Changes

[AArch64] Fix over-eager fusing of NEON SIMD MUL/ADD
Summary: The ISel pattern for SIMD MLA is a bit too eager: it replaces
the ADD with an MLA even when the MUL cannot be eliminated, e.g. when it
has another use.  An MLA is usually has a higher latency than an ADD
(and there are fewer pipes available that can execute it), so trading an
MLA for an ADD is not great.
ISel is not taking the number of uses of the MUL result into account,
nor any other factors such as the length of the critical path or other
resource pressure.
The MachineCombiner is able to make these judgments so this patch ports
the ISel pattern for MUL/ADD fusing to the MachineCombiner.
Similarly for MUL/SUB -> MLS, as well as the indexed variants.
The change has no impact on SPEC CPU© intrate nor fprate.
Reviewers: dmgreen, SjoerdMeijer, fhahn, Gerolf
Subscribers: kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70673

[lldb/Reproducer] Add version check
To ensure a reproducer works correctly, the version of LLDB used for 
capture and replay must match. Right now the reproducer already contains 
the LLDB version. However, this is purely informative. LLDB will happily 
replay a reproducer generated with a different version of LLDB, which 
can cause subtle differences.
This patch adds a version check which compares the current LLDB version 
with the one in the reproducer. If the version doesn't match, LLDB will 
refuse to replay. It also adds an escape hatch to make it possible to 
still replay the reproducer without having to mess with the recorded 
version. This might prove useful when you know two versions of LLDB 
match, even though the version string doesn't. This behavior is 
triggered by passing a new flag -reproducer-skip-version-check to the 
lldb driver.
Differential revision: https://reviews.llvm.org/D70934

[OpenCL] Use generic addr space for lambda call operator
Since lambdas are represented by callable objects, we add generic addr
space for implicit object parameter in call operator.
Any lambda variable declared in __constant addr space
(which is not convertible to generic) fails to compile with a
diagnostic. To support constant addr space we need to add a way to
qualify the lambda call operators.
Tags: #clang
Differential Revision: https://reviews.llvm.org/D69938

[EditLine] Fix RecallHistory to make it go in the right direction.
The naming used by editline for the history operations is counter 
intuitive to how it's used in lldb for the REPL.
 - The H_PREV operation returns the previous element in the history,
  which is newer than the current one.
- The H_NEXT operation returns the next element in the history, which
  is older than the current one.
This exposed itself as a bug in the REPL where the behavior of up- and 
down-arrow was inverted. This wasn't immediately obvious because of how 
we save the current "live" entry.
This patch fixes the bug and introduces and enum to wrap the editline 
operations that match the semantics of lldb.
Differential revision: https://reviews.llvm.org/D70932

[SYCL] Add sycl_kernel attribute for accelerated code outlining
SYCL is single source offload programming model relying on compiler to 
separate device code (i.e. offloaded to an accelerator) from the code 
executed on the host.
Here is code example of the SYCL program to demonstrate compiler 
outlining work:
``` int foo(int x) { return ++x; } int bar(int x) { throw
std::exception("CPU code only!"); }
... using namespace cl::sycl; queue Q; buffer<int, 1> a(range<1>{1024}); 
Q.submit([&](handler& cgh) {
 auto A = a.get_access<access::mode::write>(cgh);
 cgh.parallel_for<init_a>(range<1>{1024}, [=](id<1> index) {
   A[index] = index[0] + foo(42);
 });
}
...
```
SYCL device compiler must compile lambda expression passed to 
cl::sycl::handler::parallel_for method and function foo called from this 
lambda expression for an "accelerator". SYCL device compiler also must 
ignore bar function as it's not required for offloaded code execution.
This patch adds the sycl_kernel attribute, which is used to mark code 
passed to cl::sycl::handler::parallel_for as "accelerated code".
Attribute must be applied to function templates which parameters include 
at least "kernel name" and "kernel function object". These parameters 
will be used to establish an ABI between the host application and 
offloaded part.
Reviewers: jlebar, keryell, Naghasan, ABataev, Anastasia, bader,
aaron.ballman, rjmccall, rsmith
Reviewed By: keryell, bader
Subscribers: mgorny, OlegM, ArturGainullin, agozillon, aaron.ballman,
ebevhan, Anastasia, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D60455
Signed-off-by: Alexey Bader <alexey.bader@intel.com>