Add support for performing GVNPRE on cast instructions, and add a testcase for this.

llvm-svn: 37856
This commit is contained in:
Owen Anderson 2007-07-03 18:37:08 +00:00
parent 11f9d1b7ee
commit 59bd053fc5
2 changed files with 133 additions and 18 deletions

View File

@ -629,8 +629,41 @@ Value* GVNPRE::phi_translate(Value* V, BasicBlock* pred, BasicBlock* succ) {
if (V == 0)
return 0;
// Unary Operations
if (isa<CastInst>(V)) {
User* U = cast<User>(V);
Value* newOp1 = 0;
if (isa<Instruction>(U->getOperand(0)))
newOp1 = phi_translate(U->getOperand(0), pred, succ);
else
newOp1 = U->getOperand(0);
if (newOp1 == 0)
return 0;
if (newOp1 != U->getOperand(0)) {
Instruction* newVal = 0;
if (CastInst* C = dyn_cast<CastInst>(U))
newVal = CastInst::create(C->getOpcode(),
newOp1, C->getType(),
C->getName()+".expr");
uint32_t v = VN.lookup_or_add(newVal);
Value* leader = find_leader(availableOut[pred], v);
if (leader == 0) {
createdExpressions.push_back(newVal);
return newVal;
} else {
VN.erase(newVal);
delete newVal;
return leader;
}
}
// Binary Operations
if (isa<BinaryOperator>(V) || isa<CmpInst>(V) ||
} if (isa<BinaryOperator>(V) || isa<CmpInst>(V) ||
isa<ExtractElementInst>(V)) {
User* U = cast<User>(V);
@ -783,8 +816,22 @@ void GVNPRE::clean(SmallPtrSet<Value*, 16>& set, BitVector& presentInSet) {
for (unsigned i = 0; i < worklist.size(); ++i) {
Value* v = worklist[i];
// Handle unary ops
if (isa<CastInst>(v)) {
User* U = cast<User>(v);
bool lhsValid = !isa<Instruction>(U->getOperand(0));
lhsValid |= presentInSet.test(VN.lookup(U->getOperand(0)));
if (lhsValid)
lhsValid = !dependsOnInvoke(U->getOperand(0));
if (!lhsValid) {
set.erase(U);
presentInSet.flip(VN.lookup(U));
}
// Handle binary ops
if (isa<BinaryOperator>(v) || isa<CmpInst>(v) ||
} else if (isa<BinaryOperator>(v) || isa<CmpInst>(v) ||
isa<ExtractElementInst>(v)) {
User* U = cast<User>(v);
@ -844,8 +891,22 @@ void GVNPRE::topo_sort(SmallPtrSet<Value*, 16>& set, std::vector<Value*>& vec) {
while (!stack.empty()) {
Value* e = stack.back();
// Handle unary ops
if (isa<CastInst>(e)) {
User* U = cast<User>(e);
Value* l = find_leader(set, VN.lookup(U->getOperand(0)));
if (l != 0 && isa<Instruction>(l) &&
visited.count(l) == 0)
stack.push_back(l);
else {
vec.push_back(e);
visited.insert(e);
stack.pop_back();
}
// Handle binary ops
if (isa<BinaryOperator>(e) || isa<CmpInst>(e) ||
} else if (isa<BinaryOperator>(e) || isa<CmpInst>(e) ||
isa<ExtractElementInst>(e)) {
User* U = cast<User>(e);
Value* l = find_leader(set, VN.lookup(U->getOperand(0)));
@ -935,7 +996,8 @@ bool GVNPRE::elimination() {
if (isa<BinaryOperator>(BI) || isa<CmpInst>(BI) ||
isa<ShuffleVectorInst>(BI) || isa<InsertElementInst>(BI) ||
isa<ExtractElementInst>(BI) || isa<SelectInst>(BI)) {
isa<ExtractElementInst>(BI) || isa<SelectInst>(BI) ||
isa<CastInst>(BI)) {
Value *leader = find_leader(availableOut[BB], VN.lookup(BI));
if (leader != 0)
@ -991,6 +1053,26 @@ void GVNPRE::buildsets_availout(BasicBlock::iterator I,
currPhis.insert(p);
// Handle unary ops
} else if (isa<CastInst>(I)) {
User* U = cast<User>(I);
Value* leftValue = U->getOperand(0);
unsigned num = VN.lookup_or_add(U);
expNumbers.resize(VN.size());
availNumbers.resize(VN.size());
if (isa<Instruction>(leftValue))
if (!expNumbers.test(VN.lookup(leftValue))) {
currExps.insert(leftValue);
expNumbers.set(VN.lookup(leftValue));
}
if (!expNumbers.test(VN.lookup(U))) {
currExps.insert(U);
expNumbers.set(num);
}
// Handle binary ops
} else if (isa<BinaryOperator>(I) || isa<CmpInst>(I) ||
isa<ExtractElementInst>(I)) {
@ -1266,21 +1348,31 @@ void GVNPRE::insertion_pre(Value* e, BasicBlock* BB,
isa<ShuffleVectorInst>(U->getOperand(0)) ||
isa<ExtractElementInst>(U->getOperand(0)) ||
isa<InsertElementInst>(U->getOperand(0)) ||
isa<SelectInst>(U->getOperand(0)))
isa<SelectInst>(U->getOperand(0)) ||
isa<CastInst>(U->getOperand(0)))
s1 = find_leader(availableOut[*PI], VN.lookup(U->getOperand(0)));
else
s1 = U->getOperand(0);
Value* s2 = 0;
if (isa<BinaryOperator>(U->getOperand(1)) ||
isa<CmpInst>(U->getOperand(1)) ||
isa<ShuffleVectorInst>(U->getOperand(1)) ||
isa<ExtractElementInst>(U->getOperand(1)) ||
isa<InsertElementInst>(U->getOperand(1)) ||
isa<SelectInst>(U->getOperand(1)))
s2 = find_leader(availableOut[*PI], VN.lookup(U->getOperand(1)));
else
s2 = U->getOperand(1);
if (isa<BinaryOperator>(U) ||
isa<CmpInst>(U) ||
isa<ShuffleVectorInst>(U) ||
isa<ExtractElementInst>(U) ||
isa<InsertElementInst>(U) ||
isa<SelectInst>(U))
if (isa<BinaryOperator>(U->getOperand(1)) ||
isa<CmpInst>(U->getOperand(1)) ||
isa<ShuffleVectorInst>(U->getOperand(1)) ||
isa<ExtractElementInst>(U->getOperand(1)) ||
isa<InsertElementInst>(U->getOperand(1)) ||
isa<SelectInst>(U->getOperand(1)) ||
isa<CastInst>(U->getOperand(1))) {
s2 = find_leader(availableOut[*PI], VN.lookup(U->getOperand(1)));
} else {
s2 = U->getOperand(1);
}
// Ternary Operators
Value* s3 = 0;
@ -1292,10 +1384,12 @@ void GVNPRE::insertion_pre(Value* e, BasicBlock* BB,
isa<ShuffleVectorInst>(U->getOperand(2)) ||
isa<ExtractElementInst>(U->getOperand(2)) ||
isa<InsertElementInst>(U->getOperand(2)) ||
isa<SelectInst>(U->getOperand(2)))
isa<SelectInst>(U->getOperand(2)) ||
isa<CastInst>(U->getOperand(2))) {
s3 = find_leader(availableOut[*PI], VN.lookup(U->getOperand(2)));
else
} else {
s3 = U->getOperand(2);
}
Value* newVal = 0;
if (BinaryOperator* BO = dyn_cast<BinaryOperator>(U))
@ -1319,6 +1413,10 @@ void GVNPRE::insertion_pre(Value* e, BasicBlock* BB,
newVal = new SelectInst(S->getCondition(), S->getTrueValue(),
S->getFalseValue(), S->getName()+".gvnpre",
(*PI)->getTerminator());
else if (CastInst* C = dyn_cast<CastInst>(U))
newVal = CastInst::create(C->getOpcode(), s1, C->getType(),
C->getName()+".gvnpre",
(*PI)->getTerminator());
VN.add(newVal, VN.lookup(U));
@ -1365,7 +1463,7 @@ unsigned GVNPRE::insertion_mergepoint(std::vector<Value*>& workList,
if (isa<BinaryOperator>(e) || isa<CmpInst>(e) ||
isa<ExtractElementInst>(e) || isa<InsertElementInst>(e) ||
isa<ShuffleVectorInst>(e) || isa<SelectInst>(e)) {
isa<ShuffleVectorInst>(e) || isa<SelectInst>(e) || isa<CastInst>(e)) {
if (find_leader(availableOut[D->getIDom()->getBlock()],
VN.lookup(e)) != 0)
continue;

View File

@ -0,0 +1,17 @@
; RUN: llvm-as < %s | opt -gvnpre | llvm-dis | grep b.gvnpre
define i32 @extract() {
entry: ; preds = %cond_false, %entry
br i1 true, label %cond_true, label %cond_false
cond_true:
br label %end
cond_false:
%a = sext i16 0 to i32
br label %end
end:
%b = sext i16 0 to i32
ret i32 %b
}