2 * GAS like assembler for TCC
4 * Copyright (c) 2001-2004 Fabrice Bellard
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 ST_FUNC
int asm_get_local_label_name(TCCState
*s1
, unsigned int n
)
28 snprintf(buf
, sizeof(buf
), "L..%u", n
);
29 ts
= tok_alloc(buf
, strlen(buf
));
33 ST_FUNC
void asm_expr(TCCState
*s1
, ExprValue
*pe
);
35 /* We do not use the C expression parser to handle symbols. Maybe the
36 C expression parser could be tweaked to do so. */
38 static void asm_expr_unary(TCCState
*s1
, ExprValue
*pe
)
47 n
= strtoul(p
, (char **)&p
, 0);
48 if (*p
== 'b' || *p
== 'f') {
49 /* backward or forward label */
50 label
= asm_get_local_label_name(s1
, n
);
51 sym
= label_find(label
);
53 /* backward : find the last corresponding defined label */
54 if (sym
&& sym
->r
== 0)
57 error("local label '%d' not found backward", n
);
61 /* if the last label is defined, then define a new one */
62 sym
= label_push(&s1
->asm_labels
, label
, 0);
63 sym
->type
.t
= VT_STATIC
| VT_VOID
;
68 } else if (*p
== '\0') {
72 error("invalid number syntax");
78 asm_expr_unary(s1
, pe
);
84 asm_expr_unary(s1
, pe
);
86 error("invalid operation with label");
104 if (tok
>= TOK_IDENT
) {
105 /* label case : if the label was not found, add one */
106 sym
= label_find(tok
);
108 sym
= label_push(&s1
->asm_labels
, tok
, 0);
109 /* NOTE: by default, the symbol is global */
110 sym
->type
.t
= VT_VOID
;
112 if (sym
->r
== SHN_ABS
) {
113 /* if absolute symbol, no need to put a symbol value */
122 error("bad expression syntax [%s]", get_tok_str(tok
, &tokc
));
128 static void asm_expr_prod(TCCState
*s1
, ExprValue
*pe
)
133 asm_expr_unary(s1
, pe
);
136 if (op
!= '*' && op
!= '/' && op
!= '%' &&
137 op
!= TOK_SHL
&& op
!= TOK_SAR
)
140 asm_expr_unary(s1
, &e2
);
141 if (pe
->sym
|| e2
.sym
)
142 error("invalid operation with label");
150 error("division by zero");
170 static void asm_expr_logic(TCCState
*s1
, ExprValue
*pe
)
175 asm_expr_prod(s1
, pe
);
178 if (op
!= '&' && op
!= '|' && op
!= '^')
181 asm_expr_prod(s1
, &e2
);
182 if (pe
->sym
|| e2
.sym
)
183 error("invalid operation with label");
199 static inline void asm_expr_sum(TCCState
*s1
, ExprValue
*pe
)
204 asm_expr_logic(s1
, pe
);
207 if (op
!= '+' && op
!= '-')
210 asm_expr_logic(s1
, &e2
);
212 if (pe
->sym
!= NULL
&& e2
.sym
!= NULL
)
213 goto cannot_relocate
;
215 if (pe
->sym
== NULL
&& e2
.sym
!= NULL
)
219 /* NOTE: we are less powerful than gas in that case
220 because we store only one symbol in the expression */
221 if (!pe
->sym
&& !e2
.sym
) {
223 } else if (pe
->sym
&& !e2
.sym
) {
225 } else if (pe
->sym
&& e2
.sym
) {
226 if (pe
->sym
== e2
.sym
) {
228 } else if (pe
->sym
->r
== e2
.sym
->r
&& pe
->sym
->r
!= 0) {
229 /* we also accept defined symbols in the same section */
230 pe
->v
+= pe
->sym
->jnext
- e2
.sym
->jnext
;
232 goto cannot_relocate
;
234 pe
->sym
= NULL
; /* same symbols can be substracted to NULL */
237 error("invalid operation with label");
243 ST_FUNC
void asm_expr(TCCState
*s1
, ExprValue
*pe
)
245 asm_expr_sum(s1
, pe
);
248 ST_FUNC
int asm_int_expr(TCCState
*s1
)
257 /* NOTE: the same name space as C labels is used to avoid using too
258 much memory when storing labels in TokenStrings */
259 static void asm_new_label1(TCCState
*s1
, int label
, int is_local
,
260 int sh_num
, int value
)
264 sym
= label_find(label
);
267 /* the label is already defined */
269 error("assembler label '%s' already defined",
270 get_tok_str(label
, NULL
));
272 /* redefinition of local labels is possible */
278 sym
= label_push(&s1
->asm_labels
, label
, 0);
279 sym
->type
.t
= VT_STATIC
| VT_VOID
;
285 static void asm_new_label(TCCState
*s1
, int label
, int is_local
)
287 asm_new_label1(s1
, label
, is_local
, cur_text_section
->sh_num
, ind
);
290 static void asm_free_labels(TCCState
*st
)
295 for(s
= st
->asm_labels
; s
!= NULL
; s
= s1
) {
297 /* define symbol value in object file */
302 sec
= st
->sections
[s
->r
];
303 put_extern_sym2(s
, sec
, s
->jnext
, 0, 0);
306 table_ident
[s
->v
- TOK_IDENT
]->sym_label
= NULL
;
309 st
->asm_labels
= NULL
;
312 static void use_section1(TCCState
*s1
, Section
*sec
)
314 cur_text_section
->data_offset
= ind
;
315 cur_text_section
= sec
;
316 ind
= cur_text_section
->data_offset
;
319 static void use_section(TCCState
*s1
, const char *name
)
322 sec
= find_section(s1
, name
);
323 use_section1(s1
, sec
);
326 static void asm_parse_directive(TCCState
*s1
)
328 int n
, offset
, v
, size
, tok1
;
332 /* assembler directive */
334 sec
= cur_text_section
;
341 n
= asm_int_expr(s1
);
342 if (tok1
== TOK_ASM_align
) {
343 if (n
< 0 || (n
& (n
-1)) != 0)
344 error("alignment must be a positive power of two");
345 offset
= (ind
+ n
- 1) & -n
;
347 /* the section must have a compatible alignment */
348 if (sec
->sh_addralign
< n
)
349 sec
->sh_addralign
= n
;
356 v
= asm_int_expr(s1
);
359 if (sec
->sh_type
!= SHT_NOBITS
) {
360 sec
->data_offset
= ind
;
361 ptr
= section_ptr_add(sec
, size
);
362 memset(ptr
, v
, size
);
373 if (tok
!= TOK_PPNUM
) {
375 error("64 bit constant");
377 vl
= strtoll(p
, (char **)&p
, 0);
381 if (sec
->sh_type
!= SHT_NOBITS
) {
382 /* XXX: endianness */
408 if (sec
->sh_type
!= SHT_NOBITS
) {
429 int repeat
, size
, val
, i
, j
;
430 uint8_t repeat_buf
[8];
432 repeat
= asm_int_expr(s1
);
434 error("repeat < 0; .fill ignored");
441 size
= asm_int_expr(s1
);
443 error("size < 0; .fill ignored");
450 val
= asm_int_expr(s1
);
453 /* XXX: endianness */
455 repeat_buf
[1] = val
>> 8;
456 repeat_buf
[2] = val
>> 16;
457 repeat_buf
[3] = val
>> 24;
462 for(i
= 0; i
< repeat
; i
++) {
463 for(j
= 0; j
< size
; j
++) {
473 /* XXX: handle section symbols too */
474 n
= asm_int_expr(s1
);
476 error("attempt to .org backwards");
488 sym
= label_find(tok
);
490 sym
= label_push(&s1
->asm_labels
, tok
, 0);
491 sym
->type
.t
= VT_VOID
;
493 sym
->type
.t
&= ~VT_STATIC
;
508 expect("string constant");
510 size
= tokc
.cstr
->size
;
511 if (t
== TOK_ASM_ascii
&& size
> 0)
513 for(i
= 0; i
< size
; i
++)
518 } else if (tok
!= TOK_STR
) {
532 if (tok
!= ';' && tok
!= TOK_LINEFEED
) {
533 n
= asm_int_expr(s1
);
536 sprintf(sname
, (n
?".%s%d":".%s"), get_tok_str(tok1
, NULL
), n
);
537 use_section(s1
, sname
);
544 /* XXX: support more options */
547 while (tok
!= ';' && tok
!= TOK_LINEFEED
&& tok
!= ',') {
549 pstrcat(sname
, sizeof(sname
), tokc
.cstr
->data
);
551 pstrcat(sname
, sizeof(sname
), get_tok_str(tok
, NULL
));
555 /* skip section options */
558 expect("string constant");
561 last_text_section
= cur_text_section
;
562 use_section(s1
, sname
);
565 case TOK_ASM_previous
:
569 if (!last_text_section
)
570 error("no previous section referenced");
571 sec
= cur_text_section
;
572 use_section1(s1
, last_text_section
);
573 last_text_section
= sec
;
576 #ifdef TCC_TARGET_I386
590 #ifdef TCC_TARGET_X86_64
591 /* added for compatibility with GAS */
597 error("unknown assembler directive '.%s'", get_tok_str(tok
, NULL
));
603 /* assemble a file */
604 static int tcc_assemble_internal(TCCState
*s1
, int do_preprocess
)
609 /* print stats about opcodes */
614 int nb_op_vals
, i
, j
;
617 memset(freq
, 0, sizeof(freq
));
618 for(pa
= asm_instrs
; pa
->sym
!= 0; pa
++) {
620 for(i
=0;i
<pa
->nb_ops
;i
++) {
621 for(j
=0;j
<nb_op_vals
;j
++) {
622 if (pa
->op_type
[i
] == op_vals
[j
])
625 op_vals
[nb_op_vals
++] = pa
->op_type
[i
];
629 for(i
=0;i
<nb_op_vals
;i
++) {
631 if ((v
& (v
- 1)) != 0)
632 printf("%3d: %08x\n", i
, v
);
634 printf("size=%d nb=%d f0=%d f1=%d f2=%d f3=%d\n",
635 sizeof(asm_instrs
), sizeof(asm_instrs
) / sizeof(ASMInstr
),
636 freq
[0], freq
[1], freq
[2], freq
[3]);
640 /* XXX: undefine C labels */
642 ch
= file
->buf_ptr
[0];
643 tok_flags
= TOK_FLAG_BOL
| TOK_FLAG_BOF
;
644 parse_flags
= PARSE_FLAG_ASM_COMMENTS
;
646 parse_flags
|= PARSE_FLAG_PREPROCESS
;
651 parse_flags
|= PARSE_FLAG_LINEFEED
; /* XXX: suppress that hack */
654 /* horrible gas comment */
655 while (tok
!= TOK_LINEFEED
)
657 } else if (tok
== '.') {
658 asm_parse_directive(s1
);
659 } else if (tok
== TOK_PPNUM
) {
663 n
= strtoul(p
, (char **)&p
, 10);
666 /* new local label */
667 asm_new_label(s1
, asm_get_local_label_name(s1
, n
), 1);
671 } else if (tok
>= TOK_IDENT
) {
672 /* instruction or label */
677 asm_new_label(s1
, opcode
, 0);
680 } else if (tok
== '=') {
683 n
= asm_int_expr(s1
);
684 asm_new_label1(s1
, opcode
, 0, SHN_ABS
, n
);
687 asm_opcode(s1
, opcode
);
691 if (tok
!= ';' && tok
!= TOK_LINEFEED
){
692 expect("end of line");
694 parse_flags
&= ~PARSE_FLAG_LINEFEED
; /* XXX: suppress that hack */
703 /* Assemble the current file */
704 ST_FUNC
int tcc_assemble(TCCState
*s1
, int do_preprocess
)
711 /* default section is text */
712 cur_text_section
= text_section
;
713 ind
= cur_text_section
->data_offset
;
715 define_start
= define_stack
;
717 /* an elf symbol of type STT_FILE must be put so that STB_LOCAL
718 symbols can be safely used */
719 put_elf_sym(symtab_section
, 0, 0,
720 ELFW(ST_INFO
)(STB_LOCAL
, STT_FILE
), 0,
721 SHN_ABS
, file
->filename
);
723 ret
= tcc_assemble_internal(s1
, do_preprocess
);
725 cur_text_section
->data_offset
= ind
;
727 free_defines(define_start
);
732 /********************************************************************/
733 /* GCC inline asm support */
735 /* assemble the string 'str' in the current C compilation unit without
736 C preprocessing. NOTE: str is modified by modifying the '\0' at the
738 static void tcc_assemble_inline(TCCState
*s1
, char *str
, int len
)
740 BufferedFile
*bf
, *saved_file
;
741 int saved_parse_flags
;
742 const int *saved_macro_ptr
;
744 bf
= tcc_malloc(sizeof(BufferedFile
));
745 memset(bf
, 0, sizeof(BufferedFile
));
748 bf
->buf_end
= str
+ len
;
750 /* same name as current file so that errors are correctly
752 pstrcpy(bf
->filename
, sizeof(bf
->filename
), file
->filename
);
753 bf
->line_num
= file
->line_num
;
756 saved_parse_flags
= parse_flags
;
757 saved_macro_ptr
= macro_ptr
;
760 tcc_assemble_internal(s1
, 0);
762 parse_flags
= saved_parse_flags
;
763 macro_ptr
= saved_macro_ptr
;
768 /* find a constraint by its number or id (gcc 3 extended
769 syntax). return -1 if not found. Return in *pp in char after the
771 ST_FUNC
int find_constraint(ASMOperand
*operands
, int nb_operands
,
772 const char *name
, const char **pp
)
780 while (isnum(*name
)) {
781 index
= (index
* 10) + (*name
) - '0';
784 if ((unsigned)index
>= nb_operands
)
786 } else if (*name
== '[') {
788 p
= strchr(name
, ']');
790 ts
= tok_alloc(name
, p
- name
);
791 for(index
= 0; index
< nb_operands
; index
++) {
792 if (operands
[index
].id
== ts
->tok
)
809 static void subst_asm_operands(ASMOperand
*operands
, int nb_operands
,
811 CString
*out_str
, CString
*in_str
)
813 int c
, index
, modifier
;
828 if (*str
== 'c' || *str
== 'n' ||
829 *str
== 'b' || *str
== 'w' || *str
== 'h')
831 index
= find_constraint(operands
, nb_operands
, str
, &str
);
833 error("invalid operand reference after %%");
834 op
= &operands
[index
];
838 if ((op
->vt
->r
& VT_VALMASK
) == VT_LLOCAL
&& op
->is_memory
)
841 subst_asm_operand(out_str
, &sv
, modifier
);
844 cstr_ccat(out_str
, c
);
852 static void parse_asm_operands(ASMOperand
*operands
, int *nb_operands_ptr
,
859 nb_operands
= *nb_operands_ptr
;
861 if (nb_operands
>= MAX_ASM_OPERANDS
)
862 error("too many asm operands");
863 op
= &operands
[nb_operands
++];
868 expect("identifier");
874 expect("string constant");
875 op
->constraint
= tcc_malloc(tokc
.cstr
->size
);
876 strcpy(op
->constraint
, tokc
.cstr
->data
);
883 /* we want to avoid LLOCAL case, except when the 'm'
884 constraint is used. Note that it may come from
885 register storage, so we need to convert (reg)
887 if ((vtop
->r
& VT_LVAL
) &&
888 ((vtop
->r
& VT_VALMASK
) == VT_LLOCAL
||
889 (vtop
->r
& VT_VALMASK
) < VT_CONST
) &&
890 !strchr(op
->constraint
, 'm')) {
902 *nb_operands_ptr
= nb_operands
;
906 static void parse_asm_str(CString
*astr
)
909 /* read the string */
911 expect("string constant");
913 while (tok
== TOK_STR
) {
914 /* XXX: add \0 handling too ? */
915 cstr_cat(astr
, tokc
.cstr
->data
);
918 cstr_ccat(astr
, '\0');
921 /* parse the GCC asm() instruction */
922 ST_FUNC
void asm_instr(void)
925 ASMOperand operands
[MAX_ASM_OPERANDS
];
926 int nb_inputs
, nb_outputs
, nb_operands
, i
, must_subst
, out_reg
;
927 uint8_t clobber_regs
[NB_ASM_REGS
];
930 /* since we always generate the asm() instruction, we can ignore
932 if (tok
== TOK_VOLATILE1
|| tok
== TOK_VOLATILE2
|| tok
== TOK_VOLATILE3
) {
935 parse_asm_str(&astr
);
939 memset(clobber_regs
, 0, sizeof(clobber_regs
));
944 parse_asm_operands(operands
, &nb_operands
, 1);
945 nb_outputs
= nb_operands
;
950 parse_asm_operands(operands
, &nb_operands
, 0);
953 /* XXX: handle registers */
957 expect("string constant");
958 asm_clobber(clobber_regs
, tokc
.cstr
->data
);
971 /* NOTE: we do not eat the ';' so that we can restore the current
972 token after the assembler parsing */
975 nb_inputs
= nb_operands
- nb_outputs
;
977 /* save all values in the memory */
980 /* compute constraints */
981 asm_compute_constraints(operands
, nb_operands
, nb_outputs
,
982 clobber_regs
, &out_reg
);
984 /* substitute the operands in the asm string. No substitution is
985 done if no operands (GCC behaviour) */
987 printf("asm: \"%s\"\n", (char *)astr
.data
);
990 subst_asm_operands(operands
, nb_operands
, nb_outputs
, &astr1
, &astr
);
996 printf("subst_asm: \"%s\"\n", (char *)astr1
.data
);
1000 asm_gen_code(operands
, nb_operands
, nb_outputs
, 0,
1001 clobber_regs
, out_reg
);
1003 /* assemble the string with tcc internal assembler */
1004 tcc_assemble_inline(tcc_state
, astr1
.data
, astr1
.size
- 1);
1006 /* restore the current C token */
1009 /* store the output values if needed */
1010 asm_gen_code(operands
, nb_operands
, nb_outputs
, 1,
1011 clobber_regs
, out_reg
);
1013 /* free everything */
1014 for(i
=0;i
<nb_operands
;i
++) {
1017 tcc_free(op
->constraint
);
1023 ST_FUNC
void asm_global_instr(void)
1028 parse_asm_str(&astr
);
1030 /* NOTE: we do not eat the ';' so that we can restore the current
1031 token after the assembler parsing */
1036 printf("asm_global: \"%s\"\n", (char *)astr
.data
);
1038 cur_text_section
= text_section
;
1039 ind
= cur_text_section
->data_offset
;
1041 /* assemble the string with tcc internal assembler */
1042 tcc_assemble_inline(tcc_state
, astr
.data
, astr
.size
- 1);
1044 cur_text_section
->data_offset
= ind
;
1046 /* restore the current C token */