Rasagar/Library/PackageCache/com.unity.burst/Unity.Burst.CodeGen/ILPostProcessing.cs
2024-08-26 23:07:20 +03:00

940 lines
41 KiB
C#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Mono.Cecil;
using Mono.Cecil.Cil;
namespace zzzUnity.Burst.CodeGen
{
/// <summary>
/// Main class for post processing assemblies. The post processing is currently performing:
/// - Replace C# call from C# to Burst functions with attributes [BurstCompile] to a call to the compiled Burst function
/// In both editor and standalone scenarios. For DOTS Runtime, this is done differently at BclApp level by patching
/// DllImport.
/// - Replace calls to `SharedStatic.GetOrCreate` with `SharedStatic.GetOrCreateUnsafe`, and calculate the hashes during ILPP time
/// rather than in static constructors at runtime.
/// </summary>
internal class ILPostProcessing
{
private AssemblyDefinition _burstAssembly;
private MethodReference _burstCompilerIsEnabledMethodDefinition;
private MethodReference _burstCompilerCompileFunctionPointer;
private FieldReference _burstCompilerOptionsField;
private TypeReference _burstCompilerOptionsType;
private TypeReference _functionPointerType;
private MethodReference _functionPointerGetValue;
private MethodReference _burstDiscardAttributeConstructor;
private TypeSystem _typeSystem;
private TypeReference _systemDelegateType;
private TypeReference _systemASyncCallbackType;
private TypeReference _systemIASyncResultType;
private AssemblyDefinition _assemblyDefinition;
private bool _modified;
#if !UNITY_DOTSPLAYER
private bool _containsDirectCall;
#endif
private readonly StringBuilder _builder = new StringBuilder(1024);
private readonly List<Instruction> _instructionsToReplace = new List<Instruction>(4);
public const string PostfixManaged = "$BurstManaged";
private const string PostfixBurstDirectCall = "$BurstDirectCall";
private const string PostfixBurstDelegate = "$PostfixBurstDelegate";
private const string GetFunctionPointerName = "GetFunctionPointer";
private const string GetFunctionPointerDiscardName = "GetFunctionPointerDiscard";
private const string InvokeName = "Invoke";
public ILPostProcessing(AssemblyResolver loader, bool isForEditor, ErrorDiagnosticDelegate error, LogDelegate log = null, int logLevel = 0, bool skipInitializeOnLoad = false)
{
_skipInitializeOnLoad = skipInitializeOnLoad;
Loader = loader;
IsForEditor = isForEditor;
}
public bool _skipInitializeOnLoad;
public bool IsForEditor { get; private set; }
private AssemblyResolver Loader { get; }
public bool Run(AssemblyDefinition assemblyDefinition)
{
_assemblyDefinition = assemblyDefinition;
_typeSystem = assemblyDefinition.MainModule.TypeSystem;
_modified = false;
var types = assemblyDefinition.MainModule.GetTypes().ToArray();
foreach (var type in types)
{
ProcessType(type);
}
#if !UNITY_DOTSPLAYER
if (_containsDirectCall)
{
GenerateInitializeOnLoadMethod();
}
#endif
return _modified;
}
private void GenerateInitializeOnLoadMethod()
{
// This method is needed to ensure that BurstCompiler.Options is initialized on the main thread,
// before any direct call methods are called on a background thread.
// [UnityEngine.RuntimeInitializeOnLoadMethod(UnityEngine.RuntimeInitializeLoadType.AfterAssembliesLoaded)]
// [UnityEditor.InitializeOnLoadMethod] // When its an editor assembly
// private static void Initialize()
// {
// var _ = BurstCompiler.Options;
// }
const string initializeOnLoadClassName = "$BurstDirectCallInitializer";
var initializeOnLoadClass = _assemblyDefinition.MainModule.Types.FirstOrDefault(x => x.Name == initializeOnLoadClassName);
if (initializeOnLoadClass != null)
{
// If there's already a class with this name, remove it,
// This would mean that we're postprocessing an already-postprocessed assembly;
// I don't think that ever happens, but no sense in breaking if it does.
_assemblyDefinition.MainModule.Types.Remove(initializeOnLoadClass);
}
initializeOnLoadClass = new TypeDefinition(
"",
initializeOnLoadClassName,
TypeAttributes.NotPublic |
TypeAttributes.AutoLayout |
TypeAttributes.AnsiClass |
TypeAttributes.Abstract |
TypeAttributes.Sealed |
TypeAttributes.BeforeFieldInit)
{
BaseType = _typeSystem.Object
};
_assemblyDefinition.MainModule.Types.Add(initializeOnLoadClass);
var initializeOnLoadMethod = new MethodDefinition("Initialize", MethodAttributes.Private | MethodAttributes.HideBySig | MethodAttributes.Static, _typeSystem.Void)
{
ImplAttributes = MethodImplAttributes.IL | MethodImplAttributes.Managed,
DeclaringType = initializeOnLoadClass
};
initializeOnLoadMethod.Body.Variables.Add(new VariableDefinition(_burstCompilerOptionsType));
var processor = initializeOnLoadMethod.Body.GetILProcessor();
processor.Emit(OpCodes.Ldsfld, _burstCompilerOptionsField);
processor.Emit(OpCodes.Stloc_0);
processor.Emit(OpCodes.Ret);
initializeOnLoadClass.Methods.Add(FixDebugInformation(initializeOnLoadMethod));
var attribute = new CustomAttribute(_unityEngineInitializeOnLoadAttributeCtor);
attribute.ConstructorArguments.Add(new CustomAttributeArgument(_unityEngineRuntimeInitializeLoadType, _unityEngineRuntimeInitializeLoadAfterAssemblies.Constant));
initializeOnLoadMethod.CustomAttributes.Add(attribute);
if (IsForEditor && !_skipInitializeOnLoad)
{
// Need to ensure the editor tag for initialize on load is present, otherwise edit mode tests will not call Initialize
attribute = new CustomAttribute(_unityEditorInitilizeOnLoadAttributeCtor);
initializeOnLoadMethod.CustomAttributes.Add(attribute);
}
}
private static bool CanComputeCompileTimeHash(TypeReference typeRef)
{
if (typeRef.ContainsGenericParameter)
{
return false;
}
var assemblyNameReference = typeRef.Scope as AssemblyNameReference ?? typeRef.Module.Assembly?.Name;
if (assemblyNameReference == null)
{
return false;
}
switch (assemblyNameReference.Name)
{
case "netstandard":
case "mscorlib":
return false;
}
return true;
}
private void ProcessType(TypeDefinition type)
{
if (!type.HasGenericParameters && TryGetBurstCompileAttribute(type, out _))
{
// Make a copy because we are going to modify it
var methodCount = type.Methods.Count;
for (var j = 0; j < methodCount; j++)
{
var method = type.Methods[j];
if (!method.IsStatic || method.HasGenericParameters || !TryGetBurstCompileAttribute(method, out var methodBurstCompileAttribute)) continue;
bool isDirectCallDisabled = false;
bool foundProperty = false;
if (methodBurstCompileAttribute.HasProperties)
{
foreach (var property in methodBurstCompileAttribute.Properties)
{
if (property.Name == "DisableDirectCall")
{
isDirectCallDisabled = (bool)property.Argument.Value;
foundProperty = true;
break;
}
}
}
// If the method doesn't have a direct call specified, try the assembly level, do one last check for any assembly level [BurstCompile] instead.
if (foundProperty == false && TryGetBurstCompileAttribute(method.Module.Assembly, out var assemblyBurstCompileAttribute))
{
if (assemblyBurstCompileAttribute.HasProperties)
{
foreach (var property in assemblyBurstCompileAttribute.Properties)
{
if (property.Name == "DisableDirectCall")
{
isDirectCallDisabled = (bool)property.Argument.Value;
break;
}
}
}
}
foreach (var customAttribute in method.CustomAttributes)
{
if (customAttribute.AttributeType.FullName == "System.Runtime.InteropServices.UnmanagedCallersOnlyAttribute")
{
// Can't / shouldn't enable direct call for [UnmanagedCallersOnly] methods -
// these can't be called from managed code.
isDirectCallDisabled = true;
break;
}
}
#if !UNITY_DOTSPLAYER // Direct call is not Supported for dots runtime via this pre-processor, its handled elsewhere, this code assumes a Unity Editor based burst
if (!isDirectCallDisabled)
{
if (_burstAssembly == null)
{
var resolved = methodBurstCompileAttribute.Constructor.DeclaringType.Resolve();
InitializeBurstAssembly(resolved.Module.Assembly);
}
ProcessMethodForDirectCall(method);
_modified = true;
_containsDirectCall = true;
}
#endif
}
}
if (TypeHasSharedStaticInIt(type))
{
foreach (var method in type.Methods)
{
// Skip anything that isn't the static constructor.
if (method.Name != ".cctor")
{
continue;
}
try
{
#if DEBUG
if (_instructionsToReplace.Count != 0)
{
throw new InvalidOperationException("Instructions to replace wasn't cleared properly!");
}
#endif
foreach (var instruction in method.Body.Instructions)
{
// Skip anything that isn't a call.
if (instruction.OpCode != OpCodes.Call)
{
continue;
}
var calledMethod = (MethodReference)instruction.Operand;
if (calledMethod.Name != "GetOrCreate")
{
continue;
}
// Skip anything that isn't member of the `SharedStatic` class.
if (!TypeIsSharedStatic(calledMethod.DeclaringType))
{
continue;
}
// We only handle the `GetOrCreate` calls with a single parameter (the alignment).
if (calledMethod.Parameters.Count != 1)
{
continue;
}
// We only post-process the generic versions of `GetOrCreate`.
if (!(calledMethod is GenericInstanceMethod genericInstanceMethod))
{
continue;
}
var atLeastOneArgumentCanBeComputed = false;
foreach (var genericArgument in genericInstanceMethod.GenericArguments)
{
if (CanComputeCompileTimeHash(genericArgument))
{
atLeastOneArgumentCanBeComputed = true;
}
}
// We cannot post-process a shared static with all arguments being open generic.
// We cannot post-process a shared static where all of its types are in core libraries.
if (!atLeastOneArgumentCanBeComputed)
{
continue;
}
_instructionsToReplace.Add(instruction);
}
if (_instructionsToReplace.Count > 0)
{
_modified = true;
}
foreach (var instruction in _instructionsToReplace)
{
var calledMethod = (GenericInstanceMethod)instruction.Operand;
var hashCode64 = CalculateHashCode64(calledMethod.GenericArguments[0]);
long subHashCode64 = 0;
var useCalculatedHashCode = true;
var useCalculatedSubHashCode = true;
if (calledMethod.GenericArguments.Count == 2)
{
subHashCode64 = CalculateHashCode64(calledMethod.GenericArguments[1]);
useCalculatedHashCode = CanComputeCompileTimeHash(calledMethod.GenericArguments[0]);
useCalculatedSubHashCode = CanComputeCompileTimeHash(calledMethod.GenericArguments[1]);
}
#if DEBUG
if (!useCalculatedHashCode && !useCalculatedSubHashCode)
{
throw new InvalidOperationException("Cannot replace when both hashes are invalid!");
}
#endif
var methodToCall = "GetOrCreateUnsafe";
TypeReference genericArgument = null;
if (!useCalculatedHashCode)
{
methodToCall = "GetOrCreatePartiallyUnsafeWithSubHashCode";
genericArgument = calledMethod.GenericArguments[0];
}
else if (!useCalculatedSubHashCode)
{
methodToCall = "GetOrCreatePartiallyUnsafeWithHashCode";
genericArgument = calledMethod.GenericArguments[1];
}
var getOrCreateUnsafe = _assemblyDefinition.MainModule.ImportReference(
calledMethod.DeclaringType.Resolve().Methods.First(m => m.Name == methodToCall));
getOrCreateUnsafe.DeclaringType = calledMethod.DeclaringType;
if (genericArgument != null)
{
var genericInstanceMethod = new GenericInstanceMethod(getOrCreateUnsafe);
genericInstanceMethod.GenericArguments.Add(genericArgument);
getOrCreateUnsafe = genericInstanceMethod;
}
var processor = method.Body.GetILProcessor();
if (useCalculatedHashCode)
{
processor.InsertBefore(instruction, processor.Create(OpCodes.Ldc_I8, hashCode64));
}
if (useCalculatedSubHashCode)
{
processor.InsertBefore(instruction, processor.Create(OpCodes.Ldc_I8, subHashCode64));
}
processor.Replace(instruction, processor.Create(OpCodes.Call, getOrCreateUnsafe));
}
}
finally
{
_instructionsToReplace.Clear();
}
}
}
}
// WARNING: This **must** be kept in sync with the definition in BurstRuntime.cs!
private static long HashStringWithFNV1A64(string text)
{
// Using http://www.isthe.com/chongo/tech/comp/fnv/index.html#FNV-1a
// with basis and prime:
const ulong offsetBasis = 14695981039346656037;
const ulong prime = 1099511628211;
ulong result = offsetBasis;
foreach (var c in text)
{
result = prime * (result ^ (byte)(c & 255));
result = prime * (result ^ (byte)(c >> 8));
}
return (long)result;
}
private long CalculateHashCode64(TypeReference type)
{
try
{
#if DEBUG
if (_builder.Length != 0)
{
throw new InvalidOperationException("StringBuilder wasn't cleared properly!");
}
#endif
type.BuildAssemblyQualifiedName(_builder);
return HashStringWithFNV1A64(_builder.ToString());
}
finally
{
_builder.Clear();
}
}
private static bool TypeIsSharedStatic(TypeReference typeRef)
{
if (typeRef.Namespace != "Unity.Burst")
{
return false;
}
if (typeRef.Name != "SharedStatic`1")
{
return false;
}
return true;
}
private static bool TypeHasSharedStaticInIt(TypeDefinition typeDef)
{
foreach (var field in typeDef.Fields)
{
if (TypeIsSharedStatic(field.FieldType))
{
return true;
}
}
return false;
}
private TypeDefinition InjectDelegate(TypeDefinition declaringType, string originalName, MethodDefinition managed, string uniqueSuffix)
{
var injectedDelegateType = new TypeDefinition(declaringType.Namespace, $"{originalName}{uniqueSuffix}{PostfixBurstDelegate}",
TypeAttributes.NestedPublic |
TypeAttributes.AutoLayout |
TypeAttributes.AnsiClass |
TypeAttributes.Sealed
)
{
DeclaringType = declaringType,
BaseType = _systemDelegateType
};
declaringType.NestedTypes.Add(injectedDelegateType);
{
var constructor = new MethodDefinition(".ctor",
MethodAttributes.Public |
MethodAttributes.HideBySig |
MethodAttributes.SpecialName |
MethodAttributes.RTSpecialName,
_typeSystem.Void)
{
HasThis = true,
IsManaged = true,
IsRuntime = true,
DeclaringType = injectedDelegateType
};
constructor.Parameters.Add(new ParameterDefinition(_typeSystem.Object));
constructor.Parameters.Add(new ParameterDefinition(_typeSystem.IntPtr));
injectedDelegateType.Methods.Add(constructor);
}
{
var invoke = new MethodDefinition("Invoke",
MethodAttributes.Public |
MethodAttributes.HideBySig |
MethodAttributes.NewSlot |
MethodAttributes.Virtual,
managed.ReturnType)
{
HasThis = true,
IsManaged = true,
IsRuntime = true,
DeclaringType = injectedDelegateType
};
foreach (var parameter in managed.Parameters)
{
invoke.Parameters.Add(parameter);
}
injectedDelegateType.Methods.Add(invoke);
}
{
var beginInvoke = new MethodDefinition("BeginInvoke",
MethodAttributes.Public |
MethodAttributes.HideBySig |
MethodAttributes.NewSlot |
MethodAttributes.Virtual,
_systemIASyncResultType)
{
HasThis = true,
IsManaged = true,
IsRuntime = true,
DeclaringType = injectedDelegateType
};
foreach (var parameter in managed.Parameters)
{
beginInvoke.Parameters.Add(parameter);
}
beginInvoke.Parameters.Add(new ParameterDefinition(_systemASyncCallbackType));
beginInvoke.Parameters.Add(new ParameterDefinition(_typeSystem.Object));
injectedDelegateType.Methods.Add(beginInvoke);
}
{
var endInvoke = new MethodDefinition("EndInvoke",
MethodAttributes.Public |
MethodAttributes.HideBySig |
MethodAttributes.NewSlot |
MethodAttributes.Virtual,
managed.ReturnType)
{
HasThis = true,
IsManaged = true,
IsRuntime = true,
DeclaringType = injectedDelegateType
};
endInvoke.Parameters.Add(new ParameterDefinition(_systemIASyncResultType));
injectedDelegateType.Methods.Add(endInvoke);
}
return injectedDelegateType;
}
private MethodDefinition CreateGetFunctionPointerDiscardMethod(TypeDefinition cls, FieldDefinition pointerField, MethodDefinition targetMethod, TypeDefinition injectedDelegate)
{
var genericCompileFunctionPointer = new GenericInstanceMethod(_burstCompilerCompileFunctionPointer);
genericCompileFunctionPointer.GenericArguments.Add(injectedDelegate);
var genericFunctionPointerType = new GenericInstanceType(_functionPointerType);
genericFunctionPointerType.GenericArguments.Add(injectedDelegate);
var genericGetValue = new MethodReference(_functionPointerGetValue.Name, _functionPointerGetValue.ReturnType, genericFunctionPointerType);
foreach (var p in _functionPointerGetValue.Parameters)
{
genericGetValue.Parameters.Add(new ParameterDefinition(p.Name, p.Attributes, p.ParameterType));
}
genericGetValue.HasThis = _functionPointerGetValue.HasThis;
genericGetValue.MetadataToken = _functionPointerGetValue.MetadataToken;
/*var genericGetValue = new Mono.Cecil.GenericInstanceMethod(_functionPointerGetValue)
{
DeclaringType = genericFunctionPointerType
};*/
// Create GetFunctionPointerDiscard method:
//
// [BurstDiscard]
// public static void GetFunctionPointerDiscard(ref IntPtr ptr) {
// if (Pointer == null) {
// Pointer = BurstCompiler.CompileFunctionPointer<InjectedDelegate>(d);
// }
//
// ptr = Pointer
// }
var getFunctionPointerDiscardMethod = new MethodDefinition(GetFunctionPointerDiscardName, MethodAttributes.Private | MethodAttributes.HideBySig | MethodAttributes.Static, _typeSystem.Void)
{
ImplAttributes = MethodImplAttributes.IL | MethodImplAttributes.Managed,
DeclaringType = cls
};
getFunctionPointerDiscardMethod.Body.Variables.Add(new VariableDefinition(genericFunctionPointerType));
getFunctionPointerDiscardMethod.Parameters.Add(new ParameterDefinition(new ByReferenceType(_typeSystem.IntPtr)));
var processor = getFunctionPointerDiscardMethod.Body.GetILProcessor();
processor.Emit(OpCodes.Ldsfld, pointerField);
var branchPosition = processor.Body.Instructions[processor.Body.Instructions.Count - 1];
processor.Emit(OpCodes.Ldnull);
processor.Emit(OpCodes.Ldftn, targetMethod);
processor.Emit(OpCodes.Newobj, injectedDelegate.Methods.First(md => md.IsConstructor && md.Parameters.Count == 2));
processor.Emit(OpCodes.Call, genericCompileFunctionPointer);
processor.Emit(OpCodes.Stloc_0);
processor.Emit(OpCodes.Ldloca, 0);
processor.Emit(OpCodes.Call, genericGetValue);
processor.Emit(OpCodes.Stsfld, pointerField);
processor.Emit(OpCodes.Ldarg_0);
processor.InsertAfter(branchPosition, Instruction.Create(OpCodes.Brtrue, processor.Body.Instructions[processor.Body.Instructions.Count - 1]));
processor.Emit(OpCodes.Ldsfld, pointerField);
processor.Emit(OpCodes.Stind_I);
processor.Emit(OpCodes.Ret);
cls.Methods.Add(FixDebugInformation(getFunctionPointerDiscardMethod));
getFunctionPointerDiscardMethod.CustomAttributes.Add(new CustomAttribute(_burstDiscardAttributeConstructor));
return getFunctionPointerDiscardMethod;
}
private MethodDefinition CreateGetFunctionPointerMethod(TypeDefinition cls, MethodDefinition getFunctionPointerDiscardMethod)
{
// Create GetFunctionPointer method:
//
// public static IntPtr GetFunctionPointer() {
// var ptr;
// GetFunctionPointerDiscard(ref ptr);
// return ptr;
// }
var getFunctionPointerMethod = new MethodDefinition(GetFunctionPointerName, MethodAttributes.Private | MethodAttributes.HideBySig | MethodAttributes.Static, _typeSystem.IntPtr)
{
ImplAttributes = MethodImplAttributes.IL | MethodImplAttributes.Managed,
DeclaringType = cls
};
getFunctionPointerMethod.Body.Variables.Add(new VariableDefinition(_typeSystem.IntPtr));
getFunctionPointerMethod.Body.InitLocals = true;
var processor = getFunctionPointerMethod.Body.GetILProcessor();
processor.Emit(OpCodes.Ldc_I4_0);
processor.Emit(OpCodes.Conv_I);
processor.Emit(OpCodes.Stloc_0);
processor.Emit(OpCodes.Ldloca_S, (byte)0);
processor.Emit(OpCodes.Call, getFunctionPointerDiscardMethod);
processor.Emit(OpCodes.Ldloc_0);
processor.Emit(OpCodes.Ret);
cls.Methods.Add(FixDebugInformation(getFunctionPointerMethod));
return getFunctionPointerMethod;
}
private void ProcessMethodForDirectCall(MethodDefinition burstCompileMethod)
{
var declaringType = burstCompileMethod.DeclaringType;
var uniqueSuffix = $"_{burstCompileMethod.MetadataToken.RID:X8}";
var injectedDelegate = InjectDelegate(declaringType, burstCompileMethod.Name, burstCompileMethod, uniqueSuffix);
// Create a copy of the original method that will be the actual managed method
// The original method is patched at the end of this method to call
// the dispatcher that will go to the Burst implementation or the managed method (if in the editor and Burst is disabled)
var managedFallbackMethod = new MethodDefinition($"{burstCompileMethod.Name}{PostfixManaged}", burstCompileMethod.Attributes, burstCompileMethod.ReturnType)
{
DeclaringType = declaringType,
ImplAttributes = burstCompileMethod.ImplAttributes,
MetadataToken = burstCompileMethod.MetadataToken,
};
// Ensure the CustomAttributes are the same
managedFallbackMethod.CustomAttributes.Clear();
foreach (var attr in burstCompileMethod.CustomAttributes)
{
managedFallbackMethod.CustomAttributes.Add(attr);
}
declaringType.Methods.Add(managedFallbackMethod);
foreach (var parameter in burstCompileMethod.Parameters)
{
managedFallbackMethod.Parameters.Add(parameter);
}
// Copy the body from the original burst method to the managed fallback, we'll replace the burstCompileMethod body later.
managedFallbackMethod.Body.InitLocals = burstCompileMethod.Body.InitLocals;
managedFallbackMethod.Body.LocalVarToken = burstCompileMethod.Body.LocalVarToken;
managedFallbackMethod.Body.MaxStackSize = burstCompileMethod.Body.MaxStackSize;
foreach (var variable in burstCompileMethod.Body.Variables)
{
managedFallbackMethod.Body.Variables.Add(variable);
}
foreach (var instruction in burstCompileMethod.Body.Instructions)
{
managedFallbackMethod.Body.Instructions.Add(instruction);
}
foreach (var exceptionHandler in burstCompileMethod.Body.ExceptionHandlers)
{
managedFallbackMethod.Body.ExceptionHandlers.Add(exceptionHandler);
}
managedFallbackMethod.ImplAttributes &= MethodImplAttributes.NoInlining;
// 0x0100 is AggressiveInlining
managedFallbackMethod.ImplAttributes |= (MethodImplAttributes)0x0100;
// The method needs to be public because we query for it in the ILPP code.
managedFallbackMethod.Attributes &= ~MethodAttributes.Private;
managedFallbackMethod.Attributes |= MethodAttributes.Public;
// private static class (Name_RID.$Postfix)
var cls = new TypeDefinition(declaringType.Namespace, $"{burstCompileMethod.Name}{uniqueSuffix}{PostfixBurstDirectCall}",
TypeAttributes.NestedAssembly |
TypeAttributes.AutoLayout |
TypeAttributes.AnsiClass |
TypeAttributes.Abstract |
TypeAttributes.Sealed |
TypeAttributes.BeforeFieldInit
)
{
DeclaringType = declaringType,
BaseType = _typeSystem.Object
};
declaringType.NestedTypes.Add(cls);
// Create Field:
//
// private static IntPtr Pointer;
var pointerField = new FieldDefinition("Pointer", FieldAttributes.Static | FieldAttributes.Private, _typeSystem.IntPtr)
{
DeclaringType = cls
};
cls.Fields.Add(pointerField);
var getFunctionPointerDiscardMethod = CreateGetFunctionPointerDiscardMethod(
cls, pointerField,
// In the player the function pointer is looked up in a registry by name
// so we can't request a `$BurstManaged` function (because it was never compiled, only the toplevel one)
// But, it's safe *in the player* to request the toplevel function
IsForEditor ? managedFallbackMethod : burstCompileMethod,
injectedDelegate);
var getFunctionPointerMethod = CreateGetFunctionPointerMethod(cls, getFunctionPointerDiscardMethod);
// Create the Invoke method based on the original method (same signature)
//
// public static XXX Invoke(...args) {
// if (BurstCompiler.IsEnabled)
// {
// var funcPtr = GetFunctionPointer();
// if (funcPtr != null) return funcPtr(...args);
// }
// return OriginalMethod(...args);
// }
var invokeAttributes = managedFallbackMethod.Attributes;
invokeAttributes &= ~MethodAttributes.Private;
invokeAttributes |= MethodAttributes.Public;
var invoke = new MethodDefinition(InvokeName, invokeAttributes, burstCompileMethod.ReturnType)
{
ImplAttributes = MethodImplAttributes.IL | MethodImplAttributes.Managed,
DeclaringType = cls
};
var signature = new CallSite(burstCompileMethod.ReturnType)
{
CallingConvention = MethodCallingConvention.C
};
foreach (var parameter in burstCompileMethod.Parameters)
{
invoke.Parameters.Add(parameter);
signature.Parameters.Add(parameter);
}
invoke.Body.Variables.Add(new VariableDefinition(_typeSystem.IntPtr));
invoke.Body.InitLocals = true;
var processor = invoke.Body.GetILProcessor();
processor.Emit(OpCodes.Call, _burstCompilerIsEnabledMethodDefinition);
var branchPosition0 = processor.Body.Instructions[processor.Body.Instructions.Count - 1];
processor.Emit(OpCodes.Call, getFunctionPointerMethod);
processor.Emit(OpCodes.Stloc_0);
processor.Emit(OpCodes.Ldloc_0);
var branchPosition1 = processor.Body.Instructions[processor.Body.Instructions.Count - 1];
EmitArguments(processor, invoke);
processor.Emit(OpCodes.Ldloc_0);
processor.Emit(OpCodes.Calli, signature);
processor.Emit(OpCodes.Ret);
var previousRet = processor.Body.Instructions[processor.Body.Instructions.Count - 1];
EmitArguments(processor, invoke);
processor.Emit(OpCodes.Call, managedFallbackMethod);
processor.Emit(OpCodes.Ret);
// Insert the branch once we have emitted the instructions
processor.InsertAfter(branchPosition0, Instruction.Create(OpCodes.Brfalse, previousRet.Next));
processor.InsertAfter(branchPosition1, Instruction.Create(OpCodes.Brfalse, previousRet.Next));
cls.Methods.Add(FixDebugInformation(invoke));
// Final patching of the original method
// public static XXX OriginalMethod(...args) {
// Name_RID.$Postfix.Invoke(...args);
// ret;
// }
burstCompileMethod.Body = new MethodBody(burstCompileMethod);
processor = burstCompileMethod.Body.GetILProcessor();
EmitArguments(processor, burstCompileMethod);
processor.Emit(OpCodes.Call, invoke);
processor.Emit(OpCodes.Ret);
FixDebugInformation(burstCompileMethod);
}
private static MethodDefinition FixDebugInformation(MethodDefinition method)
{
method.DebugInformation.Scope = new ScopeDebugInformation(method.Body.Instructions.First(), method.Body.Instructions.Last());
return method;
}
private AssemblyDefinition GetAsmDefinitionFromFile(AssemblyResolver loader, string assemblyName)
{
if (loader.TryResolve(AssemblyNameReference.Parse(assemblyName), out var result))
{
return result;
}
return null;
}
private MethodReference _unityEngineInitializeOnLoadAttributeCtor;
private TypeReference _unityEngineRuntimeInitializeLoadType;
private FieldDefinition _unityEngineRuntimeInitializeLoadAfterAssemblies;
private MethodReference _unityEditorInitilizeOnLoadAttributeCtor;
private void InitializeBurstAssembly(AssemblyDefinition burstAssembly)
{
_burstAssembly = burstAssembly;
var burstCompilerTypeDefinition = burstAssembly.MainModule.GetType("Unity.Burst", "BurstCompiler");
_burstCompilerIsEnabledMethodDefinition = _assemblyDefinition.MainModule.ImportReference(burstCompilerTypeDefinition.Methods.FirstOrDefault(x => x.Name == "get_IsEnabled"));
_burstCompilerCompileFunctionPointer = _assemblyDefinition.MainModule.ImportReference(burstCompilerTypeDefinition.Methods.FirstOrDefault(x => x.Name == "CompileFunctionPointer"));
_burstCompilerOptionsField = _assemblyDefinition.MainModule.ImportReference(burstCompilerTypeDefinition.Fields.FirstOrDefault(x => x.Name == "Options"));
_burstCompilerOptionsType = _assemblyDefinition.MainModule.ImportReference(burstAssembly.MainModule.GetType("Unity.Burst", "BurstCompilerOptions"));
var functionPointerTypeDefinition = burstAssembly.MainModule.GetType("Unity.Burst", "FunctionPointer`1");
_functionPointerType = _assemblyDefinition.MainModule.ImportReference(functionPointerTypeDefinition);
_functionPointerGetValue = _assemblyDefinition.MainModule.ImportReference(functionPointerTypeDefinition.Methods.FirstOrDefault(x => x.Name == "get_Value"));
var corLibrary = Loader.Resolve((AssemblyNameReference)_typeSystem.CoreLibrary);
_systemDelegateType = _assemblyDefinition.MainModule.ImportReference(corLibrary.MainModule.GetType("System.MulticastDelegate"));
_systemASyncCallbackType = _assemblyDefinition.MainModule.ImportReference(corLibrary.MainModule.GetType("System.AsyncCallback"));
_systemIASyncResultType = _assemblyDefinition.MainModule.ImportReference(corLibrary.MainModule.GetType("System.IAsyncResult"));
var asmDef = GetAsmDefinitionFromFile(Loader, "UnityEngine.CoreModule");
var runtimeInitializeOnLoadMethodAttribute = asmDef.MainModule.GetType("UnityEngine", "RuntimeInitializeOnLoadMethodAttribute");
var runtimeInitializeLoadType = asmDef.MainModule.GetType("UnityEngine", "RuntimeInitializeLoadType");
var burstDiscardType = asmDef.MainModule.GetType("Unity.Burst", "BurstDiscardAttribute");
_burstDiscardAttributeConstructor = _assemblyDefinition.MainModule.ImportReference(burstDiscardType.Methods.First(method => method.Name == ".ctor"));
_unityEngineInitializeOnLoadAttributeCtor = _assemblyDefinition.MainModule.ImportReference(runtimeInitializeOnLoadMethodAttribute.Methods.FirstOrDefault(x => x.Name == ".ctor" && x.HasParameters));
_unityEngineRuntimeInitializeLoadType = _assemblyDefinition.MainModule.ImportReference(runtimeInitializeLoadType);
_unityEngineRuntimeInitializeLoadAfterAssemblies = runtimeInitializeLoadType.Fields.FirstOrDefault(x => x.Name == "AfterAssembliesLoaded");
if (IsForEditor && !_skipInitializeOnLoad)
{
asmDef = GetAsmDefinitionFromFile(Loader, "UnityEditor.CoreModule");
if (asmDef == null)
asmDef = GetAsmDefinitionFromFile(Loader, "UnityEditor");
var initializeOnLoadMethodAttribute = asmDef.MainModule.GetType("UnityEditor", "InitializeOnLoadMethodAttribute");
_unityEditorInitilizeOnLoadAttributeCtor = _assemblyDefinition.MainModule.ImportReference(initializeOnLoadMethodAttribute.Methods.FirstOrDefault(x => x.Name == ".ctor" && !x.HasParameters));
}
}
private static void EmitArguments(ILProcessor processor, MethodDefinition method)
{
for (var i = 0; i < method.Parameters.Count; i++)
{
switch (i)
{
case 0:
processor.Emit(OpCodes.Ldarg_0);
break;
case 1:
processor.Emit(OpCodes.Ldarg_1);
break;
case 2:
processor.Emit(OpCodes.Ldarg_2);
break;
case 3:
processor.Emit(OpCodes.Ldarg_3);
break;
default:
if (i <= 255)
{
processor.Emit(OpCodes.Ldarg_S, (byte)i);
}
else
{
processor.Emit(OpCodes.Ldarg, i);
}
break;
}
}
}
private static bool TryGetBurstCompileAttribute(ICustomAttributeProvider provider, out CustomAttribute customAttribute)
{
if (provider.HasCustomAttributes)
{
foreach (var customAttr in provider.CustomAttributes)
{
if (customAttr.Constructor.DeclaringType.Name == "BurstCompileAttribute")
{
customAttribute = customAttr;
return true;
}
}
}
customAttribute = null;
return false;
}
}
}