ARMv7 block profiling + minor optimization #1559
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Enable support for not loading a destination register on FPR cache. Dump registers if they won't be used later in the block. Stolen from Fiora.
This was interesting implementing. Our generic QueryPerformanceCounter function on ARMv7 was so slow that profiling a block was impossible. I waited about five minutes and I couldn't even get a single frame to output. This instead uses ARMv7's PMU to get cycle counts, which are a relatively minor performance drop in my testing. One disadvantage of this method is that the kernel can lock us out of using these co-processor registers, but it seems to work on my Jetson board. Another disadvantage is that we aren't having block times in "real" time but cycles instead, not too big of a deal. This also removes instruction run counts from profiling because that's just annoying and we don't expose an interface for even getting those results from our UI.
skidau
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Nov 18, 2014
ARMv7 block profiling + minor optimization
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This adds ARMv7 block profiling, and also a minor optimization with dumping registers if they are no longer used in a block, which I shamelessly stole from Fiora.