Re: [Qemu-devel] [PATCH 0/2] Provide sextract32() and sextract64()

[Peter Maydell]

Ping!

thanks
-- PMM

On 28 June 2013 12:40, Peter Maydell <address@hidden> wrote:
> 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.
>
> I agree with Markus that sign-extending versions of our
> extract functions are more flexible than the simple sext()
> I proposed in an earlier RFC, hence the switch in this patch.
> The other change is patch 2, which provides some simple test
> cases. (Will be handy if we ever decide to revamp to avoid
> the dependency on shift-left-signed behaviour.)
>
> Peter Maydell (2):
>   bitops: Provide sextract32() and sextract64()
>   tests: Add test-bitops.c with some sextract tests
>
>  include/qemu/bitops.h |   50 +++++++++++++++++++++++++++++++++
>  tests/Makefile        |    2 ++
>  tests/test-bitops.c   |   75 
> +++++++++++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 127 insertions(+)
>  create mode 100644 tests/test-bitops.c
>