Temporarily Revert "[Attributor] Liveness analysis." as it's breaking the build.

This reverts commit 9285295f75a231dc446fa7cbc10a0a391b3434a5.

llvm-svn: 366737

diff --git a/llvm/include/llvm/Transforms/IPO/Attributor.h b/llvm/include/llvm/Transforms/IPO/Attributor.h
index 089df8e..4816d1b 100644 (file)
--- a/llvm/include/llvm/Transforms/IPO/Attributor.h
+++ b/llvm/include/llvm/Transforms/IPO/Attributor.h
@@ -805,46 +805,6 @@ struct AANoAlias : public AbstractAttribute {
   static constexpr Attribute::AttrKind ID = Attribute::NoAlias;
 };
 
-/// An AbstractAttribute for noreturn.
-struct AANoReturn : public AbstractAttribute {
-
-  /// See AbstractAttribute::AbstractAttribute(...).
-  AANoReturn(Value &V, InformationCache &InfoCache)
-      : AbstractAttribute(V, InfoCache) {}
-
-  /// Return true if the underlying object is known to never return.
-  virtual bool isKnownNoReturn() const = 0;
-
-  /// Return true if the underlying object is assumed to never return.
-  virtual bool isAssumedNoReturn() const = 0;
-
-  /// See AbstractAttribute::getAttrKind()
-  Attribute::AttrKind getAttrKind() const override { return ID; }
-
-  /// The identifier used by the Attributor for this class of attributes.
-  static constexpr Attribute::AttrKind ID = Attribute::NoReturn;
-};
-
-/// An abstract interface for liveness abstract attribute.
-struct AAIsDead : public AbstractAttribute {
-
-  /// See AbstractAttribute::AbstractAttribute(...).
-  AAIsDead(Value &V, InformationCache &InfoCache)
-      : AbstractAttribute(V, InfoCache) {}
-
-  /// See AbstractAttribute::getAttrKind()
-  Attribute::AttrKind getAttrKind() const override { return ID; }
-
-  static constexpr Attribute::AttrKind ID =
-      Attribute::AttrKind(Attribute::EndAttrKinds + 1);
-
-  /// Returns true if \p BB is assumed dead.
-  virtual bool isAssumedDead(BasicBlock *BB) const = 0;
-
-  /// Returns true if \p BB is known dead.
-  virtual bool isKnownDead(BasicBlock *BB) const = 0;
-};
-
 } // end namespace llvm
 
 #endif // LLVM_TRANSFORMS_IPO_FUNCTIONATTRS_H

diff --git a/llvm/include/llvm/Transforms/Utils/Local.h b/llvm/include/llvm/Transforms/Utils/Local.h
index 5e252fe..ff516f2 100644 (file)
--- a/llvm/include/llvm/Transforms/Utils/Local.h
+++ b/llvm/include/llvm/Transforms/Utils/Local.h
@@ -271,9 +271,6 @@ inline unsigned getKnownAlignment(Value *V, const DataLayout &DL,
   return getOrEnforceKnownAlignment(V, 0, DL, CxtI, AC, DT);
 }
 
-/// This function converts the specified invoek into a normall call.
-void changeToCall(InvokeInst *II, DomTreeUpdater *DTU = nullptr);
-
 ///===---------------------------------------------------------------------===//
 ///  Dbg Intrinsic utilities
 ///

diff --git a/llvm/lib/Transforms/IPO/Attributor.cpp b/llvm/lib/Transforms/IPO/Attributor.cpp
index f4e2ed4..fa5dbc2 100644 (file)
--- a/llvm/lib/Transforms/IPO/Attributor.cpp
+++ b/llvm/lib/Transforms/IPO/Attributor.cpp
@@ -16,7 +16,6 @@
 #include "llvm/Transforms/IPO/Attributor.h"
 
 #include "llvm/ADT/DepthFirstIterator.h"
-#include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/SmallVector.h"
@@ -32,9 +31,6 @@
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
-#include "llvm/Transforms/Utils/BasicBlockUtils.h"
-#include "llvm/Transforms/Utils/Local.h"
-
 #include <cassert>
 
 using namespace llvm;
@@ -1415,173 +1411,6 @@ ChangeStatus AANoAliasReturned::updateImpl(Attributor &A) {
   return ChangeStatus::UNCHANGED;
 }
 
-/// -------------------AAIsDead Function Attribute-----------------------
-
-struct AAIsDeadFunction : AAIsDead, BooleanState {
-
-  AAIsDeadFunction(Function &F, InformationCache &InfoCache)
-      : AAIsDead(F, InfoCache) {}
-
-  /// See AbstractAttribute::getState()
-  /// {
-  AbstractState &getState() override { return *this; }
-  const AbstractState &getState() const override { return *this; }
-  /// }
-
-  /// See AbstractAttribute::getManifestPosition().
-  ManifestPosition getManifestPosition() const override { return MP_FUNCTION; }
-
-  void initialize(Attributor &A) override {
-    Function &F = getAnchorScope();
-
-    ToBeExploredPaths.insert(&(F.getEntryBlock().front()));
-    AssumedLiveBlocks.insert(&(F.getEntryBlock()));
-    for (size_t i = 0; i < ToBeExploredPaths.size(); ++i)
-      explorePath(A, ToBeExploredPaths[i]);
-  }
-
-  /// Explores new instructions starting from \p I. If instruction is dead, stop
-  /// and return true if it discovered a new instruction.
-  bool explorePath(Attributor &A, Instruction *I);
-
-  const std::string getAsStr() const override {
-    return "LiveBBs(" + std::to_string(AssumedLiveBlocks.size()) + "/" +
-           std::to_string(getAnchorScope().size()) + ")";
-  }
-
-  /// See AbstractAttribute::manifest(...).
-  ChangeStatus manifest(Attributor &A) override {
-    assert(getState().isValidState() &&
-           "Attempted to manifest an invalid state!");
-
-    ChangeStatus HasChanged = ChangeStatus::UNCHANGED;
-
-    for (Instruction *I : NoReturnCalls) {
-      BasicBlock *BB = I->getParent();
-
-      /// Invoke is replaced with a call and unreachable is placed after it.
-      if (auto *II = dyn_cast<InvokeInst>(I)) {
-        changeToCall(II);
-        changeToUnreachable(BB->getTerminator(), /* UseLLVMTrap */ false);
-        LLVM_DEBUG(dbgs() << "[AAIsDead] Replaced invoke with call inst\n");
-        continue;
-      }
-
-      SplitBlock(BB, I->getNextNode());
-      changeToUnreachable(BB->getTerminator(), /* UseLLVMTrap */ false);
-      HasChanged = ChangeStatus::CHANGED;
-    }
-
-    return HasChanged;
-  }
-
-  /// See AbstractAttribute::updateImpl(...).
-  ChangeStatus updateImpl(Attributor &A) override;
-
-  /// See AAIsDead::isAssumedDead().
-  bool isAssumedDead(BasicBlock *BB) const override {
-    if (!getAssumed())
-      return false;
-    return !AssumedLiveBlocks.count(BB);
-  }
-
-  /// See AAIsDead::isKnownDead().
-  bool isKnownDead(BasicBlock *BB) const override {
-    if (!getKnown())
-      return false;
-    return !AssumedLiveBlocks.count(BB);
-  }
-
-  /// Collection of to be explored paths.
-  SmallSetVector<Instruction *, 8> ToBeExploredPaths;
-
-  /// Collection of all assumed live BasicBlocks.
-  DenseSet<BasicBlock *> AssumedLiveBlocks;
-
-  /// Collection of calls with noreturn attribute, assumed or knwon.
-  SmallSetVector<Instruction *, 4> NoReturnCalls;
-};
-
-bool AAIsDeadFunction::explorePath(Attributor &A, Instruction *I) {
-  BasicBlock *BB = I->getParent();
-
-  while (I) {
-    ImmutableCallSite ICS(I);
-
-    if (ICS) {
-      auto *NoReturnAA = A.getAAFor<AANoReturn>(*this, *I);
-
-      if (NoReturnAA && NoReturnAA->isAssumedNoReturn()) {
-        if (!NoReturnCalls.insert(I))
-          // If I is already in the NoReturnCalls set, then it stayed noreturn
-          // and we didn't discover any new instructions.
-          return false;
-
-        // Discovered new noreturn call, return true to indicate that I is not
-        // noreturn anymore and should be deleted from NoReturnCalls.
-        return true;
-      }
-
-      if (ICS.hasFnAttr(Attribute::NoReturn)) {
-        if(!NoReturnCalls.insert(I))
-          return false;
-
-        return true;
-      }
-    }
-
-    I = I->getNextNode();
-  }
-
-  // get new paths (reachable blocks).
-  for (BasicBlock *SuccBB : successors(BB)) {
-    Instruction *Inst = &(SuccBB->front());
-    AssumedLiveBlocks.insert(SuccBB);
-    ToBeExploredPaths.insert(Inst);
-  }
-
-  return true;
-}
-
-ChangeStatus AAIsDeadFunction::updateImpl(Attributor &A) {
-  Function &F = getAnchorScope();
-
-  // Temporary collection to iterate over existing noreturn instructions. This
-  // will alow easier modification of NoReturnCalls collection
-  SmallVector<Instruction *, 8> NoReturnChanged;
-  ChangeStatus Status = ChangeStatus::UNCHANGED;
-
-  for (Instruction *I : NoReturnCalls)
-    NoReturnChanged.push_back(I);
-
-  for (Instruction *I : NoReturnChanged) {
-    size_t Size = ToBeExploredPaths.size();
-
-    // Still noreturn.
-    if (!explorePath(A, I))
-      continue;
-
-    NoReturnCalls.remove(I);
-
-    // No new paths.
-    if (Size == ToBeExploredPaths.size())
-      continue;
-
-    // At least one new path.
-    Status = ChangeStatus::CHANGED;
-
-    // explore new paths.
-    while (Size != ToBeExploredPaths.size())
-      explorePath(A, ToBeExploredPaths[Size++]);
-  }
-
-  LLVM_DEBUG(dbgs() << "[AAIsDead] AssumedLiveBlocks: "
-                    << AssumedLiveBlocks.size()
-                    << "Total number of blocks: " << F.size() << "\n");
-
-  return Status;
-}
-
 /// ----------------------------------------------------------------------------
 ///                               Attributor
 /// ----------------------------------------------------------------------------
@@ -1798,9 +1627,6 @@ void Attributor::identifyDefaultAbstractAttributes(
   // Every function might be "will-return".
   registerAA(*new AAWillReturnFunction(F, InfoCache));
 
-  // Check for dead BasicBlocks in every function.
-  registerAA(*new AAIsDeadFunction(F, InfoCache));
-
   // Walk all instructions to find more attribute opportunities and also
   // interesting instructions that might be queried by abstract attributes
   // during their initialization or update.

diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 62c7dd6..be16054 100644 (file)
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -1964,7 +1964,7 @@ unsigned llvm::changeToUnreachable(Instruction *I, bool UseLLVMTrap,
 }
 
 /// changeToCall - Convert the specified invoke into a normal call.
-void llvm::changeToCall(InvokeInst *II, DomTreeUpdater *DTU = nullptr) {
+static void changeToCall(InvokeInst *II, DomTreeUpdater *DTU = nullptr) {
   SmallVector<Value*, 8> Args(II->arg_begin(), II->arg_end());
   SmallVector<OperandBundleDef, 1> OpBundles;
   II->getOperandBundlesAsDefs(OpBundles);

diff --git a/llvm/test/Transforms/FunctionAttrs/liveness.ll b/llvm/test/Transforms/FunctionAttrs/liveness.ll
deleted file mode 100644 (file)
index 1de005d..0000000
--- a/llvm/test/Transforms/FunctionAttrs/liveness.ll
+++ /dev/null
@@ -1,250 +0,0 @@
-; RUN: opt -attributor --attributor-disable=false -S < %s | FileCheck %s
-
-declare void @no_return_call() noreturn
-
-declare void @normal_call()
-
-declare i32 @foo()
-
-declare i32 @foo_noreturn() noreturn
-
-declare i32 @bar()
-
-; TEST 1: cond.true is dead, but cond.end is not, since cond.false is live
-
-; This is just an example. For example we can put a sync call in a
-; dead block and check if it is deduced.
-
-define i32 @dead_block_present(i32 %a) #0 {
-entry:
-  %cmp = icmp eq i32 %a, 0
-  br i1 %cmp, label %cond.true, label %cond.false
-
-cond.true:                                        ; preds = %entry
-  call void @no_return_call()
-  ; CHECK: call void @no_return_call()
-  ; CHECK-NEXT: unreachable
-  %call = call i32 @foo()
-  br label %cond.end
-
-cond.false:                                       ; preds = %entry
-  call void @normal_call()
-  %call1 = call i32 @bar()
-  br label %cond.end
-
-cond.end:                                         ; preds = %cond.false, %cond.true
-  %cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
-  ret i32 %cond
-}
-
-; TEST 2: both cond.true and cond.false are dead, therfore cond.end is dead as well.
-
-define i32 @all_dead(i32 %a) #0 {
-entry:
-  %cmp = icmp eq i32 %a, 0
-  br i1 %cmp, label %cond.true, label %cond.false
-
-cond.true:                                        ; preds = %entry
-  call void @no_return_call()
-  ; CHECK: call void @no_return_call()
-  ; CHECK-NEXT: unreachable
-  %call = call i32 @foo()
-  br label %cond.end
-
-cond.false:                                       ; preds = %entry
-  call void @no_return_call()
-  ; CHECK: call void @no_return_call()
-  ; CHECK-NEXT: unreachable
-  %call1 = call i32 @bar()
-  br label %cond.end
-
-cond.end:                                         ; preds = %cond.false, %cond.true
-  %cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
-  ret i32 %cond
-}
-
-declare i32 @__gxx_personality_v0(...)
-
-; TEST 3: All blocks are live.
-
-; CHECK: define i32 @all_live(i32 %a)
-define i32 @all_live(i32 %a) #0 {
-entry:
-  %cmp = icmp eq i32 %a, 0
-  br i1 %cmp, label %cond.true, label %cond.false
-
-cond.true:                                        ; preds = %entry
-  call void @normal_call()
-  %call = call i32 @foo_noreturn()
-  br label %cond.end
-
-cond.false:                                       ; preds = %entry
-  call void @normal_call()
-  %call1 = call i32 @bar()
-  br label %cond.end
-
-cond.end:                                         ; preds = %cond.false, %cond.true
-  %cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
-  ret i32 %cond
-}
-
-; TEST 4 noreturn invoke instruction replaced by a call and an unreachable instruction
-; put after it.
-
-; CHECK: define i32 @invoke_noreturn(i32 %a)
-define i32 @invoke_noreturn(i32 %a) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
-entry:
-  %cmp = icmp eq i32 %a, 0
-  br i1 %cmp, label %cond.true, label %cond.false
-
-cond.true:                                        ; preds = %entry
-  call void @normal_call()
-  %call = invoke i32 @foo_noreturn() to label %continue
-            unwind label %cleanup
-  ; CHECK: call i32 @foo_noreturn()
-  ; CHECK-NEXT unreachable
-
-cond.false:                                       ; preds = %entry
-  call void @normal_call()
-  %call1 = call i32 @bar()
-  br label %cond.end
-
-cond.end:                                         ; preds = %cond.false, %continue
-  %cond = phi i32 [ %call, %continue ], [ %call1, %cond.false ]
-  ret i32 %cond
-
-continue:
-  br label %cond.end
-
-cleanup:
-  %res = landingpad { i8*, i32 }
-  catch i8* null
-  ret i32 0
-}
-
-; TEST 5: Undefined behvior, taken from LangRef.
-; FIXME: Should be able to detect undefined behavior.
-
-; CHECK define @ub(i32)
-define void @ub(i32* ) {
-  %poison = sub nuw i32 0, 1           ; Results in a poison value.
-  %still_poison = and i32 %poison, 0   ; 0, but also poison.
-  %poison_yet_again = getelementptr i32, i32* %0, i32 %still_poison
-  store i32 0, i32* %poison_yet_again  ; Undefined behavior due to store to poison.
-  ret void
-}
-
-define void @inf_loop() #0 {
-entry:
-  br label %while.body
-
-while.body:                                       ; preds = %entry, %while.body
-  br label %while.body
-}
-
-; TEST 6: Infinite loop.
-; FIXME: Detect infloops, and mark affected blocks dead.
-
-define i32 @test5(i32, i32) #0 {
-  %3 = icmp sgt i32 %0, %1
-  br i1 %3, label %cond.if, label %cond.elseif
-
-cond.if:                                                ; preds = %2
-  %4 = tail call i32 @bar()
-  br label %cond.end
-
-cond.elseif:                                                ; preds = %2
-  call void @inf_loop()
-  %5 = icmp slt i32 %0, %1
-  br i1 %5, label %cond.end, label %cond.else
-
-cond.else:                                                ; preds = %cond.elseif
-  %6 = tail call i32 @foo()
-  br label %cond.end
-
-cond.end:                                               ; preds = %cond.if, %cond.else, %cond.elseif
-  %7 = phi i32 [ %1, %cond.elseif ], [ 0, %cond.else ], [ 0, %cond.if ]
-  ret i32 %7
-}
-
-define void @rec() #0 {
-entry:
-  call void @rec()
-  ret void
-}
-
-; TEST 7: Recursion
-; FIXME: everything after first block should be marked dead
-; and unreachable should be put after call to @rec().
-
-define i32 @test6(i32, i32) #0 {
-  call void @rec()
-  %3 = icmp sgt i32 %0, %1
-  br i1 %3, label %cond.if, label %cond.elseif
-
-cond.if:                                                ; preds = %2
-  %4 = tail call i32 @bar()
-  br label %cond.end
-
-cond.elseif:                                                ; preds = %2
-  call void @rec()
-  %5 = icmp slt i32 %0, %1
-  br i1 %5, label %cond.end, label %cond.else
-
-cond.else:                                                ; preds = %cond.elseif
-  %6 = tail call i32 @foo()
-  br label %cond.end
-
-cond.end:                                               ; preds = %cond.if, %cond.else, %cond.elseif
-  %7 = phi i32 [ %1, %cond.elseif ], [ 0, %cond.else ], [ 0, %cond.if ]
-  ret i32 %7
-}
-; TEST 8: Recursion
-; FIXME: contains recursive call to itself in cond.elseif block
-
-define i32 @test7(i32, i32) #0 {
-  %3 = icmp sgt i32 %0, %1
-  br i1 %3, label %cond.if, label %cond.elseif
-
-cond.if:                                                ; preds = %2
-  %4 = tail call i32 @bar()
-  br label %cond.end
-
-cond.elseif:                                                ; preds = %2
-  %5 = tail call i32 @test7(i32 %0, i32 %1)
-  %6 = icmp slt i32 %0, %1
-  br i1 %6, label %cond.end, label %cond.else
-
-cond.else:                                                ; preds = %cond.elseif
-  %7 = tail call i32 @foo()
-  br label %cond.end
-
-cond.end:                                               ; preds = %cond.if, %cond.else, %cond.elseif
-  %8 = phi i32 [ %1, %cond.elseif ], [ 0, %cond.else ], [ 0, %cond.if ]
-  ret i32 %8
-}
-
-; TEST 9: Only first block is live.
-
-define i32 @first_block_no_return(i32 %a) #0 {
-entry:
-  call void @no_return_call()
-  ; CHECK: call void @no_return_call()
-  ; CHECK-NEXT: unreachable
-  %cmp = icmp eq i32 %a, 0
-  br i1 %cmp, label %cond.true, label %cond.false
-
-cond.true:                                        ; preds = %entry
-  call void @normal_call()
-  %call = call i32 @foo()
-  br label %cond.end
-
-cond.false:                                       ; preds = %entry
-  call void @normal_call()
-  %call1 = call i32 @bar()
-  br label %cond.end
-
-cond.end:                                         ; preds = %cond.false, %cond.true
-  %cond = phi i32 [ %call, %cond.true ], [ %call1, %cond.false ]
-  ret i32 %cond
-}