- Rename X86_SSE_CC_NE to X86_SSE_CC_NEQ (match Intel reference manual)
- Rename MOVDLX to MOVDXD (%Xmm register as Destination)
- Rename MOVDQX to MOVQXD (%Xmm register as Destination)
- Rename MOVDXL to MOVDXS (%Xmm register as Source)
- Rename MOVDXQ to MOVQXS (%Xmm register as Source)
explicitly generated from mig. The advantage of that is to provide a "fast"
path for x86_64 on Leopard too (fault address in code[1]).
By "fast", this means +33% faster wrt. explicitly thread_get_state() but
still pretty slow (40 usec/fault). This is on par with the i386 code path though.
Leopard kernel faster? This is pure marketing hype. For 32-bit applications,
Mach exception recovery is 60% slower. For 64-bit applications, this is up
to 40% faster though. In any case, MacOS X remains pretty slow wrt. Linux...
environment variable: SIGSEGV_MACH_FAULT. It can be set to "direct" to
assume the fault address comes from code[1] argument, or "slow" to use
the slow path through thread_get_status(EXCEPTION_STATE)->faultvaddr.
in the bundle. This is faster and more accurate as this avoids emulation.
Also clean-up code so that to prepare the use of lib uaccess on hpux/ia64.
XXX: this will need explicit use of uint64_t to define registers because
HP/UX is ILP32 capable and all registers are 64-bit capable so "unsigned long"
won't fit.
complex than expected but it was fun to play with. Who designed this ISA?
I'd love to see how the decoder is implemented in HW, by all means it is
not "simplified" unless I missed some pattern...
XNU 792.21.3 (10.4.10) and XNU 1228 (10.5.0), exception handler code[1] always
contains the fault address nowadays. So make it the default fast path but keep
provisions to check that at run-time first.
This yields a nearly 4x improvement in SIGSEGV recovery but MacOS X is still
suboptimal wrt. Linux, so VOSF is still not possible with frameskip == 0.
XXX: the ppc kernel had bugs that caused DAR (put into code[1]) to be incorrectly
decoded. This would need a broader test audience or more careful audit of the
sources changes.
