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Loop unrolling bug still present


It was stated that in the second prerelease of GCC-3.3.4 from 30 May 2004
the -funroll-loop miscompilation has been fixed.

That is true for the default option set. 

However, if you use the options

    -O2 -funroll-loops --param max-unrolled-insns=xxx

execution of memcpy-1.c will still fail for all xxx > 192
(I only tested PowerPC target)

On PowerPC (G5) I found that --param max-unrolled-insns=600 results 
in about 20% - 30% higher speed in my application (mostly Altivec image
processing).

Michael Cieslinski




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