improve XBurst performance by tuning interlocks/hazards #130
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The internal XBurst architecture isn't known. There is only information
about interlock cycles in the programming manuals so the numbers are
figured by testing execution speed of asm patterns which reflect to
specific interlocks.
The patch doesn't change MIPS32r2 automaton which corresponds to 74k.md.
Signed-off-by: Siarhei Volkau <[email protected]>
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I found that it is not good enough and getting code worse sometimes. |
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The MIPS32r1 uses automaton for R4000 CPU located in
4k.md, however XBurst has different architecture and 4k interlock definitions aren't fit well.The patch for GCC compiler changes the interlocks to be close to XBurst core interlocks.
However, the patch doesn't change anything for MIPS32r2 XBurst cores as the MIPS32r2 uses 74K core automaton defined in
74k.mdand I have no such hardware to test the patch on.The rough performance improvement is 2.5%, tested on fceux only (not the whole system).