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Re: FLOATING-POINT CONSISTENCY, -FFLOAT-STORE, AND X86
- To: rth at cygnus dot com, hjstein at bfr dot co dot il, toon at moene dot indiv dot nluug dot nl
- Subject: Re: FLOATING-POINT CONSISTENCY, -FFLOAT-STORE, AND X86
- From: N8TM at aol dot com
- Date: Sat, 19 Dec 1998 02:07:02 EST
- Cc: egcs at cygnus dot com
In a message dated 12/18/98 10:36:15 PM Pacific Standard Time, rth@cygnus.com
writes:
<< I have not tried quantifing the change. I would want to examine
things more closely, however, because 25% seems low to me. >>
Some proponents of the idea felt that spills were so rare that no difference
would be seen regardless of the efficiency of an 80-bit spilling
implementation. My 25% figure is for a complete execution of the application;
certainly there must be sections of this application where the 80-bit spills
are doubling the time spent. That means the 80-bit spills, a majority of them
mis-aligned, are taking several times as long as the 32-bit spills.
As I'm seeing so many implementations where 64-bit spills are mis-aligned,
I'd like to see the alignment problem solved before I'm stuck with wider
spills.