As Segher suggested, this patch is to emit the error message if the split condition of define_insn_and_split is empty while the insn condition isn't.
gcc/ChangeLog: * gensupport.c (process_rtx): Emit error message for empty split condition in define_insn_and_split while the insn condition isn't. --- gcc/gensupport.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/gcc/gensupport.c b/gcc/gensupport.c index 0f19bd70664..52cee120215 100644 --- a/gcc/gensupport.c +++ b/gcc/gensupport.c @@ -620,6 +620,9 @@ process_rtx (rtx desc, file_location loc) } else if (GET_CODE (desc) == DEFINE_INSN_AND_REWRITE) error_at (loc, "the rewrite condition must start with `&&'"); + else if (split_cond[0] == '\0' && strlen (XSTR (desc, 2)) != 0) + error_at (loc, "the split condition mustn't be empty if the " + "insn condition isn't empty"); XSTR (split, 1) = split_cond; if (GET_CODE (desc) == DEFINE_INSN_AND_REWRITE) XVEC (split, 2) = gen_rewrite_sequence (XVEC (desc, 1)); -- 2.17.1