sparc.c

早期freebsd实现

			if (mask >= 32) {
			    break;
			}
		    } else {
			mask -= '0';
		    }
		    switch (*args) {

		    case 'e':
			opcode |= mask << 14;
			continue;

		    case 'f':
			opcode |= mask;
			continue;

		    case 'g':
			opcode |= mask << 25;
			continue;
		    }
		}
		break;

	    case 'F':
		if (strncmp(s, "%fsr", 4) == 0) {
		    s += 4;
		    continue;
		}
		break;

	    case 'h':       /* high 22 bits */
	        the_insn.reloc = RELOC_HI22;
		goto immediate;

	    case 'l':   /* 22 bit PC relative immediate */
	        the_insn.reloc = RELOC_WDISP22;
		the_insn.pcrel = 1;
		goto immediate;

	    case 'L':   /* 30 bit immediate */
	        the_insn.reloc = RELOC_WDISP30;
		the_insn.pcrel = 1;
		goto immediate;

	    case 'i':   /* 13 bit immediate */
	        the_insn.reloc = RELOC_BASE13;

		/*FALLTHROUGH*/

	    immediate:
		if(*s==' ')
		  s++;
		if (*s == '%') {
		    if ((c = s[1]) == 'h' && s[2] == 'i') {
			the_insn.reloc = RELOC_HI22;
			s+=3;
		    } else if (c == 'l' && s[2] == 'o') {
			the_insn.reloc = RELOC_LO10;
			s+=3;
		    } else
		    	break;
		}
		/* Note that if the getExpression() fails, we will still have
		   created U entries in the symbol table for the 'symbols'
		   in the input string.  Try not to create U symbols for
		   registers, etc. */
		{
			/* This stuff checks to see if the expression ends
			   in +%reg If it does, it removes the register from
			   the expression, and re-sets 's' to point to the
			   right place */

			char *s1;

			for(s1=s;*s1 && *s1!=','&& *s1!=']';s1++)
				;

			if(s1!=s && isdigit(s1[-1])) {
				if(s1[-2]=='%' && s1[-3]=='+') {
					s1-=3;
					*s1='\0';
					(void)getExpression(s);
					*s1='+';
					s=s1;
					continue;
				} else if(index("goli0123456789",s1[-2]) && s1[-3]=='%' && s1[-4]=='+') {
					s1-=4;
					*s1='\0';
					(void)getExpression(s);
					*s1='+';
					s=s1;
					continue;
				}
			}
		}
		(void)getExpression(s);
		s = expr_end;
		continue;

	    case 'a':
		if (*s++ == 'a') {
		    opcode |= ANNUL;
		    continue;
		}
		break;

	    case 'A':       /* alternate space */
		if (isdigit(*s)) {
		    long num;

		    num=0;
		    while (isdigit(*s)) {
			num= num*10 + *s-'0';
			++s;
		    }
		    opcode |= num<<5;
		    continue;
		}
		break;
		/* abort(); */

	    case 'p':
		if (strncmp(s, "%psr", 4) == 0) {
		    s += 4;
		    continue;
		}
		break;

	    case 'q':   /* floating point queue */
		if (strncmp(s, "%fq", 3) == 0) {
		    s += 3;
		    continue;
		}
		break;

	    case 'Q':   /* coprocessor queue */
		if (strncmp(s, "%cq", 3) == 0) {
		    s += 3;
		    continue;
		}
		break;

	    case 'S':
		if (strcmp(str, "set") == 0) {
		    special_case = SPECIAL_CASE_SET;
		    continue;
		}
		break;

	    case 't':
		if (strncmp(s, "%tbr", 4) != 0)
		    break;
		s += 4;
		continue;

	    case 'w':
		if (strncmp(s, "%wim", 4) != 0)
		    break;
		s += 4;
		continue;

	    case 'y':
		if (strncmp(s, "%y", 2) != 0)
		    break;
		s += 2;
		continue;

	    default:
		abort();
	    }
	    break;
	}
	error:
	if (match == FALSE)
	  {
	    /* Args don't match.  */
	    if (&insn[1] - sparc_opcodes < NUMOPCODES
		&& !strcmp(insn->name, insn[1].name))
	      {
		++insn;
		s = argsStart;
		continue;
	      }
	    else
	      {
		as_warn("Illegal operands");
		return;
	      }
	  }
	break;
    }

    the_insn.opcode = opcode;
    return;
}

static int
getExpression(str)
    char *str;
{
    char *save_in;
    segT seg;

    save_in = input_line_pointer;
    input_line_pointer = str;
    switch (seg = expression(&the_insn.exp)) {

    case SEG_ABSOLUTE:
    case SEG_TEXT:
    case SEG_DATA:
    case SEG_BSS:
    case SEG_UNKNOWN:
    case SEG_DIFFERENCE:
    case SEG_BIG:
    case SEG_NONE:
	break;

    default:
	the_insn.error = "bad segment";
	expr_end = input_line_pointer;
	input_line_pointer=save_in;
	return 1;
    }
    expr_end = input_line_pointer;
    input_line_pointer = save_in;
    return 0;
}


/*
    This is identical to the md_atof in m68k.c.  I think this is right,
    but I'm not sure.

   Turn a string in input_line_pointer into a floating point constant of type
   type, and store the appropriate bytes in *litP.  The number of LITTLENUMS
   emitted is stored in *sizeP .  An error message is returned, or NULL on OK.
 */

/* Equal to MAX_PRECISION in atof-ieee.c */
#define MAX_LITTLENUMS 6

char *
md_atof(type,litP,sizeP)
    char type;
    char *litP;
    int *sizeP;
{
    int	prec;
    LITTLENUM_TYPE words[MAX_LITTLENUMS];
    LITTLENUM_TYPE *wordP;
    char	*t;
    char	*atof_ieee();

    switch(type) {

    case 'f':
    case 'F':
    case 's':
    case 'S':
	prec = 2;
	break;

    case 'd':
    case 'D':
    case 'r':
    case 'R':
	prec = 4;
	break;

    case 'x':
    case 'X':
	prec = 6;
	break;

    case 'p':
    case 'P':
	prec = 6;
	break;

    default:
	*sizeP=0;
	return "Bad call to MD_ATOF()";
    }
    t=atof_ieee(input_line_pointer,type,words);
    if(t)
	input_line_pointer=t;
    *sizeP=prec * sizeof(LITTLENUM_TYPE);
    for(wordP=words;prec--;) {
	md_number_to_chars(litP,(long)(*wordP++),sizeof(LITTLENUM_TYPE));
	litP+=sizeof(LITTLENUM_TYPE);
    }
    return "";	/* Someone should teach Dean about null pointers */
}

/*
 * Write out big-endian.
 */
void
md_number_to_chars(buf,val,n)
    char *buf;
    long val;
    int n;
{

    switch(n) {

    case 4:
	*buf++ = val >> 24;
	*buf++ = val >> 16;
    case 2:
	*buf++ = val >> 8;
    case 1:
	*buf = val;
	break;

    default:
	abort();
    }
    return;
}

void
md_number_to_imm(buf,val,n, fixP, seg_type)
    char *buf;
    long val;
    int n;
    fixS *fixP;
    int seg_type;
{
    if (seg_type != N_TEXT || fixP->fx_r_type == NO_RELOC) {
	switch (n) {
	case 1:
		*buf = val;
		break;
	case 2:
		*buf++ = (val>>8);
		*buf = val;
		break;
	case 4:
		*buf++ = (val>>24);
		*buf++ = (val>>16);
		*buf++ = (val>>8);
		*buf = val;
		break;
	default:
		abort();
	}
	return;
    }

    assert(n == 4);
    assert(fixP->fx_r_type < NO_RELOC);

    /*
     * This is a hack.  There should be a better way to
     * handle this.
     */
    if (fixP->fx_r_type == RELOC_WDISP30 && fixP->fx_addsy) {
	    val += fixP->fx_where + fixP->fx_frag->fr_address;
    }

    switch (fixP->fx_r_type) {

    case RELOC_32:
	buf[0] = val >> 24;
	buf[1] = val >> 16;
	buf[2] = val >> 8;
	buf[3] = val;
	break;

#if 0
    case RELOC_8:         /* These don't seem to ever be needed. */
    case RELOC_16:
    case RELOC_DISP8:
    case RELOC_DISP16:
    case RELOC_DISP32:
#endif
    case RELOC_WDISP30:
	val = (val >>= 2) + 1;
	buf[0] |= (val >> 24) & 0x3f;
	buf[1]= (val >> 16);
	buf[2] = val >> 8;
	buf[3] = val;
	break;

    case RELOC_HI22:
	if(!fixP->fx_addsy) {
	  buf[1] |= (val >> 26) & 0x3f;
	  buf[2] = val >> 18;
	  buf[3] = val >> 10;
	} else {
	  buf[2]=0;
	  buf[3]=0;
	}
	break;
#if 0
    case RELOC_22:
    case RELOC_13:
#endif
    case RELOC_LO10:
	if(!fixP->fx_addsy) {
	  buf[2] |= (val >> 8) & 0x03;
	  buf[3] = val;
	} else
	  buf[3]=0;
	break;
#if 0
    case RELOC_SFA_BASE:
    case RELOC_SFA_OFF13:
    case RELOC_BASE10:
#endif
    case RELOC_BASE13:
	buf[2] |= (val >> 8) & 0x1f;
	buf[3] = val;
	break;

    case RELOC_WDISP22:
	val = (val >>= 2) + 1;
	/* FALLTHROUGH */
    case RELOC_BASE22:
	buf[1] |= (val >> 16) & 0x3f;
	buf[2] = val >> 8;
	buf[3] = val;
	break;

#if 0
    case RELOC_PC10: 
    case RELOC_PC22: 
    case RELOC_JMP_TBL:
    case RELOC_SEGOFF16:
    case RELOC_GLOB_DAT:
    case RELOC_JMP_SLOT: 
    case RELOC_RELATIVE:
#endif

    case NO_RELOC:
    default:
	as_warn("bad relocation type: 0x%02x", fixP->fx_r_type);
	break;
    }
    return;
}

/* should never be called for sparc */
void
md_create_short_jump(ptr, from_addr, to_addr, frag, to_symbol)
    char *ptr;
    long from_addr, to_addr;
{
    fprintf(stderr, "sparc_create_short_jmp\n");
    abort();
}

/* should never be called for sparc */
void
md_number_to_disp(buf,val,n)
    char	*buf;
    long	val;
{
    fprintf(stderr, "md_number_to_disp\n");
    abort();
}

/* should never be called for sparc */
void
md_number_to_field(buf,val,fix)
    char *buf;
    long val;
    void *fix;
{
    fprintf(stderr, "sparc_number_to_field\n");
    abort();
}

/* the bit-field entries in the relocation_info struct plays hell 
   with the byte-order problems of cross-assembly.  So as a hack,
   I added this mach. dependent ri twiddler.  Ugly, but it gets
   you there. -KWK */
/* on sparc: first 4 bytes are normal unsigned long address, next three
   bytes are index, most sig. byte first.  Byte 7 is broken up with
   bit 7 as external, bits 6 & 5 unused, and the lower
   five bits as relocation type.  Next 4 bytes are long int addend. */
/* Thanx and a tip of the hat to Michael Bloom, [e-mail] */
void
md_ri_to_chars(ri_p, ri)
     struct reloc_info_sparc *ri_p, ri;
{
  unsigned char the_bytes[sizeof(*ri_p)];
  
  /* this is easy */
  md_number_to_chars(the_bytes, ri.r_address, sizeof(ri.r_address));
  /* now the fun stuff */
  the_bytes[4] = (ri.r_index >> 16) & 0x0ff;
  the_bytes[5] = (ri.r_index >> 8) & 0x0ff;
  the_bytes[6] = ri.r_index & 0x0ff;
  the_bytes[7] = ((ri.r_extern << 7)  & 0x80) | (0 & 0x60) | (ri.r_type & 0x1F);
  /* Also easy */
  md_number_to_chars(&the_bytes[8], ri.r_addend, sizeof(ri.r_addend));
  /* now put it back where you found it, Junior... */
  bcopy (the_bytes, (char *)ri_p, sizeof(*ri_p));
}

/* should never be called for sparc */
void
md_convert_frag(fragP)
    register fragS *fragP;
{
    fprintf(stderr, "sparc_convert_frag\n");
    abort();
}

/* should never be called for sparc */
void
md_create_long_jump(ptr, from_addr, to_addr, frag, to_symbol)
    char	*ptr;
    long	from_addr,
	        to_addr;
    fragS	*frag;
    symbolS	*to_symbol;
{
    fprintf(stderr, "sparc_create_long_jump\n");
    abort();
}

/* should never be called for sparc */
int
md_estimate_size_before_relax(fragP, segtype)
    register fragS *fragP;
{
    fprintf(stderr, "sparc_estimate_size_before_relax\n");
    abort();
    return 0;
}

#if 0
/* for debugging only */
static void
print_insn(insn)
    struct sparc_it *insn;
{
    char *Reloc[] = {
    "RELOC_8",
    "RELOC_16",
    "RELOC_32",
    "RELOC_DISP8",
    "RELOC_DISP16",
    "RELOC_DISP32",
    "RELOC_WDISP30",
    "RELOC_WDISP22",
    "RELOC_HI22",
    "RELOC_22",
    "RELOC_13",
    "RELOC_LO10",
    "RELOC_SFA_BASE",
    "RELOC_SFA_OFF13",
    "RELOC_BASE10",
    "RELOC_BASE13",
    "RELOC_BASE22",
    "RELOC_PC10",
    "RELOC_PC22",
    "RELOC_JMP_TBL",
    "RELOC_SEGOFF16",
    "RELOC_GLOB_DAT",
    "RELOC_JMP_SLOT",
    "RELOC_RELATIVE",
    "NO_RELOC"
    };

    if (insn->error) {
	fprintf(stderr, "ERROR: %s\n");
    }
    fprintf(stderr, "opcode=0x%08x\n", insn->opcode);
    fprintf(stderr, "reloc = %s\n", Reloc[insn->reloc]);
    fprintf(stderr, "exp =  {\n");
    fprintf(stderr, "\t\tX_add_symbol = %s\n",
	insn->exp.X_add_symbol ?
	(insn->exp.X_add_symbol->sy_name ? 
	insn->exp.X_add_symbol->sy_name : "???") : "0");
    fprintf(stderr, "\t\tX_sub_symbol = %s\n",
	insn->exp.X_subtract_symbol ?
	    (insn->exp.X_subtract_symbol->sy_name ? 
	        insn->exp.X_subtract_symbol->sy_name : "???") : "0");
    fprintf(stderr, "\t\tX_add_number = %d\n",
	insn->exp.X_add_number);
    fprintf(stderr, "}\n");
    return;
}
#endif

/*
 * Sparc relocations are completely different, so it needs
 * this machine dependent routine to emit them.
 */
void
emit_relocations(fixP, segment_address_in_file)
    register fixS *fixP;
    relax_addressT segment_address_in_file;
{
    struct reloc_info_sparc ri;
    register symbolS *symbolP;
    extern char *next_object_file_charP;
    long add_number;

    bzero((char *) &ri, sizeof(ri));
    for (; fixP; fixP = fixP->fx_next) {

	if (fixP->fx_r_type >= NO_RELOC) {
	    fprintf(stderr, "fixP->fx_r_type = %d\n", fixP->fx_r_type);
	    abort();
	}

	if ((symbolP = fixP->fx_addsy) != NULL) {
	    ri.r_address = fixP->fx_frag->fr_address +
	        fixP->fx_where - segment_address_in_file;
	    if ((symbolP->sy_type & N_TYPE) == N_UNDF) {
		ri.r_extern = 1;
		ri.r_index = symbolP->sy_number;
	    } else {
		ri.r_extern = 0;
		ri.r_index = symbolP->sy_type & N_TYPE;
	    }
	    if (symbolP && symbolP->sy_frag) {
		ri.r_addend = symbolP->sy_frag->fr_address;
	    }
	    ri.r_type = fixP->fx_r_type;
	    if (fixP->fx_pcrel) {
/*		ri.r_addend -= fixP->fx_where;          */
		ri.r_addend -= ri.r_address;            
	    } else {
		ri.r_addend = fixP->fx_addnumber;
	    }

/*	    md_ri_to_chars((char *) &ri, ri);        */
	    append(&next_object_file_charP, (char *)& ri, sizeof(ri));
	}
    }
    return;
}

int
md_parse_option(argP,cntP,vecP)
    char **argP;
    int *cntP;
    char ***vecP;
{
    return 1;
}