[PATCH] D51544: [OpenCL] Split opencl-c.h header

[Anastasia Stulova via Phabricator via cfe-commits]

Anastasia added a comment.

In https://reviews.llvm.org/D51544#1227336, @asavonic wrote:

> In https://reviews.llvm.org/D51544#1227313, @Anastasia wrote:
>
> > Currently the main header still contains everything, so the size of the PCH won't change.
>
>
> The idea is that we don't pre-compile the whole opencl-c.h, we split
>  it into several headers (3 of them are target independent) and
>  pre-compile them instead.
>
> With this approach, we can reuse target-independent PCHs (common,
>  fp16, fp64) and only duplicate target-specific PCHs if needed
>  (opencl-c-platform.h).
>
> The idea is basically:
>
> 1. Compile target-independent headers into modules:
>   - opencl-c-common.h -> opencl-c-common.pcm
>   - opencl-c-fp16.h -> opencl-c-fp16.pcm
>   - opencl-c-fp64.h -> opencl-c-fp64.pcm
> 2. Implicitly include opencl-c.h (plain header), which has the following content:
>
>
>
>   #include "opencl-c-common.h"
>   #if cl_khr_fp16
>   #include "opencl-c-fp16.h"
>   #endif
>   #if cl_khr_fp64
>   #include "opencl-c-fp16.h"
>   #endif
>   #include "opencl-c-platform.h"
>   
>
> When compiler reaches an #include statement in opencl-c.h, it loads a
>  corresponding PCH. Headers that were not pre-compiled are included as
>  usual.


Ok, I see. It seems reasonable. I am not sure if `opencl-c-platform` is the right name, since it seems some of the bits are just version/extension dependent there and not the platform? But perhaps if you add some description with guidelines on what should be put in each header, it should be fine.


Repository:
  rC Clang

https://reviews.llvm.org/D51544