On Fri, 2007-08-03 at 17:24 +0100, Dave Korn wrote: > > I am not surprised that there is different behavior for different > > targets, but I am very surprised that *this* behavior is different. This > > optimization ought to be happening in the mid-end, and it ought to be > > entirely machine independent. > > I'm a bit surprised too. But it occurs to me that the ARM, unlike the i386 > and m68k, is bi-endian. Perhaps you can't actually know which mode it's > running in at compile time and /have/ to test it at runtime?
That seems counter-intuitive, since a given compiler instance is configured for a target with a particular endian-ness. Even if the compiler can evade knowledge, the assembler surely must know. Of course, I am not running the assembler here. In any case, an interesting hypothesis. Would also explain some code pessimization issues for ARM targets more generally. shap
