qemu /
qemu /
5b80dcf95b9a196c15c12b0226f93732c1b1a843 target/i386/emulate: mostly rewrite flags handling
While Bochs's algorithms are pretty solid, there are small opportunities
to improve them or to make their logic more similar to TCG's handling
of condition codes.
- use a single bit for the difference between bits 0..7 of result and PF.
This is useful because "set only ZF" is not a common case.
- place SD in the same place as SF
- move CF and PO at bits 62 and 63 when target_ulong is 64-bits wide,
so that 64-bit ALU operations need fewer shifts
- use rotates to move CF and AF from auxbits to their eflags position
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
3 files changed
