output/outdbg.c

/* SPDX-License-Identifier: BSD-2-Clause */
/* Copyright 1996-2020 The NASM Authors - All Rights Reserved */

/*
 * outdbg.c	output routines for the Netwide Assembler to produce
 *		a debugging trace
 */

#include "compiler.h"

#include "nctype.h"
#include <errno.h>

#include "nasm.h"
#include "nasmlib.h"
#include "outform.h"
#include "outlib.h"
#include "insns.h"
#include "dbginfo.h"

#ifdef OF_DBG

struct Section {
    struct Section *next;
    int32_t number;
    char *name;
} *dbgsect;

static unsigned long dbg_max_data_dump = 128;
static bool section_labels = true;
static bool subsections_via_symbols = false;
static int32_t init_seg;

const struct ofmt of_dbg;
static void dbg_init(void)
{
    dbgsect = NULL;
    fprintf(ofile, "NASM Output format debug dump\n");
    fprintf(ofile, "input file  = %s\n", inname);
    fprintf(ofile, "output file = %s\n", outname);
    init_seg = seg_alloc();
}

static void dbg_reset(void)
{
    fprintf(ofile, "*** pass reset: pass = %"PRId64" (%s)\n",
            pass_count(), pass_type_name());
}

static void dbg_cleanup(void)
{
    dfmt->cleanup();
    while (dbgsect) {
        struct Section *tmp = dbgsect;
        dbgsect = dbgsect->next;
        nasm_free(tmp->name);
        nasm_free(tmp);
    }
}

static int32_t dbg_add_section(char *name, int *bits, const char *whatwecallit)
{
    int seg;

    /*
     * We must have an initial default: let's make it 16.
     */
    if (!name)
        *bits = 16;

    if (!name) {
        fprintf(ofile, "section_name on init: returning %d\n", init_seg);
        seg = init_seg;
    } else {
        int n = strcspn(name, " \t");
        char *sname = nasm_strndup(name, n);
        char *tail = nasm_skip_spaces(name+n);
        struct Section *s;

        seg = NO_SEG;
        for (s = dbgsect; s; s = s->next)
            if (!strcmp(s->name, sname))
                seg = s->number;

        if (seg == NO_SEG) {
            s = nasm_malloc(sizeof(*s));
            s->name = sname;
            s->number = seg = seg_alloc();
            s->next = dbgsect;
            dbgsect = s;
            fprintf(ofile, "%s %s (%s) pass %"PRId64" (%s) : returning %d\n",
                    whatwecallit, name, tail, pass_count(), pass_type_name(), seg);

            if (section_labels)
                backend_label(s->name, s->number + 1, 0);
        }
    }
    return seg;
}

static int32_t dbg_section_names(char *name, int *bits)
{
    return dbg_add_section(name, bits, "section_names");
}

static int32_t dbg_herelabel(const char *name, enum label_type type,
                             int32_t oldseg, int32_t *subsection,
                             bool *copyoffset)
{
    int32_t newseg = oldseg;

    if (subsections_via_symbols && type != LBL_LOCAL) {
        newseg = *subsection;
        if (newseg == NO_SEG) {
            newseg = *subsection = seg_alloc();
            *copyoffset = true; /* Minic MachO for now */
        }
    }
    fprintf(ofile, "herelabel %s type %d (seg %08x) -> %08x\n",
            name, type, oldseg, newseg);

    return newseg;
}

static void dbg_deflabel(char *name, int32_t segment, int64_t offset,
                         int is_global, char *special)
{
    fprintf(ofile, "deflabel %s := %08"PRIx32":%016"PRIx64" %s (%d)%s%s\n",
            name, segment, offset,
            is_global == 2 ? "common" : is_global ? "global" : "local",
            is_global, special ? ": " : "", special);
}

static const char *out_type(enum out_type type)
{
    static const char *out_types[] = {
        "rawdata",
        "reserve",
        "zerodata",
        "address",
        "reladdr",
        "segment"
    };
    static char invalid_buf[64];

    if (type >= sizeof(out_types)/sizeof(out_types[0])) {
        sprintf(invalid_buf, "[invalid type %d]", type);
        return invalid_buf;
    }

    return out_types[type];
}

static const char *out_flags(enum out_flags flags)
{
    static const char *out_flags[] = {
        "signed",
        "unsigned"
    };
    static char flags_buf[1024];
    unsigned long flv = flags;
    size_t n;
    size_t left = sizeof flags_buf - 1;
    char *p = flags_buf;
    unsigned int i;

    for (i = 0; flv; flv >>= 1, i++) {
        if (flv & 1) {
            if (i < ARRAY_SIZE(out_flags))
                n = snprintf(p, left, "%s,", out_flags[i]);
            else
                n = snprintf(p, left, "%u,", i);
            if (n >= left)
                break;
            left -= n;
            p += n;
        }
    }
    if (p > flags_buf)
        p--;                    /* Delete final comma */
    *p = '\0';

    return flags_buf;
}

static void dbg_legacy_out(const struct out_data *out);

static void dbg_out(const struct out_data *data)
{
    fprintf(ofile,
            "out to %"PRIx32":%"PRIx64" %s(%s) bits %d insoffs %d/%d "
            "size %"PRIu64,
            data->loc.segment, data->loc.offset,
            out_type(data->type), out_flags(data->flags),
            data->bits, data->insoffs, data->inslen, data->size);
    if (data->itemp) {
        fprintf(ofile, " ins %s#%u(%d)",
                nasm_insn_names[data->itemp->opcode],
                (unsigned int)
                (data->itemp - nasm_instructions[data->itemp->opcode].temp),
                data->itemp->operands);
    } else {
        fprintf(ofile, " no ins (plain data)");
    }

    if (data->type == OUT_ADDRESS || data->type == OUT_RELADDR ||
        data->type == OUT_SEGMENT) {
        fprintf(ofile, " target %"PRIx32":%"PRIx64,
                data->tsegment, data->toffset);
        if (data->twrt != NO_SEG)
            fprintf(ofile, " wrt %"PRIx32, data->twrt);
    }
    if (data->type == OUT_RELADDR)
        fprintf(ofile, " relbase %"PRIx64, data->relbase);

    putc('\n', ofile);

    if (data->type == OUT_RAWDATA) {
        if ((size_t)data->size != data->size) {
            fprintf(ofile, "  data: <error: impossible size>\n");
        } else if (!data->data) {
            fprintf(ofile, "  data: <error: null pointer>\n");
        } else if (dbg_max_data_dump != -1UL &&
                   data->size > dbg_max_data_dump) {
            fprintf(ofile, "  data: <%"PRIu64" bytes>\n", data->size);
        } else {
            size_t i, j;
            const uint8_t *bytes = data->data;
            for (i = 0; i < data->size; i += 16) {
                fprintf(ofile, "  data:");
                for (j = 0; j < 16; j++) {
                    if (i+j >= data->size)
                        fprintf(ofile, "   ");
                    else
                        fprintf(ofile, "%c%02x",
                                (j == 8) ? '-' : ' ', bytes[i+j]);
                }
                fprintf(ofile,"    ");
                for (j = 0; j < 16; j++) {
                    if (i+j >= data->size) {
                        putc(' ', ofile);
                    } else {
                        if (bytes[i+j] >= 32 && bytes[i+j] <= 126)
                            putc(bytes[i+j], ofile);
                        else
                            putc('.', ofile);
                    }
                }
                putc('\n', ofile);
            }
        }
    }

    /* Show the legacy format data, too. */
    dbg_legacy_out(data);
}

static void dbg_legacy_out(const struct out_data *out)
{
    OUT_LEGACY(out,segto,data,type,size,segment,wrt);
    int32_t ldata;

    if (type == OUT_ADDRESS)
        fprintf(ofile, "  legacy: out to %"PRIx32", len = %d: ",
                segto, (int)abs((int)size));
    else
        fprintf(ofile, "  legacy: out to %"PRIx32", len = %"PRId64" (0x%"PRIx64"): ",
                segto, (int64_t)size, size);

    switch (type) {
    case OUT_RESERVE:
        fprintf(ofile, "reserved.\n");
        break;
    case OUT_RAWDATA:
        fprintf(ofile, "rawdata\n"); /* Already have a data dump */
        break;
    case OUT_ADDRESS:
	ldata = *(int64_t *)data;
        fprintf(ofile, "addr %08"PRIx32" (seg %08"PRIx32", wrt %08"PRIx32")\n",
                ldata, segment, wrt);
        break;
    case OUT_REL1ADR:
        fprintf(ofile, "rel1adr %02"PRIx8" (seg %08"PRIx32")\n",
		(uint8_t)*(int64_t *)data, segment);
        break;
    case OUT_REL2ADR:
        fprintf(ofile, "rel2adr %04"PRIx16" (seg %08"PRIx32")\n",
		(uint16_t)*(int64_t *)data, segment);
        break;
    case OUT_REL4ADR:
        fprintf(ofile, "rel4adr %08"PRIx32" (seg %08"PRIx32")\n",
		(uint32_t)*(int64_t *)data,
                segment);
        break;
    case OUT_REL8ADR:
        fprintf(ofile, "rel8adr %016"PRIx64" (seg %08"PRIx32")\n",
		(uint64_t)*(int64_t *)data, segment);
        break;
    default:
        fprintf(ofile, "unknown\n");
        break;
    }
}

static void dbg_sectalign(int32_t seg, unsigned int value)
{
    fprintf(ofile, "set alignment (%d) for segment (%u)\n",
            seg, value);
}

static enum directive_result
dbg_directive(enum directive directive, char *value)
{
    switch (directive) {
        /*
         * The .obj GROUP directive is nontrivial to emulate in a macro.
         * It effectively creates a "pseudo-section" containing the first
         * space-separated argument; the rest we ignore.
         */
    case D_GROUP:
    {
        int dummy;
        dbg_add_section(value, &dummy, "directive:group");
        break;
    }

    default:
        break;
    }

    fprintf(ofile, "directive [%s] value [%s] pass %"PRId64" (%s)\n",
            directive_dname(directive), value, pass_count(), pass_type_name());

    /* The debug output format accepts all known directives */
    return DIRR_OK;
}

static enum directive_result
dbg_pragma(const struct pragma *pragma);

static const struct pragma_facility dbg_pragma_list[] = {
    { NULL, dbg_pragma }
};

static enum directive_result
dbg_pragma(const struct pragma *pragma)
{
    fprintf(ofile, "pragma %s(%s) %s[%s] %s\n",
            pragma->facility_name,
            pragma->facility->name ? pragma->facility->name : "<default>",
            pragma->opname, directive_dname(pragma->opcode),
            pragma->tail);

    if (pragma->facility == &dbg_pragma_list[0]) {
        switch (pragma->opcode) {
        case D_MAXDUMP:
            if (!nasm_stricmp(pragma->tail, "unlimited")) {
                dbg_max_data_dump = -1UL;
            } else {
                char *ep;
                unsigned long arg;

                errno = 0;
                arg = strtoul(pragma->tail, &ep, 0);
                if (errno || *nasm_skip_spaces(ep)) {
                    nasm_warn(WARN_PRAGMA_BAD | ERR_PASS2,
                               "invalid %%pragma dbg maxdump argument");
                    return DIRR_ERROR;
                } else {
                    dbg_max_data_dump = arg;
                }
            }
            break;
        case D_NOSECLABELS:
            section_labels = false;
            break;
        case D_SUBSECTIONS_VIA_SYMBOLS:
            subsections_via_symbols = true;
            break;
        default:
            break;
        }
    }
    return DIRR_OK;
}

static const char *type_name(uint32_t type)
{
    switch (TYM_TYPE(type)) {
    case TY_UNKNOWN:
        return "unknown";
    case TY_LABEL:
        return "label";
    case TY_BYTE:
        return "byte";
    case TY_WORD:
        return "word";
    case TY_DWORD:
        return "dword";
    case TY_FLOAT:
        return "float";
    case TY_QWORD:
        return "qword";
    case TY_TBYTE:
        return "tbyte";
    case TY_OWORD:
        return "oword";
    case TY_YWORD:
        return "yword";
    case TY_ZWORD:
        return "zword";
    case TY_COMMON:
        return "common";
    case TY_SEG:
        return "seg";
    case TY_EXTERN:
        return "extern";
    case TY_EQU:
        return "equ";
    default:
        return "<invalid type code>";
    }
}

static void dbgdbg_init(void)
{
    fprintf(ofile, "dbg init: debug information enabled\n");
}
static void dbgdbg_cleanup(void)
{
    fprintf(ofile, "dbg cleanup: called\n");
}

static void dbgdbg_linnum(const char *lnfname, int32_t lineno, int32_t segto)
{
    fprintf(ofile, "dbg linenum: %s(%"PRId32") segment %"PRIx32"\n",
	    lnfname, lineno, segto);
}
static void dbgdbg_deflabel(char *name, int32_t segment,
                            int64_t offset, int is_global, char *special)
{
    fprintf(ofile, "dbg deflabel: %s = %08"PRIx32":%016"PRIx64" %s (%d)%s%s\n",
            name,
            segment, offset,
            is_global == 2 ? "common" : is_global ? "global" : "local",
            is_global, special ? ": " : "", special);
}

static void dbgdbg_debug_smacros(bool define, const char *def)
{
    fprintf(ofile, "dbg define: %s [%s]\n",
            define ? "define " : "undef ", def);
}
static void dbgdbg_debug_include(bool start, struct src_location outer,
                                 struct src_location inner)
{
    fprintf(ofile, "dbg include: %s include: %s:%"PRId32" %s %s:%"PRId32"\n",
            start ? "start" : "end", outer.filename, outer.lineno,
            start ? "->" : "<-", inner.filename, inner.lineno);
}

static void dbgdbg_output(int output_type, void *param)
{
    (void)output_type;
    (void)param;
    fprintf(ofile, "dbg output: called\n");
}
static void dbgdbg_typevalue(int32_t type)
{
    fprintf(ofile, "dbg typevalue: %s(%"PRIX32")\n",
            type_name(type), TYM_ELEMENTS(type));
}

static void
write_macro_inv_list(const struct debug_macro_inv *inv, int level)
{
    int indent = (level+1) << 1;

    while (inv) {
        const struct rbtree *rb;

        fprintf(ofile, "%*smacro: %s, invoked at %s:%"PRId32
                ", %"PRIu32" ranges\n",
                indent, "", inv->def->name, inv->where.filename,
                inv->where.lineno, inv->naddr);

        for (rb = rb_first(inv->addr.tree); rb; rb = rb_next(rb)) {
            const struct debug_macro_addr *addr =
                (const struct debug_macro_addr *)rb;
            if (!addr->len) {
                fprintf(ofile, "%*s%08"PRIx32": empty\n",
                        indent+2, "", debug_macro_seg(addr));
            } else {
                fprintf(ofile,
                        "%*s%08"PRIx32":[%016"PRIx64" ... %016"PRIx64"] "
                        "len %"PRIu64"\n",
                        indent+2, "",
                        debug_macro_seg(addr), addr->start,
                        addr->start + addr->len - 1, addr->len);
            }
        }

        write_macro_inv_list(inv->down.l, level+1);
        inv = inv->next;
    }
}

static void dbgdbg_debug_mmacros(const struct debug_macro_info *dmi)
{
    const struct debug_macro_def *def;

    fprintf(ofile, "dbg macros: %llu macros defined\n",
            (unsigned long long)dmi->def.n);

    fprintf(ofile, "  macro definitions:\n");
    list_for_each(def, dmi->def.l) {
        fprintf(ofile, "    macro: %s, count %llu, defined at %s:%"PRId32"\n",
                def->name, (unsigned long long)def->ninv,
                def->where.filename, def->where.lineno);
    }

    fprintf(ofile, "  macro invocations:\n");
    write_macro_inv_list(dmi->inv.l, 1);

    fprintf(ofile, "  end macro debug information\n");
}

static void dbgdbg_debug_directive(const char *id, const char *value)
{
    fprintf(ofile, "dbg directive: id [%s] value [%s] pass %"PRId64" (%s)\n",
            id, value, pass_count(), pass_type_name());
}


static const struct pragma_facility dbgdbg_pragma_list[] = {
    { "dbgdbg", dbg_pragma },
    { NULL, dbg_pragma }        /* Won't trigger, "debug" is a reserved ns */
};

static const struct dfmt debug_debug_form = {
    "Trace of all info passed to debug stage",
    "debug",
    dbgdbg_init,
    dbgdbg_linnum,
    dbgdbg_deflabel,
    dbgdbg_debug_smacros,
    dbgdbg_debug_include,
    dbgdbg_debug_mmacros,
    dbgdbg_debug_directive,
    dbgdbg_typevalue,
    dbgdbg_output,
    dbgdbg_cleanup,
    dbgdbg_pragma_list
};

static const struct dfmt * const debug_debug_arr[3] = {
    &debug_debug_form,
    &null_debug_form,
    NULL
};

extern macros_t dbg_stdmac[];

const struct ofmt of_dbg = {
    "Trace of all info passed to output stage",
    "dbg",
    ".dbg",
    OFMT_TEXT|OFMT_KEEP_ADDR,
    64,
    debug_debug_arr,
    &debug_debug_form,
    dbg_stdmac,
    dbg_init,
    dbg_reset,
    dbg_out,
    dbg_deflabel,
    dbg_section_names,
    dbg_herelabel,
    dbg_sectalign,
    null_segbase,
    dbg_directive,
    dbg_cleanup,
    dbg_pragma_list
};

#endif                          /* OF_DBG */