From a187ac959abfbe030c4733315820aa4a038ff1bc Mon Sep 17 00:00:00 2001 From: Richard Stallman Date: Tue, 30 Jun 1992 03:11:04 +0000 Subject: [PATCH] Initial revision From-SVN: r1357 --- gcc/c-pragma.c | 219 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 219 insertions(+) create mode 100644 gcc/c-pragma.c diff --git a/gcc/c-pragma.c b/gcc/c-pragma.c new file mode 100644 index 0000000..4cfd090 --- /dev/null +++ b/gcc/c-pragma.c @@ -0,0 +1,219 @@ +/* Handle #pragma, system V.4 style. Supports #pragma weak and #pragma pack. + Copyright (C) 1992 Free Software Foundation, Inc. + +This file is part of GNU CC. + +GNU CC 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. + +GNU CC 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 GNU CC; see the file COPYING. If not, write to +the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ + +#ifdef HANDLE_SYSV_PRAGMA + +/* When structure field packing is in effect, this variable is the + number of bits to use as the maximum alignment. When packing is not + in effect, this is zero. */ + +extern int maximum_field_alignment; + +/* Handle a #pragma directive. INPUT is the current input stream, + and C is a character to reread. + Returns a character for the caller to reread, + or -1 meaning there isn't one. */ + +int +handle_sysv_pragma (input, c) + FILE *input; + int c; +{ + while (c == ' ' || c == '\t') + c = getc (input); + if (c == '\n' || c == EOF) + { + handle_pragma_token (0, 0); + return c; + } + ungetc (c, input); + switch (yylex ()) + { + case IDENTIFIER: + case TYPENAME: + case STRING: + case CONSTANT: + handle_pragma_token (token_buffer, yylval.ttype); + break; + default: + handle_pragma_token (token_buffer, 0); + } + return -1; +} + +/* Handle one token of a pragma directive. TOKEN is the + current token, and STRING is its printable form. */ + +void +handle_pragma_token (string, token) + char *string; + tree token; +{ + static enum pragma_state + { + ps_start, + ps_done, + ps_bad, + ps_weak, + ps_name, + ps_equals, + ps_value, + ps_pack, + ps_left, + ps_align, + ps_right + } state = ps_start, type; + static char *name; + static char *value; + static int align; + + if (string == 0) + { + if (type == ps_pack) + { + if (state == ps_right) + maximum_field_alignment = align * 8; + else + warning ("malformed `#pragma pack'"); + } +#ifdef WEAK_ASM_OP + else if (type == ps_weak) + { + if (state == ps_name || state == ps_value) + { + fprintf (asm_out_file, "\t%s\t", WEAK_ASM_OP); + ASM_OUTPUT_LABELREF (asm_out_file, name); + fputc ('\n', asm_out_file); + if (state == ps_value) + { + fprintf (asm_out_file, "\t%s\t", SET_ASM_OP); + ASM_OUTPUT_LABELREF (asm_out_file, name); + fputc (',', asm_out_file); + ASM_OUTPUT_LABELREF (asm_out_file, value); + fputc ('\n', asm_out_file); + } + } + else if (! (state == ps_done || state == ps_start)) + warning ("malformed `#pragma weak'"); + } +#endif /* WEAK_ASM_OP */ + + type = state = ps_start; + return; + } + + switch (state) + { + case ps_start: + if (token && TREE_CODE (token) == IDENTIFIER_NODE) + { + if (strcmp (IDENTIFIER_POINTER (token), "pack") == 0) + type = state = ps_pack; +#ifdef WEAK_ASM_OP + else if (strcmp (IDENTIFIER_POINTER (token), "weak") == 0) + type = state = ps_weak; +#endif + else + type = state = ps_done; + } + else + type = state = ps_done; + break; + +#ifdef WEAK_ASM_OP + case ps_weak: + if (token && TREE_CODE (token) == IDENTIFIER_NODE) + { + name = IDENTIFIER_POINTER (token); + state = ps_name; + } + else + state = ps_bad; + break; + + case ps_name: + state = (strcmp (string, "=") ? ps_bad : ps_equals); + break; + + case ps_equals: + if (token && TREE_CODE (token) == IDENTIFIER_NODE) + { + value = IDENTIFIER_POINTER (token); + state = ps_value; + } + else + state = ps_bad; + break; + + case ps_value: + state = ps_bad; + break; +#endif /* WEAK_ASM_OP */ + + case ps_pack: + if (strcmp (string, "(") == 0) + state = ps_left; + else + state = ps_bad; + break; + + case ps_left: + if (token && TREE_CODE (token) == INTEGER_CST + && TREE_INT_CST_HIGH (token) == 0) + switch (TREE_INT_CST_LOW (token)) + { + case 1: + case 2: + case 4: + align = TREE_INT_CST_LOW (token); + state = ps_align; + break; + + default: + state = ps_bad; + } + else if (! token && strcmp (string, ")") == 0) + { + align = 0; + state = ps_right; + } + else + state = ps_bad; + break; + + case ps_align: + if (strcmp (string, ")") == 0) + state = ps_right; + else + state = ps_bad; + break; + + case ps_right: + state = ps_bad; + break; + + case ps_bad: + case ps_done: + break; + + default: + abort (); + } +} +#endif /* HANDLE_SYSV_PRAGMA */ -- 2.7.4