Preventing scheduling of normal operations across calls to built-ins

Ian Lance Taylor iant@google.com
Wed Feb 22 01:55:00 GMT 2012


Ayonam Ray <ayonam@gmail.com> writes:

> What I can't understand is that why is the RTL reordered right at the
> expand stage itself.  If I turn off the optimization, then the reorder
> at the expand stage doesn't happen.  This can be seen in the expand
> output at -O0.  I am wondering if there is some issue with the manner
> in which the built-ins are initialized which makes the compiler think
> that they do not affect program state.

It looks like the function calls are being rearranged before you ever
get to the RTL.  What does your original source code look like?  How
precisely are you defining the builtin functions?

Ian



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