[clang][ExprConstant] Print template arguments when describing stack frame

This patch adds additional printing of template argument list when the described function is a template specialization.
Thi

[clang][ExprConstant] Print template arguments when describing stack frame

This patch adds additional printing of template argument list when the described function is a template specialization.
This can be useful when handling complex template functions in constexpr evaluator.

Reviewed By: cjdb, dblaikie
Differential Revision: https://reviews.llvm.org/D154366

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[Clang][Attribute] Improve the AST/diagnoses fidelity of alignas and _Alignas

- Fix diagnoses when the argument to `alignas` or `_Alignas` is an incomplete type.

Before:
```
./alignas.cpp:1:15: err

[Clang][Attribute] Improve the AST/diagnoses fidelity of alignas and _Alignas

- Fix diagnoses when the argument to `alignas` or `_Alignas` is an incomplete type.

Before:
```
./alignas.cpp:1:15: error: invalid application of 'alignof' to an incomplete type 'void'
class alignas(void) Foo {};
~^~~~~
1 error generated.
```
Now:
```
./alignas.cpp:1:15: error: invalid application of 'alignas' to an incomplete type 'void'
class alignas(void) Foo {};
~^~~~~
1 error generated.
```

- Improve the AST fidelity of `alignas` and `_Alignas` attribute.

Before:
```
AlignedAttr 0x13f07f278 <col:7> alignas
`-ConstantExpr 0x13f07f258 <col:15, col:21> 'unsigned long'
|-value: Int 8
`-UnaryExprOrTypeTraitExpr 0x13f07f118 <col:15, col:21> 'unsigned long' alignof 'void *'
```

Now:
```
AlignedAttr 0x14288c608 <col:7> alignas 'void *'
```

Reviewed By: erichkeane

Differential Revision: https://reviews.llvm.org/D150528

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Fixed a number of typos

I went over the output of the following mess of a command:

(ulimit -m 2000000; ulimit -v 2000000; git ls-files -z |
parallel --xargs -0 cat | aspell list --mode=none --igno

Fixed a number of typos

I went over the output of the following mess of a command:

(ulimit -m 2000000; ulimit -v 2000000; git ls-files -z |
parallel --xargs -0 cat | aspell list --mode=none --ignore-case |
grep -E '^[A-Za-z][a-z]*$' | sort | uniq -c | sort -n |
grep -vE '.{25}' | aspell pipe -W3 | grep : | cut -d' ' -f2 | less)

and proceeded to spend a few days looking at it to find probable typos
and fixed a few hundred of them in all of the llvm project (note, the
ones I found are not anywhere near all of them, but it seems like a
good start).

Differential Revision: https://reviews.llvm.org/D130827

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Add type information to integral template argument if required.

Non-comprehensive list of cases:
* Dumping template arguments;
* Corresponding parameter contains a deduced type;
* Template argume

Add type information to integral template argument if required.

Non-comprehensive list of cases:
* Dumping template arguments;
* Corresponding parameter contains a deduced type;
* Template arguments are for a DeclRefExpr that hadMultipleCandidates()

Type information is added in the form of prefixes (u8, u, U, L),
suffixes (U, L, UL, LL, ULL) or explicit casts to printed integral template
argument, if MSVC codeview mode is disabled.

Differential revision: https://reviews.llvm.org/D77598

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[clang] Check ValueDependent instead of InstantiationDependent before executing the align expr for builtin align functions.

in general, value dependent is a subset of instnatiation dependent. This
w

[clang] Check ValueDependent instead of InstantiationDependent before executing the align expr for builtin align functions.

in general, value dependent is a subset of instnatiation dependent. This
would allows us to produce diagnostics for the align expression (which
is instantiation dependent but not value dependent).

Differential Revision: https://reviews.llvm.org/D83074

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Add builtins for aligning and checking alignment of pointers and integers

This change introduces three new builtins (which work on both pointers
and integers) that can be used instead of common bitw

Add builtins for aligning and checking alignment of pointers and integers

This change introduces three new builtins (which work on both pointers
and integers) that can be used instead of common bitwise arithmetic:
__builtin_align_up(x, alignment), __builtin_align_down(x, alignment) and
__builtin_is_aligned(x, alignment).

I originally added these builtins to the CHERI fork of LLVM a few years ago
to handle the slightly different C semantics that we use for CHERI [1].
Until recently these builtins (or sequences of other builtins) were
required to generate correct code. I have since made changes to the default
C semantics so that they are no longer strictly necessary (but using them
does generate slightly more efficient code). However, based on our experience
using them in various projects over the past few years, I believe that adding
these builtins to clang would be useful.

These builtins have the following benefit over bit-manipulation and casts
via uintptr_t:

- The named builtins clearly convey the semantics of the operation. While
checking alignment using __builtin_is_aligned(x, 16) versus
((x & 15) == 0) is probably not a huge win in readably, I personally find
__builtin_align_up(x, N) a lot easier to read than (x+(N-1))&~(N-1).
- They preserve the type of the argument (including const qualifiers). When
using casts via uintptr_t, it is easy to cast to the wrong type or strip
qualifiers such as const.
- If the alignment argument is a constant value, clang can check that it is
a power-of-two and within the range of the type. Since the semantics of
these builtins is well defined compared to arbitrary bit-manipulation,
it is possible to add a UBSAN checker that the run-time value is a valid
power-of-two. I intend to add this as a follow-up to this change.
- The builtins avoids int-to-pointer casts both in C and LLVM IR.
In the future (i.e. once most optimizations handle it), we could use the new
llvm.ptrmask intrinsic to avoid the ptrtoint instruction that would normally
be generated.
- They can be used to round up/down to the next aligned value for both
integers and pointers without requiring two separate macros.
- In many projects the alignment operations are already wrapped in macros (e.g.
roundup2 and rounddown2 in FreeBSD), so by replacing the macro implementation
with a builtin call, we get improved diagnostics for many call-sites while
only having to change a few lines.
- Finally, the builtins also emit assume_aligned metadata when used on pointers.
This can improve code generation compared to the uintptr_t casts.

[1] In our CHERI compiler we have compilation mode where all pointers are
implemented as capabilities (essentially unforgeable 128-bit fat pointers).
In our original model, casts from uintptr_t (which is a 128-bit capability)
to an integer value returned the "offset" of the capability (i.e. the
difference between the virtual address and the base of the allocation).
This causes problems for cases such as checking the alignment: for example, the
expression `if ((uintptr_t)ptr & 63) == 0` is generally used to check if the
pointer is aligned to a multiple of 64 bytes. The problem with offsets is that
any pointer to the beginning of an allocation will have an offset of zero, so
this check always succeeds in that case (even if the address is not correctly
aligned). The same issues also exist when aligning up or down. Using the
alignment builtins ensures that the address is used instead of the offset. While
I have since changed the default C semantics to return the address instead of
the offset when casting, this offset compilation mode can still be used by
passing a command-line flag.

Reviewers: rsmith, aaron.ballman, theraven, fhahn, lebedev.ri, nlopes, aqjune
Reviewed By: aaron.ballman, lebedev.ri
Differential Revision: https://reviews.llvm.org/D71499

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