[Clang] Add fake use emission to Clang with -fextend-lifetimes (#110102)

Following the previous patch which adds the "extend lifetimes" flag
without (almost) any functionality, this patch adds the r

[Clang] Add fake use emission to Clang with -fextend-lifetimes (#110102)

Following the previous patch which adds the "extend lifetimes" flag
without (almost) any functionality, this patch adds the real feature by
allowing Clang to emit fake uses. These are emitted as a new form of cleanup,
set for variable addresses, which just emits a fake use intrinsic when the
variable falls out of scope. The code for achieving this is simple, with most
of the logic centered on determining whether to emit a fake use for a given
address, and on ensuring that fake uses are ignored in a few cases.

Co-authored-by: Stephen Tozer <stephen.tozer@sony.com>

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[clang] Use {} instead of std::nullopt to initialize empty ArrayRef (#109399)

Follow up to #109133.

[NFC][Clang] clang-format a function declaration

[DebugInfo][RemoveDIs] Use iterator-inserters in clang (#102006)

As part of the LLVM effort to eliminate debug-info intrinsics, we're
moving to a world where only iterators should be used to insert

[DebugInfo][RemoveDIs] Use iterator-inserters in clang (#102006)

As part of the LLVM effort to eliminate debug-info intrinsics, we're
moving to a world where only iterators should be used to insert
instructions. This isn't a problem in clang when instructions get
generated before any debug-info is inserted, however we're planning on
deprecating and removing the instruction-pointer insertion routines.

Scatter some calls to getIterator in a few places, remove a
deref-then-addrof on another iterator, and add an overload for the
createLoadInstBefore utility. Some callers passes a null insertion
point, which we need to handle explicitly now.

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[CodeGen] Remove IsVolatile from DominatingValue<RValue>::save_type (#95165)

Prior to 84780af4b02cb3b86e4cb724f996bf8e02f2f2e7, the class didn't have
any information about whether the saved value w

[CodeGen] Remove IsVolatile from DominatingValue<RValue>::save_type (#95165)

Prior to 84780af4b02cb3b86e4cb724f996bf8e02f2f2e7, the class didn't have
any information about whether the saved value was volatile.

This is NFC as far as I can tell.

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Re-apply "Emit missing cleanups for stmt-expr" and other commits (#89154)

Latest diff:
https://github.com/llvm/llvm-project/pull/89154/files/f1ab4c2677394bbfc985d9680d5eecd7b2e6a882..adf9bc902baddb

Re-apply "Emit missing cleanups for stmt-expr" and other commits (#89154)

Latest diff:
https://github.com/llvm/llvm-project/pull/89154/files/f1ab4c2677394bbfc985d9680d5eecd7b2e6a882..adf9bc902baddb156c83ce0f8ec03c142e806d45

We address two additional bugs here:

### Problem 1: Deactivated normal cleanup still runs, leading to
double-free
Consider the following:
```cpp

struct A { };

struct B { B(const A&); };

struct S {
A a;
B b;
};

int AcceptS(S s);

void Accept2(int x, int y);

void Test() {
Accept2(AcceptS({.a = A{}, .b = A{}}), ({ return; 0; }));
}
```
We add cleanups as follows:
1. push dtor for field `S::a`
2. push dtor for temp `A{}` (used by ` B(const A&)` in `.b = A{}`)
3. push dtor for field `S::b`
4. Deactivate 3 `S::b`-> This pops the cleanup.
5. Deactivate 1 `S::a` -> Does not pop the cleanup as *2* is top. Should
create _active flag_!!
6. push dtor for `~S()`.
7. ...

It is important to deactivate **5** using active flags. Without the
active flags, the `return` will fallthrough it and would run both `~S()`
and dtor `S::a` leading to **double free** of `~A()`.
In this patch, we unconditionally emit active flags while deactivating
normal cleanups. These flags are deleted later by the `AllocaTracker` if
the cleanup is not emitted.

### Problem 2: Missing cleanup for conditional lifetime extension
We push 2 cleanups for lifetime-extended cleanup. The first cleanup is
useful if we exit from the middle of the expression (stmt-expr/coro
suspensions). This is deactivated after full-expr, and a new cleanup is
pushed, extending the lifetime of the temporaries (to the scope of the
reference being initialized).
If this lifetime extension happens to be conditional, then we use active
flags to remember whether the branch was taken and if the object was
initialized.
Previously, we used a **single** active flag, which was used by both
cleanups. This is wrong because the first cleanup will be forced to
deactivate after the full-expr and therefore this **active** flag will
always be **inactive**. The dtor for the lifetime extended entity would
not run as it always sees an **inactive** flag.

In this patch, we solve this using two separate active flags for both
cleanups. Both of them are activated if the conditional branch is taken,
but only one of them is deactivated after the full-expr.

---

Fixes https://github.com/llvm/llvm-project/issues/63818
Fixes https://github.com/llvm/llvm-project/issues/88478

---

Previous PR logs:
1. https://github.com/llvm/llvm-project/pull/85398
2. https://github.com/llvm/llvm-project/pull/88670
3. https://github.com/llvm/llvm-project/pull/88751
4. https://github.com/llvm/llvm-project/pull/88884

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Revert "[codegen] Emit missing cleanups for stmt-expr and coro suspensions" and related commits (#88884)

The original change caused widespread breakages in msan/ubsan tests and
causes `use-after-fr

Revert "[codegen] Emit missing cleanups for stmt-expr and coro suspensions" and related commits (#88884)

The original change caused widespread breakages in msan/ubsan tests and
causes `use-after-free`. Most likely we are adding more cleanups than
necessary.

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Fix missing dtor in function calls accepting trivial ABI structs (#88751)

Fixes https://github.com/llvm/llvm-project/issues/88478

Promoting the `EHCleanup` to `NormalAndEHCleanup` in `EmitCallArg

Fix missing dtor in function calls accepting trivial ABI structs (#88751)

Fixes https://github.com/llvm/llvm-project/issues/88478

Promoting the `EHCleanup` to `NormalAndEHCleanup` in `EmitCallArgs`
surfaced another bug with deactivation of normal cleanups. Here we
missed emitting CPP scope ends for deactivated normal cleanups. This
patch also fixes that bug.

We missed emitting CPP scope ends because we remove the `fallthrough`
(clears the insertion point) before deactivating normal cleanups. This
is to make the emitted "normal" cleanup code unreachable. But we still
need to emit CPP scope ends in the original basic block even for a
deactivated normal cleanup.
(This worked correctly before we did not remove `fallthrough` for
`EHCleanup`s).

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[codegen] Emit missing cleanups for stmt-expr and coro suspensions [take-2] (#85398)

Fixes https://github.com/llvm/llvm-project/issues/63818 for control flow
out of an expressions.

#### Backgrou

[codegen] Emit missing cleanups for stmt-expr and coro suspensions [take-2] (#85398)

Fixes https://github.com/llvm/llvm-project/issues/63818 for control flow
out of an expressions.

#### Background

A control flow could happen in the middle of an expression due to
stmt-expr and coroutine suspensions.

Due to branch-in-expr, we missed running cleanups for the temporaries
constructed in the expression before the branch.
Previously, these cleanups were only added as `EHCleanup` during the
expression and as normal expression after the full expression.

Examples of such deferred cleanups include:

`ParenList/InitList`: Cleanups for fields are performed by the
destructor of the object being constructed.
`Array init`: Cleanup for elements of an array is included in the array
cleanup.
`Lifetime-extended temporaries`: reference-binding temporaries in
braced-init are lifetime extended to the parent scope.
`Lambda capture init`: init in the lambda capture list is destroyed by
the lambda object.

---

#### In this PR

In this PR, we change some of the `EHCleanups` cleanups to
`NormalAndEHCleanups` to make sure these are emitted when we see a
branch inside an expression (through statement expressions or coroutine
suspensions).

These are supposed to be deactivated after full expression and destroyed
later as part of the destructor of the aggregate or array being
constructed. To simplify deactivating cleanups, we add two utilities as
well:
* `DeferredDeactivationCleanupStack`: A stack to remember cleanups with
deferred deactivation.
* `CleanupDeactivationScope`: RAII for deactivating cleanups added to
the above stack.

---

#### Deactivating normal cleanups
These were previously `EHCleanups` and not `Normal` and **deactivation**
of **required** `Normal` cleanups had some bugs. These specifically
include deactivating `Normal` cleanups which are not the top of
`EHStack`
[source1](https://github.com/llvm/llvm-project/blob/92b56011e6b61e7dc1628c0431ece432f282b3cb/clang/lib/CodeGen/CGCleanup.cpp#L1319),
[2](https://github.com/llvm/llvm-project/blob/92b56011e6b61e7dc1628c0431ece432f282b3cb/clang/lib/CodeGen/CGCleanup.cpp#L722-L746).
This has not been part of our test suite (maybe it was never required
before statement expressions). In this PR, we also fix the emission of
required-deactivated-normal cleanups.

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[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86923)

To authenticate pointers, CodeGen needs access to the key and
discriminators tha

[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86923)

To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.

This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.

In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.

This reapplies d9a685a9dd589486e882b722e513ee7b8c84870c, which was
reverted because it broke ubsan bots. There seems to be a bug in
coroutine code-gen, which is causing EmitTypeCheck to use the wrong
alignment. For now, pass alignment zero to EmitTypeCheck so that it can
compute the correct alignment based on the passed type (see function
EmitCXXMemberOrOperatorMemberCallExpr).

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Revert "[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86721)" (#86898)

This reverts commit d9a685a9dd589486e882b722e513ee7b8c84870c.

Revert "[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86721)" (#86898)

This reverts commit d9a685a9dd589486e882b722e513ee7b8c84870c.

The commit broke ubsan bots.

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[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86721)

To authenticate pointers, CodeGen needs access to the key and
discriminators th

[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#86721)

To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.

This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.

In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.

This reapplies 8bd1f9116aab879183f34707e6d21c7051d083b6. The commit
broke msan bots because LValue::IsKnownNonNull was uninitialized.

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Revert "[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#67454)" (#86674)

This reverts commit 8bd1f9116aab879183f34707e6d21c7051d083b6.

Revert "[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#67454)" (#86674)

This reverts commit 8bd1f9116aab879183f34707e6d21c7051d083b6.

It appears that the commit broke msan bots.

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[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#67454)

To authenticate pointers, CodeGen needs access to the key and
discriminators tha

[CodeGen][arm64e] Add methods and data members to Address, which are needed to authenticate signed pointers (#67454)

To authenticate pointers, CodeGen needs access to the key and
discriminators that were used to sign the pointer. That information is
sometimes known from the context, but not always, which is why `Address`
needs to hold that information.

This patch adds methods and data members to `Address`, which will be
needed in subsequent patches to authenticate signed pointers, and uses
the newly added methods throughout CodeGen. Although this patch isn't
strictly NFC as it causes CodeGen to use different code paths in some
cases (e.g., `mergeAddressesInConditionalExpr`), it doesn't cause any
changes in functionality as it doesn't add any information needed for
authentication.

In addition to the changes mentioned above, this patch introduces class
`RawAddress`, which contains a pointer that we know is unsigned, and
adds several new functions for creating `Address` and `LValue` objects.

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[SEH] Fix wrong argument passes to the call of OutlinedFinally.

When return out of __try block. In this test case, currently "false" is
passed to OutlinedFinally's call. "true" should be passed to

[SEH] Fix wrong argument passes to the call of OutlinedFinally.

When return out of __try block. In this test case, currently "false" is
passed to OutlinedFinally's call. "true" should be passed to indicate
abnormal terminations.

The rule: Except _leave and fall-through at the end, all other exits
in a _try (return/goto/continue/break) are considered as abnormal
terminations, NormalCleanupDestSlot is used to indicate abnormal
terminations.

The problem is, during the processing abnormal terminations,
the ExitSwitch is used. However, in this case, Existswitch is route out.

One way to fix is to skip route it without a switch. So proper
abnormal termination's code could be generated.

Differential Revision: https://reviews.llvm.org/D158233

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Fix assertion when -fasy-exception is used.

The assertion only happens with use of -fasy-exception without
-fexcessions.

The assertion appen during the call to generate SehScopeBegin(), where
asser

Fix assertion when -fasy-exception is used.

The assertion only happens with use of -fasy-exception without
-fexcessions.

The assertion appen during the call to generate SehScopeBegin(), where
assert with:
assert(CGF.Builder.GetInsertBlock() && InvokeDest);
InvokeDest is null. Because exceptions are disabled, and SEH is not
in use.
The fix is before call EmitSehCppScopeBegin check getInvokeDest(),
to avoid assert during the emit llvm.seh.scope.begin()

Differential Revision: https://reviews.llvm.org/D157566

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[Windows SEH] Fix ehcleanup crash for Windows -EHa

`Builder.GetInsertBlock()` may return null sometimes. https://godbolt.org/z/n1Ph47jP1

Reviewed By: efriedma

Differential Revision: https://review

[Windows SEH] Fix ehcleanup crash for Windows -EHa

`Builder.GetInsertBlock()` may return null sometimes. https://godbolt.org/z/n1Ph47jP1

Reviewed By: efriedma

Differential Revision: https://reviews.llvm.org/D147867

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[Windows SEH] Fix catch+return crash for Windows -EHa

This change also turns on -fasync-exceptions by default under -EHa
option due to the backend patch merged.

Reviewed By: LuoYuanke

Differential

[Windows SEH] Fix catch+return crash for Windows -EHa

This change also turns on -fasync-exceptions by default under -EHa
option due to the backend patch merged.

Reviewed By: LuoYuanke

Differential Revision: https://reviews.llvm.org/D147165

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[NFC] Rename Instruction::insertAt() to Instruction::insertInto(), to be consistent with BasicBlock::insertInto()

Differential Revision: https://reviews.llvm.org/D140085

[NFC] Cleanup: Replaces BB->getInstList().insert() with I->insertAt().

This is part of a series of cleanup patches towards making BasicBlock::getInstList() private.

Differential Revision: https://r

[NFC] Cleanup: Replaces BB->getInstList().insert() with I->insertAt().

This is part of a series of cleanup patches towards making BasicBlock::getInstList() private.

Differential Revision: https://reviews.llvm.org/D138877

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[CodeGen] Use std::nullopt instead of None (NFC)

This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of

[CodeGen] Use std::nullopt instead of None (NFC)

This patch mechanically replaces None with std::nullopt where the
compiler would warn if None were deprecated. The intent is to reduce
the amount of manual work required in migrating from Optional to
std::optional.

This is part of an effort to migrate from llvm::Optional to
std::optional:

https://discourse.llvm.org/t/deprecating-llvm-optional-x-hasvalue-getvalue-getvalueor/63716

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Use CTAD on llvm::SaveAndRestore

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D139229

[NFC] Cleanup: Replaces BB->getInstList().splice() with BB->splice().

This is part of a series of cleanup patches towards making BasicBlock::getInstList() private.

Differential Revision: https://re

[NFC] Cleanup: Replaces BB->getInstList().splice() with BB->splice().

This is part of a series of cleanup patches towards making BasicBlock::getInstList() private.

Differential Revision: https://reviews.llvm.org/D138979

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[NFC][Alignment] Use MaybeAlign in CGCleanup/CGExpr

[CodeGen] Store element type in DominatingValue<RValue>

For aggregate rvalues, we need to store the element type in the
dominating value, so we can recover the element type for the
address.