flowList* Compiler::BlockPredsWithEH(BasicBlock* blk)
{
BlockToFlowListMap* ehPreds = GetBlockToEHPreds();
flowList* res;
if (ehPreds->Lookup(blk, &res))
{
return res;
}
res = blk->bbPreds;
unsigned tryIndex;
if (bbIsExFlowBlock(blk, &tryIndex))
{
// Find the first block of the try.
EHblkDsc* ehblk = ehGetDsc(tryIndex);
BasicBlock* tryStart = ehblk->ebdTryBeg;
for (flowList* tryStartPreds = tryStart->bbPreds; tryStartPreds != nullptr; tryStartPreds = tryStartPreds->flNext)
{
res = new (this, CMK_FlowList) flowList(tryStartPreds->flBlock, res);
#if MEASURE_BLOCK_SIZE
genFlowNodeCnt += 1;
genFlowNodeSize += sizeof(flowList);
#endif // MEASURE_BLOCK_SIZE
}
// Now add all blocks within the try (except for second blocks of BBJ_CALLFINALLY/BBJ_ALWAYS pairs;
// these cannot cause transfer to the handler...)
BasicBlock* prevBB = NULL;
// TODO-Throughput: It would be nice if we could iterate just over the blocks in the try, via
// something like:
// for (BasicBlock* bb = ehblk->ebdTryBeg; bb != ehblk->ebdTryLast->bbNext; bb = bb->bbNext)
// That doesn't work, however: funclets have caused us to sometimes split the body of a try into
// more than one sequence of contiguous blocks. We need to find a better way to do this.
for (BasicBlock* bb = fgFirstBB; bb != NULL; prevBB = bb, bb = bb->bbNext)
{
if (bbInTryRegions(tryIndex, bb) && (prevBB == NULL || !prevBB->isBBCallAlwaysPair()))
{
res = new (this, CMK_FlowList) flowList(bb, res);
#if MEASURE_BLOCK_SIZE
genFlowNodeCnt += 1;
genFlowNodeSize += sizeof(flowList);
#endif // MEASURE_BLOCK_SIZE
}
}
#ifdef DEBUG
unsigned hash = SsaStressHashHelper();
if (hash != 0)
{
res = ShuffleHelper(hash, res);
}
#endif // DEBUG
ehPreds->Set(blk, res);
}
return res;
}
unsigned PtrKeyFuncs<BasicBlock>::GetHashCode(const BasicBlock* ptr)
{
#ifdef DEBUG
unsigned hash = SsaStressHashHelper();
if (hash != 0)
{
return (hash ^ (ptr->bbNum << 16) ^ ptr->bbNum);
}
#endif
return ptr->bbNum;
}
