Fix 4 typos in lib/Analysis/

[loverszhaokai]

Summary

Fix 4 typos:

"Intialize"       -> "Initialize"
"accessable" -> "accessible"
"modeled"     ->  "modelled"

[delesley]

Looks good for the thread safety stuff.

[krememek]

Looks fine in UninitializedValues.

lib/Analysis/ThreadSafetyCommon.cpp

for (auto *Pm : Parms) {
     til::SExpr *Ld = new (Arena) til::Load(Lp);
     til::SExpr *V  = addStatement(Ld, nullptr, Pm);
     addVarDecl(Pm, V);
   }
 }
 
 
 void SExprBuilder::enterCFGBlock(const CFGBlock *B) {
-  // Intialize TIL basic block and add it to the CFG.
+  // Initialize TIL basic block and add it to the CFG.
   CurrentBB = lookupBlock(B);
   CurrentBB->reservePredecessors(B->pred_size());
   Scfg->add(CurrentBB);
 
   CurrentBlockInfo = &BBInfo[B->getBlockID()];
 
   // CurrentLVarMap is moved to ExitMap on block exit.
   // FIXME: the entry block will hold function parameters.

lib/Analysis/ThreadSafetyTIL.cpp

 // Performs a reverse topological traversal, starting from the exit block and
 // following back-edges.  The dominator is serialized before any predecessors,
 // which guarantees that all blocks are serialized after their dominator and
 // before their post-dominator (because it's a reverse topological traversal).
 // ID should be initially set to 0.
 //
 // This sort assumes that (1) dominators have been computed, (2) there are no
 // critical edges, and (3) the entry block is reachable from the exit block
-// and no blocks are accessable via traversal of back-edges from the exit that
-// weren't accessable via forward edges from the entry.
+// and no blocks are accessible via traversal of back-edges from the exit that
+// weren't accessible via forward edges from the entry.
 int BasicBlock::topologicalFinalSort(SimpleArray<BasicBlock*>& Blocks, int ID) {
   // Visited is assumed to have been set by the topologicalSort.  This pass
   // assumes !Visited means that we've visited this node before.
   if (!Visited) return ID;
   Visited = false;
   if (DominatorNode.Parent)
     ID = DominatorNode.Parent->topologicalFinalSort(Blocks, ID);
   for (auto *Pred : Predecessors)

lib/Analysis/UninitializedValues.cpp

if (VD && isTrackedVar(VD)) {
         vals[VD] = Uninitialized;
       }
     }
   }
 }
 
 void TransferFunctions::VisitObjCMessageExpr(ObjCMessageExpr *ME) {
   // If the Objective-C message expression is an implicit no-return that
-  // is not modeled in the CFG, set the tracked dataflow values to Unknown.
+  // is not modelled in the CFG, set the tracked dataflow values to Unknown.
   if (objCNoRet.isImplicitNoReturn(ME)) {
     vals.setAllScratchValues(Unknown);
   }
 }
 
 //------------------------------------------------------------------------====//
 // High-level "driver" logic for uninitialized values analysis.
 //====------------------------------------------------------------------------//