private static Function DeclareCopyFunc(BitcodeModule module
, DIFile diFile
, IDebugType <ITypeRef, DIType> voidType
, DIDerivedType constFoo
, DebugPointerType fooPtr
)
{
// Since the first parameter is passed by value
// using the pointer + alloca + memcopy pattern, the actual
// source, and therefore debug, signature is NOT a pointer.
// However, that usage would create a signature with two
// pointers as the arguments, which doesn't match the source
// To get the correct debug info signature this inserts an
// explicit DebugType<> that overrides the default behavior
// to pair the LLVM pointer type with the original source type.
var copySig = module.Context.CreateFunctionType(module.DIBuilder
, voidType
, DebugType.Create(fooPtr, constFoo)
, fooPtr
);
var copyFunc = module.CreateFunction(scope: diFile
, name: "copy"
, linkageName: null
, file: diFile
, line: 11
, signature: copySig
, isLocalToUnit: true
, isDefinition: true
, scopeLine: 14
, debugFlags: DebugInfoFlags.Prototyped
, isOptimized: false
).Linkage(Linkage.Internal) // static function
.AddAttributes(FunctionAttributeIndex.Function, AttributeKind.NoUnwind, AttributeKind.NoInline, AttributeKind.OptimizeNone)
.AddAttributes(FunctionAttributeIndex.Function, TargetDependentAttributes);
TargetDetails.AddABIAttributesForByValueStructure(copyFunc, 0);
return(copyFunc);
}
/// <summary>Creates a test LLVM module with debug information</summary>
/// <param name="args">ignored</param>
/// <remarks>
/// <code language="c" title="Example code generated" source="test.c" />
/// </remarks>
public static void Main(string[] args)
{
TargetDetails = new CortexM3Details();
string srcPath = args[0];
if (!File.Exists(srcPath))
{
Console.Error.WriteLine("Src file not found: '{0}'", srcPath);
return;
}
srcPath = Path.GetFullPath(srcPath);
string moduleName = $"test_{TargetDetails.ShortName}.bc";
using (StaticState.InitializeLLVM())
{
StaticState.RegisterAll( );
var target = Target.FromTriple(TargetDetails.Triple);
using (var context = new Context( ))
using (var targetMachine = target.CreateTargetMachine(TargetDetails.Triple, TargetDetails.Cpu, TargetDetails.Features, CodeGenOpt.Aggressive, Reloc.Default, CodeModel.Small))
using (var module = new BitcodeModule(context, moduleName))
{
module.SourceFileName = Path.GetFileName(srcPath);
TargetDependentAttributes = TargetDetails.BuildTargetDependentFunctionAttributes(context);
var targetData = targetMachine.TargetData;
module.TargetTriple = targetMachine.Triple;
module.Layout = targetMachine.TargetData;
// create compile unit and file as the top level scope for everything
var cu = module.DIBuilder.CreateCompileUnit(SourceLanguage.C99
, Path.GetFileName(srcPath)
, Path.GetDirectoryName(srcPath)
, VersionIdentString
, false
, string.Empty
, 0
);
var diFile = module.DIBuilder.CreateFile(srcPath);
// 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(module.Context.VoidType, ( DIType )null);
var i32Array_0_32 = i32.CreateArrayType(module, 0, 32);
// create the LLVM structure type and body with full debug information
#pragma warning disable SA1500 // "Warning SA1500 Braces for multi - line statements must not share line" (simple table format)
var fooBody = new[]
{ new DebugMemberInfo {
File = diFile, Line = 3, Name = "a", DebugType = i32, Index = 0
}
, new DebugMemberInfo {
File = diFile, Line = 4, Name = "b", DebugType = f32, Index = 1
}
, new DebugMemberInfo {
File = diFile, Line = 5, Name = "c", DebugType = i32Array_0_32, Index = 2
} };
#pragma warning restore
var fooType = new DebugStructType(module, "struct.foo", cu, "foo", diFile, 1, DebugInfoFlags.None, fooBody);
// 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 = targetData.AbiAlignmentOf(fooType);
bar.AddDebugInfo(module.DIBuilder.CreateGlobalVariableExpression(cu, "bar", string.Empty, diFile, 8, fooType.DIType, false, null));
var baz = module.AddGlobal(fooType, false, Linkage.Common, Constant.NullValueFor(fooType), "baz");
baz.Alignment = targetData.AbiAlignmentOf(fooType);
baz.AddDebugInfo(module.DIBuilder.CreateGlobalVariableExpression(cu, "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);
// create types for function args
var constFoo = module.DIBuilder.CreateQualifiedType(fooType.DIType, QualifiedTypeTag.Const);
var fooPtr = new DebugPointerType(fooType, module);
// 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.
Function doCopyFunc = DeclareDoCopyFunc(module, diFile, voidType);
Function copyFunc = DeclareCopyFunc(module, diFile, voidType, constFoo, fooPtr);
CreateCopyFunctionBody(module, targetData, copyFunc, diFile, fooType, fooPtr, constFoo);
CreateDoCopyFunctionBody(module, targetData, 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 diff 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);
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.
var pm = new ModulePassManager( )
.AddAlwaysInlinerPass( )
.AddAggressiveDCEPass( )
.AddArgumentPromotionPass( )
.AddBasicAliasAnalysisPass( )
.AddBitTrackingDCEPass( )
.AddCFGSimplificationPass( )
.AddConstantMergePass( )
.AddConstantPropagationPass( )
.AddFunctionInliningPass( )
.AddGlobalOptimizerPass( )
.AddInstructionCombiningPass( );
pm.Run(modForOpt);
}
// Module is good, so generate the output files
module.WriteToFile("test.bc");
File.WriteAllText("test.ll", module.WriteToString( ));
targetMachine.EmitToFile(module, "test.o", CodeGenFileType.ObjectFile);
targetMachine.EmitToFile(module, "test.s", CodeGenFileType.AssemblySource);
}
}
}
}
private static void CreateCopyFunctionBody(BitcodeModule module
, DataLayout layout
, Function copyFunc
, DIFile diFile
, ITypeRef foo
, DebugPointerType fooPtr
, DIType constFooType
)
{
var diBuilder = module.DIBuilder;
copyFunc.Parameters[0].Name = "src";
copyFunc.Parameters[1].Name = "pDst";
// create block for the function body, only need one for this simple sample
var blk = copyFunc.AppendBasicBlock("entry");
// create instruction builder to build the body
var instBuilder = new InstructionBuilder(blk);
// create debug info locals for the arguments
// NOTE: Debug parameter indices are 1 based!
var paramSrc = diBuilder.CreateArgument(copyFunc.DISubProgram, "src", diFile, 11, constFooType, false, 0, 1);
var paramDst = diBuilder.CreateArgument(copyFunc.DISubProgram, "pDst", diFile, 12, fooPtr.DIType, false, 0, 2);
uint ptrAlign = layout.CallFrameAlignmentOf(fooPtr);
// create Locals
// NOTE: There's no debug location attached to these instructions.
// The debug info will come from the declare intrinsic below.
var dstAddr = instBuilder.Alloca(fooPtr)
.RegisterName("pDst.addr")
.Alignment(ptrAlign);
bool param0ByVal = copyFunc.Attributes[FunctionAttributeIndex.Parameter0].Contains(AttributeKind.ByVal);
if (param0ByVal)
{
diBuilder.InsertDeclare(copyFunc.Parameters[0]
, paramSrc
, new DILocation(module.Context, 11, 43, copyFunc.DISubProgram)
, blk
);
}
instBuilder.Store(copyFunc.Parameters[1], dstAddr)
.Alignment(ptrAlign);
// insert declare pseudo instruction to attach debug info to the local declarations
diBuilder.InsertDeclare(dstAddr, paramDst, new DILocation(module.Context, 12, 38, copyFunc.DISubProgram), blk);
if (!param0ByVal)
{
// since the function's LLVM signature uses a pointer, which is copied locally
// inform the debugger to treat it as the value by dereferencing the pointer
diBuilder.InsertDeclare(copyFunc.Parameters[0]
, paramSrc
, diBuilder.CreateExpression(ExpressionOp.deref)
, new DILocation(module.Context, 11, 43, copyFunc.DISubProgram)
, blk
);
}
var loadedDst = instBuilder.Load(dstAddr)
.Alignment(ptrAlign)
.SetDebugLocation(15, 6, copyFunc.DISubProgram);
var dstPtr = instBuilder.BitCast(loadedDst, module.Context.Int8Type.CreatePointerType( ))
.SetDebugLocation(15, 13, copyFunc.DISubProgram);
var srcPtr = instBuilder.BitCast(copyFunc.Parameters[0], module.Context.Int8Type.CreatePointerType( ))
.SetDebugLocation(15, 13, copyFunc.DISubProgram);
uint pointerSize = layout.IntPtrType(module.Context).IntegerBitWidth;
instBuilder.MemCpy(module
, dstPtr
, srcPtr
, module.Context.CreateConstant(pointerSize, layout.ByteSizeOf(foo), false)
, ( int )layout.AbiAlignmentOf(foo)
, false
).SetDebugLocation(15, 13, copyFunc.DISubProgram);
instBuilder.Return( )
.SetDebugLocation(16, 1, copyFunc.DISubProgram);
}
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");
}
}