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libc/string/memset.c: Use unsigned long for stores
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Authored by arichardson on Apr 1 2021, 2:38 PM.

Details

Summary

While most 64-bit architectures have an assembly implementation of this
file, RISC-V does not. As we now store 8 bytes instead of 4 it should speed
up RISC-V.

Diff Detail

Repository
R10 FreeBSD src repository
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

Would (u)intptr_t make more sense so it's faster on CHERI? Doesn't make a difference upstream but does to us.

Would (u)intptr_t make more sense so it's faster on CHERI? Doesn't make a difference upstream but does to us.

I thought about that, but that would require additional changes to create an all-ones capability register.

Would (u)intptr_t make more sense so it's faster on CHERI? Doesn't make a difference upstream but does to us.

I thought about that, but that would require additional changes to create an all-ones capability register.

Oh, right, memset not bzero, never mind then

kib added inline comments.
lib/libc/string/memset.c
91

Did you considered lowering 3 to e.g. 2?

This revision is now accepted and ready to land.Apr 15 2021, 11:34 AM
lib/libc/string/memset.c
91

This might make sense but I feel uncomfortable making that change without benchmarks.

Drop #undef and add a TODO comment for the threshold

This revision now requires review to proceed.Mon, Apr 19, 10:50 AM
This revision was not accepted when it landed; it landed in state Needs Review.Tue, Apr 20, 12:47 AM
This revision was automatically updated to reflect the committed changes.