1 files changed, 2 insertions, 38 deletions

diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index e4ba70d..5af6c96 100644
--- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -27,7 +27,6 @@
 #include "llvm/Analysis/MemorySSA.h"
 #include "llvm/Analysis/MemorySSAUpdater.h"
 #include "llvm/Analysis/MustExecute.h"
-#include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/Analysis/ScalarEvolution.h"
 #include "llvm/Analysis/TargetTransformInfo.h"
 #include "llvm/Analysis/ValueTracking.h"
@@ -3611,8 +3610,7 @@ static bool unswitchLoop(Loop &L, DominatorTree &DT, LoopInfo &LI,
                          AssumptionCache &AC, AAResults &AA,
                          TargetTransformInfo &TTI, bool Trivial,
                          bool NonTrivial, ScalarEvolution *SE,
-                         MemorySSAUpdater *MSSAU, ProfileSummaryInfo *PSI,
-                         BlockFrequencyInfo *BFI, LPMUpdater &LoopUpdater) {
+                         MemorySSAUpdater *MSSAU, LPMUpdater &LoopUpdater) {
   assert(L.isRecursivelyLCSSAForm(DT, LI) &&
          "Loops must be in LCSSA form before unswitching.");
 
@@ -3652,35 +3650,6 @@ static bool unswitchLoop(Loop &L, DominatorTree &DT, LoopInfo &LI,
   if (F->hasOptSize())
     return false;
 
-  // Returns true if Loop L's loop nest is cold, i.e. if the headers of L,
-  // of the loops L is nested in, and of the loops nested in L are all cold.
-  auto IsLoopNestCold = [&](const Loop *L) {
-    // Check L and all of its parent loops.
-    auto *Parent = L;
-    while (Parent) {
-      if (!PSI->isColdBlock(Parent->getHeader(), BFI))
-        return false;
-      Parent = Parent->getParentLoop();
-    }
-    // Next check all loops nested within L.
-    SmallVector<const Loop *, 4> Worklist;
-    llvm::append_range(Worklist, L->getSubLoops());
-    while (!Worklist.empty()) {
-      auto *CurLoop = Worklist.pop_back_val();
-      if (!PSI->isColdBlock(CurLoop->getHeader(), BFI))
-        return false;
-      llvm::append_range(Worklist, CurLoop->getSubLoops());
-    }
-    return true;
-  };
-
-  // Skip cold loops in cold loop nests, as unswitching them brings little
-  // benefit but increases the code size
-  if (PSI && PSI->hasProfileSummary() && BFI && IsLoopNestCold(&L)) {
-    LLVM_DEBUG(dbgs() << " Skip cold loop: " << L << "\n");
-    return false;
-  }
-
   // Perform legality checks.
   if (!isSafeForNoNTrivialUnswitching(L, LI))
     return false;
@@ -3705,11 +3674,6 @@ PreservedAnalyses SimpleLoopUnswitchPass::run(Loop &L, LoopAnalysisManager &AM,
                                               LPMUpdater &U) {
   Function &F = *L.getHeader()->getParent();
   (void)F;
-  ProfileSummaryInfo *PSI = nullptr;
-  if (auto OuterProxy =
-          AM.getResult<FunctionAnalysisManagerLoopProxy>(L, AR)
-              .getCachedResult<ModuleAnalysisManagerFunctionProxy>(F))
-    PSI = OuterProxy->getCachedResult<ProfileSummaryAnalysis>(*F.getParent());
   LLVM_DEBUG(dbgs() << "Unswitching loop in " << F.getName() << ": " << L
                     << "\n");
 
@@ -3720,7 +3684,7 @@ PreservedAnalyses SimpleLoopUnswitchPass::run(Loop &L, LoopAnalysisManager &AM,
       AR.MSSA->verifyMemorySSA();
   }
   if (!unswitchLoop(L, AR.DT, AR.LI, AR.AC, AR.AA, AR.TTI, Trivial, NonTrivial,
-                    &AR.SE, MSSAU ? &*MSSAU : nullptr, PSI, AR.BFI, U))
+                    &AR.SE, MSSAU ? &*MSSAU : nullptr, U))
     return PreservedAnalyses::all();
 
   if (AR.MSSA && VerifyMemorySSA)