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-rw-r--r--lib/Transforms/Scalar/EarlyCSE.cpp80
1 files changed, 40 insertions, 40 deletions
diff --git a/lib/Transforms/Scalar/EarlyCSE.cpp b/lib/Transforms/Scalar/EarlyCSE.cpp
index f3c92d6..9759549 100644
--- a/lib/Transforms/Scalar/EarlyCSE.cpp
+++ b/lib/Transforms/Scalar/EarlyCSE.cpp
@@ -39,7 +39,7 @@ static unsigned getHash(const void *V) {
}
//===----------------------------------------------------------------------===//
-// SimpleValue
+// SimpleValue
//===----------------------------------------------------------------------===//
namespace {
@@ -47,16 +47,16 @@ namespace {
/// scoped hash table.
struct SimpleValue {
Instruction *Inst;
-
+
SimpleValue(Instruction *I) : Inst(I) {
assert((isSentinel() || canHandle(I)) && "Inst can't be handled!");
}
-
+
bool isSentinel() const {
return Inst == DenseMapInfo<Instruction*>::getEmptyKey() ||
Inst == DenseMapInfo<Instruction*>::getTombstoneKey();
}
-
+
static bool canHandle(Instruction *Inst) {
// This can only handle non-void readnone functions.
if (CallInst *CI = dyn_cast<CallInst>(Inst))
@@ -90,7 +90,7 @@ template<> struct DenseMapInfo<SimpleValue> {
unsigned DenseMapInfo<SimpleValue>::getHashValue(SimpleValue Val) {
Instruction *Inst = Val.Inst;
-
+
// Hash in all of the operands as pointers.
unsigned Res = 0;
for (unsigned i = 0, e = Inst->getNumOperands(); i != e; ++i)
@@ -126,13 +126,13 @@ bool DenseMapInfo<SimpleValue>::isEqual(SimpleValue LHS, SimpleValue RHS) {
if (LHS.isSentinel() || RHS.isSentinel())
return LHSI == RHSI;
-
+
if (LHSI->getOpcode() != RHSI->getOpcode()) return false;
return LHSI->isIdenticalTo(RHSI);
}
//===----------------------------------------------------------------------===//
-// CallValue
+// CallValue
//===----------------------------------------------------------------------===//
namespace {
@@ -140,21 +140,21 @@ namespace {
/// the scoped hash table.
struct CallValue {
Instruction *Inst;
-
+
CallValue(Instruction *I) : Inst(I) {
assert((isSentinel() || canHandle(I)) && "Inst can't be handled!");
}
-
+
bool isSentinel() const {
return Inst == DenseMapInfo<Instruction*>::getEmptyKey() ||
Inst == DenseMapInfo<Instruction*>::getTombstoneKey();
}
-
+
static bool canHandle(Instruction *Inst) {
// Don't value number anything that returns void.
if (Inst->getType()->isVoidTy())
return false;
-
+
CallInst *CI = dyn_cast<CallInst>(Inst);
if (CI == 0 || !CI->onlyReadsMemory())
return false;
@@ -168,7 +168,7 @@ namespace llvm {
template<> struct isPodLike<CallValue> {
static const bool value = true;
};
-
+
template<> struct DenseMapInfo<CallValue> {
static inline CallValue getEmptyKey() {
return DenseMapInfo<Instruction*>::getEmptyKey();
@@ -189,7 +189,7 @@ unsigned DenseMapInfo<CallValue>::getHashValue(CallValue Val) {
"Cannot value number calls with metadata operands");
Res ^= getHash(Inst->getOperand(i)) << (i & 0xF);
}
-
+
// Mix in the opcode.
return (Res << 1) ^ Inst->getOpcode();
}
@@ -203,11 +203,11 @@ bool DenseMapInfo<CallValue>::isEqual(CallValue LHS, CallValue RHS) {
//===----------------------------------------------------------------------===//
-// EarlyCSE pass.
+// EarlyCSE pass.
//===----------------------------------------------------------------------===//
namespace {
-
+
/// EarlyCSE - This pass does a simple depth-first walk over the dominator
/// tree, eliminating trivially redundant instructions and using instsimplify
/// to canonicalize things as it goes. It is intended to be fast and catch
@@ -223,14 +223,14 @@ public:
ScopedHashTableVal<SimpleValue, Value*> > AllocatorTy;
typedef ScopedHashTable<SimpleValue, Value*, DenseMapInfo<SimpleValue>,
AllocatorTy> ScopedHTType;
-
+
/// AvailableValues - This scoped hash table contains the current values of
/// all of our simple scalar expressions. As we walk down the domtree, we
/// look to see if instructions are in this: if so, we replace them with what
/// we find, otherwise we insert them so that dominated values can succeed in
/// their lookup.
ScopedHTType *AvailableValues;
-
+
/// AvailableLoads - This scoped hash table contains the current values
/// of loads. This allows us to get efficient access to dominating loads when
/// we have a fully redundant load. In addition to the most recent load, we
@@ -243,15 +243,15 @@ public:
typedef ScopedHashTable<Value*, std::pair<Value*, unsigned>,
DenseMapInfo<Value*>, LoadMapAllocator> LoadHTType;
LoadHTType *AvailableLoads;
-
+
/// AvailableCalls - This scoped hash table contains the current values
/// of read-only call values. It uses the same generation count as loads.
typedef ScopedHashTable<CallValue, std::pair<Value*, unsigned> > CallHTType;
CallHTType *AvailableCalls;
-
+
/// CurrentGeneration - This is the current generation of the memory value.
unsigned CurrentGeneration;
-
+
static char ID;
explicit EarlyCSE() : FunctionPass(ID) {
initializeEarlyCSEPass(*PassRegistry::getPassRegistry());
@@ -326,7 +326,7 @@ private:
};
bool processNode(DomTreeNode *Node);
-
+
// This transformation requires dominator postdominator info
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<DominatorTree>();
@@ -350,7 +350,7 @@ INITIALIZE_PASS_END(EarlyCSE, "early-cse", "Early CSE", false, false)
bool EarlyCSE::processNode(DomTreeNode *Node) {
BasicBlock *BB = Node->getBlock();
-
+
// If this block has a single predecessor, then the predecessor is the parent
// of the domtree node and all of the live out memory values are still current
// in this block. If this block has multiple predecessors, then they could
@@ -359,20 +359,20 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
// predecessors.
if (BB->getSinglePredecessor() == 0)
++CurrentGeneration;
-
+
/// LastStore - Keep track of the last non-volatile store that we saw... for
/// as long as there in no instruction that reads memory. If we see a store
/// to the same location, we delete the dead store. This zaps trivial dead
/// stores which can occur in bitfield code among other things.
StoreInst *LastStore = 0;
-
+
bool Changed = false;
// See if any instructions in the block can be eliminated. If so, do it. If
// not, add them to AvailableValues.
for (BasicBlock::iterator I = BB->begin(), E = BB->end(); I != E; ) {
Instruction *Inst = I++;
-
+
// Dead instructions should just be removed.
if (isInstructionTriviallyDead(Inst)) {
DEBUG(dbgs() << "EarlyCSE DCE: " << *Inst << '\n');
@@ -381,7 +381,7 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
++NumSimplify;
continue;
}
-
+
// If the instruction can be simplified (e.g. X+0 = X) then replace it with
// its simpler value.
if (Value *V = SimplifyInstruction(Inst, TD, TLI, DT)) {
@@ -392,7 +392,7 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
++NumSimplify;
continue;
}
-
+
// If this is a simple instruction that we can value number, process it.
if (SimpleValue::canHandle(Inst)) {
// See if the instruction has an available value. If so, use it.
@@ -404,12 +404,12 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
++NumCSE;
continue;
}
-
+
// Otherwise, just remember that this value is available.
AvailableValues->insert(Inst, Inst);
continue;
}
-
+
// If this is a non-volatile load, process it.
if (LoadInst *LI = dyn_cast<LoadInst>(Inst)) {
// Ignore volatile loads.
@@ -417,7 +417,7 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
LastStore = 0;
continue;
}
-
+
// If we have an available version of this load, and if it is the right
// generation, replace this instruction.
std::pair<Value*, unsigned> InVal =
@@ -431,18 +431,18 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
++NumCSELoad;
continue;
}
-
+
// Otherwise, remember that we have this instruction.
AvailableLoads->insert(Inst->getOperand(0),
std::pair<Value*, unsigned>(Inst, CurrentGeneration));
LastStore = 0;
continue;
}
-
+
// If this instruction may read from memory, forget LastStore.
if (Inst->mayReadFromMemory())
LastStore = 0;
-
+
// If this is a read-only call, process it.
if (CallValue::canHandle(Inst)) {
// If we have an available version of this call, and if it is the right
@@ -457,19 +457,19 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
++NumCSECall;
continue;
}
-
+
// Otherwise, remember that we have this instruction.
AvailableCalls->insert(Inst,
std::pair<Value*, unsigned>(Inst, CurrentGeneration));
continue;
}
-
+
// Okay, this isn't something we can CSE at all. Check to see if it is
// something that could modify memory. If so, our available memory values
// cannot be used so bump the generation count.
if (Inst->mayWriteToMemory()) {
++CurrentGeneration;
-
+
if (StoreInst *SI = dyn_cast<StoreInst>(Inst)) {
// We do a trivial form of DSE if there are two stores to the same
// location with no intervening loads. Delete the earlier store.
@@ -483,7 +483,7 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
LastStore = 0;
continue;
}
-
+
// Okay, we just invalidated anything we knew about loaded values. Try
// to salvage *something* by remembering that the stored value is a live
// version of the pointer. It is safe to forward from volatile stores
@@ -491,7 +491,7 @@ bool EarlyCSE::processNode(DomTreeNode *Node) {
// the store.
AvailableLoads->insert(SI->getPointerOperand(),
std::pair<Value*, unsigned>(SI->getValueOperand(), CurrentGeneration));
-
+
// Remember that this was the last store we saw for DSE.
if (SI->isSimple())
LastStore = SI;
@@ -509,7 +509,7 @@ bool EarlyCSE::runOnFunction(Function &F) {
TD = getAnalysisIfAvailable<TargetData>();
TLI = &getAnalysis<TargetLibraryInfo>();
DT = &getAnalysis<DominatorTree>();
-
+
// Tables that the pass uses when walking the domtree.
ScopedHTType AVTable;
AvailableValues = &AVTable;
@@ -517,7 +517,7 @@ bool EarlyCSE::runOnFunction(Function &F) {
AvailableLoads = &LoadTable;
CallHTType CallTable;
AvailableCalls = &CallTable;
-
+
CurrentGeneration = 0;
bool Changed = false;
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