x86: Get the widest vector mode from MOVE_MAX

x86: Get the widest vector mode from MOVE_MAX

Since MOVE_MAX defines the maximum number of bytes that an instruction
can move quickly between memory and registers, use it to get the widest
vector mode in vector loop when inlining memcpy and memset.

gcc/

	PR target/120708
	* config/i386/i386-expand.cc (ix86_expand_set_or_cpymem): Use
	MOVE_MAX to get the widest vector mode in vector loop.

gcc/testsuite/

	PR target/120708
	* gcc.target/i386/memcpy-pr120708-1.c: New test.
	* gcc.target/i386/memcpy-pr120708-2.c: Likewise.
	* gcc.target/i386/memcpy-pr120708-3.c: Likewise.
	* gcc.target/i386/memcpy-pr120708-4.c: Likewise.
	* gcc.target/i386/memcpy-pr120708-5.c: Likewise.
	* gcc.target/i386/memcpy-pr120708-6.c: Likewise.
	* gcc.target/i386/memset-pr120708-1.c: Likewise.
	* gcc.target/i386/memset-pr120708-2.c: Likewise.
	* gcc.target/i386/memcpy-strategy-1.c: Drop dg-skip-if.  Replace
	-march=atom with -mno-avx -msse2 -mtune=generic
	-mtune-ctrl=^sse_typeless_stores.
	* gcc.target/i386/memcpy-strategy-2.c: Likewise.
	* gcc.target/i386/memcpy-vector_loop-1.c: Likewise.
	* gcc.target/i386/memcpy-vector_loop-2.c: Likewise.
	* gcc.target/i386/memset-vector_loop-1.c: Likewise.
	* gcc.target/i386/memset-vector_loop-2.c: Likewise.

Signed-off-by: H.J. Lu <hjl.tools@gmail.com>