From: Mathieu Desnoyers <mathieu.desnoyers@xxxxxxxxxxxx> Date: Wed, 19 Jan 2011 17:13:27 -0500 > Hrm, I'd like to see what kind of ill-conceived 32-bit architecture would > generate a unaligned access for a 32-bit aligned u64. Do you have examples in > mind ? By definition, the memory accesses should be at most 32-bit, no ? AFAIK, > gcc treats u64 as two distinct reads on all 32-bit architectures. Sparc 32-bit has 64-bit loads and stores, GCC uses them because the ABI specifies that every structure is at least 8 byte aligned. > gcc on my sparc64 box (32-bit userland) disagrees with you here ;) Using > gcc (Debian 4.3.3-14) 4.3.3, here is a demonstration that, indeed, "packed" > generates aweful code, but that "packed, aligned(4 or 8)" generates pretty > decent code: Amazing, if this works then do it. But please document this fully with comments and such :-) -- To unsubscribe from this list: send the line "unsubscribe sparclinux" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
