i386: Micro-optimize ix86_expand_sse_extend
Partial vector src is forced to a register as ops[1], we can use it
instead of SRC in the call to ix86_expand_sse_cmp. This change avoids
forcing operand[1] to a register in sign/zero-extend expanders.
gcc/ChangeLog:
* config/i386/i386-expand.cc (ix86_expand_sse_extend): Use ops[1]
instead of src in the call to ix86_expand_sse_cmp.
* config/i386/sse.md (<any_extend:insn>v8qiv8hi2): Do not
force operands[1] to a register.
(<any_extend:insn>v4hiv4si2): Ditto.
(<any_extend:insn>v2siv2di2): Ditto.