[PATCH] [Builtins] Implement half-precision conversions.

[Ahmed Bougacha]

Hi scanon,

Mostly uninteresting, except:

- in __extendXfYf2, when checking if the number is normal, the current code relies on the unsignedness of src_rep_t, which is fine.  Except that when sizeof(src_rep_t) < sizeof(int), the result gets promoted to int, the signedness of which breaks the comparison.  I added an explicit cast to avoid that;  it shouldn't affect other types.

- we can't just pass __fp16 around (you even get a clang error), so I made uint16_t explicit.

- is there a good way to define aliases (for the gnu_*_ieee names) ?  Using the attribute, on darwin, clang complains about only weak aliases being supported, so I went with the simple def.


I also need to finish writing unit tests in compiler-rt proper (I paused when I realized lit+cmake isn't supported).  In the meantime, opinions welcome.

http://reviews.llvm.org/D9693

Files:
  lib/builtins/CMakeLists.txt
  lib/builtins/extendhfsf2.c
  lib/builtins/fp_extend.h
  lib/builtins/fp_extend_impl.inc
  lib/builtins/fp_trunc.h
  lib/builtins/truncdfhf2.c
  lib/builtins/truncsfhf2.c

EMAIL PREFERENCES
  http://reviews.llvm.org/settings/panel/emailpreferences/
-------------- next part --------------
A non-text attachment was scrubbed...
Name: D9693.25541.patch
Type: text/x-patch
Size: 5194 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20150512/7c377682/attachment.bin>