NetBoot/vasm-1/output_tos.c
2020-06-20 09:33:04 +08:00

384 lines
9.9 KiB
C

/* output_tos.c Atari TOS executable output driver for vasm */
/* (c) in 2009-2016,2020 by Frank Wille */
#include "vasm.h"
#include "output_tos.h"
#if defined(OUTTOS) && defined(VASM_CPU_M68K)
static char *copyright="vasm tos output module 1.1 (c) 2009-2016,2020 Frank Wille";
int tos_hisoft_dri = 1;
static int tosflags,textbasedsyms;
static int max_relocs_per_atom;
static section *sections[3];
static utaddr secsize[3];
static utaddr secoffs[3];
static utaddr sdabase,lastoffs;
#define SECT_ALIGN 2 /* TOS sections have to be aligned to 16 bits */
static int tos_initwrite(section *sec,symbol *sym)
{
int nsyms = 0;
int i;
/* find exactly one .text, .data and .bss section for a.out */
sections[S_TEXT] = sections[S_DATA] = sections[S_BSS] = NULL;
secsize[S_TEXT] = secsize[S_DATA] = secsize[S_BSS] = 0;
for (; sec; sec=sec->next) {
/* section size is assumed to be in in (sec->pc - sec->org), otherwise
we would have to calculate it from the atoms and store it there */
if ((sec->pc - sec->org) > 0 || (sec->flags & HAS_SYMBOLS)) {
i = get_sec_type(sec);
if (i<S_TEXT || i>S_BSS) {
output_error(3,sec->attr); /* section attributes not supported */
i = S_TEXT;
}
if (!sections[i]) {
sections[i] = sec;
secsize[i] = (get_sec_size(sec) + SECT_ALIGN - 1) /
SECT_ALIGN * SECT_ALIGN;
sec->idx = i; /* section index 0:text, 1:data, 2:bss */
}
else
output_error(7,sec->name);
}
}
max_relocs_per_atom = 1;
secoffs[S_TEXT] = 0;
secoffs[S_DATA] = secsize[S_TEXT] + balign(secsize[S_TEXT],SECT_ALIGN);
secoffs[S_BSS] = secoffs[S_DATA] + secsize[S_DATA] +
balign(secsize[S_DATA],SECT_ALIGN);
/* define small data base as .data+32768 @@@FIXME! */
sdabase = secoffs[S_DATA] + 0x8000;
/* count symbols */
for (; sym; sym=sym->next) {
/* ignore symbols preceded by a '.' and internal symbols */
if (*sym->name!='.' && *sym->name!=' ') {
if (!(sym->flags & (VASMINTERN|COMMON)) && sym->type == LABSYM) {
nsyms++;
if ((strlen(sym->name) > DRI_NAMELEN) && tos_hisoft_dri)
nsyms++; /* extra symbol for long name */
}
}
else {
if (!strcmp(sym->name," TOSFLAGS")) {
if (tosflags == 0) /* not defined by command line? */
tosflags = (int)get_sym_value(sym);
}
sym->flags |= VASMINTERN;
}
}
return no_symbols ? 0 : nsyms;
}
static void tos_header(FILE *f,unsigned long tsize,unsigned long dsize,
unsigned long bsize,unsigned long ssize,
unsigned long flags)
{
PH hdr;
setval(1,hdr.ph_branch,2,0x601a);
setval(1,hdr.ph_tlen,4,tsize);
setval(1,hdr.ph_dlen,4,dsize);
setval(1,hdr.ph_blen,4,bsize);
setval(1,hdr.ph_slen,4,ssize);
setval(1,hdr.ph_magic,4,0);
setval(1,hdr.ph_flags,4,flags);
setval(1,hdr.ph_abs,2,0);
fwdata(f,&hdr,sizeof(PH));
}
static void checkdefined(symbol *sym)
{
if (sym->type == IMPORT)
output_error(6,sym->name);
}
static taddr tos_sym_value(symbol *sym,int textbased)
{
taddr val = get_sym_value(sym);
/* all sections form a contiguous block, so add section offset */
if (textbased && sym->type==LABSYM && sym->sec!=NULL)
val += secoffs[sym->sec->idx];
return val;
}
static int write_reloc68k(atom *a,rlist *rl,int signedval,taddr val)
{
nreloc *nrel;
char *p;
if (rl->type > LAST_STANDARD_RELOC) {
unsupp_reloc_error(rl);
return 0;
}
nrel = (nreloc *)rl->reloc;
if (field_overflow(signedval,nrel->size,val)) {
output_atom_error(12,a,rl->type,(unsigned long)nrel->mask,nrel->sym->name,
(unsigned long)nrel->addend,nrel->size);
return 0;
}
if (a->type == DATA)
p = a->content.db->data + nrel->byteoffset;
else if (a->type == SPACE)
p = (char *)a->content.sb->fill; /* @@@ ignore offset completely? */
else
return 1;
setbits(1,p,(nrel->bitoffset+nrel->size+7)&~7,nrel->bitoffset,nrel->size,val);
return 1;
}
static void do_relocs(taddr pc,atom *a)
/* Try to resolve all relocations in a DATA or SPACE atom.
Very simple implementation which can only handle basic 68k relocs. */
{
int rcnt = 0;
section *sec;
rlist *rl;
if (a->type == DATA)
rl = a->content.db->relocs;
else if (a->type == SPACE)
rl = a->content.sb->relocs;
else
rl = NULL;
while (rl) {
switch (rl->type) {
case REL_SD:
checkdefined(((nreloc *)rl->reloc)->sym);
write_reloc68k(a,rl,1,
(tos_sym_value(((nreloc *)rl->reloc)->sym,1)
+ nreloc_real_addend(rl->reloc)) - sdabase);
break;
case REL_PC:
checkdefined(((nreloc *)rl->reloc)->sym);
write_reloc68k(a,rl,1,
(tos_sym_value(((nreloc *)rl->reloc)->sym,1)
+ nreloc_real_addend(rl->reloc)) -
(pc + ((nreloc *)rl->reloc)->byteoffset));
break;
case REL_ABS:
checkdefined(((nreloc *)rl->reloc)->sym);
sec = ((nreloc *)rl->reloc)->sym->sec;
if (!write_reloc68k(a,rl,0,
secoffs[sec?sec->idx:0] +
((nreloc *)rl->reloc)->addend))
break; /* field overflow */
if (((nreloc *)rl->reloc)->size == 32)
break; /* only support 32-bit absolute */
default:
unsupp_reloc_error(rl);
break;
}
rcnt++;
if (a->type == SPACE)
break; /* all SPACE relocs are identical, one is enough */
rl = rl->next;
}
if (rcnt > max_relocs_per_atom)
max_relocs_per_atom = rcnt;
}
static void tos_writesection(FILE *f,section *sec,taddr sec_align)
{
if (sec) {
utaddr pc = secoffs[sec->idx];
utaddr npc;
atom *a;
for (a=sec->first; a; a=a->next) {
npc = fwpcalign(f,a,sec,pc);
do_relocs(npc,a);
if (a->type == DATA)
fwdata(f,a->content.db->data,a->content.db->size);
else if (a->type == SPACE)
fwsblock(f,a->content.sb);
pc = npc + atom_size(a,sec,npc);
}
fwalign(f,pc,sec_align);
}
}
static void write_dri_sym(FILE *f,char *name,int type,taddr value)
{
struct DRIsym stab;
int longname = (strlen(name) > DRI_NAMELEN) && tos_hisoft_dri;
strncpy(stab.name,name,DRI_NAMELEN);
setval(1,stab.type,sizeof(stab.type),longname?(type|STYP_LONGNAME):type);
setval(1,stab.value,sizeof(stab.value),value);
fwdata(f,&stab,sizeof(struct DRIsym));
if (longname) {
char rest_of_name[sizeof(struct DRIsym)];
memset(rest_of_name,0,sizeof(struct DRIsym));
strncpy(rest_of_name,name+DRI_NAMELEN,sizeof(struct DRIsym));
fwdata(f,rest_of_name,sizeof(struct DRIsym));
}
}
static void tos_symboltable(FILE *f,symbol *sym)
{
static int labtype[] = { STYP_TEXT,STYP_DATA,STYP_BSS };
int t;
for (; sym; sym=sym->next) {
/* The Devpac DRI symbol table in executables contains all labels,
no matter if global or local. But no equates or other types. */
if (!(sym->flags & (VASMINTERN|COMMON)) && sym->type == LABSYM) {
if (sym->flags & WEAK)
output_error(10,sym->name); /* weak symbol not supported */
t = labtype[sym->sec->idx] | STYP_DEFINED | STYP_GLOBAL;
write_dri_sym(f,sym->name,t,tos_sym_value(sym,textbasedsyms));
}
}
}
static int offscmp(const void *offs1,const void *offs2)
{
return *(int *)offs1 - *(int *)offs2;
}
static int tos_writerelocs(FILE *f,section *sec)
{
int n = 0;
int *sortoffs = mymalloc(max_relocs_per_atom*sizeof(int));
if (sec) {
utaddr pc = secoffs[sec->idx];
utaddr npc;
atom *a;
rlist *rl;
for (a=sec->first; a; a=a->next) {
int nrel=0;
npc = pcalign(a,pc);
if (a->type == DATA)
rl = a->content.db->relocs;
else if (a->type == SPACE)
rl = a->content.sb->relocs;
else
rl = NULL;
while (rl) {
if (rl->type==REL_ABS && ((nreloc *)rl->reloc)->size==32)
sortoffs[nrel++] = ((nreloc *)rl->reloc)->byteoffset;
rl = rl->next;
}
if (nrel) {
int i;
/* first sort the atom's relocs */
if (nrel > 1)
qsort(sortoffs,nrel,sizeof(int),offscmp);
/* write differences between them */
n += nrel;
for (i=0; i<nrel; i++) {
utaddr newoffs = npc + sortoffs[i];
if (lastoffs) {
/* determine 8bit difference to next relocation */
taddr diff = newoffs - lastoffs;
if (diff < 0)
ierror(0);
while (diff > 254) {
fw8(f,1);
diff -= 254;
}
fw8(f,(uint8_t)diff);
}
else /* first entry is a 32 bits offset */
fw32(f,newoffs,1);
lastoffs = newoffs;
}
}
pc = npc + atom_size(a,sec,npc);
}
}
myfree(sortoffs);
return n;
}
static void write_output(FILE *f,section *sec,symbol *sym)
{
int nsyms = tos_initwrite(sec,sym);
int nrelocs = 0;
tos_header(f,secsize[S_TEXT],secsize[S_DATA],secsize[S_BSS],
nsyms*sizeof(struct DRIsym),tosflags);
tos_writesection(f,sections[S_TEXT],SECT_ALIGN);
tos_writesection(f,sections[S_DATA],SECT_ALIGN);
if (nsyms)
tos_symboltable(f,sym);
nrelocs += tos_writerelocs(f,sections[S_TEXT]);
nrelocs += tos_writerelocs(f,sections[S_DATA]);
if (nrelocs)
fw8(f,0);
else
fw32(f,0,1);
}
static int output_args(char *p)
{
if (!strncmp(p,"-tos-flags=",11)) {
tosflags = atoi(p+11);
return 1;
}
else if (!strcmp(p,"-monst")) {
textbasedsyms = 1;
return 1;
}
return 0;
}
int init_output_tos(char **cp,void (**wo)(FILE *,section *,symbol *),
int (**oa)(char *))
{
*cp = copyright;
*wo = write_output;
*oa = output_args;
unnamed_sections = 1; /* output format doesn't support named sections */
secname_attr = 1;
return 1;
}
#else
int init_output_tos(char **cp,void (**wo)(FILE *,section *,symbol *),
int (**oa)(char *))
{
return 0;
}
#endif