/* iffy ops that operate on a known value register can turn into goto
* or be dropped. */
static void optimize_iffy(MVMThreadContext *tc, MVMSpeshGraph *g, MVMSpeshIns *ins, MVMSpeshBB *bb) {
MVMSpeshFacts *flag_facts = MVM_spesh_get_facts(tc, g, ins->operands[0]);
MVMuint8 negated_op;
MVMuint8 truthvalue;
switch (ins->info->opcode) {
case MVM_OP_if_i:
case MVM_OP_if_s:
case MVM_OP_if_n:
case MVM_OP_if_o:
case MVM_OP_ifnonnull:
negated_op = 0;
break;
case MVM_OP_unless_i:
case MVM_OP_unless_s:
case MVM_OP_unless_n:
case MVM_OP_unless_o:
negated_op = 1;
break;
default:
return;
}
if (flag_facts->flags & MVM_SPESH_FACT_KNOWN_VALUE) {
switch (ins->info->opcode) {
case MVM_OP_if_i:
case MVM_OP_unless_i:
truthvalue = flag_facts->value.i64;
break;
case MVM_OP_if_o:
case MVM_OP_unless_o: {
MVMObject *objval = flag_facts->value.o;
MVMBoolificationSpec *bs = objval->st->boolification_spec;
MVMRegister resultreg;
switch (bs == NULL ? MVM_BOOL_MODE_NOT_TYPE_OBJECT : bs->mode) {
case MVM_BOOL_MODE_UNBOX_INT:
case MVM_BOOL_MODE_UNBOX_NUM:
case MVM_BOOL_MODE_UNBOX_STR_NOT_EMPTY:
case MVM_BOOL_MODE_UNBOX_STR_NOT_EMPTY_OR_ZERO:
case MVM_BOOL_MODE_BIGINT:
case MVM_BOOL_MODE_ITER:
case MVM_BOOL_MODE_HAS_ELEMS:
case MVM_BOOL_MODE_NOT_TYPE_OBJECT:
MVM_coerce_istrue(tc, objval, &resultreg, NULL, NULL, 0);
truthvalue = resultreg.i64;
break;
case MVM_BOOL_MODE_CALL_METHOD:
default:
return;
}
break;
}
case MVM_OP_if_n:
case MVM_OP_unless_n:
truthvalue = flag_facts->value.n64 != 0.0;
break;
default:
return;
}
} else {
return;
}
flag_facts->usages--;
if (truthvalue != negated_op) {
/* this conditional can be turned into an unconditional jump */
ins->info = MVM_op_get_op(MVM_OP_goto);
ins->operands[0] = ins->operands[1];
/* since we have an unconditional jump now, we can remove the successor
* that's in the linear_next */
MVM_spesh_manipulate_remove_successor(tc, bb, bb->linear_next);
} else {
/* this conditional can be dropped completely */
MVM_spesh_manipulate_remove_successor(tc, bb, ins->operands[1].ins_bb);
MVM_spesh_manipulate_delete_ins(tc, g, bb, ins);
}
}
/* Re-writes argument passing and parameter taking instructions to simple
* register set operations. */
static void rewrite_args(MVMThreadContext *tc, MVMSpeshGraph *inliner,
MVMSpeshGraph *inlinee, MVMSpeshBB *invoke_bb,
MVMSpeshCallInfo *call_info) {
/* Look for param-taking instructions. Track what arg instructions we
* use in the process. */
MVMSpeshBB *bb = inlinee->entry;
while (bb) {
MVMSpeshIns *ins = bb->first_ins;
while (ins) {
MVMuint16 opcode = ins->info->opcode;
MVMSpeshIns *next = ins->next;
switch (opcode) {
case MVM_OP_sp_getarg_o:
case MVM_OP_sp_getarg_i:
case MVM_OP_sp_getarg_n:
case MVM_OP_sp_getarg_s: {
MVMuint16 idx = ins->operands[1].lit_i16;
MVMSpeshIns *arg_ins = call_info->arg_ins[idx];
switch (arg_ins->info->opcode) {
case MVM_OP_arg_i:
case MVM_OP_arg_n:
case MVM_OP_arg_s:
case MVM_OP_arg_o:
/* Arg passer just becomes a set instruction; delete the
* parameter-taking instruction. */
arg_ins->info = MVM_op_get_op(MVM_OP_set);
arg_ins->operands[0] = ins->operands[0];
MVM_spesh_manipulate_delete_ins(tc, inliner, bb, ins);
MVM_spesh_get_facts(tc, inliner, arg_ins->operands[0])->usages++;
break;
case MVM_OP_argconst_i:
arg_ins->info = MVM_op_get_op(MVM_OP_const_i64);
arg_ins->operands[0] = ins->operands[0];
MVM_spesh_manipulate_delete_ins(tc, inliner, bb, ins);
MVM_spesh_get_facts(tc, inliner, arg_ins->operands[0])->usages++;
break;
case MVM_OP_argconst_n:
arg_ins->info = MVM_op_get_op(MVM_OP_const_n64);
arg_ins->operands[0] = ins->operands[0];
MVM_spesh_manipulate_delete_ins(tc, inliner, bb, ins);
MVM_spesh_get_facts(tc, inliner, arg_ins->operands[0])->usages++;
break;
case MVM_OP_argconst_s:
arg_ins->info = MVM_op_get_op(MVM_OP_const_s);
arg_ins->operands[0] = ins->operands[0];
MVM_spesh_manipulate_delete_ins(tc, inliner, bb, ins);
MVM_spesh_get_facts(tc, inliner, arg_ins->operands[0])->usages++;
break;
default:
MVM_oops(tc,
"Spesh inline: unhandled arg instruction %d",
arg_ins->info->opcode);
}
break;
}
}
ins = next;
}
bb = bb->linear_next;
}
/* Delete the prepargs instruction. */
MVM_spesh_manipulate_delete_ins(tc, inliner, invoke_bb, call_info->prepargs_ins);
}
