public Function(CodeGeneratorContext genContext, FunctionDefinitionNode leaf)
{
_leaf = leaf;
// Create function type and add the function node without appending any basic blocks
// This results in a function declaration in LLVM-IR
Type[] paramTypes =
Array.ConvertAll(leaf.Parameters, param => genContext.LookupType(param.Type) !.Value);
FunctionType =
genContext.Context.FunctionType(genContext.LookupType(leaf.ReturnType) !.Value, paramTypes, false);
FunctionValue = genContext.Module.AddFunction(leaf.Name, FunctionType);
// Process the static keyword in the same manner as clang
FunctionValue.SetLinkage(leaf.IsExported
? LLVMLinkage.LLVMExternalLinkage
: LLVMLinkage.LLVMInternalLinkage);
genContext.TryGetNodeSymbol(leaf, out Symbol range);
DiFwdDecl = genContext.DiBuilder.CreateReplaceableCompositeType(
LLVMDWARFTag.subroutine_type, leaf.Name, genContext.DiFile, genContext.DiFile,
range.LLVMLine, 0, 0, 0, LLVMDIFlags.LLVMDIFlagFwdDecl, "");
}
public static Module Generate(Context context, string path, SemanticModule module,
SemanticContext semanticContext, string targetTriple, PassManagerBuilder?optBuilder, bool debugInfo,
bool columnInfo)
{
// Path information for debug info nodes
string fileName = Path.GetFileName(path);
string dirName = Path.GetDirectoryName(path);
if (dirName == null)
{
dirName = "/";
}
else if (dirName.Length == 0)
{
dirName = ".";
}
// Create module and file-level debug info nodes
using CodeGeneratorContext genContext = new CodeGeneratorContext(context, module, semanticContext, fileName,
dirName, targetTriple, optBuilder != null, debugInfo, columnInfo);
// Enum pass
foreach (EnumNode enumNode in genContext.ParseModule.Enums)
{
Metadata[] enumerators = new Metadata[enumNode.Declarations.Count];
for (int i = 0, ilen = enumNode.Declarations.Count; i < ilen; ++i)
{
var enumeration = enumNode.Declarations[i];
enumerators[i] = genContext.DiBuilder.CreateEnumerator(enumeration.Name, i, false);
}
genContext.TryGetNodeSymbol(enumNode, out Symbol range);
genContext.DiBuilder.CreateEnumerationType(genContext.DiFile,
(enumNode.IsExported ? "export." : "") + $"enum.{fileName}.{range.LLVMLine}", genContext.DiFile,
range.LLVMLine, genContext.DiBuilder.Int32Type.GetTypeSizeInBits(),
genContext.DiBuilder.Int32Type.GetTypeAlignInBits(), enumerators, genContext.DiBuilder.Int32Type);
}
// Struct pass
foreach (StructNode structNode in genContext.ParseModule.Structs)
{
genContext.EnsureStruct(structNode);
}
// Declaration pass
foreach (FunctionDefinitionNode function in genContext.ParseModule.Functions)
{
genContext.RegisterDefinedFunction(function);
}
// Definition pass
foreach (FunctionDefinitionNode function in genContext.ParseModule.Functions)
{
CodeGeneratorContext.Function ctxFunction = genContext.GetFunctionDefinition(function);
using Builder builder = genContext.Context.CreateBuilder();
FunctionCodeGenVisitor functionCodeGenVisitor = new FunctionCodeGenVisitor(genContext, ctxFunction,
builder, ctxFunction.StartDefinition(genContext, builder));
builder.PositionAtEnd(functionCodeGenVisitor._basicBlock);
function.Body.VisitStatements(functionCodeGenVisitor);
if (genContext.DebugInfo)
{
// TODO: Use the body end rather than the function end
genContext.TryGetNodeSymbol(function, out Symbol range);
Metadata location = genContext.Context.CreateDebugLocation(range.End.Line + 1,
genContext.ColumnInfo ? range.End.Column + 1 : 0, ctxFunction.DiFunctionDef,
Metadata.Null);
builder.SetCurrentDebugLocation(location);
}
// If we still have a valid insert block, this function did not end with a return; Insert one now
if (builder.InsertBlock.IsValid)
{
if (ctxFunction.ReturnBlock != null)
{
builder.BuildBr(ctxFunction.ReturnBlock.Value);
}
else
{
builder.BuildRetVoid();
}
}
if (ctxFunction.ReturnBlock != null && ctxFunction.RetvalStorage != null)
{
ctxFunction.FunctionValue.AppendExistingBasicBlock(ctxFunction.ReturnBlock.Value);
builder.PositionAtEnd(ctxFunction.ReturnBlock.Value);
Value retVal = builder.BuildLoad(ctxFunction.RetvalStorage.Value);
builder.BuildRet(retVal);
}
}
// Remove unused metadata nodes for undefined functions
genContext.FinalizeFunctions();
// Finalize debug info
genContext.DiBuilder.BuilderFinalize();
// Run optimization passes on functions and module if a builder is supplied
if (optBuilder != null)
{
using ModulePassManager modulePassManager = new ModulePassManager(optBuilder);
using FunctionPassManager functionPassManager = new FunctionPassManager(genContext.Module, optBuilder);
functionPassManager.Initialize();
foreach (var function in genContext.DefinedFunctions)
{
functionPassManager.Run(function.Value.FunctionValue);
}
functionPassManager.FinalizeFunctionPassManager();
modulePassManager.Run(genContext.Module);
}
// Done with everything in CodeGeneratorContext besides the Module
return(genContext.Module);
}
/// <summary>
/// Add entry basic block to this function and fill in additional debug info.
/// If not called, this is a function declaration.
/// </summary>
/// <param name="genContext"></param>
/// <param name="builder"></param>
/// <returns>Entry basic block</returns>
public BasicBlock StartDefinition(CodeGeneratorContext genContext, Builder builder)
{
BasicBlock basicBlock = genContext.Context.AppendBasicBlock(FunctionValue, "entry");
builder.PositionAtEnd(basicBlock);
// Build return value storage if necessary
Type returnType = FunctionType.ReturnType;
if (returnType.Kind != LLVMTypeKind.LLVMVoidTypeKind)
{
ReturnBlock = genContext.Context.CreateBasicBlock("return");
RetvalStorage = builder.BuildAlloca(returnType, "retval");
}
// Visit all declaration nodes and create storage (parameters and variables)
StackLayoutGenerator layoutGenerator = new StackLayoutGenerator(new IndexTypeSizeManager());
layoutGenerator.VisitFunctionDefinition(_leaf);
FunctionStackLayout layout = layoutGenerator.GetLayout();
foreach (var v in layout.Variables)
{
Type varType = genContext.LookupType(v.Key.Type) !.Value;
Value varStorage = builder.BuildAlloca(varType, v.Key.Name);
VariableValues[v.Key] = varStorage;
}
// Emit store instruction for return value
if (RetvalStorage != null && !returnType.IsStructType())
{
builder.BuildStore(Value.ConstInt(returnType, 0, true), RetvalStorage.Value);
}
// Emit store instructions for parameters
Value[] funcParams = FunctionValue.Params;
for (int i = 0, ilen = funcParams.Length; i < ilen; ++i)
{
DeclarationNode parameter = _leaf.Parameters[i];
Value paramValue = funcParams[i];
VariableValues.TryGetValue(parameter, out Value varStorage);
varStorage.SetName($"{parameter.Name}.addr");
builder.BuildStore(paramValue, varStorage);
paramValue.SetName(parameter.Name);
}
// Create subroutine type debug info
genContext.TryGetNodeSymbol(_leaf, out Symbol range);
Metadata subroutineType = genContext.DiBuilder.CreateSubroutineType(genContext.DiFile,
Array.ConvertAll(_leaf.Parameters, param => genContext.LookupDiType(param.Type) !.Value),
LLVMDIFlags.LLVMDIFlagZero);
Metadata funcLocation = genContext.Context.CreateDebugLocation(range.LLVMLine,
genContext.ColumnInfo ? range.LLVMColumn : 0, DiFwdDecl, Metadata.Null);
// Create subroutine debug info and substitute over forward declaration
DiFunctionDef = genContext.DiBuilder.CreateFunction(genContext.DiFile, _leaf.Name, _leaf.Name,
genContext.DiFile, range.LLVMLine, subroutineType, true, true, range.LLVMLine,
LLVMDIFlags.LLVMDIFlagZero, false);
DiFwdDecl.ReplaceAllUsesWith(DiFunctionDef);
// Create llvm.dbg.declare calls for each parameter's storage
if (genContext.DebugInfo)
{
Metadata paramExpression = genContext.DiBuilder.CreateExpression();
for (int i = 0, ilen = _leaf.Parameters.Length; i < ilen; ++i)
{
DeclarationNode parameter = _leaf.Parameters[i];
genContext.TryGetNodeSymbol(parameter, out Symbol paramRange);
Metadata paramType = genContext.LookupDiType(parameter.Type) !.Value;
Metadata paramMetadata = genContext.DiBuilder.CreateParameterVariable(DiFunctionDef,
parameter.Name, (uint)i + 1, genContext.DiFile, paramRange.LLVMLine, paramType, true,
LLVMDIFlags.LLVMDIFlagZero);
VariableValues.TryGetValue(parameter, out Value varStorage);
genContext.DiBuilder.InsertDeclareAtEnd(varStorage, paramMetadata, paramExpression,
funcLocation, basicBlock);
}
}
// Associate debug info nodes with function
FunctionValue.SetFuncSubprogram(DiFunctionDef);
return(basicBlock);
}