Index: include/llvm/Analysis/SparsePropagation.h
===================================================================
--- include/llvm/Analysis/SparsePropagation.h
+++ include/llvm/Analysis/SparsePropagation.h
@@ -15,33 +15,21 @@
#ifndef LLVM_ANALYSIS_SPARSEPROPAGATION_H
#define LLVM_ANALYSIS_SPARSEPROPAGATION_H
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/IR/Instructions.h"
+#include "llvm/Support/Debug.h"
#include <set>
-#include <utility>
-#include <vector>
+
+#define DEBUG_TYPE "sparseprop"
namespace llvm {
-class Argument;
-class BasicBlock;
-class Constant;
-class Function;
-class Instruction;
-class PHINode;
-class raw_ostream;
template <class LatticeVal> class SparseSolver;
-class TerminatorInst;
-class Value;
-template <typename T> class SmallVectorImpl;
/// AbstractLatticeFunction - This class is implemented by the dataflow instance
/// to specify what the lattice values are and how they handle merges etc. This
/// gives the client the power to compute lattice values from instructions,
/// constants, etc. The current requirement is that lattice values must be
/// copyable. At the moment, nothing tries to avoid copying.
-
-
template <class LatticeVal> class AbstractLatticeFunction {
private:
LatticeVal UndefVal, OverdefinedVal, UntrackedVal;
@@ -54,7 +42,7 @@
UntrackedVal = untrackedVal;
}
- virtual ~AbstractLatticeFunction();
+ virtual ~AbstractLatticeFunction() = default;
LatticeVal getUndefVal() const { return UndefVal; }
LatticeVal getOverdefinedVal() const { return OverdefinedVal; }
@@ -104,7 +92,16 @@
}
/// PrintValue - Render the specified lattice value to the specified stream.
- virtual void PrintValue(LatticeVal V, raw_ostream &OS);
+ virtual void PrintValue(LatticeVal V, raw_ostream &OS) {
+ if (V == UndefVal)
+ OS << "undefined";
+ else if (V == OverdefinedVal)
+ OS << "overdefined";
+ else if (V == UntrackedVal)
+ OS << "untracked";
+ else
+ OS << "unknown lattice value";
+ }
};
/// SparseSolver - This class is a general purpose solver for Sparse Conditional
@@ -132,12 +129,62 @@
: LatticeFunc(Lattice) {}
SparseSolver(const SparseSolver &) = delete;
SparseSolver &operator=(const SparseSolver &) = delete;
- ~SparseSolver() { delete LatticeFunc; }
/// Solve - Solve for constants and executable blocks.
- void Solve(Function &F);
+ void Solve(Function &F) {
+ MarkBlockExecutable(&F.getEntryBlock());
+
+ // Process the work lists until they are empty!
+ while (!BBWorkList.empty() || !InstWorkList.empty()) {
+ // Process the instruction work list.
+ while (!InstWorkList.empty()) {
+ Instruction *I = InstWorkList.back();
+ InstWorkList.pop_back();
+
+ DEBUG(dbgs() << "\nPopped off I-WL: " << *I << "\n");
+
+ // "I" got into the work list because it made a transition. See if any
+ // users are both live and in need of updating.
+ for (User *U : I->users()) {
+ Instruction *UI = cast<Instruction>(U);
+ if (BBExecutable.count(UI->getParent())) // Inst is executable?
+ visitInst(*UI);
+ }
+ }
+
+ // Process the basic block work list.
+ while (!BBWorkList.empty()) {
+ BasicBlock *BB = BBWorkList.back();
+ BBWorkList.pop_back();
+
+ DEBUG(dbgs() << "\nPopped off BBWL: " << *BB);
+
+ // Notify all instructions in this basic block that they are newly
+ // executable.
+ for (Instruction &I : *BB)
+ visitInst(I);
+ }
+ }
+ }
- void Print(Function &F, raw_ostream &OS) const;
+ void Print(Function &F, raw_ostream &OS) const {
+ OS << "\nFUNCTION: " << F.getName() << "\n";
+ for (auto &BB : F) {
+ if (!BBExecutable.count(&BB))
+ OS << "INFEASIBLE: ";
+ OS << "\t";
+ if (BB.hasName())
+ OS << BB.getName() << ":\n";
+ else
+ OS << "; anon bb\n";
+ for (auto &I : BB) {
+ LatticeFunc->PrintValue(getLatticeState(&I), OS);
+ OS << I << "\n";
+ }
+
+ OS << "\n";
+ }
+ }
/// getLatticeState - Return the LatticeVal object that corresponds to the
/// value. If an value is not in the map, it is returned as untracked,
@@ -152,7 +199,30 @@
/// map yet. This function is necessary because not all values should start
/// out in the underdefined state... Arguments should be overdefined, and
/// constants should be marked as constants.
- LatticeVal getValueState(Value *V);
+ LatticeVal getValueState(Value *V) {
+ auto I = ValueState.find(V);
+ if (I != ValueState.end())
+ return I->second; // Common case, in the map
+
+ LatticeVal LV;
+ if (LatticeFunc->IsUntrackedValue(V))
+ return LatticeFunc->getUntrackedVal();
+ else if (Constant *C = dyn_cast<Constant>(V))
+ LV = LatticeFunc->ComputeConstant(C);
+ else if (Argument *A = dyn_cast<Argument>(V))
+ LV = LatticeFunc->ComputeArgument(A);
+ else if (!isa<Instruction>(V))
+ // All other non-instructions are overdefined.
+ LV = LatticeFunc->getOverdefinedVal();
+ else
+ // All instructions are underdefined by default.
+ LV = LatticeFunc->getUndefVal();
+
+ // If this value is untracked, don't add it to the map.
+ if (LV == LatticeFunc->getUntrackedVal())
+ return LV;
+ return ValueState[V] = LV;
+ }
/// isEdgeFeasible - Return true if the control flow edge from the 'From'
/// basic block to the 'To' basic block is currently feasible. If
@@ -160,7 +230,17 @@
/// values as undefined. This is generally only useful when solving the
/// lattice, not when querying it.
bool isEdgeFeasible(BasicBlock *From, BasicBlock *To,
- bool AggressiveUndef = false);
+ bool AggressiveUndef = false) {
+ SmallVector<bool, 16> SuccFeasible;
+ TerminatorInst *TI = From->getTerminator();
+ getFeasibleSuccessors(*TI, SuccFeasible, AggressiveUndef);
+
+ for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
+ if (TI->getSuccessor(i) == To && SuccFeasible[i])
+ return true;
+
+ return false;
+ }
/// isBlockExecutable - Return true if there are any known feasible
/// edges into the basic block. This is generally only useful when
@@ -172,24 +252,201 @@
private:
/// UpdateState - When the state for some instruction is potentially updated,
/// this function notices and adds I to the worklist if needed.
- void UpdateState(Instruction &Inst, LatticeVal V);
+ void UpdateState(Instruction &Inst, LatticeVal V) {
+ auto I = ValueState.find(&Inst);
+ if (I != ValueState.end() && I->second == V)
+ return; // No change.
+
+ // An update. Visit uses of I.
+ ValueState[&Inst] = V;
+ InstWorkList.push_back(&Inst);
+ }
/// MarkBlockExecutable - This method can be used by clients to mark all of
/// the blocks that are known to be intrinsically live in the processed unit.
- void MarkBlockExecutable(BasicBlock *BB);
+ void MarkBlockExecutable(BasicBlock *BB) {
+ DEBUG(dbgs() << "Marking Block Executable: " << BB->getName() << "\n");
+ BBExecutable.insert(BB); // Basic block is executable!
+ BBWorkList.push_back(BB); // Add the block to the work list!
+ }
/// markEdgeExecutable - Mark a basic block as executable, adding it to the BB
/// work list if it is not already executable.
- void markEdgeExecutable(BasicBlock *Source, BasicBlock *Dest);
+ void markEdgeExecutable(BasicBlock *Source, BasicBlock *Dest) {
+ if (!KnownFeasibleEdges.insert(Edge(Source, Dest)).second)
+ return; // This edge is already known to be executable!
+
+ DEBUG(dbgs() << "Marking Edge Executable: " << Source->getName() << " -> "
+ << Dest->getName() << "\n");
+
+ if (BBExecutable.count(Dest)) {
+ // The destination is already executable, but we just made an edge
+ // feasible that wasn't before. Revisit the PHI nodes in the block
+ // because they have potentially new operands.
+ for (BasicBlock::iterator I = Dest->begin(); isa<PHINode>(I); ++I)
+ visitPHINode(*cast<PHINode>(I));
+ } else {
+ MarkBlockExecutable(Dest);
+ }
+ }
/// getFeasibleSuccessors - Return a vector of booleans to indicate which
/// successors are reachable from a given terminator instruction.
void getFeasibleSuccessors(TerminatorInst &TI, SmallVectorImpl<bool> &Succs,
- bool AggressiveUndef);
+ bool AggressiveUndef) {
+ Succs.resize(TI.getNumSuccessors());
+ if (TI.getNumSuccessors() == 0)
+ return;
+
+ if (BranchInst *BI = dyn_cast<BranchInst>(&TI)) {
+ if (BI->isUnconditional()) {
+ Succs[0] = true;
+ return;
+ }
+
+ LatticeVal BCValue;
+ if (AggressiveUndef)
+ BCValue = getValueState(BI->getCondition());
+ else
+ BCValue = getLatticeState(BI->getCondition());
+
+ if (BCValue == LatticeFunc->getOverdefinedVal() ||
+ BCValue == LatticeFunc->getUntrackedVal()) {
+ // Overdefined condition variables can branch either way.
+ Succs[0] = Succs[1] = true;
+ return;
+ }
+
+ // If undefined, neither is feasible yet.
+ if (BCValue == LatticeFunc->getUndefVal())
+ return;
+
+ Constant *C =
+ LatticeFunc->GetConstant(BCValue, BI->getCondition(), *this);
+ if (!C || !isa<ConstantInt>(C)) {
+ // Non-constant values can go either way.
+ Succs[0] = Succs[1] = true;
+ return;
+ }
+
+ // Constant condition variables mean the branch can only go a single way
+ Succs[C->isNullValue()] = true;
+ return;
+ }
+
+ if (isa<InvokeInst>(TI)) {
+ // Invoke instructions successors are always executable.
+ // TODO: Could ask the lattice function if the value can throw.
+ Succs[0] = Succs[1] = true;
+ return;
+ }
+
+ if (isa<IndirectBrInst>(TI)) {
+ Succs.assign(Succs.size(), true);
+ return;
+ }
+
+ SwitchInst &SI = cast<SwitchInst>(TI);
+ LatticeVal SCValue;
+ if (AggressiveUndef)
+ SCValue = getValueState(SI.getCondition());
+ else
+ SCValue = getLatticeState(SI.getCondition());
+
+ if (SCValue == LatticeFunc->getOverdefinedVal() ||
+ SCValue == LatticeFunc->getUntrackedVal()) {
+ // All destinations are executable!
+ Succs.assign(TI.getNumSuccessors(), true);
+ return;
+ }
+
+ // If undefined, neither is feasible yet.
+ if (SCValue == LatticeFunc->getUndefVal())
+ return;
+
+ Constant *C = LatticeFunc->GetConstant(SCValue, SI.getCondition(), *this);
+ if (!C || !isa<ConstantInt>(C)) {
+ // All destinations are executable!
+ Succs.assign(TI.getNumSuccessors(), true);
+ return;
+ }
+ SwitchInst::CaseHandle Case = *SI.findCaseValue(cast<ConstantInt>(C));
+ Succs[Case.getSuccessorIndex()] = true;
+ }
+
+ void visitInst(Instruction &I) {
+ // PHIs are handled by the propagation logic, they are never passed into the
+ // transfer functions.
+ if (PHINode *PN = dyn_cast<PHINode>(&I))
+ return visitPHINode(*PN);
+
+ // Otherwise, ask the transfer function what the result is. If this is
+ // something that we care about, remember it.
+ LatticeVal IV = LatticeFunc->ComputeInstructionState(I, *this);
+ if (IV != LatticeFunc->getUntrackedVal())
+ UpdateState(I, IV);
+
+ if (TerminatorInst *TI = dyn_cast<TerminatorInst>(&I))
+ visitTerminatorInst(*TI);
+ }
+
+ void visitPHINode(PHINode &PN) {
+ // The lattice function may store more information on a PHINode than could
+ // be computed from its incoming values. For example, SSI form stores its
+ // sigma functions as PHINodes with a single incoming value.
+ if (LatticeFunc->IsSpecialCasedPHI(&PN)) {
+ LatticeVal IV = LatticeFunc->ComputeInstructionState(PN, *this);
+ if (IV != LatticeFunc->getUntrackedVal())
+ UpdateState(PN, IV);
+ return;
+ }
+
+ LatticeVal PNIV = getValueState(&PN);
+ LatticeVal Overdefined = LatticeFunc->getOverdefinedVal();
+
+ // If this value is already overdefined (common) just return.
+ if (PNIV == Overdefined || PNIV == LatticeFunc->getUntrackedVal())
+ return; // Quick exit
+
+ // Super-extra-high-degree PHI nodes are unlikely to ever be interesting,
+ // and slow us down a lot. Just mark them overdefined.
+ if (PN.getNumIncomingValues() > 64) {
+ UpdateState(PN, Overdefined);
+ return;
+ }
+
+ // Look at all of the executable operands of the PHI node. If any of them
+ // are overdefined, the PHI becomes overdefined as well. Otherwise, ask the
+ // transfer function to give us the merge of the incoming values.
+ for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
+ // If the edge is not yet known to be feasible, it doesn't impact the PHI.
+ if (!isEdgeFeasible(PN.getIncomingBlock(i), PN.getParent(), true))
+ continue;
+
+ // Merge in this value.
+ LatticeVal OpVal = getValueState(PN.getIncomingValue(i));
+ if (OpVal != PNIV)
+ PNIV = LatticeFunc->MergeValues(PNIV, OpVal);
+
+ if (PNIV == Overdefined)
+ break; // Rest of input values don't matter.
+ }
+
+ // Update the PHI with the compute value, which is the merge of the inputs.
+ UpdateState(PN, PNIV);
+ }
- void visitInst(Instruction &I);
- void visitPHINode(PHINode &I);
- void visitTerminatorInst(TerminatorInst &TI);
+ void visitTerminatorInst(TerminatorInst &TI) {
+ SmallVector<bool, 16> SuccFeasible;
+ getFeasibleSuccessors(TI, SuccFeasible, true);
+
+ BasicBlock *BB = TI.getParent();
+
+ // Mark all feasible successors executable...
+ for (unsigned i = 0, e = SuccFeasible.size(); i != e; ++i)
+ if (SuccFeasible[i])
+ markEdgeExecutable(BB, TI.getSuccessor(i));
+ }
};
} // end namespace llvm
Index: lib/Analysis/CMakeLists.txt
===================================================================
--- lib/Analysis/CMakeLists.txt
+++ lib/Analysis/CMakeLists.txt
@@ -75,7 +75,6 @@
ScalarEvolutionAliasAnalysis.cpp
ScalarEvolutionExpander.cpp
ScalarEvolutionNormalization.cpp
- SparsePropagation.cpp
TargetLibraryInfo.cpp
TargetTransformInfo.cpp
Trace.cpp
Index: lib/Analysis/SparsePropagation.cpp
===================================================================
--- lib/Analysis/SparsePropagation.cpp
+++ /dev/null
@@ -1,364 +0,0 @@
-//===- SparsePropagation.cpp - Sparse Conditional Property Propagation ----===//
-//
-// The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// This file implements an abstract sparse conditional propagation algorithm,
-// modeled after SCCP, but with a customizable lattice function.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/Analysis/SparsePropagation.h"
-#include "llvm/ADT/DenseMap.h"
-#include "llvm/ADT/SmallVector.h"
-#include "llvm/IR/Argument.h"
-#include "llvm/IR/BasicBlock.h"
-#include "llvm/IR/Constant.h"
-#include "llvm/IR/Constants.h"
-#include "llvm/IR/Function.h"
-#include "llvm/IR/InstrTypes.h"
-#include "llvm/IR/Instruction.h"
-#include "llvm/IR/Instructions.h"
-#include "llvm/IR/User.h"
-#include "llvm/Support/Casting.h"
-#include "llvm/Support/Debug.h"
-#include "llvm/Support/raw_ostream.h"
-
-using namespace llvm;
-
-#define DEBUG_TYPE "sparseprop"
-
-//===----------------------------------------------------------------------===//
-// AbstractLatticeFunction Implementation
-//===----------------------------------------------------------------------===//
-
-template <class LatticeVal>
-AbstractLatticeFunction<LatticeVal>::~AbstractLatticeFunction() = default;
-
-/// PrintValue - Render the specified lattice value to the specified stream.
-template <class LatticeVal>
-void AbstractLatticeFunction<LatticeVal>::PrintValue(LatticeVal V,
- raw_ostream &OS) {
- if (V == UndefVal)
- OS << "undefined";
- else if (V == OverdefinedVal)
- OS << "overdefined";
- else if (V == UntrackedVal)
- OS << "untracked";
- else
- OS << "unknown lattice value";
-}
-
-//===----------------------------------------------------------------------===//
-// SparseSolver Implementation
-//===----------------------------------------------------------------------===//
-
-/// getValueState - Return the LatticeVal object that corresponds to the
-/// value, initializing the value's state if it hasn't been entered into the
-/// map yet. This function is necessary because not all values should start
-/// out in the underdefined state... Arguments should be overdefined, and
-/// constants should be marked as constants.
-template <class LatticeVal>
-LatticeVal SparseSolver<LatticeVal>::getValueState(Value *V) {
- auto I = ValueState.find(V);
- if (I != ValueState.end()) return I->second; // Common case, in the map
-
- LatticeVal LV;
- if (LatticeFunc->IsUntrackedValue(V))
- return LatticeFunc->getUntrackedVal();
- else if (Constant *C = dyn_cast<Constant>(V))
- LV = LatticeFunc->ComputeConstant(C);
- else if (Argument *A = dyn_cast<Argument>(V))
- LV = LatticeFunc->ComputeArgument(A);
- else if (!isa<Instruction>(V))
- // All other non-instructions are overdefined.
- LV = LatticeFunc->getOverdefinedVal();
- else
- // All instructions are underdefined by default.
- LV = LatticeFunc->getUndefVal();
-
- // If this value is untracked, don't add it to the map.
- if (LV == LatticeFunc->getUntrackedVal())
- return LV;
- return ValueState[V] = LV;
-}
-
-/// UpdateState - When the state for some instruction is potentially updated,
-/// this function notices and adds I to the worklist if needed.
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::UpdateState(Instruction &Inst, LatticeVal V) {
- auto I = ValueState.find(&Inst);
- if (I != ValueState.end() && I->second == V)
- return; // No change.
-
- // An update. Visit uses of I.
- ValueState[&Inst] = V;
- InstWorkList.push_back(&Inst);
-}
-
-/// MarkBlockExecutable - This method can be used by clients to mark all of
-/// the blocks that are known to be intrinsically live in the processed unit.
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::MarkBlockExecutable(BasicBlock *BB) {
- DEBUG(dbgs() << "Marking Block Executable: " << BB->getName() << "\n");
- BBExecutable.insert(BB); // Basic block is executable!
- BBWorkList.push_back(BB); // Add the block to the work list!
-}
-
-/// markEdgeExecutable - Mark a basic block as executable, adding it to the BB
-/// work list if it is not already executable...
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::markEdgeExecutable(BasicBlock *Source,
- BasicBlock *Dest) {
- if (!KnownFeasibleEdges.insert(Edge(Source, Dest)).second)
- return; // This edge is already known to be executable!
-
- DEBUG(dbgs() << "Marking Edge Executable: " << Source->getName()
- << " -> " << Dest->getName() << "\n");
-
- if (BBExecutable.count(Dest)) {
- // The destination is already executable, but we just made an edge
- // feasible that wasn't before. Revisit the PHI nodes in the block
- // because they have potentially new operands.
- for (BasicBlock::iterator I = Dest->begin(); isa<PHINode>(I); ++I)
- visitPHINode(*cast<PHINode>(I));
- } else {
- MarkBlockExecutable(Dest);
- }
-}
-
-/// getFeasibleSuccessors - Return a vector of booleans to indicate which
-/// successors are reachable from a given terminator instruction.
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::getFeasibleSuccessors(
- TerminatorInst &TI, SmallVectorImpl<bool> &Succs, bool AggressiveUndef) {
- Succs.resize(TI.getNumSuccessors());
- if (TI.getNumSuccessors() == 0) return;
-
- if (BranchInst *BI = dyn_cast<BranchInst>(&TI)) {
- if (BI->isUnconditional()) {
- Succs[0] = true;
- return;
- }
-
- LatticeVal BCValue;
- if (AggressiveUndef)
- BCValue = getValueState(BI->getCondition());
- else
- BCValue = getLatticeState(BI->getCondition());
-
- if (BCValue == LatticeFunc->getOverdefinedVal() ||
- BCValue == LatticeFunc->getUntrackedVal()) {
- // Overdefined condition variables can branch either way.
- Succs[0] = Succs[1] = true;
- return;
- }
-
- // If undefined, neither is feasible yet.
- if (BCValue == LatticeFunc->getUndefVal())
- return;
-
- Constant *C = LatticeFunc->GetConstant(BCValue, BI->getCondition(), *this);
- if (!C || !isa<ConstantInt>(C)) {
- // Non-constant values can go either way.
- Succs[0] = Succs[1] = true;
- return;
- }
-
- // Constant condition variables mean the branch can only go a single way
- Succs[C->isNullValue()] = true;
- return;
- }
-
- if (isa<InvokeInst>(TI)) {
- // Invoke instructions successors are always executable.
- // TODO: Could ask the lattice function if the value can throw.
- Succs[0] = Succs[1] = true;
- return;
- }
-
- if (isa<IndirectBrInst>(TI)) {
- Succs.assign(Succs.size(), true);
- return;
- }
-
- SwitchInst &SI = cast<SwitchInst>(TI);
- LatticeVal SCValue;
- if (AggressiveUndef)
- SCValue = getValueState(SI.getCondition());
- else
- SCValue = getLatticeState(SI.getCondition());
-
- if (SCValue == LatticeFunc->getOverdefinedVal() ||
- SCValue == LatticeFunc->getUntrackedVal()) {
- // All destinations are executable!
- Succs.assign(TI.getNumSuccessors(), true);
- return;
- }
-
- // If undefined, neither is feasible yet.
- if (SCValue == LatticeFunc->getUndefVal())
- return;
-
- Constant *C = LatticeFunc->GetConstant(SCValue, SI.getCondition(), *this);
- if (!C || !isa<ConstantInt>(C)) {
- // All destinations are executable!
- Succs.assign(TI.getNumSuccessors(), true);
- return;
- }
- SwitchInst::CaseHandle Case = *SI.findCaseValue(cast<ConstantInt>(C));
- Succs[Case.getSuccessorIndex()] = true;
-}
-
-/// isEdgeFeasible - Return true if the control flow edge from the 'From'
-/// basic block to the 'To' basic block is currently feasible...
-template <class LatticeVal>
-bool SparseSolver<LatticeVal>::isEdgeFeasible(BasicBlock *From, BasicBlock *To,
- bool AggressiveUndef) {
- SmallVector<bool, 16> SuccFeasible;
- TerminatorInst *TI = From->getTerminator();
- getFeasibleSuccessors(*TI, SuccFeasible, AggressiveUndef);
-
- for (unsigned i = 0, e = TI->getNumSuccessors(); i != e; ++i)
- if (TI->getSuccessor(i) == To && SuccFeasible[i])
- return true;
-
- return false;
-}
-
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::visitTerminatorInst(TerminatorInst &TI) {
- SmallVector<bool, 16> SuccFeasible;
- getFeasibleSuccessors(TI, SuccFeasible, true);
-
- BasicBlock *BB = TI.getParent();
-
- // Mark all feasible successors executable...
- for (unsigned i = 0, e = SuccFeasible.size(); i != e; ++i)
- if (SuccFeasible[i])
- markEdgeExecutable(BB, TI.getSuccessor(i));
-}
-
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::visitPHINode(PHINode &PN) {
- // The lattice function may store more information on a PHINode than could be
- // computed from its incoming values. For example, SSI form stores its sigma
- // functions as PHINodes with a single incoming value.
- if (LatticeFunc->IsSpecialCasedPHI(&PN)) {
- LatticeVal IV = LatticeFunc->ComputeInstructionState(PN, *this);
- if (IV != LatticeFunc->getUntrackedVal())
- UpdateState(PN, IV);
- return;
- }
-
- LatticeVal PNIV = getValueState(&PN);
- LatticeVal Overdefined = LatticeFunc->getOverdefinedVal();
-
- // If this value is already overdefined (common) just return.
- if (PNIV == Overdefined || PNIV == LatticeFunc->getUntrackedVal())
- return; // Quick exit
-
- // Super-extra-high-degree PHI nodes are unlikely to ever be interesting,
- // and slow us down a lot. Just mark them overdefined.
- if (PN.getNumIncomingValues() > 64) {
- UpdateState(PN, Overdefined);
- return;
- }
-
- // Look at all of the executable operands of the PHI node. If any of them
- // are overdefined, the PHI becomes overdefined as well. Otherwise, ask the
- // transfer function to give us the merge of the incoming values.
- for (unsigned i = 0, e = PN.getNumIncomingValues(); i != e; ++i) {
- // If the edge is not yet known to be feasible, it doesn't impact the PHI.
- if (!isEdgeFeasible(PN.getIncomingBlock(i), PN.getParent(), true))
- continue;
-
- // Merge in this value.
- LatticeVal OpVal = getValueState(PN.getIncomingValue(i));
- if (OpVal != PNIV)
- PNIV = LatticeFunc->MergeValues(PNIV, OpVal);
-
- if (PNIV == Overdefined)
- break; // Rest of input values don't matter.
- }
-
- // Update the PHI with the compute value, which is the merge of the inputs.
- UpdateState(PN, PNIV);
-}
-
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::visitInst(Instruction &I) {
- // PHIs are handled by the propagation logic, they are never passed into the
- // transfer functions.
- if (PHINode *PN = dyn_cast<PHINode>(&I))
- return visitPHINode(*PN);
-
- // Otherwise, ask the transfer function what the result is. If this is
- // something that we care about, remember it.
- LatticeVal IV = LatticeFunc->ComputeInstructionState(I, *this);
- if (IV != LatticeFunc->getUntrackedVal())
- UpdateState(I, IV);
-
- if (TerminatorInst *TI = dyn_cast<TerminatorInst>(&I))
- visitTerminatorInst(*TI);
-}
-
-template <class LatticeVal> void SparseSolver<LatticeVal>::Solve(Function &F) {
- MarkBlockExecutable(&F.getEntryBlock());
-
- // Process the work lists until they are empty!
- while (!BBWorkList.empty() || !InstWorkList.empty()) {
- // Process the instruction work list.
- while (!InstWorkList.empty()) {
- Instruction *I = InstWorkList.back();
- InstWorkList.pop_back();
-
- DEBUG(dbgs() << "\nPopped off I-WL: " << *I << "\n");
-
- // "I" got into the work list because it made a transition. See if any
- // users are both live and in need of updating.
- for (User *U : I->users()) {
- Instruction *UI = cast<Instruction>(U);
- if (BBExecutable.count(UI->getParent())) // Inst is executable?
- visitInst(*UI);
- }
- }
-
- // Process the basic block work list.
- while (!BBWorkList.empty()) {
- BasicBlock *BB = BBWorkList.back();
- BBWorkList.pop_back();
-
- DEBUG(dbgs() << "\nPopped off BBWL: " << *BB);
-
- // Notify all instructions in this basic block that they are newly
- // executable.
- for (Instruction &I : *BB)
- visitInst(I);
- }
- }
-}
-
-template <class LatticeVal>
-void SparseSolver<LatticeVal>::Print(Function &F, raw_ostream &OS) const {
- OS << "\nFUNCTION: " << F.getName() << "\n";
- for (auto &BB : F) {
- if (!BBExecutable.count(&BB))
- OS << "INFEASIBLE: ";
- OS << "\t";
- if (BB.hasName())
- OS << BB.getName() << ":\n";
- else
- OS << "; anon bb\n";
- for (auto &I : BB) {
- LatticeFunc->PrintValue(getLatticeState(&I), OS);
- OS << I << "\n";
- }
-
- OS << "\n";
- }
-}