[PM] Pull the analyses used for another utility routine into its API

rather than relying on the pass object.

This one is a bit annoying, but will pay off. First, supporting this one
will make the next one much easier, and for utilities like LoopSimplify,
this is moving them (slowly) closer to not having to pass the pass
object around throughout their APIs.

llvm-svn: 226396

1 files changed, 53 insertions, 43 deletions

diff --git a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
index 2fb5461..c680788 100644
--- a/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
+++ b/llvm/lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -312,46 +312,46 @@ BasicBlock *llvm::SplitBlock(BasicBlock *Old, Instruction *SplitPt,
 /// analysis information.
 static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
                                       ArrayRef<BasicBlock *> Preds,
-                                      Pass *P, bool &HasLoopExit) {
-  if (!P) return;
+                                      DominatorTree *DT, LoopInfo *LI,
+                                      bool PreserveLCSSA, bool &HasLoopExit) {
+  // Update dominator tree if available.
+  if (DT)
+    DT->splitBlock(NewBB);
 
-  auto *LIWP = P->getAnalysisIfAvailable<LoopInfoWrapperPass>();
-  LoopInfo *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
-  Loop *L = LI ? LI->getLoopFor(OldBB) : nullptr;
+  // The rest of the logic is only relevant for updating the loop structures.
+  if (!LI)
+    return;
+
+  Loop *L = LI->getLoopFor(OldBB);
 
   // If we need to preserve loop analyses, collect some information about how
   // this split will affect loops.
   bool IsLoopEntry = !!L;
   bool SplitMakesNewLoopHeader = false;
-  if (LI) {
-    bool PreserveLCSSA = P->mustPreserveAnalysisID(LCSSAID);
-    for (ArrayRef<BasicBlock*>::iterator
-           i = Preds.begin(), e = Preds.end(); i != e; ++i) {
-      BasicBlock *Pred = *i;
-
-      // If we need to preserve LCSSA, determine if any of the preds is a loop
-      // exit.
-      if (PreserveLCSSA)
-        if (Loop *PL = LI->getLoopFor(Pred))
-          if (!PL->contains(OldBB))
-            HasLoopExit = true;
-
-      // If we need to preserve LoopInfo, note whether any of the preds crosses
-      // an interesting loop boundary.
-      if (!L) continue;
-      if (L->contains(Pred))
-        IsLoopEntry = false;
-      else
-        SplitMakesNewLoopHeader = true;
-    }
+  for (ArrayRef<BasicBlock *>::iterator i = Preds.begin(), e = Preds.end();
+       i != e; ++i) {
+    BasicBlock *Pred = *i;
+
+    // If we need to preserve LCSSA, determine if any of the preds is a loop
+    // exit.
+    if (PreserveLCSSA)
+      if (Loop *PL = LI->getLoopFor(Pred))
+        if (!PL->contains(OldBB))
+          HasLoopExit = true;
+
+    // If we need to preserve LoopInfo, note whether any of the preds crosses
+    // an interesting loop boundary.
+    if (!L)
+      continue;
+    if (L->contains(Pred))
+      IsLoopEntry = false;
+    else
+      SplitMakesNewLoopHeader = true;
   }
 
-  // Update dominator tree if available.
-  if (DominatorTreeWrapperPass *DTWP =
-          P->getAnalysisIfAvailable<DominatorTreeWrapperPass>())
-    DTWP->getDomTree().splitBlock(NewBB);
-
-  if (!L) return;
+  // Unless we have a loop for OldBB, nothing else to do here.
+  if (!L)
+    return;
 
   if (IsLoopEntry) {
     // Add the new block to the nearest enclosing loop (and not an adjacent
@@ -388,10 +388,9 @@ static void UpdateAnalysisInformation(BasicBlock *OldBB, BasicBlock *NewBB,
 /// UpdatePHINodes - Update the PHI nodes in OrigBB to include the values coming
 /// from NewBB. This also updates AliasAnalysis, if available.
 static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
-                           ArrayRef<BasicBlock*> Preds, BranchInst *BI,
-                           Pass *P, bool HasLoopExit) {
+                           ArrayRef<BasicBlock *> Preds, BranchInst *BI,
+                           AliasAnalysis *AA, bool HasLoopExit) {
   // Otherwise, create a new PHI node in NewBB for each PHI node in OrigBB.
-  AliasAnalysis *AA = P ? P->getAnalysisIfAvailable<AliasAnalysis>() : nullptr;
   SmallPtrSet<BasicBlock *, 16> PredSet(Preds.begin(), Preds.end());
   for (BasicBlock::iterator I = OrigBB->begin(); isa<PHINode>(I); ) {
     PHINode *PN = cast<PHINode>(I++);
@@ -468,8 +467,10 @@ static void UpdatePHINodes(BasicBlock *OrigBB, BasicBlock *NewBB,
 /// of the edges being split is an exit of a loop with other exits).
 ///
 BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB,
-                                         ArrayRef<BasicBlock*> Preds,
-                                         const char *Suffix, Pass *P) {
+                                         ArrayRef<BasicBlock *> Preds,
+                                         const char *Suffix, AliasAnalysis *AA,
+                                         DominatorTree *DT, LoopInfo *LI,
+                                         bool PreserveLCSSA) {
   // Create new basic block, insert right before the original block.
   BasicBlock *NewBB = BasicBlock::Create(BB->getContext(), BB->getName()+Suffix,
                                          BB->getParent(), BB);
@@ -500,10 +501,11 @@ BasicBlock *llvm::SplitBlockPredecessors(BasicBlock *BB,
 
   // Update DominatorTree, LoopInfo, and LCCSA analysis information.
   bool HasLoopExit = false;
-  UpdateAnalysisInformation(BB, NewBB, Preds, P, HasLoopExit);
+  UpdateAnalysisInformation(BB, NewBB, Preds, DT, LI, PreserveLCSSA,
+                            HasLoopExit);
 
   // Update the PHI nodes in BB with the values coming from NewBB.
-  UpdatePHINodes(BB, NewBB, Preds, BI, P, HasLoopExit);
+  UpdatePHINodes(BB, NewBB, Preds, BI, AA, HasLoopExit);
   return NewBB;
 }
 
@@ -548,11 +550,18 @@ void llvm::SplitLandingPadPredecessors(BasicBlock *OrigBB,
   }
 
   // Update DominatorTree, LoopInfo, and LCCSA analysis information.
+  auto *DTWP = P->getAnalysisIfAvailable<DominatorTreeWrapperPass>();
+  auto *DT = DTWP ? &DTWP->getDomTree() : nullptr;
+  auto *LIWP = P->getAnalysisIfAvailable<LoopInfoWrapperPass>();
+  auto *LI = LIWP ? &LIWP->getLoopInfo() : nullptr;
+  bool PreserveLCSSA = P->mustPreserveAnalysisID(LCSSAID);
   bool HasLoopExit = false;
-  UpdateAnalysisInformation(OrigBB, NewBB1, Preds, P, HasLoopExit);
+  UpdateAnalysisInformation(OrigBB, NewBB1, Preds, DT, LI, PreserveLCSSA,
+                            HasLoopExit);
 
   // Update the PHI nodes in OrigBB with the values coming from NewBB1.
-  UpdatePHINodes(OrigBB, NewBB1, Preds, BI1, P, HasLoopExit);
+  AliasAnalysis *AA = P ? P->getAnalysisIfAvailable<AliasAnalysis>() : nullptr;
+  UpdatePHINodes(OrigBB, NewBB1, Preds, BI1, AA, HasLoopExit);
 
   // Move the remaining edges from OrigBB to point to NewBB2.
   SmallVector<BasicBlock*, 8> NewBB2Preds;
@@ -584,10 +593,11 @@ void llvm::SplitLandingPadPredecessors(BasicBlock *OrigBB,
 
     // Update DominatorTree, LoopInfo, and LCCSA analysis information.
     HasLoopExit = false;
-    UpdateAnalysisInformation(OrigBB, NewBB2, NewBB2Preds, P, HasLoopExit);
+    UpdateAnalysisInformation(OrigBB, NewBB2, NewBB2Preds, DT, LI,
+                              PreserveLCSSA, HasLoopExit);
 
     // Update the PHI nodes in OrigBB with the values coming from NewBB2.
-    UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, P, HasLoopExit);
+    UpdatePHINodes(OrigBB, NewBB2, NewBB2Preds, BI2, AA, HasLoopExit);
   }
 
   LandingPadInst *LPad = OrigBB->getLandingPadInst();