| Age | Commit message (Collapse) | Author | Lines |
|---|
|
Update atomic.h to provide a_ctz_l in all cases (atomic_arch.h should
now only provide a_ctz_32 and/or a_ctz_64).
The generic version of a_ctz_32 now takes advantage of a_clz_32 if
available and the generic a_ctz_64 now makes use of a_ctz_32.
|
|
counts leading zero bits of a 64bit int, undefined on zero input.
(has nothing to do with atomics, added to atomic.h so target specific
helper functions are together.)
there is a logarithmic generic implementation and another in terms of
a 32bit a_clz_32 on targets where that's available.
|
|
commits e24984efd5c6ac5ea8e6cb6cd914fa8435d458bc and
16b55298dc4b6a54d287d7494e04542667ef8861 inadvertently disabled the
a_spin implementations for i386, x86_64, and x32 by defining a macro
named a_pause instead of a_spin. this should not have caused any
functional regression, but it inhibited cpu relaxation while spinning
for locks.
bug reported by George Kulakowski.
|
|
this commit mostly makes consistent things like spacing, function
ordering in atomic_arch.h, argument names, use of volatile, etc. the
fake 64-bit and/or atomics are also removed because the shared
atomic.h does a better job of implementing them; it avoids making two
atomic memory accesses when only one 32-bit half needs to be touched.
no major overhaul is needed or possible because x86 actually has
native versions of all the usual atomic operations, rather than using
ll/sc or needing cas loops.
|
|
rather than having each arch provide its own atomic.h, there is a new
shared atomic.h in src/internal which pulls arch-specific definitions
from arc/$(ARCH)/atomic_arch.h. the latter can be extremely minimal,
defining only a_cas or new ll/sc type primitives which the shared
atomic.h will use to construct everything else.
this commit avoids making heavy changes to the individual archs'
atomic implementations. definitions which are identical or
near-identical to what the new shared atomic.h would produce have been
removed, but otherwise the changes made are just hooking up the
arch-specific files to the new infrastructure. major changes to take
advantage of the new system will come in subsequent commits.
|
