don't actually update the users of the Include/Exclude
APIs here or change the flags that exist in clang at all - that will
come in a follow up that refactors clang's Options.td to use the
increased flexibility this change allows.

Differential Revision: https://reviews.llvm.org/D157149

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[llvm] Extract common `OptTable` bits into macros

All command-line tools using `llvm::opt` create an enum of option IDs and a table of `OptTable::Info` object. Most of the tools use the same ID (`OP

[llvm] Extract common `OptTable` bits into macros

All command-line tools using `llvm::opt` create an enum of option IDs and a table of `OptTable::Info` object. Most of the tools use the same ID (`OPT_##ID`), kind (`Option::KIND##Class`), group ID (`OPT_##GROUP`) and alias ID (`OPT_##ALIAS`). This patch extracts that common code into canonical macros. This results in fewer changes when tweaking the `OPTION` macros emitted by the TableGen backend.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D157028

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[llvm] Add missing StringExtras.h includes

In preparation for removing the `#include "llvm/ADT/StringExtras.h"`
from the header to source file of `llvm/Support/Error.h`, first add in
all the missing

[llvm] Add missing StringExtras.h includes

In preparation for removing the `#include "llvm/ADT/StringExtras.h"`
from the header to source file of `llvm/Support/Error.h`, first add in
all the missing includes that were previously included transitively
through this header.

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[Option] Support special argument "--"

Many command line option implementations, including getopt_long and our
Support/CommandLine.cpp, support `--` as an end-of-option indicator. All
the subsequent

[Option] Support special argument "--"

Many command line option implementations, including getopt_long and our
Support/CommandLine.cpp, support `--` as an end-of-option indicator. All
the subsequent arguments are then treated as positional arguments.

D1387 added KIND_REMAINING_ARGS and 76ff1d915c9c42823a3f2b08ff936cf7a48933c5 dropped special handling of `--`.
Users need to add `def DASH_DASH : Option<["--"], "", KIND_REMAINING_ARGS>;` and
append `OPT_DASH_DASH` to the `OPT_INPUT` list., which is not ergonomic.

Restore this feature under an option and modify llvm-strings to utilize the
feature as an example. In the future, we probably should enable this feature by
default and exclude some tools that handle `DASH_DASH` differently (clang,
clang-scan-deps, etc. I suspect that many are workarounds for LLVMOption not
supporting `--` as a built-in feature).

Reviewed By: serge-sans-paille

Differential Revision: https://reviews.llvm.org/D152286

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[OptTable] Precompute OptTable prefixes union table through tablegen

This avoid rediscovering this table when reading each options, providing
a sensible 2% speedup when processing and empty file, an

[OptTable] Precompute OptTable prefixes union table through tablegen

This avoid rediscovering this table when reading each options, providing
a sensible 2% speedup when processing and empty file, and a measurable
speedup on typical workloads, see:

This is optional, the legacy, on-the-fly, approach can still be used
through the GenericOptTable class, while the new one is used through
PrecomputedOptTable.

https://llvm-compile-time-tracker.com/compare.php?from=4da6cb3202817ee2897d6b690e4af950459caea4&to=19a492b704e8f5c1dea120b9c0d3859bd78796be&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D140800

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[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

This a recommit of e953ae5bbc313fd0cc980ce021d487e5b5199ea4 and the subsequent fixes caa713559bd38f337d7d35de35686775e8fb5175 and 06b90e2e9c991e211fecc97948e533320a825470.

The above patchset caused some version of GCC to take eons to compile clang/lib/Basic/Targets/AArch64.cpp, as spotted in aa171833ab0017d9732e82b8682c9848ab25ff9e.
The fix is to make BuiltinInfo tables a compilation unit static variable, instead of a private static variable.

Differential Revision: https://reviews.llvm.org/D139881

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Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"
Revert "Fix lldb option handling since e953ae5bbc313fd0cc980ce021d487e5b5199ea4 (part 2)"
Revert "

Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"
Revert "Fix lldb option handling since e953ae5bbc313fd0cc980ce021d487e5b5199ea4 (part 2)"
Revert "Fix lldb option handling since e953ae5bbc313fd0cc980ce021d487e5b5199ea4"

GCC build hangs on this bot https://lab.llvm.org/buildbot/#/builders/37/builds/19104
compiling CMakeFiles/obj.clangBasic.dir/Targets/AArch64.cpp.d

The bot uses GNU 11.3.0, but I can reproduce locally with gcc (Debian 12.2.0-3) 12.2.0.

This reverts commit caa713559bd38f337d7d35de35686775e8fb5175.
This reverts commit 06b90e2e9c991e211fecc97948e533320a825470.
This reverts commit e953ae5bbc313fd0cc980ce021d487e5b5199ea4.

show more ...

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

This is a recommit of 719d98dfa841c522d8d452f0685e503538415a53 that into
account a GGC issue (probably
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92181) when dealing with
intiailizer_list and constant expressions.

Workaround this by avoiding initializer list, at the expense of a
temporary plain old array.

Differential Revision: https://reviews.llvm.org/D139881

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Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

There are still remaining issues with GCC 12, see for instance

https://lab.llvm.org/buildbot/#/b

Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

There are still remaining issues with GCC 12, see for instance

https://lab.llvm.org/buildbot/#/builders/93/builds/12669

This reverts commit 5ce4e92264102de21760c94db9166afe8f71fcf6.

show more ...

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

This is a recommit of 719d98dfa841c522d8d452f0685e503538415a53 with a
change to llvm/utils/TableGen/OptParserEmitter.cpp to cope with GCC bug
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108158

Differential Revision: https://reviews.llvm.org/D139881

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Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

Failing builds: https://lab.llvm.org/buildbot#builders/9/builds/19030
This is GCC specific and ha

Revert "[clang] Use a StringRef instead of a raw char pointer to store builtin and call information"

Failing builds: https://lab.llvm.org/buildbot#builders/9/builds/19030
This is GCC specific and has been reported upstream: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108158

This reverts commit 719d98dfa841c522d8d452f0685e503538415a53.

show more ...

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on pr

[clang] Use a StringRef instead of a raw char pointer to store builtin and call information

This avoids recomputing string length that is already known at compile
time.

It has a slight impact on preprocessing / compile time, see

https://llvm-compile-time-tracker.com/compare.php?from=3f36d2d579d8b0e8824d9dd99bfa79f456858f88&to=e49640c507ddc6615b5e503144301c8e41f8f434&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D139881

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Store OptTable::Info::Name as a StringRef

This is a recommit of 8ae18303f97d5dcfaecc90b4d87effb2011ed82e,
with a few cleanups.

This avoids implicit conversion to StringRef at several points, which

Store OptTable::Info::Name as a StringRef

This is a recommit of 8ae18303f97d5dcfaecc90b4d87effb2011ed82e,
with a few cleanups.

This avoids implicit conversion to StringRef at several points, which in
turns avoid redundant calls to strlen.

As a side effect, this greatly simplifies the implementation of
StrCmpOptionNameIgnoreCase.

It also eventually gives a consistent, humble speedup in compilation
time (timing updated since original commit).

https://llvm-compile-time-tracker.com/compare.php?from=de4b6a1bc64db33643f001ad45fae7b92b4a4688&to=c23a93d1292052b4be2fbe8c586fa31143d0c7ed&stat=instructions:u

Differential Revision: https://reviews.llvm.org/D139274

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

[llvm-strings] Remove use of hard coded executable name

Other tools take their tool name from argv[0] for use in output
messages. This change makes llvm-strings consistent with other tools
rather th

[llvm-strings] Remove use of hard coded executable name

Other tools take their tool name from argv[0] for use in output
messages. This change makes llvm-strings consistent with other tools
rather than using a hard coded value.

Differential Revision: https://reviews.llvm.org/D116604

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[tools] Delete redundant 'static' from namespace scope 'static const'. NFC

[llvm] Replace LLVM_ATTRIBUTE_NORETURN with C++11 [[noreturn]]

[[noreturn]] can be used since Oct 2016 when the minimum compiler requirement was bumped to GCC 4.8/MSVC 2015.

Note: the definition of

[llvm] Replace LLVM_ATTRIBUTE_NORETURN with C++11 [[noreturn]]

[[noreturn]] can be used since Oct 2016 when the minimum compiler requirement was bumped to GCC 4.8/MSVC 2015.

Note: the definition of LLVM_ATTRIBUTE_NORETURN is kept for now.

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[llvm-strings] Switch command line parsing from llvm::cl to OptTable

Some behavior changes:

* `-t=d` is removed. Use `-t d` instead.
* one-dash long options like `-all` are supported. Use `--all` i

[llvm-strings] Switch command line parsing from llvm::cl to OptTable

Some behavior changes:

* `-t=d` is removed. Use `-t d` instead.
* one-dash long options like `-all` are supported. Use `--all` instead.
* `--all=0` or `--all=false` cannot be used. (Note: `--all` is silently ignored anyway)
* `--help-list` is removed. This is a `cl::` specific option.

Nobody is likely leveraging any of the above.

Advantages:

* `-t` diagnostic gets improved.
* in the absence of `HideUnrelatedOptions`, `--help` will not list unrelated options if linking against libLLVM-13git.so or linker GC is not used.
* Decrease the probability of cl::opt collision if we do decide to support multiplexing

Note: because the tool is so simple, used more for forensics instead of a building
tool, and its long options are unlikely used in one-dash form, I just drop the
one-dash form in this patch.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D104889

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[binutils] Add response file option to help and docs

Many LLVM-based tools already support response files (i.e. files
containing a list of options, specified with '@'). This change simply
updates th

[binutils] Add response file option to help and docs

Many LLVM-based tools already support response files (i.e. files
containing a list of options, specified with '@'). This change simply
updates the documentation and help text for some of these tools to
include it. I haven't attempted to fix all tools, just a selection that
I am interested in.

I've taken the opportunity to add some tests for --help behaviour, where
they were missing. We could expand these tests, but I don't think that's
within scope of this patch.

This fixes https://bugs.llvm.org/show_bug.cgi?id=42233 and
https://bugs.llvm.org/show_bug.cgi?id=42236.

Reviewed by: grimar, MaskRay, jkorous

Differential Revision: https://reviews.llvm.org/D63597

llvm-svn: 364036

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Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the ne

Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636

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[llvm-strings] Fix whitespaces to match strings output.

Summary:
The current implementation prepends a space on every line, making it difficult to compare against GNU strings.

The space appears to

[llvm-strings] Fix whitespaces to match strings output.

Summary:
The current implementation prepends a space on every line, making it difficult to compare against GNU strings.

The space appears to have come from handling --radix in rL292707. The space is for making sure there's a space between the radix and the value; however the space is still emitted even when there is no radix. This change fixes that so the space is only emitted when there is a radix.

Reviewers: jhenderson

Reviewed By: jhenderson

Subscribers: llvm-commits, compnerd

Differential Revision: https://reviews.llvm.org/D54238

llvm-svn: 346529

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