From: Sebastian <git@sraa.de>
Date: Wed, 30 Jul 2014 18:46:05 +0000 (+0000)
Subject: shared: don't pack shm_t, but align it instead
X-Git-Url: http://sraa.de/git/%3CTMPL_VAR%20NAME=URL%3E?a=commitdiff_plain;h=3b6424ef50be6a7d89d6cd02b48bf10469cb0bad;p=lattice-boltzmann-epiphany.git

shared: don't pack shm_t, but align it instead

Accesses to the poll flag or the iteration counter do not
result in four byte-accesses anymore. Sigh.
---

diff --git a/lb/shared.h b/lb/shared.h
index 512ee95..607a3e1 100644
--- a/lb/shared.h
+++ b/lb/shared.h
@@ -7,9 +7,10 @@
 /* preprocessor magic */
 #define BUILD_BUG(c) do { ((void)sizeof(char[1 - 2*!!(c)])); } while(0);
 #define UNUSED __attribute__((unused))
-#ifndef PACKED
-#	define PACKED __attribute__((packed))
-#endif /* PACKED */
+#undef PACKED
+#define PACKED __attribute__((packed))
+#undef ALIGN
+#define ALIGN(X) __attribute__((aligned(X)))
 
 /* number of cores */
 #define CORES_X 4
@@ -40,7 +41,7 @@ typedef struct {
 	uint32_t     iteration;
 	uint32_t     timers[CORES_Y][CORES_X][TIMERS];
 	d2q9_block_t lattice[CORES_Y][CORES_X];
-} PACKED shm_t;
+} ALIGN(8) shm_t;
 
 #endif /* _SHARED_H_ */