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  1. WiredTiger
  2. WT-2440

vpmsum_crc32: Per the PPC64 ABI, v20-v31 are non-volatile register

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Fixed
    • Affects Version/s: None
    • Fix Version/s: WT2.8.0
    • Component/s: None

      Description

      See http://refspecs.linuxfoundation.org/ELF/ppc64/PPC-elf64abi.html#REG for calling convention.

      In experiments under GDB, we see that after crc32_vpmsum is called that registers v20-v31 are modified. We discovered this issue after integrating the crc32_vpmsum code into our C++ code base which targeted POWER8 for code generation, see https://jira.mongodb.org/browse/SERVER-22773 for repro.

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              Assignee:
              mark.benvenuto Mark Benvenuto
              Reporter:
              mark.benvenuto Mark Benvenuto
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                Updated:
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