Vendor import of llvm-project main llvmorg-15-init-15358-g53dc0f107877.vendor/llvm-project/llvmorg-15-init-15358-g53dc0f107877

1 files changed, 16 insertions, 14 deletions

diff --git a/llvm/lib/Transforms/Scalar/GVNSink.cpp b/llvm/lib/Transforms/Scalar/GVNSink.cpp
index e612a82fc89a..720b8e71fd56 100644
--- a/llvm/lib/Transforms/Scalar/GVNSink.cpp
+++ b/llvm/lib/Transforms/Scalar/GVNSink.cpp
@@ -35,7 +35,6 @@
 
 #include "llvm/ADT/ArrayRef.h"
 #include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/DenseMapInfo.h"
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/ADT/Hashing.h"
 #include "llvm/ADT/None.h"
@@ -45,7 +44,6 @@
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
-#include "llvm/ADT/StringExtras.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/IR/BasicBlock.h"
 #include "llvm/IR/CFG.h"
@@ -383,6 +381,8 @@ public:
   }
 };
 
+using BasicBlocksSet = SmallPtrSet<const BasicBlock *, 32>;
+
 class ValueTable {
   DenseMap<Value *, uint32_t> ValueNumbering;
   DenseMap<GVNExpression::Expression *, uint32_t> ExpressionNumbering;
@@ -390,6 +390,7 @@ class ValueTable {
   BumpPtrAllocator Allocator;
   ArrayRecycler<Value *> Recycler;
   uint32_t nextValueNumber = 1;
+  BasicBlocksSet ReachableBBs;
 
   /// Create an expression for I based on its opcode and its uses. If I
   /// touches or reads memory, the expression is also based upon its memory
@@ -421,6 +422,11 @@ class ValueTable {
 public:
   ValueTable() = default;
 
+  /// Set basic blocks reachable from entry block.
+  void setReachableBBs(const BasicBlocksSet &ReachableBBs) {
+    this->ReachableBBs = ReachableBBs;
+  }
+
   /// Returns the value number for the specified value, assigning
   /// it a new number if it did not have one before.
   uint32_t lookupOrAdd(Value *V) {
@@ -434,6 +440,9 @@ public:
     }
 
     Instruction *I = cast<Instruction>(V);
+    if (!ReachableBBs.contains(I->getParent()))
+      return ~0U;
+
     InstructionUseExpr *exp = nullptr;
     switch (I->getOpcode()) {
     case Instruction::Load:
@@ -570,6 +579,7 @@ public:
 
     unsigned NumSunk = 0;
     ReversePostOrderTraversal<Function*> RPOT(&F);
+    VN.setReachableBBs(BasicBlocksSet(RPOT.begin(), RPOT.end()));
     for (auto *N : RPOT)
       NumSunk += sinkBB(N);
 
@@ -648,12 +658,7 @@ Optional<SinkingInstructionCandidate> GVNSink::analyzeInstructionForSinking(
     VNums[N]++;
   }
   unsigned VNumToSink =
-      std::max_element(VNums.begin(), VNums.end(),
-                       [](const std::pair<uint32_t, unsigned> &I,
-                          const std::pair<uint32_t, unsigned> &J) {
-                         return I.second < J.second;
-                       })
-          ->first;
+      std::max_element(VNums.begin(), VNums.end(), llvm::less_second())->first;
 
   if (VNums[VNumToSink] == 1)
     // Can't sink anything!
@@ -776,12 +781,9 @@ unsigned GVNSink::sinkBB(BasicBlock *BBEnd) {
 
   unsigned NumOrigPreds = Preds.size();
   // We can only sink instructions through unconditional branches.
-  for (auto I = Preds.begin(); I != Preds.end();) {
-    if ((*I)->getTerminator()->getNumSuccessors() != 1)
-      I = Preds.erase(I);
-    else
-      ++I;
-  }
+  llvm::erase_if(Preds, [](BasicBlock *BB) {
+    return BB->getTerminator()->getNumSuccessors() != 1;
+  });
 
   LockstepReverseIterator LRI(Preds);
   SmallVector<SinkingInstructionCandidate, 4> Candidates;