[SYCL] Fix compilation warnings in libdevice

[fwyzard]

Apply the DEVICE_EXERNAL attribute also to the function definitions,
not only to the function declarations.

Signed-off-by: Andrea Bocci andrea.bocci@cern.ch

[fwyzard]

Fixes compilation warnings like

In file included from libdevice/fallback-cassert.cpp:9:
libdevice/wrapper.h:16:1: warning: attribute declaration must precede definition [-Wignored-attributes]
DEVICE_EXTERNAL size_t __spirv_GlobalInvocationId_x();
^
libdevice/device.h:28:54: note: expanded from macro 'DEVICE_EXTERNAL'                                                                                                                                                                              
#define DEVICE_EXTERNAL SYCL_EXTERNAL __attribute__((weak))
                                                    ^
libdevice/spirv_vars.hpp:32:29: note: previous definition is here                                                                                                                                                                                  
SYCL_EXTERNAL inline size_t __spirv_GlobalInvocationId_x() {
                           ^

repeated for lines 17, 18, 20, 21, 22.

[fwyzard]

Passes make checl-sycl-devicelib and make check-sycl-cuda-devicelib locally.

[fwyzard]

On the other hand, this breaks building with make sycl-toolchain :-(

[vzakhari]

On the other hand, this breaks building with make sycl-toolchain :-(

I guess this is because spirv_vars.hpp is included before DEVICE_EXTERNAL is defined in device.h :-)

[fwyzard]

I guess this is because spirv_vars.hpp is included before DEVICE_EXTERNAL is defined in device.h :-)

Indeed, including it at the end seems to fix the compilation.

[fwyzard]

I am, however, a bit confused about libdevice:

• device.h makes some check whether it is being used in a "C" or "C++" context; however it includes spirv_vars.hpp which is definitely C++ (use of templates, etc.)
• libdevice doesn't seem to be installed by make deploy-sycl-toolchain
• there is a different (bigger) spirv_vars.hpp under sycl/include/CL/__spirv/

Is libdevice still in fieri ?

[vzakhari]

I am, however, a bit confused about libdevice:

• device.h makes some check whether it is being used in a "C" or "C++" context; however it includes spirv_vars.hpp which is definitely C++ (use of templates, etc.)
• libdevice doesn't seem to be installed by make deploy-sycl-toolchain
• there is a different (bigger) spirv_vars.hpp under sycl/include/CL/__spirv/

Is libdevice still in fieri ?

Yes, it is pretty much WIP, especially after we moved it to toplevel. I am moving spirv_vars.hpp include from device.h to wrapper.h, and making some other clean-up with the goal to minimize dependencies on SYCL. It has to be mostly SPIR library...

I will try deploy-sycl-toolchain, but from what I see here https://github.com/intel/llvm/blob/sycl/sycl/CMakeLists.txt#L292 and here https://github.com/intel/llvm/blob/sycl/libdevice/cmake/modules/SYCLLibdevice.cmake#L163 it has to be deployed.

[fwyzard]

from what I see here https://github.com/intel/llvm/blob/sycl/sycl/CMakeLists.txt#L292 and here https://github.com/intel/llvm/blob/sycl/libdevice/cmake/modules/SYCLLibdevice.cmake#L163 it has to be deployed.

What files should I look for in the installation directory ?

[vzakhari]

from what I see here https://github.com/intel/llvm/blob/sycl/sycl/CMakeLists.txt#L292 and here https://github.com/intel/llvm/blob/sycl/libdevice/cmake/modules/SYCLLibdevice.cmake#L163 it has to be deployed.

What files should I look for in the installation directory ?

Files like these:
install/lib/libsycl-glibc.o
install/lib/libsycl-fallback-cassert.spv

[fwyzard]

Files like these:
install/lib/libsycl-glibc.o
install/lib/libsycl-fallback-cassert.spv

Thanks, then yes, they are installed by make deploy-sycl-toolchain, I see

install/lib64/libsycl-cmath-fp64.o
install/lib64/libsycl-cmath.o
install/lib64/libsycl-complex-fp64.o
install/lib64/libsycl-complex.o
install/lib64/libsycl-fallback-cassert.spv
install/lib64/libsycl-fallback-cmath-fp64.spv
install/lib64/libsycl-fallback-cmath.spv
install/lib64/libsycl-fallback-complex-fp64.spv
install/lib64/libsycl-fallback-complex.spv
install/lib64/libsycl-glibc.o