3e8655cc49f9b30e73ee54283f0316bbcee74cd2

This version was lagging quite a bit; this one has memory barriers, and
an updated write()

Signed-off-by: Michel Pollet <buserror@gmail.com>

diff --git a/simavr/sim/fifo_declare.h b/simavr/sim/fifo_declare.h
index bbacb3a2d88d20e453eb33a354d6ebc4340b7f89..46c24e786edea2b510374039fe889f04298df262 100644 (file)
--- a/simavr/sim/fifo_declare.h
+++ b/simavr/sim/fifo_declare.h
@@ -1,25 +1,21 @@
 /*
-       fifo_declare.h
+       fido_declare.h
+       Copyright (C) 2003-2012 Michel Pollet <buserror@gmail.com>
 
-       Copyright 2008, 2012 Michel Pollet <buserror@gmail.com>
+       This library is free software; you can redistribute it and/or
+       modify it under the terms of the GNU Lesser General Public
+       License as published by the Free Software Foundation; either
+       version 2.1 of the License, or (at your option) any later version.
 
-       This file is part of simavr.
-
-       simavr 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.
-
-       simavr is distributed in the hope that it will be useful,
+       This library 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.
+       MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+       Lesser General Public License for more details.
 
-       You should have received a copy of the GNU General Public License
-       along with simavr.  If not, see <http://www.gnu.org/licenses/>.
- */
-
-/* Licensed to Vidiactive by Michel Pollet under the terms of the VECL */
+       You should have received a copy of the GNU Lesser General Public
+       License along with this library; if not, write to the Free Software
+       Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+*/
 
 /*
  * FIFO helpers, aka circular buffers
@@ -57,7 +53,7 @@ extern "C" {
                void myfifo_write_at(myfifo_t *c, uint16_t o, uint8_t b);
 
        In your .c you need to 'implement' the fifo:
-       DEFINE_FIFO(uint8_t, myfifo)
+       DEFINE_FIFO(uint8_t, myfifo, 128)
 
        To use the fifo, you must declare at least one :
        myfifo_t fifo = FIFO_NULL;
@@ -75,7 +71,9 @@ extern "C" {
 #define FIFO_CURSOR_TYPE       uint8_t
 #define FIFO_BOOL_TYPE char
 #define FIFO_INLINE
+#define FIFO_SYNC
 #endif
+
 #ifndef        FIFO_CURSOR_TYPE
 #define FIFO_CURSOR_TYPE       uint16_t
 #endif
@@ -86,6 +84,13 @@ extern "C" {
 #define FIFO_INLINE    inline
 #endif
 
+#ifndef FIFO_VOLATILE
+#define FIFO_VOLATILE  volatile
+#endif
+#ifndef FIFO_SYNC
+#define FIFO_SYNC __sync_synchronize()
+#endif
+
 #ifndef FIFO_ZERO_INIT
 #define FIFO_ZERO_INIT {0}
 #endif
@@ -96,9 +101,9 @@ enum { __name##_overflow_f = (1 << 0) }; \
 enum { __name##_fifo_size = (__size) }; \
 typedef struct __name##_t {                    \
        __type          buffer[__name##_fifo_size];             \
-       volatile FIFO_CURSOR_TYPE       read;           \
-       volatile FIFO_CURSOR_TYPE       write;          \
-       volatile uint8_t        flags;          \
+       FIFO_VOLATILE FIFO_CURSOR_TYPE  read;           \
+       FIFO_VOLATILE FIFO_CURSOR_TYPE  write;          \
+       FIFO_VOLATILE uint8_t   flags;          \
 } __name##_t
 
 #define DEFINE_FIFO(__type, __name) \
@@ -108,6 +113,7 @@ static FIFO_INLINE FIFO_BOOL_TYPE __name##_write(__name##_t * c, __type b)\
        FIFO_CURSOR_TYPE next = (now + 1) & (__name##_fifo_size-1);\
        if (c->read != next) {  \
                c->buffer[now] = b;\
+               FIFO_SYNC; \
                c->write = next;\
                return 1;\
        }\
@@ -128,13 +134,18 @@ static FIFO_INLINE __type __name##_read(__name##_t * c)\
        if (c->read == c->write)\
                return res;\
        FIFO_CURSOR_TYPE read = c->read;\
+       FIFO_SYNC; \
        res = c->buffer[read];\
        c->read = (read + 1) & (__name##_fifo_size-1);\
        return res;\
 }\
 static FIFO_INLINE FIFO_CURSOR_TYPE __name##_get_read_size(__name##_t *c)\
 {\
-       return c->write > c->read ? c->write - c->read : __name##_fifo_size - 1 - c->read + c->write;\
+       return ((c->write + __name##_fifo_size) - c->read) & (__name##_fifo_size-1);\
+}\
+static FIFO_INLINE FIFO_CURSOR_TYPE __name##_get_write_size(__name##_t *c)\
+{\
+       return __name##_fifo_size - __name##_get_read_size(c);\
 }\
 static FIFO_INLINE void __name##_read_offset(__name##_t *c, FIFO_CURSOR_TYPE o)\
 {\
@@ -150,6 +161,7 @@ static FIFO_INLINE void __name##_write_at(__name##_t *c, FIFO_CURSOR_TYPE o, __t
 }\
 static FIFO_INLINE void __name##_write_offset(__name##_t *c, FIFO_CURSOR_TYPE o)\
 {\
+       FIFO_SYNC; \
        c->write = (c->write + o) & (__name##_fifo_size-1);\
 }\
 static FIFO_INLINE void __name##_reset(__name##_t *c)\