[AArch64][SVE] Asm: Support for UDOT/SDOT instructions.
The signed/unsigned DOT instructions perform a dot-product on
quadtuplets from two source vectors and accumulate the result in
the destination register. The instructions come in two forms:
Vector form, e.g.
sdot z0.s, z1.b, z2.b - signed dot product on four 8-bit quad-tuplets,
accumulating results in 32-bit elements.
udot z0.d, z1.h, z2.h - unsigned dot product on four 16-bit quad-tuplets,
accumulating results in 64-bit elements.
Indexed form, e.g.
sdot z0.s, z1.b, z2.b[3] - signed dot product on four 8-bit quad-tuplets
with specified quadtuplet from second
source vector, accumulating results in 32-bit
elements.
udot z0.d, z1.h, z2.h[1] - dot product on four 16-bit quad-tuplets
with specified quadtuplet from second
source vector, accumulating results in 64-bit
elements.
llvm-svn: 337372