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Re: [patches] powerpc 8xx dcbz problem



Steven Munroe wrote:

Memset is performance sensitive code and the dynamic __cache_line_size
check is slowing down 970/power4/power5/power5+/power6/power6x. When the
processor can retire (up to) 5 instructions per cycle, the dependent
sequence to address the GOT and check the __cache_line_size is very
noticable.

But I'm not changing that code.  I don't see how it's relevent to your objection.

This is chip specific and 32-bit specific so does not belong in the
trunc. I think this should be a hard and fast rule. If you insist on the
dynamic approach then copy libc-start.c to
ports/sysdeps/unix/sysv/linux/powerpc/powerpc32/ and add the 8xx
specific hack there to zero the __cache_line_size.

ok


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Nathan Sidwell    ::   http://www.codesourcery.com   ::         CodeSourcery
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