Exemplo n.º 1
0
        private static void InvokeSecondPassWasm(uint idxStart, uint idxTryLandingStart, ref EHClauseIterator clauseIter, uint idxLimit, void *shadowStack)
        {
            uint lastTryStart = 0, lastTryEnd = 0;
            // Search the clauses for one that contains the current offset.
            RhEHClauseWasm ehClause = new RhEHClauseWasm();

            for (uint curIdx = 0; clauseIter.Next(ref ehClause) && curIdx < idxLimit; curIdx++)
            {
                //
                // Skip to the starting try region.  This is used by collided unwinds and rethrows to pickup where
                // the previous dispatch left off.
                //
                if (idxStart != MaxTryRegionIdx)
                {
                    if (curIdx <= idxStart)
                    {
                        lastTryStart = ehClause._tryStartOffset;
                        lastTryEnd   = ehClause._tryEndOffset;
                        continue;
                    }

                    // Now, we continue skipping while the try region is identical to the one that invoked the
                    // previous dispatch.
                    if ((ehClause._tryStartOffset == lastTryStart) && (ehClause._tryEndOffset == lastTryEnd))
                    {
                        continue;
                    }

                    // We are done skipping. This is required to handle empty finally block markers that are used
                    // to separate runs of different try blocks with same native code offsets.
                    idxStart = MaxTryRegionIdx;
                }

                EHClauseIterator.RhEHClauseKindWasm clauseKind = ehClause._clauseKind;

                if ((clauseKind != EHClauseIterator.RhEHClauseKindWasm.RH_EH_CLAUSE_FAULT) ||
                    !ehClause.TryStartsAt(idxTryLandingStart))
                {
                    continue;
                }

                // Found a containing clause. Because of the order of the clauses, we know this is the
                // most containing.

                // N.B. -- We need to suppress GC "in-between" calls to finallys in this loop because we do
                // not have the correct next-execution point live on the stack and, therefore, may cause a GC
                // hole if we allow a GC between invocation of finally funclets (i.e. after one has returned
                // here to the dispatcher, but before the next one is invoked).  Once they are running, it's
                // fine for them to trigger a GC, obviously.
                //
                // As a result, RhpCallFinallyFunclet will set this state in the runtime upon return from the
                // funclet, and we need to reset it if/when we fall out of the loop and we know that the
                // method will no longer get any more GC callbacks.

                byte *pFinallyHandler = ehClause._handlerAddress;

                InternalCalls.RhpCallFinallyFunclet(pFinallyHandler, shadowStack);
            }
        }
Exemplo n.º 2
0
        // TODO: temporary to try things out, when working look to see how to refactor with FindFirstPassHandler
        private static bool FindFirstPassHandlerWasm(object exception, uint idxStart, uint idxTryLandingStart /* the start IL idx of the try region for the landing pad, will use in place of PC */,
                                                     void *shadowStack, void *exInfo,
                                                     ref EHClauseIterator clauseIter, out uint tryRegionIdx, out byte *pHandler)
        {
            pHandler     = (byte *)0;
            tryRegionIdx = MaxTryRegionIdx;
            uint           lastTryStart = 0, lastTryEnd = 0;
            RhEHClauseWasm ehClause = new RhEHClauseWasm();

            for (uint curIdx = 0; clauseIter.Next(ref ehClause); curIdx++)
            {
                //
                // Skip to the starting try region.  This is used by collided unwinds and rethrows to pickup where
                // the previous dispatch left off.
                //
                if (idxStart != MaxTryRegionIdx)
                {
                    if (curIdx <= idxStart)
                    {
                        lastTryStart = ehClause._tryStartOffset;
                        lastTryEnd   = ehClause._tryEndOffset;
                        continue;
                    }

                    // Now, we continue skipping while the try region is identical to the one that invoked the
                    // previous dispatch.
                    if ((ehClause._tryStartOffset == lastTryStart) && (ehClause._tryEndOffset == lastTryEnd))
                    {
                        continue;
                    }

                    // We are done skipping. This is required to handle empty finally block markers that are used
                    // to separate runs of different try blocks with same native code offsets.
                    idxStart = MaxTryRegionIdx;
                }

                EHClauseIterator.RhEHClauseKindWasm clauseKind = ehClause._clauseKind;
                if (((clauseKind != EHClauseIterator.RhEHClauseKindWasm.RH_EH_CLAUSE_TYPED) &&
                     (clauseKind != EHClauseIterator.RhEHClauseKindWasm.RH_EH_CLAUSE_FILTER)) ||
                    !ehClause.TryStartsAt(idxTryLandingStart))
                {
                    continue;
                }

                // Found a containing clause. Because of the order of the clauses, we know this is the
                // most containing.
                if (clauseKind == EHClauseIterator.RhEHClauseKindWasm.RH_EH_CLAUSE_TYPED)
                {
                    if (ShouldTypedClauseCatchThisException(exception, (EEType *)ehClause._typeSymbol))
                    {
                        pHandler     = ehClause._handlerAddress;
                        tryRegionIdx = curIdx;
                        return(true);
                    }
                }
                else
                {
                    tryRegionIdx = 0;
                    bool shouldInvokeHandler = InternalCalls.RhpCallFilterFunclet(exception, ehClause._filterAddress, shadowStack);
                    if (shouldInvokeHandler)
                    {
                        pHandler     = ehClause._handlerAddress;
                        tryRegionIdx = curIdx;
                        return(true);
                    }
                }
            }

            return(false);
        }