find_first_bit has started to be used heavily in TCG code. The current
implementation based on find_next_bit is not optimal and can't be
optimized be the compiler if the bit array has a fixed size, which is
the case most of the time.
This new implementation does not use find_next_bit and is yet small
enough to be inlined.
Cc: Corentin Chary <corentin.chary@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Move index and size fields from int to long. We need that for
migration. long is 64 bits on sane architectures, and 32bits should
be enough on all the 32bits architectures.
Signed-off-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Orit Wasserman <owasserm@redhat.com>
A common operation in instruction decoding is to take a field
from an instruction that represents a signed integer in some
arbitrary number of bits, and sign extend it into a C signed
integer type for manipulation. Provide new functions sextract32()
and sextract64() which perform this operation; they are like
the existing extract32() and extract64() except that the field
is sign-extended into the returned result.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Message-id: 1372419632-5521-2-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
We had two copies of a ffs function for longs with subtly different
semantics and, for the one in bitops.h, a confusing name: the result
was off-by-one compared to the library function ffsl.
Unify the functions into one, and solve the name problem by calling
the 0-based functions "bitops_ctzl" and "bitops_ctol" respectively.
This also fixes the build on platforms with ffsl, including Mac OS X
and Windows.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Andreas Färber <afaerber@suse.de>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
