This is an experimental address space for strided buffers. These buffers
can have structs as elements and
a stride > 1.
These pointers allow the indexed access in units of stride, i.e., they
point at `buffer[index * stride]`.
Thus, we can use the `idxen` modifier for buffer loads.
We assign address space 9 to 192-bit buffer pointers which contain a
128-bit descriptor, a 32-bit offset and a 32-bit index. Essentially,
they are fat buffer pointers with an additional 32-bit index.
Before we tracked the size of the teams reduction buffer in order to
allocate it at runtime per kernel launch. This patch splits the number
into two parts, the size of the reduction data (=all reduction
variables) and the (maximal) length of the buffer. This will allow us to
allocate less if we need less, e.g., if we have less teams than the
maximal length. It also allows us to move code from clangs codegen into
the runtime as we now know how large the reduction data is.
The KernelEnvironment is for compile time information about a kernel. It
allows the compiler to feed information to the runtime. The
KernelLaunchEnvironment is for dynamic information *per* kernel launch.
It allows the rutime to feed information to the kernel that is not
shared with other invocations of the kernel. The first use case is to
replace the globals that synchronize teams reductions with per-launch
versions. This allows concurrent teams reductions. More uses cases will
follow, e.g., per launch memory pools.
Fixes: https://github.com/llvm/llvm-project/issues/70249
This reverts commit ddbaa11e9f43a38d50d62a9b9b07c3653b6bf8ab.
Reapply the original commit, the broken test was repaired in 5e51363f38d083ab326736c0d4d1b5f9fe0de080 in the meantime.
The runtime needs to know about the acceptable launch bounds, especially
if the compiler (middle- or backend) assumed those bounds. While this
patch does not yet inform the runtime, it stores the bounds in a place
that can/will be accessed and is associated with the kernel.
When other AAs query the current value of KernelEnvC via the callback
KernelConfigurationSimplifyCB we need to ensure they are now dependent
on the AAKernelInfo that is in charge of the KernelEnvC.