Hi! On the gcc.dg/vect/pr88598-3.c testcase, gen_vec_extract... is called with operands[1] that is already a subreg - (subreg:V4SF (reg:V4SI 201 [ _31 ]) 0) and wraps it in another SUBREG, which is invalid in RTL.
In all the following 4 spots I've verified that the operand's mode is some 128-bit vector mode and the mode we want to use is another 128-bit vector mode, so we are just VCEing the operand to another same sized mode, so we can call gen_lowpart to handle everything for us (there are no worries about big vs. little endian etc.). Paul Hua has kindly bootstrapped/regtested this on mips (mentioned in the PR), ok for trunk? 2019-03-14 Jakub Jelinek <ja...@redhat.com> PR target/89378 * config/mips/mips.c (mips_expand_vec_cond_expr): Use gen_lowpart instead of gen_rtx_SUBREG. * config/mips/mips-msa.md (vec_extract<mode><unitmode>): Likewise. --- gcc/config/mips/mips.c.jj 2019-03-11 22:57:00.113599336 +0100 +++ gcc/config/mips/mips.c 2019-03-13 15:46:53.597014213 +0100 @@ -22265,7 +22265,7 @@ mips_expand_vec_cond_expr (machine_mode if (mode != vimode) { xop1 = gen_reg_rtx (vimode); - emit_move_insn (xop1, gen_rtx_SUBREG (vimode, operands[1], 0)); + emit_move_insn (xop1, gen_lowpart (vimode, operands[1])); } emit_move_insn (src1, xop1); } @@ -22282,7 +22282,7 @@ mips_expand_vec_cond_expr (machine_mode if (mode != vimode) { xop2 = gen_reg_rtx (vimode); - emit_move_insn (xop2, gen_rtx_SUBREG (vimode, operands[2], 0)); + emit_move_insn (xop2, gen_lowpart (vimode, operands[2])); } emit_move_insn (src2, xop2); } --- gcc/config/mips/mips-msa.md.jj 2019-01-01 12:37:22.657884713 +0100 +++ gcc/config/mips/mips-msa.md 2019-03-13 15:45:01.442789417 +0100 @@ -346,12 +346,12 @@ (define_expand "vec_extract<mode><unitmo operands[2] accordingly. */ rtx wd = gen_reg_rtx (V16QImode); rtx ws = gen_reg_rtx (V16QImode); - emit_move_insn (ws, gen_rtx_SUBREG (V16QImode, operands[1], 0)); + emit_move_insn (ws, gen_lowpart (V16QImode, operands[1])); rtx n = GEN_INT (val * GET_MODE_SIZE (<UNITMODE>mode)); gcc_assert (INTVAL (n) < GET_MODE_NUNITS (V16QImode)); emit_insn (gen_msa_sldi_b (wd, ws, ws, n)); temp = gen_reg_rtx (<MODE>mode); - emit_move_insn (temp, gen_rtx_SUBREG (<MODE>mode, wd, 0)); + emit_move_insn (temp, gen_lowpart (<MODE>mode, wd)); } emit_insn (gen_msa_vec_extract_<msafmt_f> (operands[0], temp)); DONE; Jakub