[NFC] SILCombine: Use DeadEndBlocksAnalysis.

Instead of having a separately calculated version.

Author: nate-chandler

lib/SILOptimizer/SILCombiner/SILCombine.cpp

@@ -192,8 +192,8 @@ SILCombiner::SILCombiner(SILFunctionTransform *trans,
                 use->set(newValue);
                 Worklist.add(use->getUser());
               })),
-  deadEndBlocks(trans->getFunction()), MadeChange(false),
-  RemoveCondFails(removeCondFails),
+  DEBA(trans->getPassManager()->getAnalysis<DeadEndBlocksAnalysis>()), 
+  MadeChange(false), RemoveCondFails(removeCondFails),
   enableCopyPropagation(enableCopyPropagation), Iteration(0),
   Builder(*trans->getFunction(), &TrackingList),
   FuncBuilder(*trans),
@@ -354,7 +354,7 @@ void SILCombiner::canonicalizeOSSALifetimes(SILInstruction *currentInst) {
   CanonicalizeOSSALifetime canonicalizer(
       DontPruneDebugInsts,
       MaximizeLifetime_t(!parentTransform->getFunction()->shouldOptimize()),
-      parentTransform->getFunction(), NLABA, domTree, CA, deleter);
+      parentTransform->getFunction(), NLABA, DEBA, domTree, CA, deleter);
   CanonicalizeBorrowScope borrowCanonicalizer(parentTransform->getFunction(),
                                               deleter);
 
@@ -397,7 +397,7 @@ bool SILCombiner::doOneIteration(SILFunction &F, unsigned Iteration) {
   // Add reachable instructions to our worklist.
   addReachableCodeToWorklist(&*F.begin());
 
-  SILCombineCanonicalize scCanonicalize(Worklist, deadEndBlocks);
+  SILCombineCanonicalize scCanonicalize(Worklist, *DEBA->get(&F));
 
   // Process until we run out of items in our worklist.
   while (!Worklist.isEmpty()) {

lib/SILOptimizer/SILCombiner/SILCombiner.h

@@ -31,6 +31,7 @@
 #include "swift/SIL/SILVisitor.h"
 #include "swift/SILOptimizer/Analysis/BasicCalleeAnalysis.h"
 #include "swift/SILOptimizer/Analysis/ClassHierarchyAnalysis.h"
+#include "swift/SILOptimizer/Analysis/DeadEndBlocksAnalysis.h"
 #include "swift/SILOptimizer/Analysis/NonLocalAccessBlockAnalysis.h"
 #include "swift/SILOptimizer/Analysis/ProtocolConformanceAnalysis.h"
 #include "swift/SILOptimizer/OptimizerBridging.h"
@@ -83,7 +84,7 @@ class SILCombiner :
   /// A cache of "dead end blocks" through which all paths it is known that the
   /// program will terminate. This means that we are allowed to leak
   /// objects.
-  DeadEndBlocks deadEndBlocks;
+  DeadEndBlocksAnalysis *DEBA;
 
   /// Variable to track if the SILCombiner made any changes.
   bool MadeChange;