Reimplement isPotentiallyReachable to make nocapture deduction much stronger.
Adds unit tests for it too.
Split BasicBlockUtils into an analysis-half and a transforms-half, and put the
analysis bits into a new Analysis/CFG.{h,cpp}. Promote isPotentiallyReachable
into llvm::isPotentiallyReachable and move it into Analysis/CFG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187283 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/BreakCriticalEdges.cpp b/lib/Transforms/Utils/BreakCriticalEdges.cpp
index 8513772..8f3ff96 100644
--- a/lib/Transforms/Utils/BreakCriticalEdges.cpp
+++ b/lib/Transforms/Utils/BreakCriticalEdges.cpp
@@ -19,6 +19,7 @@
#include "llvm/Transforms/Scalar.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/CFG.h"
#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/ProfileInfo.h"
@@ -84,39 +85,6 @@
// Implementation of the external critical edge manipulation functions
//===----------------------------------------------------------------------===//
-// isCriticalEdge - Return true if the specified edge is a critical edge.
-// Critical edges are edges from a block with multiple successors to a block
-// with multiple predecessors.
-//
-bool llvm::isCriticalEdge(const TerminatorInst *TI, unsigned SuccNum,
- bool AllowIdenticalEdges) {
- assert(SuccNum < TI->getNumSuccessors() && "Illegal edge specification!");
- if (TI->getNumSuccessors() == 1) return false;
-
- const BasicBlock *Dest = TI->getSuccessor(SuccNum);
- const_pred_iterator I = pred_begin(Dest), E = pred_end(Dest);
-
- // If there is more than one predecessor, this is a critical edge...
- assert(I != E && "No preds, but we have an edge to the block?");
- const BasicBlock *FirstPred = *I;
- ++I; // Skip one edge due to the incoming arc from TI.
- if (!AllowIdenticalEdges)
- return I != E;
-
- // If AllowIdenticalEdges is true, then we allow this edge to be considered
- // non-critical iff all preds come from TI's block.
- while (I != E) {
- const BasicBlock *P = *I;
- if (P != FirstPred)
- return true;
- // Note: leave this as is until no one ever compiles with either gcc 4.0.1
- // or Xcode 2. This seems to work around the pred_iterator assert in PR 2207
- E = pred_end(P);
- ++I;
- }
- return false;
-}
-
/// createPHIsForSplitLoopExit - When a loop exit edge is split, LCSSA form
/// may require new PHIs in the new exit block. This function inserts the
/// new PHIs, as needed. Preds is a list of preds inside the loop, SplitBB