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author | imp <imp@FreeBSD.org> | 1999-03-01 06:27:31 +0000 |
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committer | imp <imp@FreeBSD.org> | 1999-03-01 06:27:31 +0000 |
commit | a33e5716f56ac0e54bf6051df6b0889247455209 (patch) | |
tree | 7416fec1b45002adff46133f13305dbd48bfd06a /contrib/libgmp/mpn/mips3/README | |
parent | 7fbf66313a44405a9d9a78c90611dad3c0597620 (diff) | |
download | FreeBSD-src-a33e5716f56ac0e54bf6051df6b0889247455209.zip FreeBSD-src-a33e5716f56ac0e54bf6051df6b0889247455209.tar.gz |
Import mips2 and mips3 files from the 2.0.2 gmp distribution.
Approved by: markm
Diffstat (limited to 'contrib/libgmp/mpn/mips3/README')
-rw-r--r-- | contrib/libgmp/mpn/mips3/README | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/contrib/libgmp/mpn/mips3/README b/contrib/libgmp/mpn/mips3/README new file mode 100644 index 0000000..e94b2c7 --- /dev/null +++ b/contrib/libgmp/mpn/mips3/README @@ -0,0 +1,23 @@ +This directory contains mpn functions optimized for MIPS3. Example of +processors that implement MIPS3 are R4000, R4400, R4600, R4700, and R8000. + +RELEVANT OPTIMIZATION ISSUES + +1. On the R4000 and R4400, branches, both the plain and the "likely" ones, + take 3 cycles to execute. (The fastest possible loop will take 4 cycles, + because of the delay insn.) + + On the R4600, branches takes a single cycle + + On the R8000, branches often take no noticable cycles, as they are + executed in a separate function unit.. + +2. The R4000 and R4400 have a load latency of 4 cycles. + +3. On the R4000 and R4400, multiplies take a data-dependent number of + cycles, contrary to the SGI documentation. There seem to be 3 or 4 + possible latencies. + +STATUS + +Good... |