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[Bcc to 15 developers] Hi! I've been looking at the old EP93xx MaverickCrunch FPU patches for GCC again and almost have a working set for gcc-4.4. It "seems to work" for most programs but one FP-math-intensive testsuite is failing.(*) The good news is that FFTW's speed test reports an increase from 6.13 to 7.65 MFlops and I think I now know what was wrong with the 64-bit integer arithmetic(**): fixing that should bring a speed increase to OpenSSL and others. It also integrates better with the new Debian release "wheezy", whose minimum GCC version is now 4.4. I'm writing as a fundraiser to prod me into finding and applying the bug fix, and finish, package and publish it, to then compile the Debian repository of crunch-acelerated packages for wheezy. So if anyone happens to work for a company that gains form my work, do feel free to campaign with the accountants on my behalf :) In any case, I'll write again when the new compiler and repositories are available. Cheers M *) In fftw. It looks like another variant of a known silicon bug: when one instruction modifies an ARM register ina a way that induces a wait state, and the next instruction is a crunch double load/store whose address indirects through that register, the result is garbage or RAM is corrupted at random. **) By default, its 64-bit arithmetic operations do saturating arithmetic instead of "going round the clock", maxing out at 0x7F* and -0x80*. The only place that notices is openssl's 64-bit-optimized bignum div/rem function. -- For unsubscribe information see http://sourceware.org/lists.html#faq
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