stores/insertelement instructions, NFC.

Reverts llvm/llvm-project#75882

To recover build bots :
https://lab.llvm.org/buildbot/#/builders/239/builds/5361
https://lab.llvm.org/buildbot/#/builders/168/builds/18126

This patch make vsetvl insertion pass could track the number of
inserted/removed vsetvl instruction from `-stats` option.

This adds minimal support for 7 new unprivileged extensions that were
defined as a part of
the RISC-V Profiles specification here:

https://github.com/riscv/riscv-profiles/blob/main/profiles.adoc#7-new-isa-extensions

* Ziccif: Main memory supports instruction fetch with atomicity
requirement
* Ziccrse: Main memory supports forward progress on LR/SC sequences
* Ziccamoa: Main memory supports all atomics in A
* Zicclsm: Main memory supports misaligned loads/stores
* Za64rs: Reservation set size of 64 bytes
* Za128rs: Reservation set size of 128 bytes
* Zic64b: Cache block size isf 64 bytes

As stated in the specification, these extensions don't add any new
features but
describe existing features. So this patch only adds parsing and
subtarget
features.

Also convert from std::vector to SmallVector.

This matches the ELF linker where these were moved into the ctx object
in 9a572164 and converted to SmallVector in ba948c5a.

These cause test build failures on Windows.

This reverts the following commits:
  57ca7484
  d06ae33e

This ports msan https://reviews.llvm.org/D14795 to dfsan.
dfsan, like msan, clears shadow for globals in a newly opened DSO in
case the DSO occupies the address of a previously labeled/poisoned area.
The operation should not happen on the main executable.

In addition, for a DT_EXEC executable, l_addr is zero and will lead to a
null pointer dereference in ForEachMappedRegion.

See lld/ELF/Config.h

The lifetime of these BreakpointEventData objects is difficult to reason
about. These BreakpointEventData pointers are created and passed along
to `Event` which takes the raw pointer and sticks them in a shared
pointer. Instead of manually managing the lifetime and memory, it would
be simpler to have them be shared pointers from the start.

Make output function addresses be delta-encoded wrt last offset in the
previous function. This reduces the deltas in function start addresses.

Test Plan:
Reduces BAT section size to:
- large binary: 12218860 bytes (0.32x original),
- medium binary: 1606580 bytes (0.27x original),
- small binary: 404 bytes (0.28x original),

Reviewers: rafaelauler

Reviewed By: rafaelauler

Pull Request: https://github.com/llvm/llvm-project/pull/76904

32-bit x86 doesn't have an appropriate relocation type we can use to
elide the RTTI proxies, so we need to emit them. This would previously
cause crashes when using the relative vtable ABI for 32-bit x86.

`new` was introduced in this patch, but I don't see `delete` to release
the memory.

In .new instructions, the upper vector of a reverse pair (e.g. V4 in
V4:5) should be referenced with an odd sss value.

Summary:
A recent patch in https://github.com/llvm/llvm-project/pull/72280
provided `clang` the ability to easily use scoped atomics. These are a
special modifier on atomics that some backends support. They are
intended for providing more fine-grained control over the affected
memory of an atomic action. The default is a "system" scope, e.g.
coherence with the GPU and CPU memory on a heterogeneous system. If we
use "device" scope, that implies that the memory is only ordered with
respect to the current GPU.

These builtins are direct replacements for the GCC atomic builitins in
cases where the backend doesn't do anything with the information, so
these should be a drop-in. This introduces some noise, but hopefully it
isn't too contentious.

std:: usually is not a cause of the bug.

We now display 
```
SUMMARY: AddressSanitizer: allocation-size-too-big path/to/allocator_returns_null.cpp:92:7 in main
```
instead of 

```
SUMMARY: AddressSanitizer: allocation-size-too-big /usr/lib/../include/c++/13/bits/new_allocator.h:147:27 in std::__new_allocator<char>::allocate(unsigned long, void const*)
```

`/include/c++/` matches both libc++ and libstdc++ include paths.

For example, the following message has the severity string "error: "
twice.
	> "error: <EXPR>:3:1: error: cannot find 'bogus' in scope

This method already appends the severity string in the beginning, but
with this fix, it also removes a secondary instance, if applicable.

Note that this change only removes the *first* redundant substring. I
considered putting the removal logic in a loop, but I decided that if
something is generating more than one redundant severity substring, then
that's a problem the message's source should probably fix.

rdar://114203423

This is another follow-up to f4fbbebb and 30da0f5a

explicitly pass libLTO path. This fixes a failure in swift-ci where
libLTO was being picked from the system instead which was an older
version and caused issues.

rdar://117474861

This reverts commit cb67dc19.

Add a clang flag, "-ftrivial-auto-var-init-max-size=" so that clang
skips auto-init a variable if the auto-init memset size exceeds the flag
setting (in bytes). Note that this skipping doesn't apply to
runtime-sized variables like VLA.

Considerations: "__attribute__((uninitialized))" can be used to manually
opt variables out. However, there are thousands of large variables
(e.g., >=1KB, most of them are arrays and used as buffers) in big
codebase. Manually opting them out one by one is not efficient.

Don't put \uXXXX escapes into the cooked character stream while
prescanning; it should always be UTF-8.

This fixes some cases of missing debuginfo caused by an interaction
between:


https://github.com/llvm/llvm-project/commit/f0d66559ea345db4b2116cae044aaf3399d7e829,
which drops the identifier from a DICompositeType in the module
containing its
vtable.

and


https://github.com/llvm/llvm-project/commit/a61f5e379675732666744bcba25efbc9922e016a,
which causes ThinLTO to import composite types as declarations when they
have
an identifier.

If a virtual class's DICompositeType has no identifier due to the first
change,
and contains a nested anonymous type which does have an identifier, then
the
second change can cause ThinLTO to output the classes's DICompositeType
as a
type definition that links to a non-defining declaration for the nested
type.
Since the nested anonyous type does not have a name, debuggers are
unable to
find the definition for the declaration.

Repro case:
```
cat > a.h <<EOF
class A {
 public:
  A();
  virtual ~A();

 private:
  union {
    int val;
  };
};
EOF

cat > a.cc <<EOF
#include "a.h"

A::A() { asm(""); }

A::~A() {}
EOF

cat > main.cc <<EOF
#include "a.h"

int main(int argc, char **argv) {
  A a;
  return 0;
}
EOF

clang++ -O2 -g -flto=thin -mllvm -force-import-all main.cc a.cc
gdb ./a.out -batch -ex 'pt /rmt A'
```

The gdb command outputs:
```
type = class A {
  private:
    union {
        <incomplete type>
    };
}
```

and dwarfdump -i a.out shows a DW_TAG_class_type for A with an
incomplete union
type (note that there is also a duplicate entry with the full union type
that
comes after).
```
< 1><0x0000001e>    DW_TAG_class_type
                      DW_AT_containing_type       <0x0000001e>
                      DW_AT_calling_convention    DW_CC_pass_by_reference
                      DW_AT_name                  (indexed string: 0x00000007)A
                      DW_AT_byte_size             0x00000010
                      DW_AT_decl_file             0x00000001 /path/to/./a.h
                      DW_AT_decl_line             0x00000001
...
< 2><0x0000002f>      DW_TAG_member
                        DW_AT_type                  <0x00000037>
                        DW_AT_decl_file             0x00000001 /path/to/./a.h
                        DW_AT_decl_line             0x00000007
                        DW_AT_data_member_location  8
< 2><0x00000037>      DW_TAG_union_type
                        DW_AT_export_symbols        yes(1)
                        DW_AT_calling_convention    DW_CC_pass_by_value
                        DW_AT_declaration           yes(1)
```

This change works around this by making ThinLTO always import full
definitions
for anonymous types.

[openmp] Revert 64874e5a since it was committed by mistake and the PR (https://github.com/llvm/llvm-project/pull/77853) wasn't approved yet.

This bug is caused by parenthesized list initialization not being
implemented in `CodeGenFunction::EmitNewArrayInitializer(...)`.

Parenthesized list initialization of `struct`s with `operator new`
already works in Clang and is not affected by this bug.

Additionally, fix the test new-delete.cpp as it incorrectly assumes that
using parentheses with operator new to initialize arrays is illegal for
C++ versions >= C++17.

Fixes #68198

This commit corrects the address computation for objc_msgSend stubs.
Previously, the address computation was incidentally correct due to
objc_msgSend often being the first entry in the got section, resulting
in a 0 index. This commit ensures accurate address computation
regardless of the objc_msgSend stub's position in the got section.

Fixes `SmallString` summary provider, which was incorrectly producing the empty string. 
Initially I thought the strings I was debugging were empty for unknown reasons, but 
that was not the case.

This is inspired by
https://github.com/llvm/llvm-project/pull/77342#pullrequestreview-1814673242,
and is split off of same with some differences in style.

A select is a vmerge.vv with the additional cost of materializing the
bitmask vector in a vreg. All masks fit within a single vector register
(e8 + m8 is the worst case), and thus our worst case cost should be
roughly 3 (2 scalar to produce the address, one vector load op). Given
most shuffles are small, and the mask will be instead produced by
LUI/ADDI + vmv.s.x or ADDI + vmv.s.x, using 2 as the default seems quite
reasonable. At worst, we're not going to be off by much.

The prior lowering scaled the cost of the bitmask with LMUL, which I
don't understand. At m1 it did use the same base cost of 2. (@lukel97
You wrote the original code here, anything I'm missing here?)

Fixes:
```
[13/270] Building CXX object tools\lldb\unittests\Core\CMakeFiles\LLDBCoreTests.dir\DumpDataExtractorTest.cpp.obj
C:\git\llvm-project\lldb\unittests\Core\DumpDataExtractorTest.cpp(140): warning C4305: 'argument': truncation from 'double' to 'const std::complex<float>::_Ty'
```

Fixes several of these:
```
[3370/3822] Building CXX object tools\lldb\source\Plugins\Process\U...lldbPluginProcessUtility.dir\NativeRegisterContextDBReg_x86.cpp.ob
C:\git\llvm-project\lldb\source\Plugins\Process\Utility\NativeRegisterContextDBReg_x86.h(23): warning C4589: Constructor of abstract class 'lldb_private::NativeRegisterContextDBReg_x86' ignores initializer for virtual base class 'lldb_private::NativeRegisterContextRegisterInfo'
C:\git\llvm-project\lldb\source\Plugins\Process\Utility\NativeRegisterContextDBReg_x86.h(23): note: virtual base classes are only initialized by the most-derived type
```

Fixes:
```
[3465/3822] Building CXX object tools\lldb\source\Plugins\SymbolFile\CTF\CMakeFiles\lldbPluginSymbolFileCTF.dir\SymbolFileCTF.cpp.obj
C:\git\llvm-project\lldb\source\Plugins\SymbolFile\CTF\SymbolFileCTF.cpp(606) : warning C4715: 'lldb_private::SymbolFileCTF::CreateType': not all control paths return a value
```