On Sun, 2026-08-09 at 15:35 -0700, Richard Henderson wrote: > Unroll first iteration, so that always_true_p is not used, > Drop some local variables and use 'decoders' directly. > > Signed-off-by: Richard Henderson <[email protected]>
Reviewed-by: Alistair Francis <[email protected]> Alistair > --- > disas/riscv.c | 63 +++++++++++++++++++++++++------------------------ > -- > 1 file changed, 31 insertions(+), 32 deletions(-) > > diff --git a/disas/riscv.c b/disas/riscv.c > index 70ea41f125..9880b8de20 100644 > --- a/disas/riscv.c > +++ b/disas/riscv.c > @@ -5419,41 +5419,40 @@ static GString *disasm_inst(rv_isa isa, > uint64_t pc, rv_inst inst, > .inst = inst, > .cfg = cfg, > }; > - > - static const struct { > - bool (*guard_func)(const RISCVCPUConfig *); > - const rv_opcode_data *opcode_data; > - void (*decode_func)(rv_decode *, rv_isa); > - } decoders[] = { > - { always_true_p, rvi_opcode_data, decode_inst_opcode }, > - { has_xtheadba_p, xthead_opcode_data, decode_xtheadba }, > - { has_xtheadbb_p, xthead_opcode_data, decode_xtheadbb }, > - { has_xtheadbs_p, xthead_opcode_data, decode_xtheadbs }, > - { has_xtheadcmo_p, xthead_opcode_data, decode_xtheadcmo }, > - { has_xtheadcondmov_p, xthead_opcode_data, > decode_xtheadcondmov }, > - { has_xtheadfmemidx_p, xthead_opcode_data, > decode_xtheadfmemidx }, > - { has_xtheadfmv_p, xthead_opcode_data, decode_xtheadfmv }, > - { has_xtheadmac_p, xthead_opcode_data, decode_xtheadmac }, > - { has_xtheadmemidx_p, xthead_opcode_data, > decode_xtheadmemidx }, > - { has_xtheadmempair_p, xthead_opcode_data, > decode_xtheadmempair }, > - { has_xtheadsync_p, xthead_opcode_data, decode_xtheadsync }, > - { has_XVentanaCondOps_p, ventana_opcode_data, > decode_xventanacondops }, > - { has_xlrbr_p, rv_xlrbr_opcode_data, decode_xlrbr }, > - }; > - > const rv_opcode_data *op; > > - for (size_t i = 0; i < ARRAY_SIZE(decoders); i++) { > - bool (*guard_func)(const RISCVCPUConfig *) = > decoders[i].guard_func; > - const rv_opcode_data *opcode_data = decoders[i].opcode_data; > - void (*decode_func)(rv_decode *, rv_isa) = > decoders[i].decode_func; > + dec.opcode_data = rvi_opcode_data; > + decode_inst_opcode(&dec, isa); > > - /* always_true_p don't dereference cfg */ > - if (((i == 0) || cfg) && guard_func(cfg)) { > - dec.opcode_data = opcode_data; > - decode_func(&dec, isa); > - if (dec.op != rv_op_illegal) > - break; > + if (dec.op == rv_op_illegal && cfg) { > + static const struct { > + bool (*guard_func)(const RISCVCPUConfig *); > + const rv_opcode_data *opcode_data; > + void (*decode_func)(rv_decode *, rv_isa); > + } decoders[] = { > + { has_xtheadba_p, xthead_opcode_data, decode_xtheadba }, > + { has_xtheadbb_p, xthead_opcode_data, decode_xtheadbb }, > + { has_xtheadbs_p, xthead_opcode_data, decode_xtheadbs }, > + { has_xtheadcmo_p, xthead_opcode_data, decode_xtheadcmo > }, > + { has_xtheadcondmov_p, xthead_opcode_data, > decode_xtheadcondmov }, > + { has_xtheadfmemidx_p, xthead_opcode_data, > decode_xtheadfmemidx }, > + { has_xtheadfmv_p, xthead_opcode_data, decode_xtheadfmv > }, > + { has_xtheadmac_p, xthead_opcode_data, decode_xtheadmac > }, > + { has_xtheadmemidx_p, xthead_opcode_data, > decode_xtheadmemidx }, > + { has_xtheadmempair_p, xthead_opcode_data, > decode_xtheadmempair }, > + { has_xtheadsync_p, xthead_opcode_data, > decode_xtheadsync }, > + { has_XVentanaCondOps_p, ventana_opcode_data, > decode_xventanacondops }, > + { has_xlrbr_p, rv_xlrbr_opcode_data, decode_xlrbr }, > + }; > + > + for (size_t i = 0; i < ARRAY_SIZE(decoders); i++) { > + if (decoders[i].guard_func(cfg)) { > + dec.opcode_data = decoders[i].opcode_data; > + decoders[i].decode_func(&dec, isa); > + if (dec.op != rv_op_illegal) { > + break; > + } > + } > } > } >
