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Re: Serious code generation/optimisation bug (I think)
On 2009-01-28 16:34:29 -0500, Robert Dewar wrote:
> If 0 is a valid address, then it is improper for the compiler to use
> 0 to represent the null pointer.
I disagree. You can represent addresses with some bit set. If in
practice (at the processor level), this bit is ignored, then this
can really be efficient. For instance, IIRC, the 68000 ignored
the top 8 bits of a register when regarding its value as an
address (a 32-bit register could address a 24-bit address space).
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Vincent Lefèvre <vincent@vinc17.org> - Web: <http://www.vinc17.org/>
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