------- Comment #26 from kenner at vlsi1 dot ultra dot nyu dot edu 2007-03-08 12:54 ------- Subject: Re: [4.3 regression] ACATS cxh1001 fails
> y = __builtin_nop(x); valid = (y>=lower_bound && y <=upper_bound); > The point is that the intrinsic would be opaque to the optimizers, > and would only be lowered to the identity function *after* the tree > optimizers have run. One annoyance is that presumably intrinsics > would be needed for all integer and float precisions, eg > __builtin_nop8, __builtin_nop16, etc. More than each precision. The VIEW_CONVERT_EXPR is to the base type and there can be an unlimited number of them for each precision. Because it has to work with arbitrary types, a builtin won't do it. We could certainly add a new tree expression that says "don't look through this for VRP purposes", but we already have V_C_E. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=26797
