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%% John Clark <jclark@metricsystems.com> writes: Thanks for replying, John! >> the Linux version of the compiler generates this assembly code: >> >> mulli 9,0,100 >> stw 9,28(31) >> >> while the Solaris version generates this assembly code: >> >> mr 11,0 >> slwi 9,11,1 >> add 9,9,0 >> slwi 11,9,5 >> add 9,9,11 >> add 0,9,0 >> stw 0,28(31) jc> I would conjecture that the above is due to some form of option jc> that selects a 'mul' over a shift and add implementation. That jc> could be based on machine type (ie which PPC implementation) or jc> optimizer settings, again conditioned on machine type, that the jc> new compiler defaults to. (PPC things for me are pretty ancient, jc> but arn't there versions which don't have a multiply?) Well, the compile lines I use to generate the .s files on both systems are byte-for-byte identical, so it's not the command-line flags (optimization levels, -f arch settings, etc.) I've also looked at the ccppc -v output and compared those: no differences. The spec file that was installed for Linux was very different than the one for Solaris. However, I did try copying the Solaris spec file over into the Linux compiler installation and that didn't help either. I'm about out of ideas, other than the obvious: I have the wrong source code :-/. Any pointers to good sources of information on this subject? -- ------------------------------------------------------------------------------- Paul D. Smith <psmith@nortel.com> HASMAT--HA Software Mthds & Tools "Please remain calm...I may be mad, but I am a professional." --Mad Scientist ------------------------------------------------------------------------------- These are my opinions--Nortel takes no responsibility for them. -- For unsubscribe information see http://sourceware.org/lists.html#faq
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