Reverts llvm/llvm-project#80890

Currently, a method exists to get the count of the operation objects
which are still alive. This helps for sanity checking, but isn't
terribly useful for debugging. This new method returns the actual
operation objects which are still alive.

This allows Python code like the following:

```
    gc.collect()
    live_ops = ir.Context.current._get_live_operation_objects()
    for op in live_ops:
      print(f"Warning: {op} is still live. Referrers:")
      for referrer in gc.get_referrers(op)[0]:
        print(f"  {referrer}")
```

1. Add parsing methods for block[n, m].
2. Encode n and m with the newly extended 64-bit LevelType enum.
3. Update 2:4 methods names/comments to n:m.

Add a SPIR-V target-specific intrinsic for creating handles, which is
used for lowering HLSL resources types like RWBuffer.

`llvm/lib/TargetParser/Triple.cpp`: SPIR-V intrinsics use "spv" as the
target prefix, not "spirv". As far as I can tell, this is the first one
that is used via the `CGBuiltin` codepath, which relies on
`getArchTypePrefix`, so I've corrected it here.

`clang/lib/Basic/Targets/SPIR.h`: When records are laid out in the
lowering from AST to IR, they were incorrectly offset because these
Pointer attributes were defaulting to 32.

Related to #81036

Fixes https://github.com/llvm/llvm-project/issues/80910.

Per the documentation in ISDOpcodes.h, for BUILD_VECTOR "The types of
the operands must match the vector element type, except that integer
types are allowed to be larger than the element type, in which case the
operands are implicitly truncated."

This transform was assuming that the scalar operand type matched the
result type. This resulted in essentially performing a truncate before a
binop, instead of after. As demonstrated by the test case changes, this
is often not legal.

[AMDGPU] Compiler should synthesize private buffer resource descriptor from flat_scratch_init (#79586)

This change implements synthesizing the private buffer resource
descriptor in the kernel prolog instead of using the preloaded kernel
argument.

LLDB has a setting (symbols.enable-background-lookup) that calls
dsymForUUID on a background thread for images as they appear in the
current backtrace. Originally, the laziness of only looking up symbols
for images in the backtrace only existed to bring the number of
dsymForUUID calls down to a manageable number.

Users have requesting the same functionality but blocking. This gives
them the same user experience as enabling dsymForUUID globally, but
without the massive upfront cost of having to download all the images,
the majority of which they'll likely not need.

This patch renames the setting to have a more generic name
(symbols.auto-download) and changes its values from a boolean to an
enum. Users can now specify "off", "background" and "foreground". The
default remains "off" although I'll probably change that in the near
future.

The following test case in
`clang-tools-extra/test/clang-tidy/infrastructure/diagnostic.cpp` is
failing:
```
#ifdef PR64602 // Should not crash
template <class T = void>
struct S
{
    auto foo(auto);
};

template <>
auto S<>::foo(auto)
{
    return 1;
}
// CHECK8: error: template parameter list matching the non-templated nested type 'S<>' should be empty ('template<>') [clang-diagnostic-error]
#endif
```

#80864 fixes a bug where we would (incorrectly) append invented template
parameters to empty template parameter lists, which causes this test to
fail.

The MemoryBuffer is created using `RequiresNullTerminator`, so we can
safely skip the `CurPtr != CurBuf.end()` check. The redundant check
causes a cppcheck report. In addition, elsewhere, including `*CurPtr ==
'#'` below, makes the null terminator assumption as well.

Close #81120

This commit adds a new broadcast bit to the debugger. When in use, it
will be listened to for progress events that will be delivered and kept
track of by category as opposed to the current behaviour of coming in
one by one.

Both LLVM_LINK_LLVM_DYLIB and LLVM_PARALLEL_LINK_JOBS help with some
common gotchas. It seems worth documenting them here explicitly.

Based on a review comment, also "refactor" the documentation to avoid duplication.

This reduces the time to include `<compare>` from 84ms to 36ms.

The cv specializations for `numeric_limits` inherited privately for some
reason. We can simplify the implementation by inheriting publicly and
removing the members that just replicate the values from the base class.

This reverts commit bdde5f9b.

Two situations that are tripping a few buildbots:

  https://lab.llvm.org/buildbot/#/builders/205/builds/25126

Here, polly is currently presenting a DebugLoc attached to a debugging
intrinsic as a "true" source location in a user report, something that's
unreliable.

  https://lab.llvm.org/buildbot/#/builders/184/builds/10242

These HWAsan failures are probably (97% confidence) because in
StackInfoBuilder::visit we're not observing DPValues attached to lifetime
intrinsics because they're delt with higher up the function.

But it's late-o'clock here, so revert for now.

This patch provides more information to the
`PPCallbacks::InclusionDirective()` hook. We now always pass the
suggested module, regardless of whether it was actually imported or not.
The extra `bool ModuleImported` parameter then denotes whether the
header `#include` will be automatically translated into import the the
module.

The main change is in `clang/lib/Lex/PPDirectives.cpp`, where we take
care to not modify `SuggestedModule` after it's been populated by
`LookupHeaderIncludeOrImport()`. We now exclusively use the `SM`
(`ModuleToImport`) variable instead, which has been equivalent to
`SuggestedModule` until now. This allows us to use the original
non-modified `SuggestedModule` for the callback itself.

(This patch turns out to be necessary for
https://github.com/apple/llvm-project/pull/8011).

[Clang][Sema] Abbreviated function templates do not append invented parameters to empty template parameter lists (#80864)

According to [dcl.fct] p23:
> An abbreviated function template can have a _template-head_. The
invented _template-parameters_ are appended to the
_template-parameter-list_ after the explicitly declared
_template-parameters_.

`template<>` is not a _template-head_ -- a _template-head_ must have at
least one _template-parameter_. This patch corrects our current behavior
of appending the invented template parameters to the innermost template
parameter list, regardless of whether it is empty. Example:
```
template<typename T>
struct A 
{ 
    void f(auto); 
};

template<>
void A<int>::f(auto); // ok

template<>
template<> // warning: extraneous template parameter list in template specialization
void A<int>::f(auto);
```

This is a first simple patch to introduce a new FIR attribute to carry
the CUDA variable attribute information to hlfir.declare and fir.declare
operations. It currently lowers this information for local variables.

The texture attribute is omitted since it is rejected by semantic and
will not make its way to MLIR.

This new attribute is added as optional attribute to the hlfir.declare
and fir.declare operations.

Match DXIL TableGen class names with structure names in DXIL Emitter. 
Delete unnecessary Name field.

Fixes #55106

In HLSL bit shifts are defined to shift by shift size % type size. This
contains the following changes:

HLSL codegen bit shifts will be emitted as x << (y & (sizeof(x) - 1) and
bitshift masking leverages the OpenCL pipeline for this.

Tests were also added to validate this behavior.


Before this change the following was being emitted:
; Function Attrs: noinline nounwind optnone
define noundef i32 @"?shl32@@YAHHH@Z"(i32 noundef %V, i32 noundef %S) #0
{
entry:
  %S.addr = alloca i32, align 4
  %V.addr = alloca i32, align 4
  store i32 %S, ptr %S.addr, align 4
  store i32 %V, ptr %V.addr, align 4
  %0 = load i32, ptr %V.addr, align 4
  %1 = load i32, ptr %S.addr, align 4
  %shl = shl i32 %0, %1
  ret i32 %shl
}

After this change:
; Function Attrs: noinline nounwind optnone
define noundef i32 @"?shl32@@YAHHH@Z"(i32 noundef %V, i32 noundef %S) #0
{
entry:
  %S.addr = alloca i32, align 4
  %V.addr = alloca i32, align 4
  store i32 %S, ptr %S.addr, align 4
  store i32 %V, ptr %V.addr, align 4
  %0 = load i32, ptr %V.addr, align 4
  %1 = load i32, ptr %S.addr, align 4
  %shl.mask = and i32 %1, 31
  %shl = shl i32 %0, %shl.mask
  ret i32 %shl
}

---------

Co-authored-by: Cooper Partin <coopp@ntdev.microsoft.com>

This is a reduced test case for a fix for the issue identified in
https://github.com/llvm/llvm-project/issues/80910.

[X86] X86FixupVectorConstants - use explicit register bitwidth for the loaded vector instead of using constant pool bitwidth

Fixes #81136 - we might be loading from a constant pool entry wider than the destination register bitwidth, affecting the vextload scale calculation.

ConvertToBroadcastAVX512 doesn't yet set an explicit bitwidth (it will default to the constant pool bitwidth) due to difficulties in looking up the original register width through the fold tables, but as we only use rebuildSplatCst this shouldn't cause any miscompilations, although it might prevent folding to broadcast if only the lower bits match a splatable pattern.

Refactors logic in `ParseInternal` that was previously calling
`GetFormatFromCString` twice, once with `partial_match_ok` set to false,
and the second time set to true.

With this change, lldb formats (ie `%@`, `%S`, etc) are checked first.
If a format is not one of those, then `GetFormatFromCString` is called
once, and now always checks for partial matches.

This formatter
https://github.com/llvm/llvm-project/pull/78609
was originally passing the signed seconds (which can refer to times in
the past) with an unsigned printf formatter, and had tests that expected
to see negative values from the printf which always failed on macOS. I'm
not clear how they ever passed on any platform.

Fix the printf to print seconds as a signed value, and re-enable the
tests.

This patch causes all variable-location debug-info to be converted into
non-intrinsic records as they passes through the optimisation /
instrumentation passes. There's a brief introduction here [0] and a more
detailed thread on what this means on discourse at [1].

If this commit is breaking your downstream tests, please see comment 12 in
[1], which documents the kind of variation in tests we'd expect to see from
this change and what to do about it.

[0] https://llvm.org/docs/RemoveDIsDebugInfo.html
[1] https://discourse.llvm.org/t/rfc-instruction-api-changes-needed-to-eliminate-debug-intrinsics-from-ir/68939

In #80317 the data op generation was updated to use correctly the #0
result from the hlfir.delcare op. In case of optional that are not
descriptor, it is preferable to use the original input for the varPtr
value of the OpenACC data op.
This patch also make sure that the descriptor value of optional is only
accessed when present.

XCOFF encodes a symbol type and alignment in a single 8-bit field. It is
easier to read and write YAML files if the fields can be specified
separately. This PR causes obj2yaml to write the fields separately and
allows yaml2obj to read either the single combined field or the separate
fields.

Make it clearer that this refers to the width of the constant element stored in memory - which won't match the register element width after a sext/zextload

[X86] X86FixupVectorConstants - add destination register width to rebuildSplatCst/rebuildZeroUpperCst/rebuildExtCst callbacks

As found on #81136 - we aren't correctly handling for cases where the constant pool entry is wider than the destination register width, causing incorrect scaling of the truncated constant for load-extension cases.

This first patch just pulls out the destination register width argument, its still currently driven by the constant pool entry but that will be addressed in a followup.

A colleague observes that switching the default value of
LLVM_EXPERIMENTAL_DEBUGINFO_ITERATORS to "On" hasn't flipped the value
in their CMakeCache.txt. This probably means that everyone with an
existing build tree is going to not have support built in, meaning
everyone in LLVM would need to clean+rebuild their worktree when we flip
the switch on... which doesn't sound good.

So instead, just delete the flag and everything it does, making everyone
build and run ~400 lit tests in RemoveDIs mode. None of the buildbots
have had trouble with this, so it Should Be Fine (TM).

(Sending for review as this is changing various comments, and touches
several different areas -- I don't want to get too punchy).

Collection of changes with the goal of being able to convert `encoding`
to `memorySpace` during bufferization
- new API for encoder to allow implementation to select destination
memory space
- update existing bufferization implementations to support the new
interface