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authoroharboe <oharboe@b42882b7-edfa-0310-969c-e2dbd0fdcd60>2008-12-19 14:48:00 +0000
committeroharboe <oharboe@b42882b7-edfa-0310-969c-e2dbd0fdcd60>2008-12-19 14:48:00 +0000
commit865c5dcc2a0d27ded9135acf7fd1066f55acf5ca (patch)
tree92a122afe7b19caf208044882178b892d2f480a7
parent9d1f95e01a4d273bd0e82a98719a4ea5ff435647 (diff)
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Dick Hollenbeck <dick@softplc.com> better comments
git-svn-id: svn://svn.berlios.de/openocd/trunk@1261 b42882b7-edfa-0310-969c-e2dbd0fdcd60
-rw-r--r--src/helper/types.h22
1 files changed, 13 insertions, 9 deletions
diff --git a/src/helper/types.h b/src/helper/types.h
index e4b37a42..82368a92 100644
--- a/src/helper/types.h
+++ b/src/helper/types.h
@@ -46,18 +46,22 @@ typedef unsigned long long u64;
typedef struct jtag_tap_s jtag_tap_t;
-/* DANGER!!!! here be dragons!
- *
+/* DANGER!!!! here be dragons!
+ *
* Leave these fn's as byte accesses because it is safe
* across architectures. Clever usage of 32 bit access
* will create problems on some hosts.
- *
- * Note that the pointer in memory might be unaligned.
- *
- * On some CPU's, i.e. ARM7, the 2 lsb are ignored for 32
- * bit access, on others it will cause an exception and
- * on e.g. x86, it works the same as if aligned.
- *
+ *
+ * Note that the "buf" pointer in memory is probably unaligned.
+ *
+ * Were these functions to be re-written to take a 32 bit wide or 16 bit wide
+ * memory access shortcut, then on some CPU's, i.e. ARM7, the 2 lsbytes of the address are
+ * ignored for 32 bit access, whereas on other CPU's a 32 bit wide unaligned memory access
+ * will cause an exception, and lastly on x86, an unaligned "greater than bytewide"
+ * memory access works as if aligned. So what follows below will work for all
+ * platforms and gives the compiler leeway to do its own platform specific optimizations.
+ *
+ * Again, note that the "buf" pointer in memory is probably unaligned.
*/