1 /* This is the Assembler Pre-Processor
2 Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 96, 97, 98, 1999
3 Free Software Foundation, Inc.
5 This file is part of GAS, the GNU Assembler.
7 GAS is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GAS is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GAS; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
22 /* Modified by Allen Wirfs-Brock, Instantiations Inc 2/90 */
23 /* App, the assembler pre-processor. This pre-processor strips out excess
24 spaces, turns single-quoted characters into a decimal constant, and turns
25 # <number> <filename> <garbage> into a .line <number>\n.file <filename>
26 pair. This needs better error-handling. */
29 #include "as.h" /* For BAD_CASE() only */
33 #define const /* empty */
37 /* Whether we are scrubbing in m68k MRI mode. This is different from
38 flag_m68k_mri, because the two flags will be affected by the .mri
39 pseudo-op at different times. */
40 static int scrub_m68k_mri
;
42 /* The pseudo-op which switches in and out of MRI mode. See the
43 comment in do_scrub_chars. */
44 static const char mri_pseudo
[] = ".mri 0";
46 #if defined TC_ARM && defined OBJ_ELF
47 /* The pseudo-op for which we need to special-case `@' characters.
48 See the comment in do_scrub_chars. */
49 static const char symver_pseudo
[] = ".symver";
50 static const char * symver_state
;
54 static const char symbol_chars
[] =
55 "$._ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789";
57 #define LEX_IS_SYMBOL_COMPONENT 1
58 #define LEX_IS_WHITESPACE 2
59 #define LEX_IS_LINE_SEPARATOR 3
60 #define LEX_IS_COMMENT_START 4
61 #define LEX_IS_LINE_COMMENT_START 5
62 #define LEX_IS_TWOCHAR_COMMENT_1ST 6
63 #define LEX_IS_STRINGQUOTE 8
64 #define LEX_IS_COLON 9
65 #define LEX_IS_NEWLINE 10
66 #define LEX_IS_ONECHAR_QUOTE 11
68 #define LEX_IS_DOUBLEDASH_1ST 12
71 #define LEX_IS_DOUBLEBAR_1ST 13
73 #define IS_SYMBOL_COMPONENT(c) (lex[c] == LEX_IS_SYMBOL_COMPONENT)
74 #define IS_WHITESPACE(c) (lex[c] == LEX_IS_WHITESPACE)
75 #define IS_LINE_SEPARATOR(c) (lex[c] == LEX_IS_LINE_SEPARATOR)
76 #define IS_COMMENT(c) (lex[c] == LEX_IS_COMMENT_START)
77 #define IS_LINE_COMMENT(c) (lex[c] == LEX_IS_LINE_COMMENT_START)
78 #define IS_NEWLINE(c) (lex[c] == LEX_IS_NEWLINE)
80 static int process_escape
PARAMS ((int));
82 /* FIXME-soon: The entire lexer/parser thingy should be
83 built statically at compile time rather than dynamically
84 each and every time the assembler is run. xoxorich. */
87 do_scrub_begin (m68k_mri
)
93 scrub_m68k_mri
= m68k_mri
;
95 lex
[' '] = LEX_IS_WHITESPACE
;
96 lex
['\t'] = LEX_IS_WHITESPACE
;
97 lex
['\r'] = LEX_IS_WHITESPACE
;
98 lex
['\n'] = LEX_IS_NEWLINE
;
99 lex
[';'] = LEX_IS_LINE_SEPARATOR
;
100 lex
[':'] = LEX_IS_COLON
;
104 lex
['"'] = LEX_IS_STRINGQUOTE
;
107 lex
['\''] = LEX_IS_ONECHAR_QUOTE
;
110 #ifdef SINGLE_QUOTE_STRINGS
111 lex
['\''] = LEX_IS_STRINGQUOTE
;
115 /* Note: if any other character can be LEX_IS_STRINGQUOTE, the loop
116 in state 5 of do_scrub_chars must be changed. */
118 /* Note that these override the previous defaults, e.g. if ';' is a
119 comment char, then it isn't a line separator. */
120 for (p
= symbol_chars
; *p
; ++p
)
122 lex
[(unsigned char) *p
] = LEX_IS_SYMBOL_COMPONENT
;
123 } /* declare symbol characters */
125 for (c
= 128; c
< 256; ++c
)
126 lex
[c
] = LEX_IS_SYMBOL_COMPONENT
;
128 #ifdef tc_symbol_chars
129 /* This macro permits the processor to specify all characters which
130 may appears in an operand. This will prevent the scrubber from
131 discarding meaningful whitespace in certain cases. The i386
132 backend uses this to support prefixes, which can confuse the
133 scrubber as to whether it is parsing operands or opcodes. */
134 for (p
= tc_symbol_chars
; *p
; ++p
)
135 lex
[(unsigned char) *p
] = LEX_IS_SYMBOL_COMPONENT
;
138 /* The m68k backend wants to be able to change comment_chars. */
139 #ifndef tc_comment_chars
140 #define tc_comment_chars comment_chars
142 for (p
= tc_comment_chars
; *p
; p
++)
144 lex
[(unsigned char) *p
] = LEX_IS_COMMENT_START
;
145 } /* declare comment chars */
147 for (p
= line_comment_chars
; *p
; p
++)
149 lex
[(unsigned char) *p
] = LEX_IS_LINE_COMMENT_START
;
150 } /* declare line comment chars */
152 for (p
= line_separator_chars
; *p
; p
++)
154 lex
[(unsigned char) *p
] = LEX_IS_LINE_SEPARATOR
;
155 } /* declare line separators */
157 /* Only allow slash-star comments if slash is not in use.
158 FIXME: This isn't right. We should always permit them. */
161 lex
['/'] = LEX_IS_TWOCHAR_COMMENT_1ST
;
166 lex
['\''] = LEX_IS_STRINGQUOTE
;
167 lex
[';'] = LEX_IS_COMMENT_START
;
168 lex
['*'] = LEX_IS_LINE_COMMENT_START
;
169 /* The MRI documentation says '!' is LEX_IS_COMMENT_START, but
170 then it can't be used in an expression. */
171 lex
['!'] = LEX_IS_LINE_COMMENT_START
;
175 lex
['-'] = LEX_IS_DOUBLEDASH_1ST
;
178 lex
['|'] = LEX_IS_DOUBLEBAR_1ST
;
181 /* must do this is we want VLIW instruction with "->" or "<-" */
182 lex
['-'] = LEX_IS_SYMBOL_COMPONENT
;
184 } /* do_scrub_begin() */
186 /* Saved state of the scrubber */
188 static int old_state
;
189 static char *out_string
;
190 static char out_buf
[20];
191 static int add_newlines
;
192 static char *saved_input
;
193 static int saved_input_len
;
194 static const char *mri_state
;
195 static char mri_last_ch
;
197 /* Data structure for saving the state of app across #include's. Note that
198 app is called asynchronously to the parsing of the .include's, so our
199 state at the time .include is interpreted is completely unrelated.
200 That's why we have to save it all. */
207 char out_buf
[sizeof (out_buf
)];
212 const char * mri_state
;
214 #if defined TC_ARM && defined OBJ_ELF
215 const char * symver_state
;
222 register struct app_save
*saved
;
224 saved
= (struct app_save
*) xmalloc (sizeof (*saved
));
225 saved
->state
= state
;
226 saved
->old_state
= old_state
;
227 saved
->out_string
= out_string
;
228 memcpy (saved
->out_buf
, out_buf
, sizeof (out_buf
));
229 saved
->add_newlines
= add_newlines
;
230 saved
->saved_input
= saved_input
;
231 saved
->saved_input_len
= saved_input_len
;
232 saved
->scrub_m68k_mri
= scrub_m68k_mri
;
233 saved
->mri_state
= mri_state
;
234 saved
->mri_last_ch
= mri_last_ch
;
235 #if defined TC_ARM && defined OBJ_ELF
236 saved
->symver_state
= symver_state
;
239 /* do_scrub_begin() is not useful, just wastes time. */
244 return (char *) saved
;
251 register struct app_save
*saved
= (struct app_save
*) arg
;
253 /* There is no do_scrub_end (). */
254 state
= saved
->state
;
255 old_state
= saved
->old_state
;
256 out_string
= saved
->out_string
;
257 memcpy (out_buf
, saved
->out_buf
, sizeof (out_buf
));
258 add_newlines
= saved
->add_newlines
;
259 saved_input
= saved
->saved_input
;
260 saved_input_len
= saved
->saved_input_len
;
261 scrub_m68k_mri
= saved
->scrub_m68k_mri
;
262 mri_state
= saved
->mri_state
;
263 mri_last_ch
= saved
->mri_last_ch
;
264 #if defined TC_ARM && defined OBJ_ELF
265 symver_state
= saved
->symver_state
;
271 /* @@ This assumes that \n &c are the same on host and target. This is not
298 /* This function is called to process input characters. The GET
299 parameter is used to retrieve more input characters. GET should
300 set its parameter to point to a buffer, and return the length of
301 the buffer; it should return 0 at end of file. The scrubbed output
302 characters are put into the buffer starting at TOSTART; the TOSTART
303 buffer is TOLEN bytes in length. The function returns the number
304 of scrubbed characters put into TOSTART. This will be TOLEN unless
305 end of file was seen. This function is arranged as a state
306 machine, and saves its state so that it may return at any point.
307 This is the way the old code used to work. */
310 do_scrub_chars (get
, tostart
, tolen
)
311 int (*get
) PARAMS ((char **));
316 char *toend
= tostart
+ tolen
;
320 register int ch
, ch2
= 0;
322 /*State 0: beginning of normal line
323 1: After first whitespace on line (flush more white)
324 2: After first non-white (opcode) on line (keep 1white)
325 3: after second white on line (into operands) (flush white)
326 4: after putting out a .line, put out digits
327 5: parsing a string, then go to old-state
328 6: putting out \ escape in a "d string.
329 7: After putting out a .appfile, put out string.
330 8: After putting out a .appfile string, flush until newline.
331 9: After seeing symbol char in state 3 (keep 1white after symchar)
332 10: After seeing whitespace in state 9 (keep white before symchar)
333 11: After seeing a symbol character in state 0 (eg a label definition)
334 -1: output string in out_string and go to the state in old_state
335 -2: flush text until a '*' '/' is seen, then go to state old_state
337 12: After seeing a dash, looking for a second dash as a start of comment.
340 13: After seeing a vertical bar, looking for a second vertical bar as a parallel expression seperator.
344 /* I added states 9 and 10 because the MIPS ECOFF assembler uses
345 constructs like ``.loc 1 20''. This was turning into ``.loc
346 120''. States 9 and 10 ensure that a space is never dropped in
347 between characters which could appear in a identifier. Ian
348 Taylor, ian@cygnus.com.
350 I added state 11 so that something like "Lfoo add %r25,%r26,%r27" works
351 correctly on the PA (and any other target where colons are optional).
352 Jeff Law, law@cs.utah.edu.
354 I added state 13 so that something like "cmp r1, r2 || trap #1" does not
355 get squashed into "cmp r1,r2||trap#1", with the all important space
356 between the 'trap' and the '#1' being eliminated. nickc@cygnus.com */
358 /* This macro gets the next input character. */
362 ? * (unsigned char *) (from++) \
363 : ((saved_input != NULL \
364 ? (free (saved_input), \
365 saved_input = NULL, \
368 fromlen = (*get) (&from), \
369 fromend = from + fromlen, \
372 : * (unsigned char *) (from++))))
374 /* This macro pushes a character back on the input stream. */
376 #define UNGET(uch) (*--from = (uch))
378 /* This macro puts a character into the output buffer. If this
379 character fills the output buffer, this macro jumps to the label
380 TOFULL. We use this rather ugly approach because we need to
381 handle two different termination conditions: EOF on the input
382 stream, and a full output buffer. It would be simpler if we
383 always read in the entire input stream before processing it, but
384 I don't want to make such a significant change to the assembler's
396 if (saved_input
!= NULL
)
399 fromend
= from
+ saved_input_len
;
403 fromlen
= (*get
) (&from
);
406 fromend
= from
+ fromlen
;
411 /* The cases in this switch end with continue, in order to
412 branch back to the top of this while loop and generate the
413 next output character in the appropriate state. */
418 if (*out_string
== '\0')
435 as_warn (_("end of file in comment"));
444 while ((ch
= GET ()) == '*')
449 as_warn (_("end of file in comment"));
467 else if (ch
>= '0' && ch
<= '9')
471 while (ch
!= EOF
&& IS_WHITESPACE (ch
))
477 out_string
= "\n\tappfile ";
479 out_string
= "\n\t.appfile ";
486 while (ch
!= EOF
&& ch
!= '\n')
495 /* We are going to copy everything up to a quote character,
496 with special handling for a backslash. We try to
497 optimize the copying in the simple case without using the
498 GET and PUT macros. */
503 for (s
= from
; s
< fromend
; s
++)
506 /* This condition must be changed if the type of any
507 other character can be LEX_IS_STRINGQUOTE. */
515 if (len
> toend
- to
)
519 memcpy (to
, from
, len
);
528 as_warn (_("end of file in string: inserted '\"'"));
533 else if (lex
[ch
] == LEX_IS_STRINGQUOTE
)
538 #ifndef NO_STRING_ESCAPES
545 else if (scrub_m68k_mri
&& ch
== '\n')
547 /* Just quietly terminate the string. This permits lines like
548 bne label loop if we haven't reach end yet
565 /* Handle strings broken across lines, by turning '\n' into
592 #if defined(IGNORE_NONSTANDARD_ESCAPES) | defined(ONLY_STANDARD_ESCAPES)
594 as_warn (_("Unknown escape '\\%c' in string: Ignored"), ch
);
596 #else /* ONLY_STANDARD_ESCAPES */
598 /* Accept \x as x for any x */
600 #endif /* ONLY_STANDARD_ESCAPES */
603 as_warn (_("End of file in string: '\"' inserted"));
622 while (ch
!= '\n' && ch
!= EOF
);
630 /* OK, we are somewhere in states 0 through 4 or 9 through 11 */
637 #if defined TC_ARM && defined OBJ_ELF
638 /* We need to watch out for .symver directives. See the comment later
640 if (symver_state
== NULL
)
642 if ((state
== 0 || state
== 1) && ch
== symver_pseudo
[0])
643 symver_state
= symver_pseudo
+ 1;
647 /* We advance to the next state if we find the right
649 if (ch
!= '\0' && (*symver_state
== ch
))
651 else if (*symver_state
!= '\0')
652 /* We did not get the expected character, or we didn't
653 get a valid terminating character after seeing the
654 entire pseudo-op, so we must go back to the beginning. */
658 /* We've read the entire pseudo-op. If this is the end
659 of the line, go back to the beginning. */
664 #endif /* TC_ARM && OBJ_ELF */
667 /* We want to have pseudo-ops which control whether we are in
668 MRI mode or not. Unfortunately, since m68k MRI mode affects
669 the scrubber, that means that we need a special purpose
671 if (mri_state
== NULL
)
673 if ((state
== 0 || state
== 1)
674 && ch
== mri_pseudo
[0])
675 mri_state
= mri_pseudo
+ 1;
679 /* We advance to the next state if we find the right
680 character, or if we need a space character and we get any
681 whitespace character, or if we need a '0' and we get a
682 '1' (this is so that we only need one state to handle
683 ``.mri 0'' and ``.mri 1''). */
686 || (*mri_state
== ' '
687 && lex
[ch
] == LEX_IS_WHITESPACE
)
688 || (*mri_state
== '0'
694 else if (*mri_state
!= '\0'
695 || (lex
[ch
] != LEX_IS_WHITESPACE
696 && lex
[ch
] != LEX_IS_NEWLINE
))
698 /* We did not get the expected character, or we didn't
699 get a valid terminating character after seeing the
700 entire pseudo-op, so we must go back to the
706 /* We've read the entire pseudo-op. mips_last_ch is
707 either '0' or '1' indicating whether to enter or
709 do_scrub_begin (mri_last_ch
== '1');
712 /* We continue handling the character as usual. The
713 main gas reader must also handle the .mri pseudo-op
714 to control expression parsing and the like. */
723 as_warn (_("end of file not at end of a line; newline inserted"));
732 case LEX_IS_WHITESPACE
:
737 while (ch
!= EOF
&& IS_WHITESPACE (ch
));
743 /* Preserve a single whitespace character at the
744 beginning of a line. */
753 || IS_LINE_SEPARATOR (ch
))
757 /* In MRI mode, we keep these spaces. */
765 /* If we're in state 2 or 11, we've seen a non-white
766 character followed by whitespace. If the next character
767 is ':', this is whitespace after a label name which we
768 normally must ignore. In MRI mode, though, spaces are
769 not permitted between the label and the colon. */
770 if ((state
== 2 || state
== 11)
771 && lex
[ch
] == LEX_IS_COLON
783 goto recycle
; /* Punted leading sp */
785 /* We can arrive here if we leave a leading whitespace
786 character at the beginning of a line. */
792 /* Optimize common case by skipping UNGET/GET. */
793 PUT (' '); /* Sp after opco */
802 /* In MRI mode, we keep these spaces. */
807 goto recycle
; /* Sp in operands */
812 /* In MRI mode, we keep these spaces. */
818 state
= 10; /* Sp after symbol char */
822 #ifdef LABELS_WITHOUT_COLONS
829 /* We know that ch is not ':', since we tested that
830 case above. Therefore this is not a label, so it
831 must be the opcode, and we've just seen the
832 whitespace after it. */
836 PUT (' '); /* Sp after label definition. */
843 case LEX_IS_TWOCHAR_COMMENT_1ST
:
852 if (ch2
!= EOF
&& IS_NEWLINE (ch2
))
855 while (ch2
!= EOF
&& ch2
!= '*');
860 if (ch2
== EOF
|| ch2
== '/')
863 /* This UNGET will ensure that we count newlines
869 as_warn (_("end of file in multiline comment"));
878 if (state
== 9 || state
== 10)
884 case LEX_IS_STRINGQUOTE
:
887 /* Preserve the whitespace in foo "bar" */
892 /* PUT didn't jump out. We could just break, but we
893 know what will happen, so optimize a bit. */
906 case LEX_IS_ONECHAR_QUOTE
:
909 /* Preserve the whitespace in foo 'b' */
918 as_warn (_("end of file after a one-character quote; \\0 inserted"));
926 as_warn (_("end of file in escape character"));
930 ch
= process_escape (ch
);
932 sprintf (out_buf
, "%d", (int) (unsigned char) ch
);
934 /* None of these 'x constants for us. We want 'x'. */
935 if ((ch
= GET ()) != '\'')
937 #ifdef REQUIRE_CHAR_CLOSE_QUOTE
938 as_warn (_("Missing close quote: (assumed)"));
944 if (strlen (out_buf
) == 1)
954 out_string
= out_buf
;
960 if (state
== 9 || state
== 10)
968 /* Roll out a bunch of newlines from inside comments, etc. */
974 /* fall thru into... */
976 case LEX_IS_LINE_SEPARATOR
:
982 case LEX_IS_DOUBLEDASH_1ST
:
989 /* read and skip to end of line */
994 while (ch
!= EOF
&& ch
!= '\n');
997 as_warn (_("end of file in comment; newline inserted"));
1004 case LEX_IS_DOUBLEBAR_1ST
:
1011 /* Reset back to state 1 and pretend that we are parsing a line from
1012 just after the first white space. */
1018 case LEX_IS_LINE_COMMENT_START
:
1019 /* FIXME-someday: The two character comment stuff was badly
1020 thought out. On i386, we want '/' as line comment start
1021 AND we want C style comments. hence this hack. The
1022 whole lexical process should be reworked. xoxorich. */
1038 if (state
== 0 || state
== 1) /* Only comment at start of line. */
1048 while (ch
!= EOF
&& IS_WHITESPACE (ch
));
1051 as_warn (_("end of file in comment; newline inserted"));
1055 if (ch
< '0' || ch
> '9' || state
!= 0 || startch
!= '#')
1057 /* Not a cpp line. */
1058 while (ch
!= EOF
&& !IS_NEWLINE (ch
))
1061 as_warn (_("EOF in Comment: Newline inserted"));
1066 /* Loks like `# 123 "filename"' from cpp. */
1071 out_string
= "\tappline ";
1073 out_string
= "\t.appline ";
1074 PUT (*out_string
++);
1079 /* All insns end in a char for which LEX_IS_SYMBOL_COMPONENT is true.
1080 Trap is the only short insn that has a first operand that is
1081 neither register nor label.
1082 We must prevent exef0f ||trap #1 to degenerate to exef0f ||trap#1 .
1083 We can't make '#' LEX_IS_SYMBOL_COMPONENT because it is already
1084 LEX_IS_LINE_COMMENT_START. However, it is the only character in
1085 line_comment_chars for d10v, hence we can recognize it as such. */
1086 /* An alternative approach would be to reset the state to 1 when
1087 we see '||', '<'- or '->', but that seems to be overkill. */
1088 if (state
== 10) PUT (' ');
1090 /* We have a line comment character which is not at the
1091 start of a line. If this is also a normal comment
1092 character, fall through. Otherwise treat it as a default
1094 if (strchr (tc_comment_chars
, ch
) == NULL
1095 && (! scrub_m68k_mri
1096 || (ch
!= '!' && ch
!= '*')))
1099 && (ch
== '!' || ch
== '*' || ch
== '#')
1104 case LEX_IS_COMMENT_START
:
1105 #if defined TC_ARM && defined OBJ_ELF
1106 /* On the ARM, `@' is the comment character.
1107 Unfortunately this is also a special character in ELF .symver
1108 directives (and .type, though we deal with those another way). So
1109 we check if this line is such a directive, and treat the character
1110 as default if so. This is a hack. */
1111 if ((symver_state
!= NULL
) && (*symver_state
== 0))
1118 while (ch
!= EOF
&& !IS_NEWLINE (ch
));
1120 as_warn (_("end of file in comment; newline inserted"));
1125 case LEX_IS_SYMBOL_COMPONENT
:
1128 /* This is a symbol character following another symbol
1129 character, with whitespace in between. We skipped
1130 the whitespace earlier, so output it now. */
1140 /* This is a common case. Quickly copy CH and all the
1141 following symbol component or normal characters. */
1143 && mri_state
== NULL
1144 #if defined TC_ARM && defined OBJ_ELF
1145 && symver_state
== NULL
1152 for (s
= from
; s
< fromend
; s
++)
1156 ch2
= * (unsigned char *) s
;
1159 && type
!= LEX_IS_SYMBOL_COMPONENT
)
1164 /* Handle the last character normally, for
1169 if (len
> (toend
- to
) - 1)
1170 len
= (toend
- to
) - 1;
1176 memcpy (to
, from
, len
);
1184 case 8: *to
++ = *from
++;
1185 case 7: *to
++ = *from
++;
1186 case 6: *to
++ = *from
++;
1187 case 5: *to
++ = *from
++;
1188 case 4: *to
++ = *from
++;
1189 case 3: *to
++ = *from
++;
1190 case 2: *to
++ = *from
++;
1191 case 1: *to
++ = *from
++;
1201 /* Some relatively `normal' character. */
1204 state
= 11; /* Now seeing label definition */
1206 else if (state
== 1)
1208 state
= 2; /* Ditto */
1210 else if (state
== 9)
1212 if (lex
[ch
] != LEX_IS_SYMBOL_COMPONENT
)
1215 else if (state
== 10)
1227 /* We have reached the end of the input. */
1228 return to
- tostart
;
1231 /* The output buffer is full. Save any input we have not yet
1237 save
= (char *) xmalloc (fromend
- from
);
1238 memcpy (save
, from
, fromend
- from
);
1239 if (saved_input
!= NULL
)
1242 saved_input_len
= fromend
- from
;
1246 if (saved_input
!= NULL
)
1252 return to
- tostart
;