That's a funny statement. Which processors do you include in "most"?
That has not been my experience.
> It's outright stupid to write <<2 when we mean *4 in order to optimize for one out of a
> gazillion supported architectures - even more so when the compiler
> for the one CPU where <<2 is faster, will actually generate a shift
> instead of a multiply as a part of the standard optimization.
>
> One question for the GCC people: Will gcc change <<2 to *4 on other
> architectures ? If so, then my case is not quite as strong of course.
>
gcc should consider the statements equivalent, and generate whichever
pattern is preferred. On an i386 that may mean take a pattern such as
foo = (bar << 2) + quux;
... and generate ...
lea ecx,[esi*4+ebx]
-hpa
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