https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112276
--- Comment #7 from CVS Commits <cvs-commit at gcc dot gnu.org> --- The master branch has been updated by hongtao Liu <liuho...@gcc.gnu.org>: https://gcc.gnu.org/g:f5d33d0c790a00cb5240a966dd99df9961bf57a0 commit r14-5025-gf5d33d0c790a00cb5240a966dd99df9961bf57a0 Author: liuhongt <hongtao....@intel.com> Date: Mon Oct 30 14:05:25 2023 +0800 Fix wrong code due to incorrect define_split -(define_split - [(set (match_operand:V2HI 0 "register_operand") - (eq:V2HI - (eq:V2HI - (us_minus:V2HI - (match_operand:V2HI 1 "register_operand") - (match_operand:V2HI 2 "register_operand")) - (match_operand:V2HI 3 "const0_operand")) - (match_operand:V2HI 4 "const0_operand")))] - "TARGET_SSE4_1" - [(set (match_dup 0) - (umin:V2HI (match_dup 1) (match_dup 2))) - (set (match_dup 0) - (eq:V2HI (match_dup 0) (match_dup 2)))]) the splitter is wrong when op1 == op2.(the original pattern returns 0, after split, it returns 1) So remove the splitter. Also extend another define_split to define_insn_and_split to handle below pattern 494(set (reg:V4QI 112) 495 (unspec:V4QI [ 496 (subreg:V4QI (reg:V2HF 111 [ bf ]) 0) 497 (subreg:V4QI (reg:V2HF 110 [ af ]) 0) 498 (subreg:V4QI (eq:V2HI (eq:V2HI (reg:V2HI 105) 499 (const_vector:V2HI [ 500 (const_int 0 [0]) repeated x2 501 ])) 502 (const_vector:V2HI [ 503 (const_int 0 [0]) repeated x2 504 ])) 0) 505 ] UNSPEC_BLENDV)) define_split doesn't work since pass_combine assume it produces at most 2 insns after split, but here it produces 3 since we need to move const0_rtx (V2HImode) to reg. The move insn can be eliminated later. gcc/ChangeLog: PR target/112276 * config/i386/mmx.md (*mmx_pblendvb_v8qi_1): Change define_split to define_insn_and_split to handle immediate_operand for comparison. (*mmx_pblendvb_v8qi_2): Ditto. (*mmx_pblendvb_<mode>_1): Ditto. (*mmx_pblendvb_v4qi_2): Ditto. (<code><mode>3): Remove define_split after it. (<code>v8qi3): Ditto. (<code><mode>3): Ditto. (<ode>v2hi3): Ditto. gcc/testsuite/ChangeLog: * g++.target/i386/part-vect-vcondhf.C: Adjust testcase. * gcc.target/i386/pr112276.c: New test.
