* config/rs6000/rs6000.opt (mmulhw): New option.
	* doc/invoke.texi (-mmulhw): Document.
	* config/rs6000/rs6000.c (rs6000_override_options): Enable -mmulhw
	for 405 and 440.
	* config/rs6000/rs6000.md: Add half-word multiply and
	multiply-accumulate instructions for 405 and 440.

testsuite:
	* gcc.target/powerpc/405-macchw-1.c,
	gcc.target/powerpc/405-macchw-2.c,
	gcc.target/powerpc/405-macchwu-1.c,
	gcc.target/powerpc/405-macchwu-2.c,
	gcc.target/powerpc/405-machhw-1.c,
	gcc.target/powerpc/405-machhw-2.c,
	gcc.target/powerpc/405-machhwu-1.c,
	gcc.target/powerpc/405-machhwu-2.c,
	gcc.target/powerpc/405-maclhw-1.c,
	gcc.target/powerpc/405-maclhw-2.c,
	gcc.target/powerpc/405-maclhwu-1.c,
	gcc.target/powerpc/405-maclhwu-2.c,
	gcc.target/powerpc/405-mulchw-1.c,
	gcc.target/powerpc/405-mulchw-2.c,
	gcc.target/powerpc/405-mulchwu-1.c,
	gcc.target/powerpc/405-mulchwu-2.c,
	gcc.target/powerpc/405-mulhhw-1.c,
	gcc.target/powerpc/405-mulhhw-2.c,
	gcc.target/powerpc/405-mulhhwu-1.c,
	gcc.target/powerpc/405-mulhhwu-2.c,
	gcc.target/powerpc/405-mullhw-1.c,
	gcc.target/powerpc/405-mullhw-2.c,
	gcc.target/powerpc/405-mullhwu-1.c,
	gcc.target/powerpc/405-mullhwu-2.c,
	gcc.target/powerpc/405-nmacchw-1.c,
	gcc.target/powerpc/405-nmacchw-2.c,
	gcc.target/powerpc/405-nmachhw-1.c,
	gcc.target/powerpc/405-nmachhw-2.c,
	gcc.target/powerpc/405-nmaclhw-1.c,
	gcc.target/powerpc/405-nmaclhw-2.c,
	gcc.target/powerpc/440-macchw-1.c,
	gcc.target/powerpc/440-macchw-2.c,
	gcc.target/powerpc/440-macchwu-1.c,
	gcc.target/powerpc/440-macchwu-2.c,
	gcc.target/powerpc/440-machhw-1.c,
	gcc.target/powerpc/440-machhw-2.c,
	gcc.target/powerpc/440-machhwu-1.c,
	gcc.target/powerpc/440-machhwu-2.c,
	gcc.target/powerpc/440-maclhw-1.c,
	gcc.target/powerpc/440-maclhw-2.c,
	gcc.target/powerpc/440-maclhwu-1.c,
	gcc.target/powerpc/440-maclhwu-2.c,
	gcc.target/powerpc/440-mulchw-1.c,
	gcc.target/powerpc/440-mulchw-2.c,
	gcc.target/powerpc/440-mulchwu-1.c,
	gcc.target/powerpc/440-mulchwu-2.c,
	gcc.target/powerpc/440-mulhhw-1.c,
	gcc.target/powerpc/440-mulhhw-2.c,
	gcc.target/powerpc/440-mulhhwu-1.c,
	gcc.target/powerpc/440-mulhhwu-2.c,
	gcc.target/powerpc/440-mullhw-1.c,
	gcc.target/powerpc/440-mullhw-2.c,
	gcc.target/powerpc/440-mullhwu-1.c,
	gcc.target/powerpc/440-mullhwu-2.c,
	gcc.target/powerpc/440-nmacchw-1.c,
	gcc.target/powerpc/440-nmacchw-2.c,
	gcc.target/powerpc/440-nmachhw-1.c,
	gcc.target/powerpc/440-nmachhw-2.c,
	gcc.target/powerpc/440-nmaclhw-1.c,
	gcc.target/powerpc/440-nmaclhw-2.c: New tests.

From-SVN: r107344