[Bug target/70216] [SH] Implement __builtin_trap

[olegendo at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70216

--- Comment #6 from Oleg Endo <olegendo at gcc dot gnu.org> ---
Created attachment 38083
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38083&action=edit
Proposed patch

This patch adds two new target options:
  -msh4-trapa-sleep-bug
  -mbuiltin-trap=

and two configure options:
  --with-builtin-trap
  --enable-sh4-trapa-sleep-bug / --disable-sh4-trapa-sleep-bug

On sh*-linux it should configure itself to use -mbuiltin-trap=trapa,imm=84 by
default.

I'm not sure if the -msh4-trapa-sleep-bug should be enabled by default on
sh*-linux to always emit the workaround insn sequence (trap + 5x or r0,r0).  If
--enable-sh4-trapa-sleep-bug is not specified, it will only be enabled when
compiling code for SH4.