|
public SetInsertPoint ( |
||
| bb | ||
| return | void | |
static void Main(string[] args)
{
var context = new LLVMContext();
var module = new Module("NoName", context);
var builder = new IRBuilder(context);
var t = builder.getInt32Ty();
var funcType = FunctionType.get(t, false);
var main = Function.Create(funcType, GlobalValue.LinkageTypes.ExternalLinkage, "main", module);
var entry = BasicBlock.Create(context, "entrypoint", main);
builder.SetInsertPoint(entry);
var hello = builder.CreateGlobalStringPtr("Hello, World!");
var putsType = FunctionType.get(builder.getInt32Ty(),
new[] { builder.getInt8Ty().getPointerTo(0) }, false);
var putsFunc = module.getOrInsertFunction("puts", putsType);
builder.CreateCall(putsFunc, hello);
var variable = builder.CreateAlloca(t);
var val = ConstantInt.get(t, 127);
builder.CreateStore(val, variable);
builder.CreateRetVoid();
var pm = new PassManager();
var os = new raw_fd_ostream("code.ll");
pm.add(Passes.createPrintModulePass(os));
pm.run(module);
os.close();
Console.ReadKey();
}
public Function CodeGen(IRBuilder builder)
{
CodeGenManager.NamedValues.Clear();
Function func = this.Proto.CodeGen(builder);
if(func == null)
return null;
// Create a new basic block to start insertion into.
BasicBlock bb = func.AppendBasicBlock("entry");
builder.SetInsertPoint(bb);
Value retVal = Body.CodeGen(builder);
if(!retVal.IsNull)
{
builder.BuildReturn(retVal);
// Validate the generated code, checking for consistency.
func.Validate(LLVMVerifierFailureAction.PrintMessageAction);
return func;
}
// Error reading body, remove function.
func.Delete();
return null;
}
public override Value CodeGen(IRBuilder builder)
{
Value startV = this.Start.CodeGen(builder);
if(startV.IsNull) return startV;
BasicBlock startBlock = builder.GetInsertPoint();
Function func = startBlock.GetParent();
BasicBlock loopBB = func.AppendBasicBlock("loop");
builder.BuildBr(loopBB);
builder.SetInsertPoint(loopBB);
Value variable = builder.BuildPhi(TypeRef.CreateDouble(), this.VarName, new PhiIncoming(startV, startBlock));
/* Within the loop, the variable is defined equal to the PHI node. If it
* shadows an existing variable, we have to restore it, so save it
* now. */
Value oldVal = Value.Null;
CodeGenManager.NamedValues.TryGetValue(this.VarName, out oldVal);
CodeGenManager.NamedValues[this.VarName] = variable;
/* Emit the body of the loop. This, like any other expr, can change the
* current BB. Note that we ignore the value computed by the body, but
* don't allow an error */
Body.CodeGen(builder);
// Emit the step value;
Value stepV = Value.Null;
if(this.Step != null)
stepV = this.Step.CodeGen(builder);
else
stepV = Value.CreateConstDouble(1);
Value nextVar = builder.BuildFAdd(variable, stepV, "nextvar");
// Compute the end condition
Value endCond = this.End.CodeGen(builder);
endCond = builder.BuildFCmp(endCond, LLVMRealPredicate.RealONE, Value.CreateConstDouble(0), "loopcond");
BasicBlock loopEndBB = builder.GetInsertPoint();
BasicBlock afterBB = func.AppendBasicBlock("afterloop");
builder.BuildCondBr(endCond, loopBB, afterBB);
builder.SetInsertPoint(afterBB);
builder.AddPhiIncoming(variable, nextVar, loopEndBB);
if(!oldVal.IsNull)
CodeGenManager.NamedValues[this.VarName] = oldVal;
return Value.CreateConstDouble(0);
}
public override Value CodeGen(IRBuilder builder)
{
Value condV = this.Cond.CodeGen(builder);
if(condV.IsNull) return condV;
condV = builder.BuildFCmp(condV, LLVMRealPredicate.RealONE,
Value.CreateConstDouble(0));
BasicBlock startBlock = builder.GetInsertPoint();
Function func = startBlock.GetParent();
BasicBlock thenBB = func.AppendBasicBlock("then");
builder.SetInsertPoint(thenBB);
Value thenV = this.Then.CodeGen(builder);
if(thenV.IsNull) return thenV;
/* Codegen of 'then' can change the current block, update then_bb for the
* phi. We create a new name because one is used for the phi node, and the
* other is used for the conditional branch. */
BasicBlock newThenBB = builder.GetInsertPoint();
// Emit else block
BasicBlock elseBB = func.AppendBasicBlock("else");
func.AppendBasicBlock(elseBB);
builder.SetInsertPoint(elseBB);
Value elseV = this.Else.CodeGen(builder);
if(elseV.IsNull) return elseV;
// Codegen of 'Else' can change the current block, update ElseBB for the PHI.
BasicBlock newElseBB = builder.GetInsertPoint();
// Emit merge block
BasicBlock mergeBB = func.AppendBasicBlock("ifcont");
func.AppendBasicBlock(mergeBB);
builder.SetInsertPoint(mergeBB);
PhiIncoming incoming = new PhiIncoming();
incoming.Add(thenV, thenBB);
incoming.Add(elseV, elseBB);
Value phi = builder.BuildPhi(TypeRef.CreateDouble(), "iftmp", incoming);
builder.SetInsertPoint(startBlock);
builder.BuildCondBr(condV, thenBB, elseBB);
builder.SetInsertPoint(thenBB);
builder.BuildBr(mergeBB);
builder.SetInsertPoint(elseBB);
builder.BuildBr(mergeBB);
builder.SetInsertPoint(mergeBB);
return phi;
}
public Function CodeGen(IRBuilder builder, PassManager passManager)
{
CodeGenManager.NamedValues.Clear();
Function func = this.Proto.CodeGen(builder);
if(func == null)
return null;
// If this is an operator, install it.
if(this.Proto.IsBinaryOp)
CodeGenManager.BinopPrecendence[Proto.OperatorName] = Proto.Precedence;
// Create a new basic block to start insertion into.
BasicBlock bb = func.AppendBasicBlock("entry");
builder.SetInsertPoint(bb);
Proto.CreateArgAllocas(func, builder);
Value retVal = Body.CodeGen(builder);
if(!retVal.IsNull)
{
builder.BuildReturn(retVal);
// Validate the generated code, checking for consistency.
func.Validate(LLVMVerifierFailureAction.PrintMessageAction);
// Optimize the function.
passManager.Run(func);
return func;
}
// Error reading body, remove function.
func.Delete();
return null;
}
public override Value CodeGen(IRBuilder builder)
{
// Output this as:
// var = alloca double
// ...
// start = startexpr
// store start -> var
// goto loop
// loop:
// ...
// bodyexpr
// ...
// loopend:
// step = stepexpr
// endcond = endexpr
//
// curvar = load var
// nextvar = curvar + step
// store nextvar -> var
// br endcond, loop, endloop
// outloop:
BasicBlock startBlock = builder.GetInsertPoint();
Function func = startBlock.GetParent();
Value alloca = builder.BuildEntryBlockAlloca(func, TypeRef.CreateDouble(), this.VarName);
Value startV = this.Start.CodeGen(builder);
if(startV.IsNull) return startV;
builder.BuildStore(startV, alloca);
BasicBlock loopBB = func.AppendBasicBlock("loop");
builder.BuildBr(loopBB);
builder.SetInsertPoint(loopBB);
/* Within the loop, the variable is defined equal to the PHI node. If it
* shadows an existing variable, we have to restore it, so save it
* now. */
Value oldVal = Value.Null;
CodeGenManager.NamedValues.TryGetValue(this.VarName, out oldVal);
CodeGenManager.NamedValues[this.VarName] = alloca;
/* Emit the body of the loop. This, like any other expr, can change the
* current BB. Note that we ignore the value computed by the body, but
* don't allow an error */
Body.CodeGen(builder);
// Emit the step value;
Value stepV = Value.Null;
if(this.Step != null)
stepV = this.Step.CodeGen(builder);
else
stepV = Value.CreateConstDouble(1);
// Compute the end condition
Value endCond = this.End.CodeGen(builder);
endCond = builder.BuildFCmp(endCond, LLVMRealPredicate.RealONE, Value.CreateConstDouble(0), "loopcond");
Value curvar = builder.BuildLoad(alloca, VarName);
Value nextVar = builder.BuildFAdd(curvar, stepV, "nextvar");
builder.BuildStore(nextVar, alloca);
BasicBlock loopEndBB = builder.GetInsertPoint();
BasicBlock afterBB = func.AppendBasicBlock("afterloop");
builder.BuildCondBr(endCond, loopBB, afterBB);
builder.SetInsertPoint(afterBB);
if(!oldVal.IsNull)
CodeGenManager.NamedValues[this.VarName] = oldVal;
else
CodeGenManager.NamedValues.Remove(this.VarName);
return Value.CreateConstDouble(0);
}
