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Use a single 'ld' to read the jmpbuf magic values instead of 'la; ld'.
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Authored by jhb on Dec 3 2019, 10:18 PM.
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Details

Summary

This saves an instruction in each case.

Test Plan
  • tests in /usr/tests/lib/libc/setjmp pass

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rS FreeBSD src repository - subversion
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This is particularly beneficial as, for PIC code, which this will almost always be, la expands to auipc/ld to index the GOT, so we save a level of unnecessary indirection too. (This could have been lla instead to save the indirection but still take 2 instructions just to do the address calculation.)

This revision is now accepted and ready to land.Dec 4 2019, 2:40 PM