Commit da1d7759 authored by Sebastian Macke's avatar Sebastian Macke Committed by Jia Liu
Browse files

target-openrisc: Remove unnecessary code generated by jump instructions 



The sr_f variable is only used for the l.bf and l.bnf instructions.
For clarity the code is also rewritten using a switch statement instead
of if chaining.

Signed-off-by: default avatarSebastian Macke <sebastian@macke.de>
Reviewed-by: default avatarJia Liu <proljc@gmail.com>
Signed-off-by: default avatarJia Liu <proljc@gmail.com>
parent 352367e8

target-openrisc/translate.c

+26 −19
Original line number Diff line number Diff line
@@ -209,42 +209,49 @@ static void gen_goto_tb(DisasContext *dc, int n, target_ulong dest) 
static void gen_jump(DisasContext *dc, uint32_t imm, uint32_t reg, uint32_t op0)

{

    target_ulong tmp_pc;

    int lab = gen_new_label();

    TCGv sr_f = tcg_temp_new();

    /* N26, 26bits imm */

    tmp_pc = sign_extend((imm<<2), 26) + dc->pc;

    tcg_gen_andi_tl(sr_f, cpu_sr, SR_F);



    if (op0 == 0x00) {    /* l.j */

    switch (op0) {

    case 0x00:     /* l.j */

        tcg_gen_movi_tl(jmp_pc, tmp_pc);

    } else if (op0 == 0x01) {    /* l.jal */

        break;

    case 0x01:     /* l.jal */

        tcg_gen_movi_tl(cpu_R[9], (dc->pc + 8));

        tcg_gen_movi_tl(jmp_pc, tmp_pc);

    } else if (op0 == 0x03) {    /* l.bnf */

        tcg_gen_movi_tl(jmp_pc, dc->pc+8);

        tcg_gen_brcondi_i32(TCG_COND_EQ, sr_f, SR_F, lab);

        tcg_gen_movi_tl(jmp_pc, tmp_pc);

        gen_set_label(lab);

    } else if (op0 == 0x04) {    /* l.bf */

        break;

    case 0x03:     /* l.bnf */

    case 0x04:     /* l.bf  */

        {

            int lab = gen_new_label();

            TCGv sr_f = tcg_temp_new();

            tcg_gen_movi_tl(jmp_pc, dc->pc+8);

        tcg_gen_brcondi_i32(TCG_COND_NE, sr_f, SR_F, lab);

            tcg_gen_andi_tl(sr_f, cpu_sr, SR_F);

            tcg_gen_brcondi_i32(op0 == 0x03 ? TCG_COND_EQ : TCG_COND_NE,

                                sr_f, SR_F, lab);

            tcg_gen_movi_tl(jmp_pc, tmp_pc);

            gen_set_label(lab);

    } else if (op0 == 0x11) {    /* l.jr */

            tcg_temp_free(sr_f);

        }

        break;

    case 0x11:     /* l.jr */

        tcg_gen_mov_tl(jmp_pc, cpu_R[reg]);

    } else if (op0 == 0x12) {    /* l.jalr */

        break;

    case 0x12:     /* l.jalr */

        tcg_gen_movi_tl(cpu_R[9], (dc->pc + 8));

        tcg_gen_mov_tl(jmp_pc, cpu_R[reg]);

    } else {

        break;

    default:

        gen_illegal_exception(dc);

        break;

    }



    tcg_temp_free(sr_f);

    dc->delayed_branch = 2;

    dc->tb_flags |= D_FLAG;

    gen_sync_flags(dc);

}





static void dec_calc(DisasContext *dc, uint32_t insn)

{

    uint32_t op0, op1, op2;