i386: Always enable mov<V_32:mode> patterns [PR103894]

i386: Always enable mov<V_32:mode> patterns [PR103894]

Middle end tries to generate V4QImode moves to implement V2QImode inserts
and calls emit_move_multi_word when V4QImode moves are unavailable, as is
the case with 32-bit vector moves, constrainted with TARGET_SSE2.

However, this triggers

  gcc_assert (mode_size >= UNITS_PER_WORD);

in emit_move_multi_word, since mode_size of V4QImode operand is less than
UNITS_PER_WORD of 64-bit targets.

The patch unconditionally enables 32-bit vector moves to match 16-bit
vector moves.  This also enables implementation of 32-bit vector logic
operations with GPR in a follow-up patch.

2022-01-03  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:

	PR target/103894
	* config/i386/mmx.md (mov<V_32:mode>): Remove TARGET_SSE2 constraint.
	(mov<V_32:mode>_internal): Ditto.
	(*push<V_32:mode>_rex64): Ditto.
	(movmisalign<V_32:mode>): Ditto.
	(*push<V_32:mode>_rex64 splitter): Enable for
	TARGET_64BIT && TARGET_SSE.
	(*push<V_32:mode>2): Remove insn pattern.

gcc/testsuite/ChangeLog:

	PR target/103894
	* gcc.target/i386/pr103894.c: New test.