Subzero, Wasm: Link and run torture tests; bug fixes.

src/IceCfgNode.cpp

 //===- subzero/src/IceCfgNode.cpp - Basic block (node) implementation -----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 66 matching lines @@
 // have to be built up incrementally. After the CFG has been constructed, the
 // computePredecessors() pass finalizes it by creating the InEdges list.
 void CfgNode::computePredecessors() {
   for (CfgNode *Succ : OutEdges)
     Succ->InEdges.push_back(this);
 }
 
 void CfgNode::computeSuccessors() {
   OutEdges.clear();
   InEdges.clear();
+  assert(!Insts.empty());
   OutEdges = Insts.rbegin()->getTerminatorEdges();
 }
 
 // Ensure each Phi instruction in the node is consistent with respect to control
 // flow.  For each predecessor, there must be a phi argument with that label.
 // If a phi argument's label doesn't appear in the predecessor list (which can
 // happen as a result of e.g. unreachable node elimination), its value is
 // modified to be zero, to maintain consistency in liveness analysis.  This
 // allows us to remove some dead control flow without a major rework of the phi
 // instructions.  We don't check that phi arguments with the same label have the
@@ skipping 1368 matching lines @@
   auto *Instr = InstIntrinsicCall::create(
       Func, 5, Func->makeVariable(IceType_i64), RMWI64Name, Info->Info);
   Instr->addArg(AtomicRMWOp);
   Instr->addArg(Counter);
   Instr->addArg(One);
   Instr->addArg(OrderAcquireRelease);
   Insts.push_front(Instr);
 }
 
 } // end of namespace Ice