public OptionalValue <BitcodeModule> Generate(IAstNode ast)
{
ast.ValidateNotNull(nameof(ast));
ast.Accept(this);
if (AnonymousFunctions.Count > 0)
{
var mainFunction = Module.CreateFunction("main", Context.GetFunctionType(Context.VoidType));
var block = mainFunction.AppendBasicBlock("entry");
var irBuilder = new InstructionBuilder(block);
var printdFunc = Module.CreateFunction("printd", Context.GetFunctionType(Context.DoubleType, Context.DoubleType));
foreach (var anonFunc in AnonymousFunctions)
{
var value = irBuilder.Call(anonFunc);
irBuilder.Call(printdFunc, value);
}
irBuilder.Return( );
// Use always inline and Dead Code Elimination module passes to inline all of the
// anonymous functions. This effectively strips all the calls just generated for main()
// and inlines each of the anonymous functions directly into main, dropping the now
// unused original anonymous functions all while retaining all of the original source
// debug information locations.
using var mpm = new ModulePassManager( );
mpm.AddAlwaysInlinerPass( )
.AddGlobalDCEPass( )
.Run(Module);
Module.DIBuilder.Finish( );
}
return(OptionalValue.Create(Module));
}
public static void Main(string[] args)
{
#region CommandlineArguments
if (args.Length < 2 || args.Length > 3)
{
ShowUsage( );
return;
}
string outputPath = args.Length == 3 ? args[2] : Environment.CurrentDirectory;
string srcPath = args[1];
if (!File.Exists(srcPath))
{
Console.Error.WriteLine("Src file not found: '{0}'", srcPath);
return;
}
srcPath = Path.GetFullPath(srcPath);
#endregion
using var libLLVM = InitializeLLVM( );
#region TargetDetailsSelection
switch (args[0].ToUpperInvariant( ))
{
case "M3":
TargetDetails = new CortexM3Details(libLLVM);
break;
case "X64":
TargetDetails = new X64Details(libLLVM);
break;
default:
ShowUsage( );
return;
}
string moduleName = $"test_{TargetDetails.ShortName}.bc";
#endregion
#region CreatingModule
using var context = new Context( );
using var module = context.CreateBitcodeModule(moduleName, SourceLanguage.C99, srcPath, VersionIdentString);
module.SourceFileName = Path.GetFileName(srcPath);
module.TargetTriple = TargetDetails.TargetMachine.Triple;
module.Layout = TargetDetails.TargetMachine.TargetData;
Debug.Assert(!(module.DICompileUnit is null), "Expected module with non-null compile unit");
TargetDependentAttributes = TargetDetails.BuildTargetDependentFunctionAttributes(context);
#endregion
var diFile = module.DIBuilder.CreateFile(srcPath);
#region CreatingBasicTypesWithDebugInfo
// Create basic types used in this compilation
var i32 = new DebugBasicType(module.Context.Int32Type, module, "int", DiTypeKind.Signed);
var f32 = new DebugBasicType(module.Context.FloatType, module, "float", DiTypeKind.Float);
var voidType = DebugType.Create <ITypeRef, DIType>(module.Context.VoidType, null);
var i32Array_0_32 = i32.CreateArrayType(module, 0, 32);
#endregion
#region CreatingStructureTypes
// create the LLVM structure type and body with full debug information
var fooBody = new[]
{
new DebugMemberInfo(0, "a", diFile, 3, i32),
new DebugMemberInfo(1, "b", diFile, 4, f32),
new DebugMemberInfo(2, "c", diFile, 5, i32Array_0_32),
};
var fooType = new DebugStructType(module, "struct.foo", module.DICompileUnit, "foo", diFile, 1, DebugInfoFlags.None, fooBody);
#endregion
#region CreatingGlobalsAndMetadata
// add global variables and constants
var constArray = ConstantArray.From(i32, 32, module.Context.CreateConstant(3), module.Context.CreateConstant(4));
var barValue = module.Context.CreateNamedConstantStruct(fooType
, module.Context.CreateConstant(1)
, module.Context.CreateConstant(2.0f)
, constArray
);
var bar = module.AddGlobal(fooType, false, 0, barValue, "bar");
bar.Alignment = module.Layout.AbiAlignmentOf(fooType);
bar.AddDebugInfo(module.DIBuilder.CreateGlobalVariableExpression(module.DICompileUnit, "bar", string.Empty, diFile, 8, fooType.DIType, false, null));
var baz = module.AddGlobal(fooType, false, Linkage.Common, Constant.NullValueFor(fooType), "baz");
baz.Alignment = module.Layout.AbiAlignmentOf(fooType);
baz.AddDebugInfo(module.DIBuilder.CreateGlobalVariableExpression(module.DICompileUnit, "baz", string.Empty, diFile, 9, fooType.DIType, false, null));
// add module flags and compiler identifiers...
// this can technically occur at any point, though placing it here makes
// comparing against clang generated files easier
AddModuleFlags(module);
#endregion
#region CreatingQualifiedTypes
// create types for function args
var constFoo = module.DIBuilder.CreateQualifiedType(fooType.DIType, QualifiedTypeTag.Const);
var fooPtr = new DebugPointerType(fooType, module);
#endregion
// Create the functions
// NOTE: The declaration ordering is reversed from that of the sample code file (test.c)
// However, this is what Clang ends up doing for some reason so it is
// replicated here to aid in comparing the generated LL files.
IrFunction doCopyFunc = DeclareDoCopyFunc(module, diFile, voidType);
IrFunction copyFunc = DeclareCopyFunc(module, diFile, voidType, constFoo, fooPtr);
CreateCopyFunctionBody(module, copyFunc, diFile, fooType, fooPtr, constFoo);
CreateDoCopyFunctionBody(module, doCopyFunc, fooType, bar, baz, copyFunc);
// finalize the debug information
// all temporaries must be replaced by now, this resolves any remaining
// forward declarations and marks the builder to prevent adding any
// nodes that are not completely resolved.
module.DIBuilder.Finish( );
// verify the module is still good and print any errors found
if (!module.Verify(out string msg))
{
Console.Error.WriteLine("ERROR: {0}", msg);
}
else
{
// test optimization works, but don't save it as that makes it harder to do a compare with official clang builds
{// force a GC to verify callback delegate for diagnostics is still valid, this is for test only and wouldn't
// normally be done in production code.
GC.Collect(GC.MaxGeneration);
using var modForOpt = module.Clone( );
// NOTE:
// The ordering of passes can matter depending on the pass, and passes may be added more than once
// the caller has full control of ordering, this is just a sample of effectively randomly picked
// passes and not necessarily a reflection of any particular use case.
using var pm = new ModulePassManager( );
pm.AddAlwaysInlinerPass( )
.AddAggressiveDCEPass( )
.AddArgumentPromotionPass( )
.AddBasicAliasAnalysisPass( )
.AddBitTrackingDCEPass( )
.AddCFGSimplificationPass( )
.AddConstantMergePass( )
.AddConstantPropagationPass( )
.AddFunctionInliningPass( )
.AddGlobalOptimizerPass( )
.AddInstructionCombiningPass( )
.Run(modForOpt);
}
// Module is good, so generate the output files
module.WriteToFile(Path.Combine(outputPath, "test.bc"));
File.WriteAllText(Path.Combine(outputPath, "test.ll"), module.WriteToString( ));
TargetDetails.TargetMachine.EmitToFile(module, Path.Combine(outputPath, "test.o"), CodeGenFileType.ObjectFile);
TargetDetails.TargetMachine.EmitToFile(module, Path.Combine(outputPath, "test.s"), CodeGenFileType.AssemblySource);
Console.WriteLine("Generated test.bc, test.ll, test.o, and test.s");
}
}