[CGDebugInfo] Access the current working directory from the `VFS`

...instead of calling `llvm::sys::fs::current_path()` directly.

Differential Revision: https://reviews.llvm.org/D130443

[Clang] Always set opaque pointers mode

Always set the opaque pointers mode, to make sure that
-no-opaque-pointers continues working when the default on the LLVM
side is flipped.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D115907

show more ...

[LLVMContext] Replace enableOpaquePointers() with setOpaquePointers()

This allows both explicitly enabling and explicitly disabling
opaque pointers, in anticipation of the default switching at some

[LLVMContext] Replace enableOpaquePointers() with setOpaquePointers()

This allows both explicitly enabling and explicitly disabling
opaque pointers, in anticipation of the default switching at some
point.

This also slightly changes the rules by allowing calls if either
the opaque pointer mode has not yet been set (explicitly or
implicitly) or if the value remains unchanged.

show more ...

[OpaquePtrs][Clang] Add -opaque-pointers/-no-opaque-pointers cc1 options

This adds cc1 options for enabling and disabling opaque pointers
on the clang side. This is not super useful now (because
-ml

[OpaquePtrs][Clang] Add -opaque-pointers/-no-opaque-pointers cc1 options

This adds cc1 options for enabling and disabling opaque pointers
on the clang side. This is not super useful now (because
-mllvm -opaque-pointers and -Xclang -opaque-pointers have the same
visible effect) but will be important once opaque pointers are
enabled by default in clang. In that case, it will only be
possible to disable them using the cc1 -no-opaque-pointers option.

Differential Revision: https://reviews.llvm.org/D123034

show more ...

Revert "[misexpect] Re-implement MisExpect Diagnostics"

This reverts commit 46774df307159444d65083c2fd82f8574f0ab1d9.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D115907

show more ...

Revert "[misexpect] Re-implement MisExpect Diagnostics"

This reverts commit 2add3fbd976d7b80a3a7fc14ef0deb9b1ca6beee.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Reviewed By: tejohnson

Differential Revision: https://reviews.llvm.org/D115907

show more ...

Revert "Revert "Revert "[misexpect] Re-implement MisExpect Diagnostics"""

This reverts commit 6cf560d69a222bff4af4e1d092437fd77f0f981c.

Revert "Revert "[misexpect] Re-implement MisExpect Diagnostics""

I mistakenly reverted my commit, so I'm relanding it.

This reverts commit 10866a1df4a82cdc54187330c509a2d46235455d.

Revert "[misexpect] Re-implement MisExpect Diagnostics"

This reverts commit e7749d4713a5ec886011ceb0fc821c6723061724.

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks

[misexpect] Re-implement MisExpect Diagnostics

Reimplements MisExpect diagnostics from D66324 to reconstruct its
original checking methodology only using MD_prof branch_weights
metadata.

New checks rely on 2 invariants:

1) For frontend instrumentation, MD_prof branch_weights will always be
populated before llvm.expect intrinsics are lowered.

2) for IR and sample profiling, llvm.expect intrinsics will always be
lowered before branch_weights are populated from the IR profiles.

These invariants allow the checking to assume how the existing branch
weights are populated depending on the profiling method used, and emit
the correct diagnostics. If these invariants are ever invalidated, the
MisExpect related checks would need to be updated, potentially by
re-introducing MD_misexpect metadata, and ensuring it always will be
transformed the same way as branch_weights in other optimization passes.

Frontend based profiling is now enabled without using LLVM Args, by
introducing a new CodeGen option, and checking if the -Wmisexpect flag
has been passed on the command line.

Differential Revision: https://reviews.llvm.org/D115907

show more ...

[clang] Fix CodeGenAction for LLVM IR MemBuffers

Replaces use of getCurrentFile with getCurrentFileOrBufferName
in CodeGenAction. This avoids an assertion error or an incorrect
name chosen for the o

[clang] Fix CodeGenAction for LLVM IR MemBuffers

Replaces use of getCurrentFile with getCurrentFileOrBufferName
in CodeGenAction. This avoids an assertion error or an incorrect
name chosen for the output file when assertions are disabled.
This error previously occurred when the FrontendInputFile was a
MemoryBuffer instead of a file.

Reviewed By: jlebar

Differential Revision: https://reviews.llvm.org/D121259

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[OpenMP] Add a flag for embedding a file into the module

This patch adds support for a flag `-fembed-offload-binary` to embed a
file as an ELF section in the output by placing it in a global variabl

[OpenMP] Add a flag for embedding a file into the module

This patch adds support for a flag `-fembed-offload-binary` to embed a
file as an ELF section in the output by placing it in a global variable.
This can be used to bundle offloading files with the host binary so it
can be accessed by the linker. The section is named using the
`-fembed-offload-section` option.

Depends on D116541

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D116542

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Remove redundant return and continue statements (NFC)

Identified with readability-redundant-control-flow.

[clang] Add option to disable -clear-ast-before-backend

Some downstream users have plugins that -clear-ast-before-backend may
affect. Add an option to opt out.

Reviewed By: dblaikie

Differential R

[clang] Add option to disable -clear-ast-before-backend

Some downstream users have plugins that -clear-ast-before-backend may
affect. Add an option to opt out.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D112100

show more ...

[clang] Support -clear-ast-before-backend without -disable-free

Previously without -disable-free, -clear-ast-before-backend would crash in ~ASTContext() due to various reasons.
This works around tha

[clang] Support -clear-ast-before-backend without -disable-free

Previously without -disable-free, -clear-ast-before-backend would crash in ~ASTContext() due to various reasons.
This works around that by doing a lot of the cleanup ahead of the destructor so that the destructor doesn't actually do any manual cleanup if we've already cleaned up beforehand.

This actually does save a measurable amount of memory with -clear-ast-before-backend, although at an almost unnoticeable runtime cost:
https://llvm-compile-time-tracker.com/compare.php?from=5d755b32f2775b9219f6d6e2feda5e1417dc993b&to=58ef1c7ad7e2ad45f9c97597905a8cf05a26258c&stat=max-rss

Previously we weren't doing any cleanup with -disable-free, so I tried measuring the impact of always doing the cleanup and didn't measure anything noticeable on llvm-compile-time-tracker.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D111767

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[clang] Add option to clear AST memory before running LLVM passes

This is to save memory for Clang compiles.
Measuring building PassBuilder.cpp under /usr/bin/time, max rss goes from 0.93GB to 0.7GB

[clang] Add option to clear AST memory before running LLVM passes

This is to save memory for Clang compiles.
Measuring building PassBuilder.cpp under /usr/bin/time, max rss goes from 0.93GB to 0.7GB.

This does not turn it by default yet.

I've turned on the option locally and run it over a good amount of files without any issues.

For more background, see
https://lists.llvm.org/pipermail/cfe-dev/2021-September/068930.html.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D111105

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[clang] Don't use the AST to display backend diagnostics

We keep a map from function name to source location so we don't have to
do it via looking up a source location from the AST. However, since
f

[clang] Don't use the AST to display backend diagnostics

We keep a map from function name to source location so we don't have to
do it via looking up a source location from the AST. However, since
function names can be long, we actually use a hash of the function name
as the key.

Additionally, we can't rely on Clang's printing of function names via
the AST, so we just demangle the name instead.

This is necessary to implement
https://lists.llvm.org/pipermail/cfe-dev/2021-September/068930.html.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D110665

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Reland [clang] Rework dontcall attributes

To avoid using the AST when emitting diagnostics, split the "dontcall"
attribute into "dontcall-warn" and "dontcall-error", and also add the
frontend attrib

Reland [clang] Rework dontcall attributes

To avoid using the AST when emitting diagnostics, split the "dontcall"
attribute into "dontcall-warn" and "dontcall-error", and also add the
frontend attribute value as the LLVM attribute value. This gives us all
the information to report diagnostics we need from within the IR (aside
from access to the original source).

One downside is we directly use LLVM's demangler rather than using the
existing Clang diagnostic pretty printing of symbols.

Previous revisions didn't properly declare the new dependencies.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D110364

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Revert "[clang] Rework dontcall attributes"

This reverts commit 2943071e2ee0c7f31f34062a44d12aeb0e3a66fd.

Breaks bots

[clang] Rework dontcall attributes

To avoid using the AST when emitting diagnostics, split the "dontcall"
attribute into "dontcall-warn" and "dontcall-error", and also add the
frontend attribute val

[clang] Rework dontcall attributes

To avoid using the AST when emitting diagnostics, split the "dontcall"
attribute into "dontcall-warn" and "dontcall-error", and also add the
frontend attribute value as the LLVM attribute value. This gives us all
the information to report diagnostics we need from within the IR (aside
from access to the original source).

One downside is we directly use LLVM's demangler rather than using the
existing Clang diagnostic pretty printing of symbols.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D110364

show more ...

[Clang] add support for error+warning fn attrs

Add support for the GNU C style __attribute__((error(""))) and
__attribute__((warning(""))). These attributes are meant to be put on
declarations of fu

[Clang] add support for error+warning fn attrs

Add support for the GNU C style __attribute__((error(""))) and
__attribute__((warning(""))). These attributes are meant to be put on
declarations of functions whom should not be called.

They are frequently used to provide compile time diagnostics similar to
_Static_assert, but which may rely on non-ICE conditions (ie. relying on
compiler optimizations). This is also similar to diagnose_if function
attribute, but can diagnose after optimizations have been run.

While users may instead simply call undefined functions in such cases to
get a linkage failure from the linker, these provide a much more
ergonomic and actionable diagnostic to users and do so at compile time
rather than at link time. Users instead may be able use inline asm .err
directives.

These are used throughout the Linux kernel in its implementation of
BUILD_BUG and BUILD_BUG_ON macros. These macros generally cannot be
converted to use _Static_assert because many of the parameters are not
ICEs. The Linux kernel still needs to be modified to make use of these
when building with Clang; I have a patch that does so I will send once
this feature is landed.

To do so, we create a new IR level Function attribute, "dontcall" (both
error and warning boil down to one IR Fn Attr). Then, similar to calls
to inline asm, we attach a !srcloc Metadata node to call sites of such
attributed callees.

The backend diagnoses these during instruction selection, while we still
know that a call is a call (vs say a JMP that's a tail call) in an arch
agnostic manner.

The frontend then reconstructs the SourceLocation from that Metadata,
and determines whether to emit an error or warning based on the callee's
attribute.

Link: https://bugs.llvm.org/show_bug.cgi?id=16428
Link: https://github.com/ClangBuiltLinux/linux/issues/1173

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D106030

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[clang][codegen] Set CurLinkModule in CodeGenAction::ExecuteAction

CodeGenAction::ExecuteAction creates a BackendConsumer for the
purpose of handling diagnostics. The BackendConsumer's
DiagnosticHan

[clang][codegen] Set CurLinkModule in CodeGenAction::ExecuteAction

CodeGenAction::ExecuteAction creates a BackendConsumer for the
purpose of handling diagnostics. The BackendConsumer's
DiagnosticHandlerImpl method expects CurLinkModule to be set,
but this did not happen on the code path that goes through
ExecuteAction. This change makes it so that the BackendConsumer
constructor used by ExecuteAction requires the Module to be
specified and passes the appropriate module in ExecuteAction.

The change also adds a test that fails without this change
and passes with it. To make the test work, the FIXME in the
handling of DK_Linker diagnostics was addressed so that warnings
and notes are no longer silently discarded. Since this introduces
a new warning diagnostic, a flag to control it (-Wlinker-warnings)
has also been added.

Reviewed By: xur

Differential Revision: https://reviews.llvm.org/D108603

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