)]}'
{
  "commit": "bb7242477c2f36195b53018b58a77f1dc12ffb06",
  "tree": "f49010cf38489e972b4254c2709c9c489e5554c7",
  "parents": [
    "8231dd71cb7dce489f4499a4e4f0ec149e858087"
  ],
  "author": {
    "name": "Reid Kleckner",
    "email": "rnk@google.com",
    "time": "Wed Jun 25 06:23:11 2025 -0600"
  },
  "committer": {
    "name": "GitHub",
    "email": "noreply@github.com",
    "time": "Wed Jun 25 05:23:11 2025 -0700"
  },
  "message": "[MC] Use StringTable to reduce dynamic relocations (#144202)\n\nDynamic relocations are expensive on ELF/Linux platforms because they\nare applied in userspace on process startup. Therefore, it is worth\noptimizing them to make PIE and PIC dylib builds faster. In +asserts\nbuilds (non-NDEBUG), nikic identified these schedule class name string\npointers as the leading source of dynamic relocations. [1]\n\nThis change uses llvm::StringTable and the StringToOffsetTable TableGen\nhelper to turn the string pointers into 32-bit offsets into a separate\ncharacter array.\n\nThe number of dynamic relocations is reduced by ~60%:\n❯ llvm-readelf --dyn-relocations lib/libLLVM.so | wc -l\n381376 # before\n155156 # after\n\nThe test suite time is modestly affected, but I\u0027m running on a shared\nnoisy workstation VM with a ton of cores:\nhttps://gist.github.com/rnk/f38882c2fe2e63d0eb58b8fffeab69de\nTesting Time: 100.88s   # before\nTesting Time: 78.50s. # after\nTesting Time: 96.25s.  # before again\n\nI haven\u0027t used any fancy hyperfine/denoising tools, but I think the\nresult is clearly visible and we should ship it.\n\n[1] https://gist.github.com/nikic/554f0a544ca15d5219788f1030f78c5a",
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