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");
490 sym
= label_find(tok
);
492 sym
= label_push(&s1
->asm_labels
, tok
, 0);
493 sym
->type
.t
= VT_VOID
;
495 sym
->type
.t
&= ~VT_STATIC
;
496 if (tok1
== TOK_ASM_weak
)
497 sym
->type
.t
|= VT_WEAK
;
499 } while (tok
== ',');
512 expect("string constant");
514 size
= tokc
.cstr
->size
;
515 if (t
== TOK_ASM_ascii
&& size
> 0)
517 for(i
= 0; i
< size
; i
++)
522 } else if (tok
!= TOK_STR
) {
536 if (tok
!= ';' && tok
!= TOK_LINEFEED
) {
537 n
= asm_int_expr(s1
);
540 sprintf(sname
, (n
?".%s%d":".%s"), get_tok_str(tok1
, NULL
), n
);
541 use_section(s1
, sname
);
552 pstrcat(filename
, sizeof(filename
), tokc
.cstr
->data
);
554 pstrcat(filename
, sizeof(filename
), get_tok_str(tok
, NULL
));
556 if (s1
->warn_unsupported
)
557 warning("ignoring .file %s", filename
);
570 pstrcat(ident
, sizeof(ident
), tokc
.cstr
->data
);
572 pstrcat(ident
, sizeof(ident
), get_tok_str(tok
, NULL
));
574 if (s1
->warn_unsupported
)
575 warning("ignoring .ident %s", ident
);
585 sym
= label_find(tok
);
587 error("label not found: %s", get_tok_str(tok
, NULL
));
592 /* XXX .size name,label2-label1 */
593 if (s1
->warn_unsupported
)
594 warning("ignoring .size %s,*", get_tok_str(tok
, NULL
));
596 while (tok
!= '\n' && tok
!= CH_EOF
) {
608 sym
= label_find(tok
);
610 sym
= label_push(&s1
->asm_labels
, tok
, 0);
611 sym
->type
.t
= VT_VOID
;
618 pstrcat(newtype
, sizeof(newtype
), tokc
.cstr
->data
);
620 pstrcat(newtype
, sizeof(newtype
), get_tok_str(tok
, NULL
));
622 if (!strcmp(newtype
, "function")) {
623 sym
->type
.t
= VT_FUNC
;
625 else if (s1
->warn_unsupported
)
626 warning("change type of '%s' from 0x%x to '%s' ignored",
627 get_tok_str(sym
->v
, NULL
), sym
->type
.t
, newtype
);
636 /* XXX: support more options */
639 while (tok
!= ';' && tok
!= TOK_LINEFEED
&& tok
!= ',') {
641 pstrcat(sname
, sizeof(sname
), tokc
.cstr
->data
);
643 pstrcat(sname
, sizeof(sname
), get_tok_str(tok
, NULL
));
647 /* skip section options */
650 expect("string constant");
653 last_text_section
= cur_text_section
;
654 use_section(s1
, sname
);
657 case TOK_ASM_previous
:
661 if (!last_text_section
)
662 error("no previous section referenced");
663 sec
= cur_text_section
;
664 use_section1(s1
, last_text_section
);
665 last_text_section
= sec
;
668 #ifdef TCC_TARGET_I386
682 #ifdef TCC_TARGET_X86_64
683 /* added for compatibility with GAS */
689 error("unknown assembler directive '.%s'", get_tok_str(tok
, NULL
));
695 /* assemble a file */
696 static int tcc_assemble_internal(TCCState
*s1
, int do_preprocess
)
701 /* print stats about opcodes */
706 int nb_op_vals
, i
, j
;
709 memset(freq
, 0, sizeof(freq
));
710 for(pa
= asm_instrs
; pa
->sym
!= 0; pa
++) {
712 for(i
=0;i
<pa
->nb_ops
;i
++) {
713 for(j
=0;j
<nb_op_vals
;j
++) {
714 if (pa
->op_type
[i
] == op_vals
[j
])
717 op_vals
[nb_op_vals
++] = pa
->op_type
[i
];
721 for(i
=0;i
<nb_op_vals
;i
++) {
723 if ((v
& (v
- 1)) != 0)
724 printf("%3d: %08x\n", i
, v
);
726 printf("size=%d nb=%d f0=%d f1=%d f2=%d f3=%d\n",
727 sizeof(asm_instrs
), sizeof(asm_instrs
) / sizeof(ASMInstr
),
728 freq
[0], freq
[1], freq
[2], freq
[3]);
732 /* XXX: undefine C labels */
734 ch
= file
->buf_ptr
[0];
735 tok_flags
= TOK_FLAG_BOL
| TOK_FLAG_BOF
;
736 parse_flags
= PARSE_FLAG_ASM_COMMENTS
;
738 parse_flags
|= PARSE_FLAG_PREPROCESS
;
743 parse_flags
|= PARSE_FLAG_LINEFEED
; /* XXX: suppress that hack */
746 /* horrible gas comment */
747 while (tok
!= TOK_LINEFEED
)
749 } else if (tok
== '.') {
750 asm_parse_directive(s1
);
751 } else if (tok
== TOK_PPNUM
) {
755 n
= strtoul(p
, (char **)&p
, 10);
758 /* new local label */
759 asm_new_label(s1
, asm_get_local_label_name(s1
, n
), 1);
763 } else if (tok
>= TOK_IDENT
) {
764 /* instruction or label */
769 asm_new_label(s1
, opcode
, 0);
772 } else if (tok
== '=') {
775 n
= asm_int_expr(s1
);
776 asm_new_label1(s1
, opcode
, 0, SHN_ABS
, n
);
779 asm_opcode(s1
, opcode
);
783 if (tok
!= ';' && tok
!= TOK_LINEFEED
){
784 expect("end of line");
786 parse_flags
&= ~PARSE_FLAG_LINEFEED
; /* XXX: suppress that hack */
795 /* Assemble the current file */
796 ST_FUNC
int tcc_assemble(TCCState
*s1
, int do_preprocess
)
803 /* default section is text */
804 cur_text_section
= text_section
;
805 ind
= cur_text_section
->data_offset
;
807 define_start
= define_stack
;
809 /* an elf symbol of type STT_FILE must be put so that STB_LOCAL
810 symbols can be safely used */
811 put_elf_sym(symtab_section
, 0, 0,
812 ELFW(ST_INFO
)(STB_LOCAL
, STT_FILE
), 0,
813 SHN_ABS
, file
->filename
);
815 ret
= tcc_assemble_internal(s1
, do_preprocess
);
817 cur_text_section
->data_offset
= ind
;
819 free_defines(define_start
);
824 /********************************************************************/
825 /* GCC inline asm support */
827 /* assemble the string 'str' in the current C compilation unit without
828 C preprocessing. NOTE: str is modified by modifying the '\0' at the
830 static void tcc_assemble_inline(TCCState
*s1
, char *str
, int len
)
832 int saved_parse_flags
;
833 const int *saved_macro_ptr
;
835 saved_parse_flags
= parse_flags
;
836 saved_macro_ptr
= macro_ptr
;
838 tcc_open_bf(s1
, file
->filename
, len
);
839 file
->line_num
= file
->prev
->line_num
;
840 memcpy(file
->buffer
, str
, len
);
843 tcc_assemble_internal(s1
, 0);
846 parse_flags
= saved_parse_flags
;
847 macro_ptr
= saved_macro_ptr
;
850 /* find a constraint by its number or id (gcc 3 extended
851 syntax). return -1 if not found. Return in *pp in char after the
853 ST_FUNC
int find_constraint(ASMOperand
*operands
, int nb_operands
,
854 const char *name
, const char **pp
)
862 while (isnum(*name
)) {
863 index
= (index
* 10) + (*name
) - '0';
866 if ((unsigned)index
>= nb_operands
)
868 } else if (*name
== '[') {
870 p
= strchr(name
, ']');
872 ts
= tok_alloc(name
, p
- name
);
873 for(index
= 0; index
< nb_operands
; index
++) {
874 if (operands
[index
].id
== ts
->tok
)
891 static void subst_asm_operands(ASMOperand
*operands
, int nb_operands
,
893 CString
*out_str
, CString
*in_str
)
895 int c
, index
, modifier
;
910 if (*str
== 'c' || *str
== 'n' ||
911 *str
== 'b' || *str
== 'w' || *str
== 'h')
913 index
= find_constraint(operands
, nb_operands
, str
, &str
);
915 error("invalid operand reference after %%");
916 op
= &operands
[index
];
920 if ((op
->vt
->r
& VT_VALMASK
) == VT_LLOCAL
&& op
->is_memory
)
923 subst_asm_operand(out_str
, &sv
, modifier
);
926 cstr_ccat(out_str
, c
);
934 static void parse_asm_operands(ASMOperand
*operands
, int *nb_operands_ptr
,
941 nb_operands
= *nb_operands_ptr
;
943 if (nb_operands
>= MAX_ASM_OPERANDS
)
944 error("too many asm operands");
945 op
= &operands
[nb_operands
++];
950 expect("identifier");
956 expect("string constant");
957 op
->constraint
= tcc_malloc(tokc
.cstr
->size
);
958 strcpy(op
->constraint
, tokc
.cstr
->data
);
965 /* we want to avoid LLOCAL case, except when the 'm'
966 constraint is used. Note that it may come from
967 register storage, so we need to convert (reg)
969 if ((vtop
->r
& VT_LVAL
) &&
970 ((vtop
->r
& VT_VALMASK
) == VT_LLOCAL
||
971 (vtop
->r
& VT_VALMASK
) < VT_CONST
) &&
972 !strchr(op
->constraint
, 'm')) {
984 *nb_operands_ptr
= nb_operands
;
988 /* parse the GCC asm() instruction */
989 ST_FUNC
void asm_instr(void)
992 ASMOperand operands
[MAX_ASM_OPERANDS
];
993 int nb_inputs
, nb_outputs
, nb_operands
, i
, must_subst
, out_reg
;
994 uint8_t clobber_regs
[NB_ASM_REGS
];
997 /* since we always generate the asm() instruction, we can ignore
999 if (tok
== TOK_VOLATILE1
|| tok
== TOK_VOLATILE2
|| tok
== TOK_VOLATILE3
) {
1002 parse_asm_str(&astr
);
1006 memset(clobber_regs
, 0, sizeof(clobber_regs
));
1011 parse_asm_operands(operands
, &nb_operands
, 1);
1012 nb_outputs
= nb_operands
;
1017 parse_asm_operands(operands
, &nb_operands
, 0);
1020 /* XXX: handle registers */
1024 expect("string constant");
1025 asm_clobber(clobber_regs
, tokc
.cstr
->data
);
1038 /* NOTE: we do not eat the ';' so that we can restore the current
1039 token after the assembler parsing */
1042 nb_inputs
= nb_operands
- nb_outputs
;
1044 /* save all values in the memory */
1047 /* compute constraints */
1048 asm_compute_constraints(operands
, nb_operands
, nb_outputs
,
1049 clobber_regs
, &out_reg
);
1051 /* substitute the operands in the asm string. No substitution is
1052 done if no operands (GCC behaviour) */
1054 printf("asm: \"%s\"\n", (char *)astr
.data
);
1057 subst_asm_operands(operands
, nb_operands
, nb_outputs
, &astr1
, &astr
);
1063 printf("subst_asm: \"%s\"\n", (char *)astr1
.data
);
1066 /* generate loads */
1067 asm_gen_code(operands
, nb_operands
, nb_outputs
, 0,
1068 clobber_regs
, out_reg
);
1070 /* assemble the string with tcc internal assembler */
1071 tcc_assemble_inline(tcc_state
, astr1
.data
, astr1
.size
- 1);
1073 /* restore the current C token */
1076 /* store the output values if needed */
1077 asm_gen_code(operands
, nb_operands
, nb_outputs
, 1,
1078 clobber_regs
, out_reg
);
1080 /* free everything */
1081 for(i
=0;i
<nb_operands
;i
++) {
1084 tcc_free(op
->constraint
);
1090 ST_FUNC
void asm_global_instr(void)
1095 parse_asm_str(&astr
);
1097 /* NOTE: we do not eat the ';' so that we can restore the current
1098 token after the assembler parsing */
1103 printf("asm_global: \"%s\"\n", (char *)astr
.data
);
1105 cur_text_section
= text_section
;
1106 ind
= cur_text_section
->data_offset
;
1108 /* assemble the string with tcc internal assembler */
1109 tcc_assemble_inline(tcc_state
, astr
.data
, astr
.size
- 1);
1111 cur_text_section
->data_offset
= ind
;
1113 /* restore the current C token */