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How to generate jump_table_data in rtl optimizers


Hi,
I used below code snippet to generate jump_table_data:

//setup label refs
start_sequence ();
emit_jump_table_data(gen_rtx_
ADDR_DIFF_VEC (CASE_VECTOR_MODE,

            base_label_ref,

            label_refs...))
insns = get_insns ();
end_sequence ();
split_edge_and_insert (edge, insns);

But later on GCC exited with below error message:

xxx.c:15:1: error: unrecognizable insn:
 }
 ^
(insn 187 109 113 3 (jump_table_data 185 0 0 (addr_diff_vec:DI
(label_ref:DI 184)
             [
                (label_ref:DI 178)
                (label_ref:DI 179)
                (label_ref:DI 180)
                (label_ref:DI 181)
                (label_ref:DI 182)
                (label_ref:DI 183)
                (label_ref:DI 184)
            ]
            (const_int 0 [0])
            (const_int 0 [0]))) -1
     (nil))
xxx.c:15:1: internal compiler error: in extract_insn, at recog.c:2286

Seems what GCC expecting is as below:

(jump_table_data 185 0 0 (addr_diff_vec:DI (label_ref:DI 184)
             [
                (label_ref:DI 178)
                (label_ref:DI 179)
                (label_ref:DI 180)
                (label_ref:DI 181)
                (label_ref:DI 182)
                (label_ref:DI 183)
                (label_ref:DI 184)
            ]
            (const_int 0 [0])
            (const_int 0 [0])))

The outer insn structure is created in emit_insn_after and make_insn_raw.

I looked into stmt.c:emit_case_dispatch_table, seems GCC used
record_insns there, and it only inserts insn to list, and does not
create the outer insn structure.

Since record_insns/record_insns_nobb are deprecated according to
comments, my question is how to generate jump_table_data then?  Is
jump_table_data not supported in emit_insn_*?

Thanks,
bin


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