Looks like my idea of what a "borrow" is was wrong. The PoP says:
"If the resulting subtraction results in a carry out of bit zero, a value
of one is placed in the corresponding element of the first operand;
otherwise, a value of zero is placed in the corresponding element"
As clarified by Richard, all we have to do is invert the result.
Fixes: 1ee2d7ba72 ("s390x/tcg: Implement VECTOR SUBTRACT COMPUTE BORROW INDICATION")
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20191021085715.3797-5-david@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
We forgot to propagate the highest bit accross the high doubleword in
two cases (shift >=64).
Fixes: 5f724887e3 ("s390x/tcg: Implement VECTOR SHIFT RIGHT ARITHMETIC")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20191021085715.3797-4-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
We missed that we always read a "double-wide even-odd element
pair of the fourth operand". Fix it in all four variants.
Fixes: 1b430aec41 ("s390x/tcg: Implement VECTOR MULTIPLY AND ADD *")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20191021085715.3797-3-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
We have to read from odd offsets.
Fixes: 2bf3ee38f1 ("s390x/tcg: Implement VECTOR MULTIPLY *")
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20191021085715.3797-2-david@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Let's return the cc value directly via cpu_env. Unfortunately there
isn't a simple way to calculate the value lazily - one would have to
calculate and store e.g. the population count of the mask and the
result so it can be evaluated in a cc helper.
But as VTM only sets the cc, we can assume the value will be needed soon
either way.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Let's keep it simple for now and handle 8/16 bit elements via helpers.
Especially for 8/16, we could come up with some bit tricks.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Similar to VECTOR SHIFT RIGHT ARITHMETICAL.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Similar to VECTOR SHIFT LEFT ARITHMETIC. Add s390_vec_sar() similar to
s390_vec_shr().
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
We can reuse the existing 128-bit shift utility function.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Use the new vector expansion for GVecGen3i.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Take care of properly taking the modulo of the count. We might later
want to come back and create a variant of VERLL where the base register
is 0, resulting in an immediate.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Similar to VECTOR COUNT TRAILING ZEROES.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Yet another set of variants. Implement it similar to VECTOR MULTIPLY AND
ADD *. At least for one variant we have a gvec helper we can reuse.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Quite some variants to handle. At least handle some 32-bit element
variants via gvec expansion (we could also handle 16/32-bit variants
for ODD and EVEN easily via gvec expansion, but let's keep it simple
for now).
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
A galois field multiplication in field 2 is like binary multiplication,
however instead of doing ordinary binary additions, xor's are performed.
So no carries are considered.
Implement all variants via helpers. s390_vec_sar() and s390_vec_shr()
will be reused later on.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Implement it similar to VECTOR COUNT LEADING ZEROS.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
For 8/16, use the 32 bit variant and properly subtract the added
leading zero bits.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Similar to VECTOR AVERAGE but without sign extension.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
Handle 32/64-bit elements via gvec expansion and the 8/16 bits via
ool helpers.
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Hildenbrand <david@redhat.com>
