[IR][sanitizer] Set nounwind on module ctor/dtor, additionally set uwtable if -fasynchronous-unwind-tables

On ELF targets, if a function has uwtable or personality, or does not have
nounwind (`needs

[IR][sanitizer] Set nounwind on module ctor/dtor, additionally set uwtable if -fasynchronous-unwind-tables

On ELF targets, if a function has uwtable or personality, or does not have
nounwind (`needsUnwindTableEntry`), it marks that `.eh_frame` is needed in the module.

Then, a function gets `.eh_frame` if `needsUnwindTableEntry` or `-g[123]` is specified.
(i.e. If -g[123], every function gets `.eh_frame`.
This behavior is strange but that is the status quo on GCC and Clang.)

Let's take asan as an example. Other sanitizers are similar.
`asan.module_[cd]tor` has no attribute. `needsUnwindTableEntry` returns true,
so every function gets `.eh_frame` if `-g[123]` is specified.
This is the root cause that
`-fno-exceptions -fno-asynchronous-unwind-tables -g` produces .debug_frame
while
`-fno-exceptions -fno-asynchronous-unwind-tables -g -fsanitize=address` produces .eh_frame.

This patch

* sets the nounwind attribute on sanitizer module ctor/dtor.
* let Clang emit a module flag metadata "uwtable" for -fasynchronous-unwind-tables. If "uwtable" is set, sanitizer module ctor/dtor additionally get the uwtable attribute.

The "uwtable" mechanism is generic: synthesized functions not cloned/specialized
from existing ones should consider `Function::createWithDefaultAttr` instead of
`Function::create` if they want to get some default attributes which
have more of module semantics.

Other candidates: "frame-pointer" (https://github.com/ClangBuiltLinux/linux/issues/955
https://github.com/ClangBuiltLinux/linux/issues/1238), dso_local, etc.

Differential Revision: https://reviews.llvm.org/D100251

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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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Revert "[IR] Ignore bitcasts of function pointers which are only used as callees in callbase instruction"

This reverts commit 167ea67d

This causes a bunch of build failures:
* http://lab.llvm.org:8

Revert "[IR] Ignore bitcasts of function pointers which are only used as callees in callbase instruction"

This reverts commit 167ea67d

This causes a bunch of build failures:
* http://lab.llvm.org:8011/#/builders/121/builds/6287
* http://green.lab.llvm.org/green/job/clang-stage1-RA/19915

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[IR] Ignore bitcasts of function pointers which are only used as callees in callbase instruction

This patch enhances hasAddressTaken() to ignore bitcasts as a
callee in callbase instruction. Such bi

[IR] Ignore bitcasts of function pointers which are only used as callees in callbase instruction

This patch enhances hasAddressTaken() to ignore bitcasts as a
callee in callbase instruction. Such bitcast usage doesn't really take
the address in a useful meaningful way.

Reviewed By: rampitec

Differential Revision: https://reviews.llvm.org/D98884

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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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[DAE] Adjust param/arg attributes when changing parameter to undef

In DeadArgumentElimination pass, if a function's argument is never used, corresponding caller's parameter can be changed to undef.

[DAE] Adjust param/arg attributes when changing parameter to undef

In DeadArgumentElimination pass, if a function's argument is never used, corresponding caller's parameter can be changed to undef. If the param/arg has attribute noundef or other related attributes, LLVM LangRef(https://llvm.org/docs/LangRef.html#parameter-attributes) says its behavior is undefined. SimplifyCFG(D97244) takes advantage of this behavior and does bad transformation on valid code.

To avoid this undefined behavior when change caller's parameter to undef, this patch removes noundef attribute and other attributes imply noundef on param/arg.

Differential Revision: https://reviews.llvm.org/D98899

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Support intrinsic overloading on unnamed types

This patch adds support for intrinsic overloading on unnamed types.

This fixes PR38117 and PR48340 and will also be needed for the Full Restrict Patch

Support intrinsic overloading on unnamed types

This patch adds support for intrinsic overloading on unnamed types.

This fixes PR38117 and PR48340 and will also be needed for the Full Restrict Patches (D68484).

The main problem is that the intrinsic overloading name mangling is using 's_s' for unnamed types.
This can result in identical intrinsic mangled names for different function prototypes.

This patch changes this by adding a '.XXXXX' to the intrinsic mangled name when at least one of the types is based on an unnamed type, ensuring that we get a unique name.

Implementation details:
- The mapping is created on demand and kept in Module.
- It also checks for existing clashes and recycles potentially existing prototypes and declarations.
- Because of extra data in Module, Intrinsic::getName needs an extra Module* argument and, for speed, an optional FunctionType* argument.
- I still kept the original two-argument 'Intrinsic::getName' around which keeps the original behavior (providing the base name).
-- Main reason is that I did not want to change the LLVMIntrinsicGetName version, as I don't know how acceptable such a change is
-- The current situation already has a limitation. So that should not get worse with this patch.
- Intrinsic::getDeclaration and the verifier are now using the new version.

Other notes:
- As far as I see, this should not suffer from stability issues. The count is only added for prototypes depending on at least one anonymous struct
- The initial count starts from 0 for each intrinsic mangled name.
- In case of name clashes, existing prototypes are remembered and reused when that makes sense.

Reviewed By: fhahn

Differential Revision: https://reviews.llvm.org/D91250

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Add a couple of missing attribute query methods [NFC]

IR: Fix assert string message referring to the wrong attribute

Option to ignore llvm[.compiler].used uses in hasAddressTaken()

Differential Revision: https://reviews.llvm.org/D96087

Option to ignore assume like intrinsic uses in hasAddressTaken()

Differential Revision: https://reviews.llvm.org/D96081

Allow nonnull/align attribute to accept poison

Currently LLVM is relying on ValueTracking's `isKnownNonZero` to attach `nonnull`, which can return true when the value is poison.
To make the semantic

Allow nonnull/align attribute to accept poison

Currently LLVM is relying on ValueTracking's `isKnownNonZero` to attach `nonnull`, which can return true when the value is poison.
To make the semantics of `nonnull` consistent with the behavior of `isKnownNonZero`, this makes the semantics of `nonnull` to accept poison, and return poison if the input pointer isn't null.
This makes many transformations like below legal:

```
%p = gep inbounds %x, 1 ; % p is non-null pointer or poison
call void @f(%p) ; instcombine converts this to call void @f(nonnull %p)
```

Instead, this semantics makes propagation of `nonnull` to caller illegal.
The reason is that, passing poison to `nonnull` does not immediately raise UB anymore, so such program is still well defined, if the callee does not use the argument.
Having `noundef` attribute there re-allows this.

```
define void @f(i8* %p) { ; functionattr cannot mark %p nonnull here anymore
call void @g(i8* nonnull %p) ; .. because @g never raises UB if it never uses %p.
ret void
}
```

Another attribute that needs to be updated is `align`. This patch updates the semantics of align to accept poison as well.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D90529

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[X86] Add x86_amx type for intel AMX.

The x86_amx is used for AMX intrisics. <256 x i32> is bitcast to x86_amx when
it is used by AMX intrinsics, and x86_amx is bitcast to <256 x i32> when it
is use

[X86] Add x86_amx type for intel AMX.

The x86_amx is used for AMX intrisics. <256 x i32> is bitcast to x86_amx when
it is used by AMX intrinsics, and x86_amx is bitcast to <256 x i32> when it
is used by load/store instruction. So amx intrinsics only operate on type x86_amx.
It can help to separate amx intrinsics from llvm IR instructions (+-*/).
Thank Craig for the idea. This patch depend on https://reviews.llvm.org/D87981.

Differential Revision: https://reviews.llvm.org/D91927

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Small improvements to Intrinsic::getName

While I was adding a new intrinsic instruction (not overloaded), I accidentally used CreateUnaryIntrinsic to create the intrinsics, which turns out to be pas

Small improvements to Intrinsic::getName

While I was adding a new intrinsic instruction (not overloaded), I accidentally used CreateUnaryIntrinsic to create the intrinsics, which turns out to be passing the type list to getName, and ended up naming the intrinsics function with type suffix, which leads to wierd bugs latter on. It took me a long time to debug.
It seems a good idea to add an assertion in getName so that it fails if types are passed but it's not a overloaded function.
Also, the overloade version of getName is less efficient because it creates an std::string. We should avoid calling it if we know that there are no types provided.

Differential Revision: https://reviews.llvm.org/D92523

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[Inline] prevent inlining on stack protector mismatch

It's common for code that manipulates the stack via inline assembly or
that has to set up its own stack canary (such as the Linux kernel) would

[Inline] prevent inlining on stack protector mismatch

It's common for code that manipulates the stack via inline assembly or
that has to set up its own stack canary (such as the Linux kernel) would
like to avoid stack protectors in certain functions. In this case, we've
been bitten by numerous bugs where a callee with a stack protector is
inlined into an attribute((no_stack_protector)) caller, which
generally breaks the caller's assumptions about not having a stack
protector. LTO exacerbates the issue.

While developers can avoid this by putting all no_stack_protector
functions in one translation unit together and compiling those with
-fno-stack-protector, it's generally not very ergonomic or as
ergonomic as a function attribute, and still doesn't work for LTO. See also:
https://lore.kernel.org/linux-pm/20200915172658.1432732-1-rkir@google.com/
https://lore.kernel.org/lkml/20200918201436.2932360-30-samitolvanen@google.com/T/#u

SSP attributes can be ordered by strength. Weakest to strongest, they
are: ssp, sspstrong, sspreq. Callees with differing SSP attributes may be
inlined into each other, and the strongest attribute will be applied to the
caller. (No change)

After this change:
* A callee with no SSP attributes will no longer be inlined into a
caller with SSP attributes.
* The reverse is also true: a callee with an SSP attribute will not be
inlined into a caller with no SSP attributes.
* The alwaysinline attribute overrides these rules.

Functions that get synthesized by the compiler may not get inlined as a
result if they are not created with the same stack protector function
attribute as their callers.

Alternative approach to https://reviews.llvm.org/D87956.

Fixes pr/47479.

Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>

Reviewed By: rnk, MaskRay

Differential Revision: https://reviews.llvm.org/D91816

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[VE] Support vld intrinsics

Add intrinsics for vector load instructions. Add a regression test also.

Reviewed By: simoll

Differential Revision: https://reviews.llvm.org/D91332

[CostModel] Make target intrinsics cheap by default

This patch changes the intrinsics cost model to assume that by default
target intrinsics are cheap. This didn't seem to be the case for all
intrin

[CostModel] Make target intrinsics cheap by default

This patch changes the intrinsics cost model to assume that by default
target intrinsics are cheap. This didn't seem to be the case for all
intrinsics, and is potentially an MVE problem due to our scalarization
overheads. Cheap seems to be a good default in general though.

Differential Revision: https://reviews.llvm.org/D90597

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[PowerPC] Add assemble disassemble intrinsics for MMA

This patch adds support for assemble disassemble intrinsics
for MMA.

Reviewed By: bsaleil, #powerpc

Differential Revision: https://reviews.llv

[PowerPC] Add assemble disassemble intrinsics for MMA

This patch adds support for assemble disassemble intrinsics
for MMA.

Reviewed By: bsaleil, #powerpc

Differential Revision: https://reviews.llvm.org/D88739

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[X86] Support Intel Key Locker

Key Locker provides a mechanism to encrypt and decrypt data with an AES key without having access
to the raw key value by converting AES keys into “handles”. These han

[X86] Support Intel Key Locker

Key Locker provides a mechanism to encrypt and decrypt data with an AES key without having access
to the raw key value by converting AES keys into “handles”. These handles can be used to perform the
same encryption and decryption operations as the original AES keys, but they only work on the current
system and only until they are revoked. If software revokes Key Locker handles (e.g., on a reboot),
then any previous handles can no longer be used.

Reviewed By: craig.topper

Differential Revision: https://reviews.llvm.org/D88398

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OpaquePtr: Add helpers for sret to mirror byval

Sret should really have a type parameter like byval does.

IR: Move denormal mode parsing from MachineFunction to Function

This was just inspecting the IR to begin with, and is useful to check
in some places in the IR.