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view lwar/list.c @ 426:b4825b42c151
Change to engage forwardrefmax pragma by default
There are enough cases where the forward reference optimization scheme in
lwasm makes assembly painfully slow that it warrants enabling this pragma by
default to avoid bug reports about lwasm being too slow. Which is is when
you have a lot of forward refences or other instruction sizes that don't
reduce on pass one. This gets worse exponentially as the source file size
gets bigger.
The old behaviour is available to anyone who needs or wants it, though. It
does work quite well on smallish files or files that do not have a lot of
abiguous instruction sizes.
It should be noted that this change does not change the correctness of the
code output by lwasm. What it might do is result in slightly larger code if
the assembler is forced to select a 16 bit mode when an 8 bit mode will do.
However, in most cases I've seen, it makes very little difference overall.
author | William Astle <lost@l-w.ca> |
---|---|
date | Thu, 03 Nov 2016 21:44:32 -0600 |
parents | 6f4c4d59666f |
children |
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/* list.c Copyright © 2009 William Astle This file is part of LWAR. LWAR 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 3 of the License, or (at your option) any later version. This program 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 this program. If not, see <http://www.gnu.org/licenses/>. Implements the program startup code */ #include <errno.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include "lwar.h" void do_list(void) { FILE *f; char buf[8]; long l; int c; f = fopen(archive_file, "rb"); if (!f) { perror("Opening archive file"); exit(1); } (void)(fread(buf, 1, 6, f) && 1); if (memcmp("LWAR1V", buf, 6)) { fprintf(stderr, "%s is not a valid archive file.\n", archive_file); exit(1); } for (;;) { c = fgetc(f); if (ferror(f)) { perror("Reading archive file"); exit(1); } if (c == EOF) return; // find the end of the file name if (!c) return; while (c) { putchar(c); c = fgetc(f); if (c == EOF || ferror(f)) { fprintf(stderr, "Bad archive file\n"); exit(1); } } // get length of archive member l = 0; c = fgetc(f); l = c << 24; c = fgetc(f); l |= c << 16; c = fgetc(f); l |= c << 8; c = fgetc(f); l |= c; printf(": %04lx bytes\n", l); fseek(f, l, SEEK_CUR); } }