This is supported on x86-64 and target feature
sse4a
only.Expand description
Extracts the bit range specified by y
from the lower 64 bits of x
.
The [13:8]
bits of y
specify the index of the bit-range to extract. The
[5:0]
bits of y
specify the length of the bit-range to extract. All
other bits are ignored.
If the length is zero, it is interpreted as 64
. If the length and index
are zero, the lower 64 bits of x
are extracted.
If length == 0 && index > 0
or length + index > 64
the result is
undefined.