Remove 'no_sanitize_memtag'. Add 'sanitize_memtag'.

For MTE globals, we should have clang emit the attribute for all GV's
that it creates, and then use that in the upcoming AArch64 global
tagging IR

Remove 'no_sanitize_memtag'. Add 'sanitize_memtag'.

For MTE globals, we should have clang emit the attribute for all GV's
that it creates, and then use that in the upcoming AArch64 global
tagging IR pass. We need a positive attribute for this sanitizer (rather
than implicit sanitization of all globals) because it needs to interact
with other parts of LLVM, including:

1. Suppressing certain global optimisations (like merging),
2. Emitting extra directives by the ASM writer, and
3. Putting extra information in the symbol table entries.

While this does technically make the LLVM IR / bitcode format
non-backwards-compatible, nobody should have used this attribute yet,
because it's a no-op.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D128950

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[LLVM] Add the support for fmax and fmin in atomicrmw instruction

This patch adds the support for `fmax` and `fmin` operations in `atomicrmw`
instruction. For now (at least in this patch), the instr

[LLVM] Add the support for fmax and fmin in atomicrmw instruction

This patch adds the support for `fmax` and `fmin` operations in `atomicrmw`
instruction. For now (at least in this patch), the instruction will be expanded
to CAS loop. There are already a couple of targets supporting the feature. I'll
create another patch(es) to enable them accordingly.

Reviewed By: arsenm

Differential Revision: https://reviews.llvm.org/D127041

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Add sanitizer-specific GlobalValue attributes.

Plan is the migrate the global variable metadata for sanitizers, that's
currently carried around generally in the 'llvm.asan.globals' section,
onto the

Add sanitizer-specific GlobalValue attributes.

Plan is the migrate the global variable metadata for sanitizers, that's
currently carried around generally in the 'llvm.asan.globals' section,
onto the global variable itself.

This patch adds the attribute and plumbs it through the LLVM IR and
bitcode formats, but is a no-op other than that so far.

Reviewed By: vitalybuka, kstoimenov

Differential Revision: https://reviews.llvm.org/D126100

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[Bitcode] Re-enable verify-uselistorder test (NFC)

This issue has since been fixed, so re-enable the commented RUN
line.

attributes: introduce allockind attr for describing allocator fn behavior

I chose to encode the allockind information in a string constant because
otherwise we would get a bit of an explosion of key

attributes: introduce allockind attr for describing allocator fn behavior

I chose to encode the allockind information in a string constant because
otherwise we would get a bit of an explosion of keywords to deal with
the possible permutations of allocation function types.

I'm not sure that CodeGen.h is the correct place for this enum, but it
seemed to kind of match the UWTableKind enum so I put it in the same
place. Constructive suggestions on a better location most certainly
encouraged.

Differential Revision: https://reviews.llvm.org/D123088

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Allow pointer types for atomicrmw xchg

This adds support for pointer types for `atomic xchg` and let us write
instructions such as `atomicrmw xchg i64** %0, i64* %1 seq_cst`. This
is similar to the

Allow pointer types for atomicrmw xchg

This adds support for pointer types for `atomic xchg` and let us write
instructions such as `atomicrmw xchg i64** %0, i64* %1 seq_cst`. This
is similar to the patch for allowing atomicrmw xchg on floating point
types: https://reviews.llvm.org/D52416.

Differential Revision: https://reviews.llvm.org/D124728

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Attributes: add a new `allocptr` attribute

This continues the push away from hard-coded knowledge about functions
towards attributes. We'll use this to annotate free(), realloc() and
cousins and obv

Attributes: add a new `allocptr` attribute

This continues the push away from hard-coded knowledge about functions
towards attributes. We'll use this to annotate free(), realloc() and
cousins and obviate the hard-coded list of free functions.

Differential Revision: https://reviews.llvm.org/D123083

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Reapply "[Intrinsics] Add `nocallback` to the default intrinsic attributes"

This reverts commit c5f789050daab25aad6770790987e2b7c0395936 and
reapplies 7aea3ea8c3b33c9bb338d5d6c0e4832be1d09ac3 with a

Reapply "[Intrinsics] Add `nocallback` to the default intrinsic attributes"

This reverts commit c5f789050daab25aad6770790987e2b7c0395936 and
reapplies 7aea3ea8c3b33c9bb338d5d6c0e4832be1d09ac3 with additional test
changes.

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Attributes: add a new allocalign attribute

This will let us start moving away from hard-coded attributes in
MemoryBuiltins.cpp and put the knowledge about various attribute
functions in the compiler

Attributes: add a new allocalign attribute

This will let us start moving away from hard-coded attributes in
MemoryBuiltins.cpp and put the knowledge about various attribute
functions in the compilers that emit those calls where it probably
belongs.

Differential Revision: https://reviews.llvm.org/D117921

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[SanitizerBounds] Add support for NoSanitizeBounds function

Currently adding attribute no_sanitize("bounds") isn't disabling
-fsanitize=local-bounds (also enabled in -fsanitize=bounds). The Clang
fr

[SanitizerBounds] Add support for NoSanitizeBounds function

Currently adding attribute no_sanitize("bounds") isn't disabling
-fsanitize=local-bounds (also enabled in -fsanitize=bounds). The Clang
frontend handles fsanitize=array-bounds which can already be disabled by
no_sanitize("bounds"). However, instrumentation added by the
BoundsChecking pass in the middle-end cannot be disabled by the
attribute.

The fix is very similar to D102772 that added the ability to selectively
disable sanitizer pass on certain functions.

In this patch, if no_sanitize("bounds") is provided, an additional
function attribute (NoSanitizeBounds) is attached to IR to let the
BoundsChecking pass know we want to disable local-bounds checking. In
order to support this feature, the IR is extended (similar to D102772)
to make Clang able to preserve the information and let BoundsChecking
pass know bounds checking is disabled for certain function.

Reviewed By: melver

Differential Revision: https://reviews.llvm.org/D119816

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add IR compatability test for (upcoming) allocsize attribute

[Verifier] Add verification logic for GlobalIFuncs

Verify that the resolver exists, that it is a defined
Function, and that its return type matches the ifunc's
type. Add corresponding check to Bitco

[Verifier] Add verification logic for GlobalIFuncs

Verify that the resolver exists, that it is a defined
Function, and that its return type matches the ifunc's
type. Add corresponding check to BitcodeReader, change
clang to emit the correct type, and fix tests to comply.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D112349

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[clang][Codegen] Introduce the disable_sanitizer_instrumentation attribute

The purpose of __attribute__((disable_sanitizer_instrumentation)) is to
prevent all kinds of sanitizer instrumentation appl

[clang][Codegen] Introduce the disable_sanitizer_instrumentation attribute

The purpose of __attribute__((disable_sanitizer_instrumentation)) is to
prevent all kinds of sanitizer instrumentation applied to a certain
function, Objective-C method, or global variable.

The no_sanitize(...) attribute drops instrumentation checks, but may
still insert code preventing false positive reports. In some cases
though (e.g. when building Linux kernel with -fsanitize=kernel-memory
or -fsanitize=thread) the users may want to avoid any kind of
instrumentation.

Differential Revision: https://reviews.llvm.org/D108029

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[IR] Rename `comdat noduplicates` to `comdat nodeduplicate`

In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are re

[IR] Rename `comdat noduplicates` to `comdat nodeduplicate`

In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are retained, and
they happen to define strong external symbols with the same names,
there will be a duplicate definition linker error.

In PE/COFF, the selection kind lowers to `IMAGE_COMDAT_SELECT_NODUPLICATES`.
The name describes the corollary instead of the immediate semantics. The name
can cause confusion to other binary formats (ELF, wasm) which have implemented/
want to implement the "no deduplication" selection kind. Rename it to be clearer.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D106319

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[SanitizeCoverage] Add support for NoSanitizeCoverage function attribute

We really ought to support no_sanitize("coverage") in line with other
sanitizers. This came up again in discussions on the Li

[SanitizeCoverage] Add support for NoSanitizeCoverage function attribute

We really ought to support no_sanitize("coverage") in line with other
sanitizers. This came up again in discussions on the Linux-kernel
mailing lists, because we currently do workarounds using objtool to
remove coverage instrumentation. Since that support is only on x86, to
continue support coverage instrumentation on other architectures, we
must support selectively disabling coverage instrumentation via function
attributes.

Unfortunately, for SanitizeCoverage, it has not been implemented as a
sanitizer via fsanitize= and associated options in Sanitizers.def, but
rolls its own option fsanitize-coverage. This meant that we never got
"automatic" no_sanitize attribute support.

Implement no_sanitize attribute support by special-casing the string
"coverage" in the NoSanitizeAttr implementation. To keep the feature as
unintrusive to existing IR generation as possible, define a new negative
function attribute NoSanitizeCoverage to propagate the information
through to the instrumentation pass.

Fixes: https://bugs.llvm.org/show_bug.cgi?id=49035

Reviewed By: vitalybuka, morehouse

Differential Revision: https://reviews.llvm.org/D102772

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IR/AArch64/X86: add "swifttailcc" calling convention.

Swift's new concurrency features are going to require guaranteed tail calls so
that they don't consume excessive amounts of stack space. This wo

IR/AArch64/X86: add "swifttailcc" calling convention.

Swift's new concurrency features are going to require guaranteed tail calls so
that they don't consume excessive amounts of stack space. This would normally
mean "tailcc", but there are also Swift-specific ABI desires that don't
naturally go along with "tailcc" so this adds another calling convention that's
the combination of "swiftcc" and "tailcc".

Support is added for AArch64 and X86 for now.

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IR+AArch64: add a "swiftasync" argument attribute.

This extends any frame record created in the function to include that
parameter, passed in X22.

The new record looks like [X22, FP, LR] in memory,

IR+AArch64: add a "swiftasync" argument attribute.

This extends any frame record created in the function to include that
parameter, passed in X22.

The new record looks like [X22, FP, LR] in memory, and FP is stored with 0b0001
in bits 63:60 (CodeGen assumes they are 0b0000 in normal operation). The effect
of this is that tools walking the stack should expect to see one of three
values there:

* 0b0000 => a normal, non-extended record with just [FP, LR]
* 0b0001 => the extended record [X22, FP, LR]
* 0b1111 => kernel space, and a non-extended record.

All other values are currently reserved.

If compiling for arm64e this context pointer is address-discriminated with the
discriminator 0xc31a and the DB (process-specific) key.

There is also an "i8** @llvm.swift.async.context.addr()" intrinsic providing
front-ends access to this slot (and forcing its creation initialized to nullptr
if necessary).

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[clang][AArch64] Correctly align HFA arguments when passed on the stack

When we pass a AArch64 Homogeneous Floating-Point
Aggregate (HFA) argument with increased alignment
requirements, for example

[clang][AArch64] Correctly align HFA arguments when passed on the stack

When we pass a AArch64 Homogeneous Floating-Point
Aggregate (HFA) argument with increased alignment
requirements, for example

struct S {
__attribute__ ((__aligned__(16))) double v[4];
};

Clang uses `[4 x double]` for the parameter, which is passed
on the stack at alignment 8, whereas it should be at
alignment 16, following Rule C.4 in
AAPCS (https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#642parameter-passing-rules)

Currently we don't have a way to express in LLVM IR the
alignment requirements of the function arguments. The align
attribute is applicable to pointers only, and only for some
special ways of passing arguments (e..g byval). When
implementing AAPCS32/AAPCS64, clang resorts to dubious hacks
of coercing to types, which naturally have the needed
alignment. We don't have enough types to cover all the
cases, though.

This patch introduces a new use of the stackalign attribute
to control stack slot alignment, when and if an argument is
passed in memory.

The attribute align is left as an optimizer hint - it still
applies to pointer types only and pertains to the content of
the pointer, whereas the alignment of the pointer itself is
determined by the stackalign attribute.

For byval arguments, the stackalign attribute assumes the
role, previously perfomed by align, falling back to align if
stackalign` is absent.

On the clang side, when passing arguments using the "direct"
style (cf. `ABIArgInfo::Kind`), now we can optionally
specify an alignment, which is emitted as the new
`stackalign` attribute.

Patch by Momchil Velikov and Lucas Prates.

Differential Revision: https://reviews.llvm.org/D98794

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Reapply "OpaquePtr: Turn inalloca into a type attribute"

This reverts commit 07e46367baeca96d84b03fa215b41775f69d5989.

Revert "Reapply "OpaquePtr: Turn inalloca into a type attribute""

Reverting because test 'Bindings/Go/go.test' is failing on most
buildbots.

This reverts commit fc9df309917e57de704f3ce4372138a8d4a2

Revert "Reapply "OpaquePtr: Turn inalloca into a type attribute""

Reverting because test 'Bindings/Go/go.test' is failing on most
buildbots.

This reverts commit fc9df309917e57de704f3ce4372138a8d4a23d7a.

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Reapply "OpaquePtr: Turn inalloca into a type attribute"

This reverts commit 20d5c42e0ef5d252b434bcb610b04f1cb79fe771.

Revert "OpaquePtr: Turn inalloca into a type attribute"

This reverts commit 4fefed65637ec46c8c2edad6b07b5569ac61e9e5.
Broke check-clang everywhere.

OpaquePtr: Turn inalloca into a type attribute

I think byval/sret and the others are close to being able to rip out
the code to support the missing type case. A lot of this code is
shared with inall

OpaquePtr: Turn inalloca into a type attribute

I think byval/sret and the others are close to being able to rip out
the code to support the missing type case. A lot of this code is
shared with inalloca, so catch this up to the others so that can
happen.

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Encode alignment attribute for `cmpxchg`

This is a follow up patch to D83136 adding the align attribute to `cmpxchg`.
See also D83465 for `atomicrmw`.

Differential Revision: https://reviews.llvm.or

Encode alignment attribute for `cmpxchg`

This is a follow up patch to D83136 adding the align attribute to `cmpxchg`.
See also D83465 for `atomicrmw`.

Differential Revision: https://reviews.llvm.org/D87443

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Encode alignment attribute for `atomicrmw`

This is a follow up patch to D83136 adding the align attribute to `atomicwmw`.

Differential Revision: https://reviews.llvm.org/D83465