From: notaz Date: Wed, 1 Jan 2014 21:28:42 +0000 (+0200) Subject: flag/cond handling improvements X-Git-Url: https://notaz.gp2x.de/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=04f8a628893df2de90a4ba91ce3ea09ab1aa56ae;p=ia32rtools.git flag/cond handling improvements --- diff --git a/tools/translate.c b/tools/translate.c index 7248839..cd535d8 100644 --- a/tools/translate.c +++ b/tools/translate.c @@ -1937,22 +1937,36 @@ static int scan_for_mod_opr0(struct parsed_op *po_test, return -1; } -static int scan_for_flag_set(int i, int *branched, int *setters, - int *setter_cnt) +static int scan_for_flag_set(int i, int magic, int *branched, + int *setters, int *setter_cnt) { + struct label_ref *lr; int ret; while (i >= 0) { + if (ops[i].cc_scratch == magic) { + ferr(&ops[i], "%s looped\n", __func__); + return -1; + } + ops[i].cc_scratch = magic; + if (g_labels[i][0] != 0) { *branched = 1; - if (g_label_refs[i].next != NULL) - return -1; + + lr = &g_label_refs[i]; + for (; lr->next; lr = lr->next) { + ret = scan_for_flag_set(lr->i, magic, + branched, setters, setter_cnt); + if (ret < 0) + return ret; + } + if (i > 0 && LAST_OP(i - 1)) { i = g_label_refs[i].i; continue; } - ret = scan_for_flag_set(g_label_refs[i].i, branched, - setters, setter_cnt); + ret = scan_for_flag_set(lr->i, magic, + branched, setters, setter_cnt); if (ret < 0) return ret; } @@ -2162,6 +2176,21 @@ static void add_label_ref(struct label_ref *lr, int op_i) lr->next = lr_new; } +static void output_std_flags(FILE *fout, struct parsed_op *po, + int *pfomask, const char *dst_opr_text) +{ + if (*pfomask & (1 << PFO_Z)) { + fprintf(fout, "\n cond_z = (%s%s == 0);", + lmod_cast_u(po, po->operand[0].lmod), dst_opr_text); + *pfomask &= ~(1 << PFO_Z); + } + if (*pfomask & (1 << PFO_S)) { + fprintf(fout, "\n cond_s = (%s%s < 0);", + lmod_cast_s(po, po->operand[0].lmod), dst_opr_text); + *pfomask &= ~(1 << PFO_S); + } +} + static void gen_func(FILE *fout, FILE *fhdr, const char *funcn, int opcnt) { struct parsed_op *po, *delayed_flag_op = NULL, *tmp_op; @@ -2547,7 +2576,8 @@ tailcall: { int setters[16], cnt = 0, branched = 0; - ret = scan_for_flag_set(i, &branched, setters, &cnt); + ret = scan_for_flag_set(i, i + opcnt * 6, + &branched, setters, &cnt); if (ret < 0 || cnt <= 0) ferr(po, "unable to trace flag setter(s)\n"); if (cnt > ARRAY_SIZE(setters)) @@ -2570,16 +2600,19 @@ tailcall: pfomask = 1 << PFO_Z; } else { - if ((pfo != PFO_Z && pfo != PFO_S && pfo != PFO_P) + // see if we'll be able to handle based on op result + if ((tmp_op->op != OP_AND && tmp_op->op != OP_OR + && pfo != PFO_Z && pfo != PFO_S && pfo != PFO_P) + || branched || scan_for_mod_opr0(tmp_op, setters[j] + 1, i) >= 0) pfomask = 1 << pfo; } if (pfomask) { tmp_op->pfomask |= pfomask; cmp_result_vars |= pfomask; - // note: may overwrite, currently not a problem - po->datap = tmp_op; } + // note: may overwrite, currently not a problem + po->datap = tmp_op; } if (po->op == OP_ADC || po->op == OP_SBB) @@ -2742,6 +2775,7 @@ tailcall: int is_inv = 0; pfo = split_cond(po, po->op, &is_inv); + tmp_op = po->datap; // we go through all this trouble to avoid using parsed_flag_op, // which makes generated code much nicer @@ -2751,17 +2785,18 @@ tailcall: is_delayed = 1; } else if (last_arith_dst != NULL - && (pfo == PFO_Z || pfo == PFO_S || pfo == PFO_P)) + && (pfo == PFO_Z || pfo == PFO_S || pfo == PFO_P + || (tmp_op && (tmp_op->op == OP_AND || tmp_op->op == OP_OR)) + )) { out_src_opr_u32(buf3, sizeof(buf3), po, last_arith_dst); out_test_for_cc(buf1, sizeof(buf1), po, pfo, is_inv, last_arith_dst->lmod, buf3); is_delayed = 1; } - else if (po->datap != NULL) { + else if (tmp_op != NULL) { // use preprocessed flag calc results - tmp_op = po->datap; - if (!tmp_op || !(tmp_op->pfomask & (1 << pfo))) + if (!(tmp_op->pfomask & (1 << pfo))) ferr(po, "not prepared for pfo %d\n", pfo); // note: is_inv was not yet applied @@ -2924,22 +2959,44 @@ tailcall: case OP_OR: propagate_lmod(po, &po->operand[0], &po->operand[1]); // fallthrough - case OP_SHL: - case OP_SHR: dualop_arith: assert_operand_cnt(2); fprintf(fout, " %s %s= %s;", out_dst_opr(buf1, sizeof(buf1), po, &po->operand[0]), op_to_c(po), out_src_opr_u32(buf2, sizeof(buf2), po, &po->operand[1])); - if (pfomask & (1 << PFO_Z)) { - fprintf(fout, "\n cond_z = (%s == 0);", buf1); - pfomask &= ~(1 << PFO_Z); - } - if (pfomask & (1 << PFO_S)) { - fprintf(fout, "\n cond_s = ((s32)%s < 0);", buf1); - pfomask &= ~(1 << PFO_S); + output_std_flags(fout, po, &pfomask, buf1); + last_arith_dst = &po->operand[0]; + delayed_flag_op = NULL; + break; + + case OP_SHL: + case OP_SHR: + assert_operand_cnt(2); + out_dst_opr(buf1, sizeof(buf1), po, &po->operand[0]); + if (pfomask & (1 << PFO_C)) { + if (po->operand[1].type == OPT_CONST) { + l = lmod_bytes(po, po->operand[0].lmod) * 8; + j = po->operand[1].val; + j %= l; + if (j != 0) { + if (po->op == OP_SHL) + j = l - j; + else + j -= 1; + fprintf(fout, " cond_c = (%s & 0x%02x) ? 1 : 0;\n", + buf1, 1 << j); + } + else + ferr(po, "zero shift?\n"); + } + else + ferr(po, "TODO\n"); + pfomask &= ~(1 << PFO_C); } + fprintf(fout, " %s %s= %s;", buf1, op_to_c(po), + out_src_opr_u32(buf2, sizeof(buf2), po, &po->operand[1])); + output_std_flags(fout, po, &pfomask, buf1); last_arith_dst = &po->operand[0]; delayed_flag_op = NULL; break; @@ -2950,6 +3007,7 @@ tailcall: fprintf(fout, " %s = %s%s >> %s;", buf1, lmod_cast_s(po, po->operand[0].lmod), buf1, out_src_opr_u32(buf2, sizeof(buf2), po, &po->operand[1])); + output_std_flags(fout, po, &pfomask, buf1); last_arith_dst = &po->operand[0]; delayed_flag_op = NULL; break; @@ -2969,6 +3027,7 @@ tailcall: } else ferr(po, "TODO\n"); + output_std_flags(fout, po, &pfomask, buf1); last_arith_dst = &po->operand[0]; delayed_flag_op = NULL; break;