llvm-project

c03d0fe6 - [OpenCL] Add clang internal extension __cl_clang_function_scope_local_variables (#176726)

[OpenCL] Add clang internal extension __cl_clang_function_scope_local_variables (#176726) OpenCL spec restricts that variable in local address space can only be declared at kernel function scope. Add a Clang internal extension __cl_clang_function_scope_local_variables to lift the restriction. To expose static local allocations at kernel scope, targets can either force-inline non-kernel functions that declare local memory or pass a kernel-allocated local buffer to those functions via an implicit argument. Motivation: support local memory allocation in libclc's implementation of work-group collective built-ins, see example at: https://github.com/intel/llvm/blob/41455e305117/libclc/libspirv/lib/amdgcn-amdhsa/group/collectives_helpers.ll https://github.com/intel/llvm/blob/41455e305117/libclc/libspirv/lib/amdgcn-amdhsa/group/collectives.cl#L182 Right now this is a Clang-only OpenCL extension intended for compiling OpenCL libraries with Clang. It could be proposed as a standard OpenCL extension in the future.