re PR target/80246 (Builtin's for POWER's dxex[q] and diex[q] use the wrong types)

gcc/
	PR target/80246
	* config/rs6000/dfp.md (dfp_dxex_<mode>): Update mode of operand 0.
	(dfp_diex_<mode>): Update mode of operand 1.
	* doc/extend.texi (dxex, dxexq): Document change to return type.
	(diex, diexq): Document change to argument type.

gcc/testsuite/
	PR target/80246
	* gcc.target/powerpc/dfp-builtin-1.c: Remove unneeded dg-skip-if for
	Darwin and SPE.
	(dxex, dxexq): Update return type.
	(diex, diexq): Update argument type.
	* gcc.target/powerpc/pr80246.c: New test.

From-SVN: r246594