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Reduce tables to 8bit #2930

Merged
merged 2 commits into from
Dec 15, 2021
Merged

Reduce tables to 8bit #2930

merged 2 commits into from
Dec 15, 2021

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nolange
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@nolange nolange commented Dec 14, 2021

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@nolange
Add typedefs for 8bit (un)signed
99923df 
To make code more expressive, add U8 and S8 typedefs
@nolange
Reduce bit tables to 8bit
2fbb1d1 
This saves some 1.7Kb in rodata section (x86_64, zstd tool),
while assembler code stays the same except
the type of a few load/extend instructions.

Should not have negative performance implications.
felixhandte
felixhandte approved these changes Dec 15, 2021
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Looks like this saves 4KB. Cool!

I looked at the disassembled diff on amd64 and confirmed that this just replaces mov instructions with movzbl, so it should otherwise be a total no-op.

@felixhandte felixhandte merged commit d5933a4 into facebook:dev Dec 15, 2021
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@felixhandte felixhandte felixhandte approved these changes

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@nolange @felixhandte @facebook-github-bot