/*
 * YASM assembler virtual line mapping handling (for parse stage)
 *
 *  Copyright (C) 2002-2007  Peter Johnson
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND OTHER CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR OTHER CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
#define YASM_LIB_INTERNAL
#include "util.h"
/*@unused@*/ RCSID("$Id$");

#include "coretype.h"
#include "hamt.h"

#include "errwarn.h"
#include "linemap.h"


/* Source lines tracking */
typedef struct {
    struct line_mapping *vector;
    unsigned long size;
    unsigned long allocated;
} line_mapping_head;

typedef struct line_mapping {
    /* monotonically increasing virtual line */
    unsigned long line;

    /* related info */
    /* "original" source filename */
    /*@null@*/ /*@dependent@*/ const char *filename;
    /* "original" source base line number */
    unsigned long file_line;
    /* "original" source line number increment (for following lines) */
    unsigned long line_inc;
} line_mapping;

typedef struct line_source_info {
    /* first bytecode on line; NULL if no bytecodes on line */
    /*@null@*/ /*@dependent@*/ yasm_bytecode *bc;

    /* source code line */
    /*@owned@*/ char *source;
} line_source_info;

struct yasm_linemap {
    /* Shared storage for filenames */
    /*@only@*/ /*@null@*/ HAMT *filenames;

    /* Current virtual line number. */
    unsigned long current;

    /* Mappings from virtual to physical line numbers */
    /*@only@*/ /*@null@*/ line_mapping_head *map;

    /* Bytecode and source line information */
    /*@only@*/ line_source_info *source_info;
    size_t source_info_size;
};

static void
filename_delete_one(/*@only@*/ void *d)
{
    yasm_xfree(d);
}

void
yasm_linemap_set(yasm_linemap *linemap, const char *filename,
		 unsigned long file_line, unsigned long line_inc)
{
    char *copy;
    int replace = 0;
    line_mapping *mapping;

    /* Create a new mapping in the map */
    if (linemap->map->size >= linemap->map->allocated) {
	/* allocate another size bins when full for 2x space */
	linemap->map->vector =
	    yasm_xrealloc(linemap->map->vector, 2*linemap->map->allocated
			  *sizeof(line_mapping));
	linemap->map->allocated *= 2;
    }
    mapping = &linemap->map->vector[linemap->map->size];
    linemap->map->size++;

    /* Fill it */

    if (!filename) {
	if (linemap->map->size >= 2)
	    mapping->filename =
		linemap->map->vector[linemap->map->size-2].filename;
	else
	    filename = "unknown";
    }
    if (filename) {
	/* Copy the filename (via shared storage) */
	copy = yasm__xstrdup(filename);
	/*@-aliasunique@*/
	mapping->filename = HAMT_insert(linemap->filenames, copy, copy,
					&replace, filename_delete_one);
	/*@=aliasunique@*/
    }

    mapping->line = linemap->current;
    mapping->file_line = file_line;
    mapping->line_inc = line_inc;
}

unsigned long
yasm_linemap_poke(yasm_linemap *linemap, const char *filename,
		  unsigned long file_line)
{
    unsigned long line;
    line_mapping *mapping;

    linemap->current++;
    yasm_linemap_set(linemap, filename, file_line, 0);

    mapping = &linemap->map->vector[linemap->map->size-1];

    line = linemap->current;

    linemap->current++;
    yasm_linemap_set(linemap, mapping->filename, mapping->file_line,
		     mapping->line_inc);

    return line;
}

yasm_linemap *
yasm_linemap_create(void)
{
    size_t i;
    yasm_linemap *linemap = yasm_xmalloc(sizeof(yasm_linemap));

    linemap->filenames = HAMT_create(0, yasm_internal_error_);

    linemap->current = 1;

    /* initialize mapping vector */
    linemap->map = yasm_xmalloc(sizeof(line_mapping_head));
    linemap->map->vector = yasm_xmalloc(8*sizeof(line_mapping));
    linemap->map->size = 0;
    linemap->map->allocated = 8;
    
    /* initialize source line information array */
    linemap->source_info_size = 2;
    linemap->source_info = yasm_xmalloc(linemap->source_info_size *
					sizeof(line_source_info));
    for (i=0; i<linemap->source_info_size; i++) {
	linemap->source_info[i].bc = NULL;
	linemap->source_info[i].source = NULL;
    }

    return linemap;
}

void
yasm_linemap_destroy(yasm_linemap *linemap)
{
    size_t i;
    for (i=0; i<linemap->source_info_size; i++) {
	if (linemap->source_info[i].source)
	    yasm_xfree(linemap->source_info[i].source);
    }
    yasm_xfree(linemap->source_info);

    if (linemap->map) {
	yasm_xfree(linemap->map->vector);
	yasm_xfree(linemap->map);
    }

    if (linemap->filenames)
	HAMT_destroy(linemap->filenames, filename_delete_one);

    yasm_xfree(linemap);
}

unsigned long
yasm_linemap_get_current(yasm_linemap *linemap)
{
    return linemap->current;
}

void
yasm_linemap_add_source(yasm_linemap *linemap, yasm_bytecode *bc,
			const char *source)
{
    size_t i;

    while (linemap->current > linemap->source_info_size) {
	/* allocate another size bins when full for 2x space */
	linemap->source_info = yasm_xrealloc(linemap->source_info,
	    2*linemap->source_info_size*sizeof(line_source_info));
	for (i=linemap->source_info_size; i<linemap->source_info_size*2; i++) {
	    linemap->source_info[i].bc = NULL;
	    linemap->source_info[i].source = NULL;
	}
	linemap->source_info_size *= 2;
    }

    /* Delete existing info for that line (if any) */
    if (linemap->source_info[linemap->current-1].source)
	yasm_xfree(linemap->source_info[linemap->current-1].source);

    linemap->source_info[linemap->current-1].bc = bc;
    linemap->source_info[linemap->current-1].source = yasm__xstrdup(source);
}

unsigned long
yasm_linemap_goto_next(yasm_linemap *linemap)
{
    return ++(linemap->current);
}

void
yasm_linemap_lookup(yasm_linemap *linemap, unsigned long line,
		    const char **filename, unsigned long *file_line)
{
    line_mapping *mapping;
    unsigned long vindex, step;

    assert(line <= linemap->current);

    /* Binary search through map to find highest line_index <= index */
    assert(linemap->map != NULL);
    vindex = 0;
    /* start step as the greatest power of 2 <= size */
    step = 1;
    while (step*2<=linemap->map->size)
	step*=2;
    while (step>0) {
	if (vindex+step < linemap->map->size
		&& linemap->map->vector[vindex+step].line <= line)
	    vindex += step;
	step /= 2;
    }
    mapping = &linemap->map->vector[vindex];

    *filename = mapping->filename;
    *file_line = mapping->file_line + mapping->line_inc*(line-mapping->line);
}

int
yasm_linemap_traverse_filenames(yasm_linemap *linemap, /*@null@*/ void *d,
				int (*func) (const char *filename, void *d))
{
    return HAMT_traverse(linemap->filenames, d, (int (*) (void *, void *))func);
}

int
yasm_linemap_get_source(yasm_linemap *linemap, unsigned long line,
			yasm_bytecode **bcp, const char **sourcep)
{
    if (line > linemap->source_info_size) {
	*bcp = NULL;
	*sourcep = NULL;
	return 1;
    }

    *bcp = linemap->source_info[line-1].bc;
    *sourcep = linemap->source_info[line-1].source;

    return (!(*sourcep));
}