Changes

[test] Split some tests which test both static and pic relocation models

TargetMachine::shouldAssumeDSOLocal currently implies dso_local for
Static. Split some tests so that these `external dso_local global`
will align with the Clang behavior.

[TargetMachine] Don't imply dso_local on global variable declarations in Reloc::Static model

clang/lib/CodeGen/CodeGenModule sets dso_local on applicable global variables,
we don't need to duplicate the work in TargetMachine:shouldAssumeDSOLocal.
(Actually the long-term goal (started by r324535) is to remove as much
additional implied dso_local in TargetMachine:shouldAssumeDSOLocal as possible.)

By not implying dso_local, we will respect dso_local/dso_preemptable specifiers
set by the frontend. This allows the proposed -fno-direct-access-external-data
option to work with -fno-pic and prevent copy relocations.

This patch should be NFC in terms of the Clang behavior because the case we
don't set dso_local is a case Clang sets dso_local. However, some tests don't
set dso_local on some `external global` and expose some differences. Most tests
have been fixed to be more robust in previous commits.

[ELF] Fix relocation-model.ll

[lldb] Remove unused argument to expectedFailure

[debugserver] Honor the cpu sub type if specified

Use the newly added spawnattr API, posix_spawnattr_setarchpref_np, to
select a slice preferences per cpu and subcpu types, instead of just cpu
with posix_spawnattr_setarchpref_np.

rdar://16094957

Differential revision: https://reviews.llvm.org/D92712

[builtins][ARM] Check __ARM_FP instead of __VFP_FP__.

This patch fixes builtins' CMakeLists.txt and their VFP tests to check
the standard macro defined in the ACLE for VFP support. It also enables
the tests to be built and run for single-precision-only targets while
builtins were built with double-precision support.

Differential revision: https://reviews.llvm.org/D92497

[mlir][OpFormatGen] Add support for optional enum attributes

The check for formatting enum attributes was missing a call to get the base attribute, which is necessary to strip off the top-level OptionalAttr<> wrapper.

Differential Revision: https://reviews.llvm.org/D92713

[mlir][IR] Move the storage for results to before the Operation instead of after.

Trailing objects are really nice for storing additional data inline with the main class, and is something that we heavily take advantage of for Operation(and many other classes). To get the address of the inline data you need to compute the address by doing some pointer arithmetic taking into account any objects stored before the object you want to access. Most classes keep the count of the number of objects, so this is relatively cheap to compute. This is not the case for results though, which have two different types(inline and trailing) that are not necessarily as cheap to compute as the count for other objects. This revision moves the storage for results to before the operation and stores them in reverse order. This allows for getting results to still be very fast given that they are never iterated directly in order, and also greatly improves the speed when accessing the other trailing objects of an operation(operands/regions/blocks/etc).

This reduced compile time when compiling a decently sized mlir module by about ~400ms, or 2.17s -> 1.76s.

Differential Revision: https://reviews.llvm.org/D92687

[RISCV] Formatting for easier reading (NFC)

Authored-by: Hsiangkai Wang <kai.wang@sifive.com>