On Mon, 2008-08-11 at 18:07 -0700, Brian Dessent wrote: > Because the MSVC style of inline assembler doesn't allow for specifying > any constraints such as which registers or stack slots are clobbered. > This means that compiler can't assume anything about the state before > and after the block, it must just throw away all dataflow information it > had before the block and assume everything was clobbered, leading to > tons of useless redundant loads/stores. The GNU style inline asm works > within the framework of the optimizing compiler, rather than outside it > by totally going behind it's back. > > Read the long thread that starts here: > <http://gcc.gnu.org/ml/gcc/2004-05/threads.html#00070>. Thank you for the explanation and the link. I've never been a Microsoft programmer, and I haven't used CodeWarrior (Mac PowerPC) for a long time. I had forgotten about that technique of inline assembly. Bob
