This implements the result of the discussion at:

https://discourse.llvm.org/t/rfc-report-fatal-error-and-the-default-value-of-gencrashdialog/73587

There are two different use cases for report_fatal_error, so replace it
with two functions reportFatalInternalError() and
reportFatalUsageError(). The former indicates a bug in LLVM and
generates a crash dialog. The latter does not. The names have been
suggested by rnk and people seemed to like them.

This replaces a lot of the usages that passed an explicit value for
GenCrashDiag. I did not bulk replace remaining report_fatal_error usage
-- they probably require case by case review for which function to use.

The module currently stores the target triple as a string. This means
that any code that wants to actually use the triple first has to
instantiate a Triple, which is somewhat expensive. The change in #121652
caused a moderate compile-time regression due to this. While it would be
easy enough to work around, I think that architecturally, it makes more
sense to store the parsed Triple in the module, so that it can always be
directly queried.

For this change, I've opted not to add any magic conversions between
std::string and Triple for backwards-compatibilty purses, and instead
write out needed Triple()s or str()s explicitly. This is because I think
a decent number of them should be changed to work on Triple as well, to
avoid unnecessary conversions back and forth.

The only interesting part in this patch is that the default triple is
Triple("") instead of Triple() to preserve existing behavior. The former
defaults to using the ELF object format instead of unknown object
format. We should fix that as well.

Fixes #99205.

- Implements the HLSL intrinsic `AddUint64` used to perform unsigned
64-bit integer addition by using pairs of unsigned 32-bit integers
instead of native 64-bit types
- The LLVM intrinsic `uadd_with_overflow` is used in the implementation
of `AddUint64` in `CGBuiltin.cpp`
- The DXIL op `UAddc` was defined in `DXIL.td`, and a lowering of the
LLVM intrinsic `uadd_with_overflow` to the `UAddc` DXIL op was
implemented in `DXILOpLowering.cpp`

Notes:
- `__builtin_addc` was not able to be used to implement `AddUint64` in
`hlsl_intrinsics.h` because its `CarryOut` argument is a pointer, and
pointers are not supported in HLSL
- A lowering of the LLVM intrinsic `uadd_with_overflow` to SPIR-V
[already
exists](https://github.com/llvm/llvm-project/blob/main/llvm/test/CodeGen/SPIRV/llvm-intrinsics/uadd.with.overflow.ll)
- When lowering the LLVM intrinsic `uadd_with_overflow` to the `UAddc`
DXIL op, the anonymous struct type `{ i32, i1 }` is replaced with a
named struct type `%dx.types.i32c`. This aspect of the implementation
may be changed when issue #113192 gets addressed
- Fixes issues mentioned in the comments on the original PR #125319

---------

Co-authored-by: Finn Plummer <50529406+inbelic@users.noreply.github.com>
Co-authored-by: Farzon Lotfi <farzonlotfi@microsoft.com>
Co-authored-by: Chris B <beanz@abolishcrlf.org>
Co-authored-by: Justin Bogner <mail@justinbogner.com>

Fixes #112992

This removes "replaceFunctionWithNamedStructOp" and folds its
functionality into "replaceFunctionWithOp". It turns out we were
overcomplicating things and this is trivial to handle generically.

Fixes #113192

- Redefines `DXILAttribute` to denote a function attribute, compatible
to how it was define in DXC/LLVM 3.7
- Fix how `DXILAttribute` is emitted to be a struct of set attributes
instead of an "or" of the enums
- Implement the lowering of `DXILAttribute` to LLVM function attributes
in `DXILOpBuilder.cpp`. A custom mapping is defined.
- Audit all current ops to specify the correct attributes consistent
with DXC. This is done here to allow for testing.
- Update testcases in `llvm/test/CodeGen/DirectX` of all ops with
attributes to match that attributes are set
- Update testcases of ops that had previously incorrectly set attributes
to check there is no attributes set
- Defines `DXILProperty` to denote the other type of attributes from DXC
used to query properties.
- Emit `DXILProperty` as a struct of set attributes.
- Updates `DXIL.td` to specify applicable `DXILProperty`s on ops

Note: `DXILProperty` was referred to as 'queryable attributes' in design
discussion. Changed to property to allow for better expression in
`DXIL.td`

Resolves #114461
Resolves #115912

This introduces `@llvm.dx.resource.load.rawbuffer` and generalizes the
buffer load docs under DirectX/DXILResources.

This resolves the "load" parts of #106188

- Adding hlsl `splitdouble` intrinsics
- Adding DXIL lowering
- Adding SPIRV lowering
- Adding test

Fixes: #108901

---------

Co-authored-by: Joao Saffran <jderezende@microsoft.com>

If the value we're replacing has a name, we might as well preserve it.

The `@llvm.dx.typedBufferLoad` intrinsic is lowered to `@dx.op.bufferLoad`.
There's some complexity here in translating to scalarized IR, which I've
abstracted out into a function that should be useful for samples, gathers, and
CBuffer loads.

I've also updated the DXILResources.rst docs to match what I'm doing here and
the proposal in llvm/wg-hlsl#59. I've removed the content about stores and raw
buffers for now with the expectation that it will be added along with the work.

Note that this change includes a bit of a hack in how it deals with
`getOverloadKind` for the `dx.ResRet` types - we need to adjust how we deal
with operation overloads to generate a table directly rather than proxy through
the OverloadKind enum, but that's left for a later change here.

Part of #91367

Pull Request: https://github.com/llvm/llvm-project/pull/104252