PowerPC 64 x 32 bits performance

[Robert Dewar]

Alan Modra wrote:

> These are most likey 64-bit address constant loads.  On ppc32, a 32-bit
> address constant can be calculated in at most 2 instructions.  A 64-bit
> address takes up to 5 instructions to calculate in-line, or a TOC memory
> load.

One general principle at work here is that there is no rule that 64-bit
code will be faster than 32-bit code. On the contrary, one generally
expects 32-bit code to be faster in many cases.