#include "llvm/ADT/DepthFirstIterator.h"
#include "llvm/ADT/PostOrderIterator.h"
#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Transforms/Utils/UnifyFunctionExitNodes.h"
#include "llvm/Support/CFG.h"
#include <algorithm>
#include <deque>
#include <map>
-#include <vector>
-#include <set>
using namespace llvm;
//===----------------------------------------------------------------------===//
/// as an efficient mechanism to determine the expression-wise equivalence of
/// two values.
-namespace {
- class VISIBILITY_HIDDEN ValueTable {
- public:
- struct Expression {
- enum ExpressionOpcode { ADD, SUB, MUL, UDIV, SDIV, FDIV, UREM, SREM,
- FREM, SHL, LSHR, ASHR, AND, OR, XOR, ICMPEQ,
- ICMPNE, ICMPUGT, ICMPUGE, ICMPULT, ICMPULE,
- ICMPSGT, ICMPSGE, ICMPSLT, ICMPSLE, FCMPOEQ,
- FCMPOGT, FCMPOGE, FCMPOLT, FCMPOLE, FCMPONE,
- FCMPORD, FCMPUNO, FCMPUEQ, FCMPUGT, FCMPUGE,
- FCMPULT, FCMPULE, FCMPUNE, EXTRACT, INSERT,
- SHUFFLE, SELECT, TRUNC, ZEXT, SEXT, FPTOUI,
- FPTOSI, UITOFP, SITOFP, FPTRUNC, FPEXT,
- PTRTOINT, INTTOPTR, BITCAST, GEP};
-
- ExpressionOpcode opcode;
- const Type* type;
- uint32_t firstVN;
- uint32_t secondVN;
- uint32_t thirdVN;
- std::vector<uint32_t> varargs;
+struct Expression {
+ enum ExpressionOpcode { ADD, SUB, MUL, UDIV, SDIV, FDIV, UREM, SREM,
+ FREM, SHL, LSHR, ASHR, AND, OR, XOR, ICMPEQ,
+ ICMPNE, ICMPUGT, ICMPUGE, ICMPULT, ICMPULE,
+ ICMPSGT, ICMPSGE, ICMPSLT, ICMPSLE, FCMPOEQ,
+ FCMPOGT, FCMPOGE, FCMPOLT, FCMPOLE, FCMPONE,
+ FCMPORD, FCMPUNO, FCMPUEQ, FCMPUGT, FCMPUGE,
+ FCMPULT, FCMPULE, FCMPUNE, EXTRACT, INSERT,
+ SHUFFLE, SELECT, TRUNC, ZEXT, SEXT, FPTOUI,
+ FPTOSI, UITOFP, SITOFP, FPTRUNC, FPEXT,
+ PTRTOINT, INTTOPTR, BITCAST, GEP, EMPTY,
+ TOMBSTONE };
+
+ ExpressionOpcode opcode;
+ const Type* type;
+ uint32_t firstVN;
+ uint32_t secondVN;
+ uint32_t thirdVN;
+ SmallVector<uint32_t, 4> varargs;
+
+ Expression() { }
+ Expression(ExpressionOpcode o) : opcode(o) { }
+
+ bool operator==(const Expression &other) const {
+ if (opcode != other.opcode)
+ return false;
+ else if (opcode == EMPTY || opcode == TOMBSTONE)
+ return true;
+ else if (type != other.type)
+ return false;
+ else if (firstVN != other.firstVN)
+ return false;
+ else if (secondVN != other.secondVN)
+ return false;
+ else if (thirdVN != other.thirdVN)
+ return false;
+ else {
+ if (varargs.size() != other.varargs.size())
+ return false;
- bool operator< (const Expression& other) const {
- if (opcode < other.opcode)
- return true;
- else if (opcode > other.opcode)
- return false;
- else if (type < other.type)
- return true;
- else if (type > other.type)
- return false;
- else if (firstVN < other.firstVN)
- return true;
- else if (firstVN > other.firstVN)
- return false;
- else if (secondVN < other.secondVN)
- return true;
- else if (secondVN > other.secondVN)
- return false;
- else if (thirdVN < other.thirdVN)
- return true;
- else if (thirdVN > other.thirdVN)
- return false;
- else {
- if (varargs.size() < other.varargs.size())
- return true;
- else if (varargs.size() > other.varargs.size())
- return false;
-
- for (size_t i = 0; i < varargs.size(); ++i)
- if (varargs[i] < other.varargs[i])
- return true;
- else if (varargs[i] > other.varargs[i])
- return false;
-
- return false;
- }
- }
- };
+ for (size_t i = 0; i < varargs.size(); ++i)
+ if (varargs[i] != other.varargs[i])
+ return false;
+ return true;
+ }
+ }
+
+ bool operator!=(const Expression &other) const {
+ if (opcode != other.opcode)
+ return true;
+ else if (opcode == EMPTY || opcode == TOMBSTONE)
+ return false;
+ else if (type != other.type)
+ return true;
+ else if (firstVN != other.firstVN)
+ return true;
+ else if (secondVN != other.secondVN)
+ return true;
+ else if (thirdVN != other.thirdVN)
+ return true;
+ else {
+ if (varargs.size() != other.varargs.size())
+ return true;
+
+ for (size_t i = 0; i < varargs.size(); ++i)
+ if (varargs[i] != other.varargs[i])
+ return true;
+
+ return false;
+ }
+ }
+};
+
+
+namespace {
+ class VISIBILITY_HIDDEN ValueTable {
private:
DenseMap<Value*, uint32_t> valueNumbering;
- std::map<Expression, uint32_t> expressionNumbering;
+ DenseMap<Expression, uint32_t> expressionNumbering;
uint32_t nextValueNumber;
};
}
+namespace llvm {
+template <> struct DenseMapKeyInfo<Expression> {
+ static inline Expression getEmptyKey() {
+ return Expression(Expression::EMPTY);
+ }
+
+ static inline Expression getTombstoneKey() {
+ return Expression(Expression::TOMBSTONE);
+ }
+
+ static unsigned getHashValue(const Expression e) {
+ unsigned hash = e.opcode;
+
+ hash = e.firstVN + hash * 37;
+ hash = e.secondVN + hash * 37;
+ hash = e.thirdVN + hash * 37;
+
+ hash = (unsigned)((uintptr_t)e.type >> 4) ^
+ (unsigned)((uintptr_t)e.type >> 9) +
+ hash * 37;
+
+ for (SmallVector<uint32_t, 4>::const_iterator I = e.varargs.begin(),
+ E = e.varargs.end(); I != E; ++I)
+ hash = *I + hash * 37;
+
+ return hash;
+ }
+ static bool isPod() { return true; }
+};
+}
+
//===----------------------------------------------------------------------===//
// ValueTable Internal Functions
//===----------------------------------------------------------------------===//
-ValueTable::Expression::ExpressionOpcode
+Expression::ExpressionOpcode
ValueTable::getOpcode(BinaryOperator* BO) {
switch(BO->getOpcode()) {
case Instruction::Add:
}
}
-ValueTable::Expression::ExpressionOpcode ValueTable::getOpcode(CmpInst* C) {
+Expression::ExpressionOpcode ValueTable::getOpcode(CmpInst* C) {
if (C->getOpcode() == Instruction::ICmp) {
switch (C->getPredicate()) {
case ICmpInst::ICMP_EQ:
}
}
-ValueTable::Expression::ExpressionOpcode
+Expression::ExpressionOpcode
ValueTable::getOpcode(CastInst* C) {
switch(C->getOpcode()) {
case Instruction::Trunc:
}
}
-ValueTable::Expression ValueTable::create_expression(BinaryOperator* BO) {
+Expression ValueTable::create_expression(BinaryOperator* BO) {
Expression e;
e.firstVN = lookup_or_add(BO->getOperand(0));
return e;
}
-ValueTable::Expression ValueTable::create_expression(CmpInst* C) {
+Expression ValueTable::create_expression(CmpInst* C) {
Expression e;
e.firstVN = lookup_or_add(C->getOperand(0));
return e;
}
-ValueTable::Expression ValueTable::create_expression(CastInst* C) {
+Expression ValueTable::create_expression(CastInst* C) {
Expression e;
e.firstVN = lookup_or_add(C->getOperand(0));
return e;
}
-ValueTable::Expression ValueTable::create_expression(ShuffleVectorInst* S) {
+Expression ValueTable::create_expression(ShuffleVectorInst* S) {
Expression e;
e.firstVN = lookup_or_add(S->getOperand(0));
return e;
}
-ValueTable::Expression ValueTable::create_expression(ExtractElementInst* E) {
+Expression ValueTable::create_expression(ExtractElementInst* E) {
Expression e;
e.firstVN = lookup_or_add(E->getOperand(0));
return e;
}
-ValueTable::Expression ValueTable::create_expression(InsertElementInst* I) {
+Expression ValueTable::create_expression(InsertElementInst* I) {
Expression e;
e.firstVN = lookup_or_add(I->getOperand(0));
return e;
}
-ValueTable::Expression ValueTable::create_expression(SelectInst* I) {
+Expression ValueTable::create_expression(SelectInst* I) {
Expression e;
e.firstVN = lookup_or_add(I->getCondition());
return e;
}
-ValueTable::Expression ValueTable::create_expression(GetElementPtrInst* G) {
+Expression ValueTable::create_expression(GetElementPtrInst* G) {
Expression e;
e.firstVN = lookup_or_add(G->getPointerOperand());
e.secondVN = 0;
e.thirdVN = 0;
e.type = G->getType();
- e.opcode = Expression::SELECT;
+ e.opcode = Expression::GEP;
for (GetElementPtrInst::op_iterator I = G->idx_begin(), E = G->idx_end();
I != E; ++I)
if (BinaryOperator* BO = dyn_cast<BinaryOperator>(V)) {
Expression e = create_expression(BO);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (CmpInst* C = dyn_cast<CmpInst>(V)) {
Expression e = create_expression(C);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (ShuffleVectorInst* U = dyn_cast<ShuffleVectorInst>(V)) {
Expression e = create_expression(U);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (ExtractElementInst* U = dyn_cast<ExtractElementInst>(V)) {
Expression e = create_expression(U);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (InsertElementInst* U = dyn_cast<InsertElementInst>(V)) {
Expression e = create_expression(U);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (SelectInst* U = dyn_cast<SelectInst>(V)) {
Expression e = create_expression(U);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (CastInst* U = dyn_cast<CastInst>(V)) {
Expression e = create_expression(U);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
} else if (GetElementPtrInst* U = dyn_cast<GetElementPtrInst>(V)) {
Expression e = create_expression(U);
- std::map<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
+ DenseMap<Expression, uint32_t>::iterator EI = expressionNumbering.find(e);
if (EI != expressionNumbering.end()) {
valueNumbering.insert(std::make_pair(V, EI->second));
return EI->second;
BitVector numbers;
public:
ValueNumberedSet() { numbers.resize(1); }
+ ValueNumberedSet(const ValueNumberedSet& other) {
+ numbers = other.numbers;
+ contents = other.contents;
+ }
typedef SmallPtrSet<Value*, 8>::iterator iterator;
bool insert(Value* v) { return contents.insert(v); }
void insert(iterator I, iterator E) { contents.insert(I, E); }
void erase(Value* v) { contents.erase(v); }
+ unsigned count(Value* v) { return contents.count(v); }
size_t size() { return contents.size(); }
void set(unsigned i) {
private:
ValueTable VN;
- std::vector<Instruction*> createdExpressions;
+ SmallVector<Instruction*, 8> createdExpressions;
- std::map<BasicBlock*, ValueNumberedSet> availableOut;
- std::map<BasicBlock*, ValueNumberedSet> anticipatedIn;
- std::map<BasicBlock*, ValueNumberedSet> generatedPhis;
+ DenseMap<BasicBlock*, ValueNumberedSet> availableOut;
+ DenseMap<BasicBlock*, ValueNumberedSet> anticipatedIn;
+ DenseMap<BasicBlock*, ValueNumberedSet> generatedPhis;
// This transformation requires dominator postdominator info
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
BasicBlock* succ, ValueNumberedSet& out) ;
void topo_sort(ValueNumberedSet& set,
- std::vector<Value*>& vec) ;
+ SmallVector<Value*, 8>& vec) ;
void cleanup() ;
bool elimination() ;
ValueNumberedSet& currAvail,
ValueNumberedSet& currPhis,
ValueNumberedSet& currExps,
- SmallPtrSet<Value*, 16>& currTemps) ;
+ SmallPtrSet<Value*, 16>& currTemps);
bool buildsets_anticout(BasicBlock* BB,
ValueNumberedSet& anticOut,
- std::set<BasicBlock*>& visited) ;
+ SmallPtrSet<BasicBlock*, 8>& visited);
unsigned buildsets_anticin(BasicBlock* BB,
ValueNumberedSet& anticOut,
ValueNumberedSet& currExps,
SmallPtrSet<Value*, 16>& currTemps,
- std::set<BasicBlock*>& visited) ;
+ SmallPtrSet<BasicBlock*, 8>& visited);
void buildsets(Function& F) ;
void insertion_pre(Value* e, BasicBlock* BB,
- std::map<BasicBlock*, Value*>& avail,
- std::map<BasicBlock*,ValueNumberedSet>& new_set) ;
- unsigned insertion_mergepoint(std::vector<Value*>& workList,
+ DenseMap<BasicBlock*, Value*>& avail,
+ std::map<BasicBlock*,ValueNumberedSet>& new_set);
+ unsigned insertion_mergepoint(SmallVector<Value*, 8>& workList,
df_iterator<DomTreeNode*>& D,
- std::map<BasicBlock*, ValueNumberedSet>& new_set) ;
+ std::map<BasicBlock*, ValueNumberedSet>& new_set);
bool insertion(Function& F) ;
};
// createGVNPREPass - The public interface to this file...
FunctionPass *llvm::createGVNPREPass() { return new GVNPRE(); }
-RegisterPass<GVNPRE> X("gvnpre",
- "Global Value Numbering/Partial Redundancy Elimination");
+static RegisterPass<GVNPRE> X("gvnpre",
+ "Global Value Numbering/Partial Redundancy Elimination");
STATISTIC(NumInsertedVals, "Number of values inserted");
if (v == VN.lookup(*I))
return *I;
+ assert(0 && "No leader found, but present bit is set?");
return 0;
}
/// val_replace - Insert a value into a set, replacing any values already in
/// the set that have the same value number
void GVNPRE::val_replace(ValueNumberedSet& s, Value* v) {
+ if (s.count(v)) return;
+
uint32_t num = VN.lookup(v);
Value* leader = find_leader(s, num);
if (leader != 0)
return 0;
bool changed_idx = false;
- std::vector<Value*> newIdx;
+ SmallVector<Value*, 4> newIdx;
for (GetElementPtrInst::op_iterator I = U->idx_begin(), E = U->idx_end();
I != E; ++I)
if (isa<Instruction>(*I)) {
/// themselves in the set, as well as all values that depend on invokes (see
/// above)
void GVNPRE::clean(ValueNumberedSet& set) {
- std::vector<Value*> worklist;
+ SmallVector<Value*, 8> worklist;
worklist.reserve(set.size());
topo_sort(set, worklist);
/// topo_sort - Given a set of values, sort them by topological
/// order into the provided vector.
-void GVNPRE::topo_sort(ValueNumberedSet& set, std::vector<Value*>& vec) {
+void GVNPRE::topo_sort(ValueNumberedSet& set, SmallVector<Value*, 8>& vec) {
SmallPtrSet<Value*, 16> visited;
- std::vector<Value*> stack;
+ SmallVector<Value*, 8> stack;
for (ValueNumberedSet::iterator I = set.begin(), E = set.end();
I != E; ++I) {
if (visited.count(*I) == 0)
bool GVNPRE::elimination() {
bool changed_function = false;
- std::vector<std::pair<Instruction*, Value*> > replace;
- std::vector<Instruction*> erase;
+ SmallVector<std::pair<Instruction*, Value*>, 8> replace;
+ SmallVector<Instruction*, 8> erase;
DominatorTree& DT = getAnalysis<DominatorTree>();
isa<ShuffleVectorInst>(BI) || isa<InsertElementInst>(BI) ||
isa<ExtractElementInst>(BI) || isa<SelectInst>(BI) ||
isa<CastInst>(BI) || isa<GetElementPtrInst>(BI)) {
- Value *leader = find_leader(availableOut[BB], VN.lookup(BI));
-
- if (leader != 0)
+
+ if (availableOut[BB].test(VN.lookup(BI)) &&
+ !availableOut[BB].count(BI)) {
+ Value *leader = find_leader(availableOut[BB], VN.lookup(BI));
if (Instruction* Instr = dyn_cast<Instruction>(leader))
if (Instr->getParent() != 0 && Instr != BI) {
replace.push_back(std::make_pair(BI, leader));
erase.push_back(BI);
++NumEliminated;
}
+ }
}
}
}
changed_function = true;
}
- for (std::vector<Instruction*>::iterator I = erase.begin(), E = erase.end();
- I != E; ++I)
+ for (SmallVector<Instruction*, 8>::iterator I = erase.begin(),
+ E = erase.end(); I != E; ++I)
(*I)->eraseFromParent();
return changed_function;
/// set as a function of the ANTIC_IN set of the block's predecessors
bool GVNPRE::buildsets_anticout(BasicBlock* BB,
ValueNumberedSet& anticOut,
- std::set<BasicBlock*>& visited) {
+ SmallPtrSet<BasicBlock*, 8>& visited) {
if (BB->getTerminator()->getNumSuccessors() == 1) {
if (BB->getTerminator()->getSuccessor(0) != BB &&
visited.count(BB->getTerminator()->getSuccessor(0)) == 0) {
BasicBlock* currSucc = BB->getTerminator()->getSuccessor(i);
ValueNumberedSet& succAnticIn = anticipatedIn[currSucc];
- std::vector<Value*> temp;
+ SmallVector<Value*, 16> temp;
for (ValueNumberedSet::iterator I = anticOut.begin(),
E = anticOut.end(); I != E; ++I)
if (!succAnticIn.test(VN.lookup(*I)))
temp.push_back(*I);
- for (std::vector<Value*>::iterator I = temp.begin(), E = temp.end();
+ for (SmallVector<Value*, 16>::iterator I = temp.begin(), E = temp.end();
I != E; ++I) {
anticOut.erase(*I);
anticOut.reset(VN.lookup(*I));
ValueNumberedSet& anticOut,
ValueNumberedSet& currExps,
SmallPtrSet<Value*, 16>& currTemps,
- std::set<BasicBlock*>& visited) {
+ SmallPtrSet<BasicBlock*, 8>& visited) {
ValueNumberedSet& anticIn = anticipatedIn[BB];
unsigned old = anticIn.size();
/// buildsets - Phase 1 of the main algorithm. Construct the AVAIL_OUT
/// and the ANTIC_IN sets.
void GVNPRE::buildsets(Function& F) {
- std::map<BasicBlock*, ValueNumberedSet> generatedExpressions;
- std::map<BasicBlock*, SmallPtrSet<Value*, 16> > generatedTemporaries;
+ DenseMap<BasicBlock*, ValueNumberedSet> generatedExpressions;
+ DenseMap<BasicBlock*, SmallPtrSet<Value*, 16> > generatedTemporaries;
DominatorTree &DT = getAnalysis<DominatorTree>();
// Phase 1, Part 2: calculate ANTIC_IN
- std::set<BasicBlock*> visited;
+ SmallPtrSet<BasicBlock*, 8> visited;
SmallPtrSet<BasicBlock*, 4> block_changed;
for (Function::iterator FI = F.begin(), FE = F.end(); FI != FE; ++FI)
block_changed.insert(FI);
/// by inserting appropriate values into the predecessors and a phi node in
/// the main block
void GVNPRE::insertion_pre(Value* e, BasicBlock* BB,
- std::map<BasicBlock*, Value*>& avail,
+ DenseMap<BasicBlock*, Value*>& avail,
std::map<BasicBlock*, ValueNumberedSet>& new_sets) {
for (pred_iterator PI = pred_begin(BB), PE = pred_end(BB); PI != PE; ++PI) {
Value* e2 = avail[*PI];
}
// Vararg operators
- std::vector<Value*> sVarargs;
+ SmallVector<Value*, 4> sVarargs;
if (GetElementPtrInst* G = dyn_cast<GetElementPtrInst>(U)) {
for (GetElementPtrInst::op_iterator OI = G->idx_begin(),
OE = G->idx_end(); OI != OE; ++OI) {
val_replace(new_sets[*PI], newVal);
predAvail.set(VN.lookup(newVal));
- std::map<BasicBlock*, Value*>::iterator av = avail.find(*PI);
+ DenseMap<BasicBlock*, Value*>::iterator av = avail.find(*PI);
if (av != avail.end())
avail.erase(av);
avail.insert(std::make_pair(*PI, newVal));
/// insertion_mergepoint - When walking the dom tree, check at each merge
/// block for the possibility of a partial redundancy. If present, eliminate it
-unsigned GVNPRE::insertion_mergepoint(std::vector<Value*>& workList,
+unsigned GVNPRE::insertion_mergepoint(SmallVector<Value*, 8>& workList,
df_iterator<DomTreeNode*>& D,
std::map<BasicBlock*, ValueNumberedSet >& new_sets) {
bool changed_function = false;
if (availableOut[D->getIDom()->getBlock()].test(VN.lookup(e)))
continue;
- std::map<BasicBlock*, Value*> avail;
+ DenseMap<BasicBlock*, Value*> avail;
bool by_some = false;
bool all_same = true;
Value * first_s = 0;
Value *e3 = find_leader(availableOut[*PI], VN.lookup(e2));
if (e3 == 0) {
- std::map<BasicBlock*, Value*>::iterator av = avail.find(*PI);
+ DenseMap<BasicBlock*, Value*>::iterator av = avail.find(*PI);
if (av != avail.end())
avail.erase(av);
avail.insert(std::make_pair(*PI, e2));
all_same = false;
} else {
- std::map<BasicBlock*, Value*>::iterator av = avail.find(*PI);
+ DenseMap<BasicBlock*, Value*>::iterator av = avail.find(*PI);
if (av != avail.end())
avail.erase(av);
avail.insert(std::make_pair(*PI, e3));
// If there is more than one predecessor...
if (pred_begin(BB) != pred_end(BB) && ++pred_begin(BB) != pred_end(BB)) {
- std::vector<Value*> workList;
+ SmallVector<Value*, 8> workList;
workList.reserve(anticIn.size());
topo_sort(anticIn, workList);
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