/* This is the Assembler Pre-Processor Copyright (C) 1987, 90, 91, 92, 93, 94, 95, 1996 Free Software Foundation, Inc. This file is part of GAS, the GNU Assembler. GAS is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GAS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GAS; see the file COPYING. If not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /* Modified by Allen Wirfs-Brock, Instantiations Inc 2/90 */ /* App, the assembler pre-processor. This pre-processor strips out excess spaces, turns single-quoted characters into a decimal constant, and turns # into a .line \n.file pair. This needs better error-handling. */ #include #include "as.h" /* For BAD_CASE() only */ #if (__STDC__ != 1) #ifndef const #define const /* empty */ #endif #endif /* Whether we are scrubbing in m68k MRI mode. This is different from flag_m68k_mri, because the two flags will be affected by the .mri pseudo-op at different times. */ static int scrub_m68k_mri; /* The pseudo-op which switches in and out of MRI mode. See the comment in do_scrub_chars. */ static const char mri_pseudo[] = ".mri 0"; static char lex[256]; static const char symbol_chars[] = "$._ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"; #define LEX_IS_SYMBOL_COMPONENT 1 #define LEX_IS_WHITESPACE 2 #define LEX_IS_LINE_SEPARATOR 3 #define LEX_IS_COMMENT_START 4 #define LEX_IS_LINE_COMMENT_START 5 #define LEX_IS_TWOCHAR_COMMENT_1ST 6 #define LEX_IS_TWOCHAR_COMMENT_2ND 7 #define LEX_IS_STRINGQUOTE 8 #define LEX_IS_COLON 9 #define LEX_IS_NEWLINE 10 #define LEX_IS_ONECHAR_QUOTE 11 #define IS_SYMBOL_COMPONENT(c) (lex[c] == LEX_IS_SYMBOL_COMPONENT) #define IS_WHITESPACE(c) (lex[c] == LEX_IS_WHITESPACE) #define IS_LINE_SEPARATOR(c) (lex[c] == LEX_IS_LINE_SEPARATOR) #define IS_COMMENT(c) (lex[c] == LEX_IS_COMMENT_START) #define IS_LINE_COMMENT(c) (lex[c] == LEX_IS_LINE_COMMENT_START) #define IS_NEWLINE(c) (lex[c] == LEX_IS_NEWLINE) static int process_escape PARAMS ((int)); /* FIXME-soon: The entire lexer/parser thingy should be built statically at compile time rather than dynamically each and every time the assembler is run. xoxorich. */ void do_scrub_begin (m68k_mri) int m68k_mri; { const char *p; scrub_m68k_mri = m68k_mri; lex[' '] = LEX_IS_WHITESPACE; lex['\t'] = LEX_IS_WHITESPACE; lex['\n'] = LEX_IS_NEWLINE; lex[';'] = LEX_IS_LINE_SEPARATOR; lex[':'] = LEX_IS_COLON; if (! m68k_mri) { lex['"'] = LEX_IS_STRINGQUOTE; #ifndef TC_HPPA lex['\''] = LEX_IS_ONECHAR_QUOTE; #endif #ifdef SINGLE_QUOTE_STRINGS lex['\''] = LEX_IS_STRINGQUOTE; #endif } /* Note: if any other character can be LEX_IS_STRINGQUOTE, the loop in state 5 of do_scrub_chars must be changed. */ /* Note that these override the previous defaults, e.g. if ';' is a comment char, then it isn't a line separator. */ for (p = symbol_chars; *p; ++p) { lex[(unsigned char) *p] = LEX_IS_SYMBOL_COMPONENT; } /* declare symbol characters */ /* The m68k backend wants to be able to change comment_chars. */ #ifndef tc_comment_chars #define tc_comment_chars comment_chars #endif for (p = tc_comment_chars; *p; p++) { lex[(unsigned char) *p] = LEX_IS_COMMENT_START; } /* declare comment chars */ for (p = line_comment_chars; *p; p++) { lex[(unsigned char) *p] = LEX_IS_LINE_COMMENT_START; } /* declare line comment chars */ for (p = line_separator_chars; *p; p++) { lex[(unsigned char) *p] = LEX_IS_LINE_SEPARATOR; } /* declare line separators */ /* Only allow slash-star comments if slash is not in use */ if (lex['/'] == 0) { lex['/'] = LEX_IS_TWOCHAR_COMMENT_1ST; } /* FIXME-soon. This is a bad hack but otherwise, we can't do c-style comments when '/' is a line comment char. xoxorich. */ if (lex['*'] == 0) { lex['*'] = LEX_IS_TWOCHAR_COMMENT_2ND; } if (m68k_mri) { lex['\''] = LEX_IS_STRINGQUOTE; lex[';'] = LEX_IS_COMMENT_START; lex['*'] = LEX_IS_LINE_COMMENT_START; /* The MRI documentation says '!' is LEX_IS_COMMENT_START, but then it can't be used in an expression. */ lex['!'] = LEX_IS_LINE_COMMENT_START; } } /* do_scrub_begin() */ /* Saved state of the scrubber */ static int state; static int old_state; static char *out_string; static char out_buf[20]; static int add_newlines; static char *saved_input; static int saved_input_len; static const char *mri_state; static char mri_last_ch; /* Data structure for saving the state of app across #include's. Note that app is called asynchronously to the parsing of the .include's, so our state at the time .include is interpreted is completely unrelated. That's why we have to save it all. */ struct app_save { int state; int old_state; char *out_string; char out_buf[sizeof (out_buf)]; int add_newlines; char *saved_input; int saved_input_len; int scrub_m68k_mri; const char *mri_state; char mri_last_ch; }; char * app_push () { register struct app_save *saved; saved = (struct app_save *) xmalloc (sizeof (*saved)); saved->state = state; saved->old_state = old_state; saved->out_string = out_string; memcpy (saved->out_buf, out_buf, sizeof (out_buf)); saved->add_newlines = add_newlines; saved->saved_input = saved_input; saved->saved_input_len = saved_input_len; saved->scrub_m68k_mri = scrub_m68k_mri; saved->mri_state = mri_state; saved->mri_last_ch = mri_last_ch; /* do_scrub_begin() is not useful, just wastes time. */ state = 0; saved_input = NULL; return (char *) saved; } void app_pop (arg) char *arg; { register struct app_save *saved = (struct app_save *) arg; /* There is no do_scrub_end (). */ state = saved->state; old_state = saved->old_state; out_string = saved->out_string; memcpy (out_buf, saved->out_buf, sizeof (out_buf)); add_newlines = saved->add_newlines; saved_input = saved->saved_input; saved_input_len = saved->saved_input_len; scrub_m68k_mri = saved->scrub_m68k_mri; mri_state = saved->mri_state; mri_last_ch = saved->mri_last_ch; free (arg); } /* app_pop() */ /* @@ This assumes that \n &c are the same on host and target. This is not necessarily true. */ static int process_escape (ch) int ch; { switch (ch) { case 'b': return '\b'; case 'f': return '\f'; case 'n': return '\n'; case 'r': return '\r'; case 't': return '\t'; case '\'': return '\''; case '"': return '\"'; default: return ch; } } /* This function is called to process input characters. The GET parameter is used to retrieve more input characters. GET should set its parameter to point to a buffer, and return the length of the buffer; it should return 0 at end of file. The scrubbed output characters are put into the buffer starting at TOSTART; the TOSTART buffer is TOLEN bytes in length. The function returns the number of scrubbed characters put into TOSTART. This will be TOLEN unless end of file was seen. This function is arranged as a state machine, and saves its state so that it may return at any point. This is the way the old code used to work. */ int do_scrub_chars (get, tostart, tolen) int (*get) PARAMS ((char **)); char *tostart; int tolen; { char *to = tostart; char *toend = tostart + tolen; char *from; char *fromend; int fromlen; register int ch, ch2 = 0; /*State 0: beginning of normal line 1: After first whitespace on line (flush more white) 2: After first non-white (opcode) on line (keep 1white) 3: after second white on line (into operands) (flush white) 4: after putting out a .line, put out digits 5: parsing a string, then go to old-state 6: putting out \ escape in a "d string. 7: After putting out a .appfile, put out string. 8: After putting out a .appfile string, flush until newline. 9: After seeing symbol char in state 3 (keep 1white after symchar) 10: After seeing whitespace in state 9 (keep white before symchar) 11: After seeing a symbol character in state 0 (eg a label definition) -1: output string in out_string and go to the state in old_state -2: flush text until a '*' '/' is seen, then go to state old_state */ /* I added states 9 and 10 because the MIPS ECOFF assembler uses constructs like ``.loc 1 20''. This was turning into ``.loc 120''. States 9 and 10 ensure that a space is never dropped in between characters which could appear in a identifier. Ian Taylor, ian@cygnus.com. I added state 11 so that something like "Lfoo add %r25,%r26,%r27" works correctly on the PA (and any other target where colons are optional). Jeff Law, law@cs.utah.edu. */ /* This macro gets the next input character. */ #define GET() \ (from < fromend \ ? *from++ \ : ((saved_input != NULL \ ? (free (saved_input), \ saved_input = NULL, \ 0) \ : 0), \ fromlen = (*get) (&from), \ fromend = from + fromlen, \ (fromlen == 0 \ ? EOF \ : *from++))) /* This macro pushes a character back on the input stream. */ #define UNGET(uch) (*--from = (uch)) /* This macro puts a character into the output buffer. If this character fills the output buffer, this macro jumps to the label TOFULL. We use this rather ugly approach because we need to handle two different termination conditions: EOF on the input stream, and a full output buffer. It would be simpler if we always read in the entire input stream before processing it, but I don't want to make such a significant change to the assembler's memory usage. */ #define PUT(pch) \ do \ { \ *to++ = (pch); \ if (to >= toend) \ goto tofull; \ } \ while (0) if (saved_input != NULL) { from = saved_input; fromend = from + saved_input_len; } else { fromlen = (*get) (&from); if (fromlen == 0) return 0; fromend = from + fromlen; } while (1) { /* The cases in this switch end with continue, in order to branch back to the top of this while loop and generate the next output character in the appropriate state. */ switch (state) { case -1: ch = *out_string++; if (*out_string == '\0') { state = old_state; old_state = 3; } PUT (ch); continue; case -2: for (;;) { do { ch = GET (); if (ch == EOF) { as_warn ("end of file in comment"); goto fromeof; } if (ch == '\n') PUT ('\n'); } while (ch != '*'); while ((ch = GET ()) == '*') ; if (ch == EOF) { as_warn ("end of file in comment"); goto fromeof; } if (ch == '/') break; UNGET (ch); } state = old_state; PUT (' '); continue; case 4: ch = GET (); if (ch == EOF) goto fromeof; else if (ch >= '0' && ch <= '9') PUT (ch); else { while (ch != EOF && IS_WHITESPACE (ch)) ch = GET (); if (ch == '"') { UNGET (ch); if (scrub_m68k_mri) out_string = "\n\tappfile "; else out_string = "\n\t.appfile "; old_state = 7; state = -1; PUT (*out_string++); } else { while (ch != EOF && ch != '\n') ch = GET (); state = 0; PUT (ch); } } continue; case 5: /* We are going to copy everything up to a quote character, with special handling for a backslash. We try to optimize the copying in the simple case without using the GET and PUT macros. */ { char *s; int len; for (s = from; s < fromend; s++) { ch = *s; /* This condition must be changed if the type of any other character can be LEX_IS_STRINGQUOTE. */ if (ch == '\\' || ch == '"' || ch == '\'' || ch == '\n') break; } len = s - from; if (len > toend - to) len = toend - to; if (len > 0) { memcpy (to, from, len); to += len; from += len; } } ch = GET (); if (ch == EOF) { as_warn ("end of file in string: inserted '\"'"); state = old_state; UNGET ('\n'); PUT ('"'); } else if (lex[ch] == LEX_IS_STRINGQUOTE) { state = old_state; PUT (ch); } #ifndef NO_STRING_ESCAPES else if (ch == '\\') { state = 6; PUT (ch); } #endif else if (scrub_m68k_mri && ch == '\n') { /* Just quietly terminate the string. This permits lines like bne label loop if we haven't reach end yet */ state = old_state; UNGET (ch); PUT ('\''); } else { PUT (ch); } continue; case 6: state = 5; ch = GET (); switch (ch) { /* Handle strings broken across lines, by turning '\n' into '\\' and 'n'. */ case '\n': UNGET ('n'); add_newlines++; PUT ('\\'); continue; case '"': case '\\': case 'b': case 'f': case 'n': case 'r': case 't': case 'v': case 'x': case 'X': case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': break; #if defined(IGNORE_NONSTANDARD_ESCAPES) | defined(ONLY_STANDARD_ESCAPES) default: as_warn ("Unknown escape '\\%c' in string: Ignored", ch); break; #else /* ONLY_STANDARD_ESCAPES */ default: /* Accept \x as x for any x */ break; #endif /* ONLY_STANDARD_ESCAPES */ case EOF: as_warn ("End of file in string: '\"' inserted"); PUT ('"'); continue; } PUT (ch); continue; case 7: ch = GET (); state = 5; old_state = 8; if (ch == EOF) goto fromeof; PUT (ch); continue; case 8: do ch = GET (); while (ch != '\n' && ch != EOF); if (ch == EOF) goto fromeof; state = 0; PUT (ch); continue; } /* OK, we are somewhere in states 0 through 4 or 9 through 11 */ /* flushchar: */ ch = GET (); recycle: #ifdef TC_M68K /* We want to have pseudo-ops which control whether we are in MRI mode or not. Unfortunately, since m68k MRI mode affects the scrubber, that means that we need a special purpose recognizer here. */ if (mri_state == NULL) { if ((state == 0 || state == 1) && ch == mri_pseudo[0]) mri_state = mri_pseudo + 1; } else { /* We advance to the next state if we find the right character, or if we need a space character and we get any whitespace character, or if we need a '0' and we get a '1' (this is so that we only need one state to handle ``.mri 0'' and ``.mri 1''). */ if (ch != '\0' && (*mri_state == ch || (*mri_state == ' ' && lex[ch] == LEX_IS_WHITESPACE) || (*mri_state == '0' && ch == '1'))) { mri_last_ch = ch; ++mri_state; } else if (*mri_state != '\0' || (lex[ch] != LEX_IS_WHITESPACE && lex[ch] != LEX_IS_NEWLINE)) { /* We did not get the expected character, or we didn't get a valid terminating character after seeing the entire pseudo-op, so we must go back to the beginning. */ mri_state = NULL; } else { /* We've read the entire pseudo-op. mips_last_ch is either '0' or '1' indicating whether to enter or leave MRI mode. */ do_scrub_begin (mri_last_ch == '1'); /* We continue handling the character as usual. The main gas reader must also handle the .mri pseudo-op to control expression parsing and the like. */ } } #endif if (ch == EOF) { if (state != 0) { as_warn ("end of file not at end of a line; newline inserted"); state = 0; PUT ('\n'); } goto fromeof; } switch (lex[ch]) { case LEX_IS_WHITESPACE: do { ch = GET (); } while (ch != EOF && IS_WHITESPACE (ch)); if (ch == EOF) goto fromeof; if (state == 0) { /* Preserve a single whitespace character at the beginning of a line. */ state = 1; UNGET (ch); PUT (' '); break; } if (IS_COMMENT (ch) || ch == '/' || IS_LINE_SEPARATOR (ch)) { if (scrub_m68k_mri) { /* In MRI mode, we keep these spaces. */ UNGET (ch); PUT (' '); break; } goto recycle; } /* If we're in state 2 or 11, we've seen a non-white character followed by whitespace. If the next character is ':', this is whitespace after a label name which we normally must ignore. In MRI mode, though, spaces are not permitted between the label and the colon. */ if ((state == 2 || state == 11) && lex[ch] == LEX_IS_COLON && ! scrub_m68k_mri) { state = 1; PUT (ch); break; } switch (state) { case 0: state++; goto recycle; /* Punted leading sp */ case 1: /* We can arrive here if we leave a leading whitespace character at the beginning of a line. */ goto recycle; case 2: state = 3; if (to + 1 < toend) { /* Optimize common case by skipping UNGET/GET. */ PUT (' '); /* Sp after opco */ goto recycle; } UNGET (ch); PUT (' '); break; case 3: if (scrub_m68k_mri) { /* In MRI mode, we keep these spaces. */ UNGET (ch); PUT (' '); break; } goto recycle; /* Sp in operands */ case 9: case 10: if (scrub_m68k_mri) { /* In MRI mode, we keep these spaces. */ state = 3; UNGET (ch); PUT (' '); break; } state = 10; /* Sp after symbol char */ goto recycle; case 11: if (flag_m68k_mri #ifdef LABELS_WITHOUT_COLONS || 1 #endif ) state = 1; else { /* We know that ch is not ':', since we tested that case above. Therefore this is not a label, so it must be the opcode, and we've just seen the whitespace after it. */ state = 3; } UNGET (ch); PUT (' '); /* Sp after label definition. */ break; default: BAD_CASE (state); } break; case LEX_IS_TWOCHAR_COMMENT_1ST: ch2 = GET (); if (ch2 != EOF && lex[ch2] == LEX_IS_TWOCHAR_COMMENT_2ND) { for (;;) { do { ch2 = GET (); if (ch2 != EOF && IS_NEWLINE (ch2)) add_newlines++; } while (ch2 != EOF && (lex[ch2] != LEX_IS_TWOCHAR_COMMENT_2ND)); while (ch2 != EOF && (lex[ch2] == LEX_IS_TWOCHAR_COMMENT_2ND)) { ch2 = GET (); } if (ch2 == EOF || lex[ch2] == LEX_IS_TWOCHAR_COMMENT_1ST) break; UNGET (ch2); } if (ch2 == EOF) as_warn ("end of file in multiline comment"); ch = ' '; goto recycle; } else { if (ch2 != EOF) UNGET (ch2); if (state == 9 || state == 10) state = 3; PUT (ch); } break; case LEX_IS_STRINGQUOTE: if (state == 10) { /* Preserve the whitespace in foo "bar" */ UNGET (ch); state = 3; PUT (' '); /* PUT didn't jump out. We could just break, but we know what will happen, so optimize a bit. */ ch = GET (); old_state = 3; } else if (state == 9) old_state = 3; else old_state = state; state = 5; PUT (ch); break; #ifndef IEEE_STYLE case LEX_IS_ONECHAR_QUOTE: if (state == 10) { /* Preserve the whitespace in foo 'b' */ UNGET (ch); state = 3; PUT (' '); break; } ch = GET (); if (ch == EOF) { as_warn ("end of file after a one-character quote; \\0 inserted"); ch = 0; } if (ch == '\\') { ch = GET (); if (ch == EOF) { as_warn ("end of file in escape character"); ch = '\\'; } else ch = process_escape (ch); } sprintf (out_buf, "%d", (int) (unsigned char) ch); /* None of these 'x constants for us. We want 'x'. */ if ((ch = GET ()) != '\'') { #ifdef REQUIRE_CHAR_CLOSE_QUOTE as_warn ("Missing close quote: (assumed)"); #else if (ch != EOF) UNGET (ch); #endif } if (strlen (out_buf) == 1) { PUT (out_buf[0]); break; } if (state == 9) old_state = 3; else old_state = state; state = -1; out_string = out_buf; PUT (*out_string++); break; #endif case LEX_IS_COLON: if (state == 9 || state == 10) state = 3; else if (state != 3) state = 1; PUT (ch); break; case LEX_IS_NEWLINE: /* Roll out a bunch of newlines from inside comments, etc. */ if (add_newlines) { --add_newlines; UNGET (ch); } /* fall thru into... */ case LEX_IS_LINE_SEPARATOR: state = 0; PUT (ch); break; case LEX_IS_LINE_COMMENT_START: /* FIXME-someday: The two character comment stuff was badly thought out. On i386, we want '/' as line comment start AND we want C style comments. hence this hack. The whole lexical process should be reworked. xoxorich. */ if (ch == '/') { ch2 = GET (); if (ch2 == '*') { state = -2; break; } else { UNGET (ch2); } } /* bad hack */ if (state == 0 || state == 1) /* Only comment at start of line. */ { int startch; startch = ch; do { ch = GET (); } while (ch != EOF && IS_WHITESPACE (ch)); if (ch == EOF) { as_warn ("end of file in comment; newline inserted"); PUT ('\n'); break; } if (ch < '0' || ch > '9' || state != 0 || startch != '#') { /* Not a cpp line. */ while (ch != EOF && !IS_NEWLINE (ch)) ch = GET (); if (ch == EOF) as_warn ("EOF in Comment: Newline inserted"); state = 0; PUT ('\n'); break; } /* Loks like `# 123 "filename"' from cpp. */ UNGET (ch); old_state = 4; state = -1; if (scrub_m68k_mri) out_string = "\tappline "; else out_string = "\t.appline "; PUT (*out_string++); break; } /* We have a line comment character which is not at the start of a line. If this is also a normal comment character, fall through. Otherwise treat it as a default character. */ if (strchr (tc_comment_chars, ch) == NULL && (! scrub_m68k_mri || (ch != '!' && ch != '*'))) goto de_fault; if (scrub_m68k_mri && (ch == '!' || ch == '*' || ch == '#') && state != 1 && state != 10) goto de_fault; /* Fall through. */ case LEX_IS_COMMENT_START: do { ch = GET (); } while (ch != EOF && !IS_NEWLINE (ch)); if (ch == EOF) as_warn ("end of file in comment; newline inserted"); state = 0; PUT ('\n'); break; case LEX_IS_SYMBOL_COMPONENT: if (state == 10) { /* This is a symbol character following another symbol character, with whitespace in between. We skipped the whitespace earlier, so output it now. */ UNGET (ch); state = 3; PUT (' '); break; } if (state == 3) state = 9; /* This is a common case. Quickly copy CH and all the following symbol component or normal characters. */ if (to + 1 < toend && mri_state == NULL) { char *s; int len; for (s = from; s < fromend; s++) { int type; ch2 = *s; type = lex[ch2]; if (type != 0 && type != LEX_IS_SYMBOL_COMPONENT) break; } if (s > from) { /* Handle the last character normally, for simplicity. */ --s; } len = s - from; if (len > (toend - to) - 1) len = (toend - to) - 1; if (len > 0) { PUT (ch); if (len > 8) { memcpy (to, from, len); to += len; from += len; } else { switch (len) { case 8: *to++ = *from++; case 7: *to++ = *from++; case 6: *to++ = *from++; case 5: *to++ = *from++; case 4: *to++ = *from++; case 3: *to++ = *from++; case 2: *to++ = *from++; case 1: *to++ = *from++; } } ch = GET (); } } /* Fall through. */ default: de_fault: /* Some relatively `normal' character. */ if (state == 0) { state = 11; /* Now seeing label definition */ } else if (state == 1) { state = 2; /* Ditto */ } else if (state == 9) { if (lex[ch] != LEX_IS_SYMBOL_COMPONENT) state = 3; } else if (state == 10) { state = 3; } PUT (ch); break; } } /*NOTREACHED*/ fromeof: /* We have reached the end of the input. */ return to - tostart; tofull: /* The output buffer is full. Save any input we have not yet processed. */ if (fromend > from) { char *save; save = (char *) xmalloc (fromend - from); memcpy (save, from, fromend - from); if (saved_input != NULL) free (saved_input); saved_input = save; saved_input_len = fromend - from; } else { if (saved_input != NULL) { free (saved_input); saved_input = NULL; } } return to - tostart; } /* end of app.c */