[aarch64] Allocate LJ_TISNUM early #70
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LJ_TISNUM is allocated too late in the cycle and it ends up reusing a different register, resulting in a crash under register pressure. Hoist the allocation to the top so that it is done early enough and the allowed register set no longer contains that register. This also has the nice side effect of beig slightly faster since it hoists a constant allocation out of the generated loop.
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Merged. Thanks. |
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Just for the record, this bug led to random crashes when fuzzing our edgelang and ylang compilers on aarch64. And random seed numbers had to be used to feed the API function jit.prngstate to reproduce this more frequently. And this work was sponsored by OpenResty Inc :) |
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LJ_TISNUM is allocated too late in the cycle and it ends up reusing a
different register, resulting in a crash under register pressure.
Hoist the allocation to the top so that it is done early enough and
the allowed register set no longer contains that register. This also
has the nice side effect of beig slightly faster since it hoists a
constant allocation out of the generated loop.