Summary: disable vectorization of a memory access with more elements per vector than one which is used for alignment on sparc
Reviewed-by: twisti

Summary: Increase vector size up to 256-bits for YMM AVX registers on x86.
Reviewed-by: never, twisti, roland

Summary: Replace call_epilog() encoding with macroassembler use. Moved duplicated code to x86.ad. Fixed return_addr() definition.
Reviewed-by: never

Summary: Use 3-operands SIMD instructions in C2 generated code for machines with AVX.
Reviewed-by: never