Method removeUnreachableCode

libraries/asmjit/asmjit/base/regalloc.cpp:303–348

// ============================================================================

Error RAPass::removeUnreachableCode() {
  ZoneList<CBNode*>::Link* link = _unreachableList.getFirst();
  CBNode* stop = getStop();

  while (link) {
    CBNode* node = link->getValue();
    if (node && node->getPrev() && node != stop) {
      // Locate all unreachable nodes.
      CBNode* first = node;
      do {
        if (node->hasPassData()) break;
        node = node->getNext();
      } while (node != stop);

      // Remove unreachable nodes that are neither informative nor directives.
      if (node != first) {
        CBNode* end = node;
        node = first;

        // NOTE: The strategy is as follows:
        // 1. The algorithm removes everything until it finds a first label.
        // 2. After the first label is found it removes only removable nodes.
        bool removeEverything = true;
        do {
          CBNode* next = node->getNext();
          bool remove = node->isRemovable();

          if (!remove) {
            if (node->isLabel())
              removeEverything = false;
            remove = removeEverything;
          }

          if (remove)
            cc()->removeNode(node);

          node = next;
        } while (node != end);
      }
    }

    link = link->getNext();
  }

  return kErrorOk;
}

// ============================================================================
// [asmjit::RAPass - Liveness Analysis]