private static bool System_arraycopy(EmitIntrinsicContext eic)
{
// if the array arguments on the stack are of a known array type, we can redirect to an optimized version of arraycopy.
// Note that we also have to handle VMSystem.arraycopy, because on GNU Classpath StringBuffer directly calls
// this method to avoid prematurely initialising System.
TypeWrapper dst_type = eic.GetStackTypeWrapper(0, 2);
TypeWrapper src_type = eic.GetStackTypeWrapper(0, 4);
if (!dst_type.IsUnloadable && dst_type.IsArray && dst_type == src_type)
{
switch (dst_type.Name[1])
{
case 'J':
case 'D':
eic.Emitter.Emit(OpCodes.Call, ByteCodeHelperMethods.arraycopy_primitive_8);
break;
case 'I':
case 'F':
eic.Emitter.Emit(OpCodes.Call, ByteCodeHelperMethods.arraycopy_primitive_4);
break;
case 'S':
case 'C':
eic.Emitter.Emit(OpCodes.Call, ByteCodeHelperMethods.arraycopy_primitive_2);
break;
case 'B':
case 'Z':
eic.Emitter.Emit(OpCodes.Call, ByteCodeHelperMethods.arraycopy_primitive_1);
break;
default:
// TODO once the verifier tracks actual types (i.e. it knows that
// a particular reference is the result of a "new" opcode) we can
// use the fast version if the exact destination type is known
// (in that case the "dst_type == src_type" above should
// be changed to "src_type.IsAssignableTo(dst_type)".
TypeWrapper elemtw = dst_type.ElementTypeWrapper;
// note that IsFinal returns true for array types, so we have to be careful!
if (!elemtw.IsArray && elemtw.IsFinal)
{
eic.Emitter.Emit(OpCodes.Call, ByteCodeHelperMethods.arraycopy_fast);
}
else
{
eic.Emitter.Emit(OpCodes.Call, ByteCodeHelperMethods.arraycopy);
}
break;
}
return(true);
}
else
{
return(false);
}
}
private static bool Object_getClass(EmitIntrinsicContext eic)
{
// this is the null-check idiom that javac uses (both in its own source and in the code it generates)
if (eic.MatchRange(0, 2) &&
eic.Match(1, NormalizedByteCode.__pop))
{
eic.Emitter.Emit(OpCodes.Dup);
eic.Emitter.EmitNullCheck();
return(true);
}
// this optimizes obj1.getClass() ==/!= obj2.getClass()
else if (eic.MatchRange(0, 4) &&
eic.Match(1, NormalizedByteCode.__aload) &&
eic.Match(2, NormalizedByteCode.__invokevirtual) &&
(eic.Match(3, NormalizedByteCode.__if_acmpeq) || eic.Match(3, NormalizedByteCode.__if_acmpne)) &&
(IsSafeForGetClassOptimization(eic.GetStackTypeWrapper(0, 0)) || IsSafeForGetClassOptimization(eic.GetStackTypeWrapper(2, 0))))
{
ClassFile.ConstantPoolItemMI cpi = eic.GetMethodref(2);
if (cpi.Class == "java.lang.Object" && cpi.Name == "getClass" && cpi.Signature == "()Ljava.lang.Class;")
{
// we can't patch the current opcode, so we have to emit the first call to GetTypeHandle here
eic.Emitter.Emit(OpCodes.Callvirt, Compiler.getTypeMethod);
eic.PatchOpCode(2, NormalizedByteCode.__intrinsic_gettype);
return(true);
}
}
return(false);
}
private static bool Unsafe_getObjectVolatile(EmitIntrinsicContext eic)
{
// the check here must be kept in sync with the hack in MethodAnalyzer.AnalyzeTypeFlow()
TypeWrapper tw = eic.GetStackTypeWrapper(0, 1);
if (IsSupportedArrayTypeForUnsafeOperation(tw))
{
CodeEmitterLocal index = eic.Emitter.AllocTempLocal(Types.Int32);
CodeEmitterLocal obj = eic.Emitter.AllocTempLocal(tw.TypeAsLocalOrStackType);
eic.Emitter.Emit(OpCodes.Conv_Ovf_I4);
eic.Emitter.Emit(OpCodes.Stloc, index);
eic.Emitter.Emit(OpCodes.Stloc, obj);
EmitConsumeUnsafe(eic);
eic.Emitter.Emit(OpCodes.Ldloc, obj);
eic.Emitter.Emit(OpCodes.Ldloc, index);
eic.Emitter.ReleaseTempLocal(obj);
eic.Emitter.ReleaseTempLocal(index);
eic.Emitter.Emit(OpCodes.Ldelema, tw.TypeAsLocalOrStackType.GetElementType());
eic.Emitter.Emit(OpCodes.Volatile);
eic.Emitter.Emit(OpCodes.Ldind_Ref);
// remove the redundant checkcast that usually follows
if (eic.Code[eic.OpcodeIndex + 1].NormalizedOpCode == NormalizedByteCode.__checkcast &&
tw.ElementTypeWrapper.IsAssignableTo(eic.ClassFile.GetConstantPoolClassType(eic.Code[eic.OpcodeIndex + 1].Arg1)))
{
eic.PatchOpCode(1, NormalizedByteCode.__nop);
}
eic.NonLeaf = false;
return(true);
}
return(false);
}
private static bool Object_getClass(EmitIntrinsicContext eic)
{
// this is the null-check idiom that javac uses (both in its own source and in the code it generates)
if (eic.MatchRange(0, 2) &&
eic.Match(1, NormalizedByteCode.__pop))
{
eic.Emitter.Emit(OpCodes.Dup);
eic.Emitter.EmitNullCheck();
return(true);
}
// this optimizes obj1.getClass() ==/!= obj2.getClass()
else if (eic.MatchRange(0, 4) &&
eic.Match(1, NormalizedByteCode.__aload) &&
eic.Match(2, NormalizedByteCode.__invokevirtual) &&
(eic.Match(3, NormalizedByteCode.__if_acmpeq) || eic.Match(3, NormalizedByteCode.__if_acmpne)) &&
(IsSafeForGetClassOptimization(eic.GetStackTypeWrapper(0, 0)) || IsSafeForGetClassOptimization(eic.GetStackTypeWrapper(2, 0))))
{
ClassFile.ConstantPoolItemMI cpi = eic.GetMethodref(2);
if (cpi.Class == "java.lang.Object" && cpi.Name == "getClass" && cpi.Signature == "()Ljava.lang.Class;")
{
// we can't patch the current opcode, so we have to emit the first call to GetTypeHandle here
eic.Emitter.Emit(OpCodes.Callvirt, Compiler.getTypeMethod);
eic.PatchOpCode(2, NormalizedByteCode.__intrinsic_gettype);
return(true);
}
}
// this optimizes obj.getClass() == Xxx.class
else if (eic.MatchRange(0, 3) &&
eic.Match(1, NormalizedByteCode.__ldc) && eic.GetConstantType(1) == ClassFile.ConstantType.Class &&
(eic.Match(2, NormalizedByteCode.__if_acmpeq) || eic.Match(2, NormalizedByteCode.__if_acmpne)))
{
TypeWrapper tw = eic.GetClassLiteral(1);
if (tw.IsGhost || tw.IsGhostArray || tw.IsUnloadable || (tw.IsRemapped && tw.IsFinal && tw is DotNetTypeWrapper))
{
return(false);
}
eic.Emitter.Emit(OpCodes.Callvirt, Compiler.getTypeMethod);
eic.Emitter.Emit(OpCodes.Ldtoken, (tw.IsRemapped && tw.IsFinal) ? tw.TypeAsTBD : tw.TypeAsBaseType);
eic.Emitter.Emit(OpCodes.Call, Compiler.getTypeFromHandleMethod);
eic.PatchOpCode(1, NormalizedByteCode.__nop);
return(true);
}
return(false);
}
private static bool Unsafe_compareAndSwapObject(EmitIntrinsicContext eic)
{
TypeWrapper tw = eic.GetStackTypeWrapper(0, 3);
if (IsSupportedArrayTypeForUnsafeOperation(tw) &&
eic.GetStackTypeWrapper(0, 0).IsAssignableTo(tw.ElementTypeWrapper) &&
eic.GetStackTypeWrapper(0, 1).IsAssignableTo(tw.ElementTypeWrapper))
{
Type type = tw.TypeAsLocalOrStackType.GetElementType();
CodeEmitterLocal update = eic.Emitter.AllocTempLocal(type);
CodeEmitterLocal expect = eic.Emitter.AllocTempLocal(type);
CodeEmitterLocal index = eic.Emitter.AllocTempLocal(Types.Int32);
CodeEmitterLocal obj = eic.Emitter.AllocTempLocal(tw.TypeAsLocalOrStackType);
eic.Emitter.Emit(OpCodes.Stloc, update);
eic.Emitter.Emit(OpCodes.Stloc, expect);
eic.Emitter.Emit(OpCodes.Conv_Ovf_I4);
eic.Emitter.Emit(OpCodes.Stloc, index);
eic.Emitter.Emit(OpCodes.Stloc, obj);
EmitConsumeUnsafe(eic);
eic.Emitter.Emit(OpCodes.Ldloc, obj);
eic.Emitter.Emit(OpCodes.Ldloc, index);
eic.Emitter.Emit(OpCodes.Ldelema, type);
eic.Emitter.Emit(OpCodes.Ldloc, update);
eic.Emitter.Emit(OpCodes.Ldloc, expect);
eic.Emitter.Emit(OpCodes.Call, AtomicReferenceFieldUpdaterEmitter.MakeCompareExchange(type));
eic.Emitter.Emit(OpCodes.Ldloc, expect);
eic.Emitter.Emit(OpCodes.Ceq);
eic.Emitter.ReleaseTempLocal(obj);
eic.Emitter.ReleaseTempLocal(index);
eic.Emitter.ReleaseTempLocal(expect);
eic.Emitter.ReleaseTempLocal(update);
eic.NonLeaf = false;
return(true);
}
if ((eic.Flags[eic.OpcodeIndex] & InstructionFlags.BranchTarget) != 0 ||
(eic.Flags[eic.OpcodeIndex - 1] & InstructionFlags.BranchTarget) != 0 ||
(eic.Flags[eic.OpcodeIndex - 2] & InstructionFlags.BranchTarget) != 0)
{
return(false);
}
if ((eic.Match(-1, NormalizedByteCode.__aload) || eic.Match(-1, NormalizedByteCode.__aconst_null)) &&
(eic.Match(-2, NormalizedByteCode.__aload) || eic.Match(-2, NormalizedByteCode.__aconst_null)) &&
eic.Match(-3, NormalizedByteCode.__getstatic))
{
FieldWrapper fw = GetUnsafeField(eic, eic.GetFieldref(-3));
if (fw != null &&
fw.IsAccessibleFrom(fw.DeclaringType, eic.Caller.DeclaringType, fw.DeclaringType) &&
eic.GetStackTypeWrapper(0, 0).IsAssignableTo(fw.FieldTypeWrapper) &&
eic.GetStackTypeWrapper(0, 1).IsAssignableTo(fw.FieldTypeWrapper) &&
(fw.IsStatic || fw.DeclaringType == eic.GetStackTypeWrapper(0, 3)))
{
Type type = fw.FieldTypeWrapper.TypeAsLocalOrStackType;
CodeEmitterLocal update = eic.Emitter.AllocTempLocal(type);
CodeEmitterLocal expect = eic.Emitter.AllocTempLocal(type);
eic.Emitter.Emit(OpCodes.Stloc, update);
eic.Emitter.Emit(OpCodes.Stloc, expect);
eic.Emitter.Emit(OpCodes.Pop); // discard index
if (fw.IsStatic)
{
eic.Emitter.Emit(OpCodes.Pop); // discard obj
EmitConsumeUnsafe(eic);
eic.Emitter.Emit(OpCodes.Ldsflda, fw.GetField());
}
else
{
CodeEmitterLocal obj = eic.Emitter.AllocTempLocal(eic.Caller.DeclaringType.TypeAsLocalOrStackType);
eic.Emitter.Emit(OpCodes.Stloc, obj);
EmitConsumeUnsafe(eic);
eic.Emitter.Emit(OpCodes.Ldloc, obj);
eic.Emitter.ReleaseTempLocal(obj);
eic.Emitter.Emit(OpCodes.Ldflda, fw.GetField());
}
eic.Emitter.Emit(OpCodes.Ldloc, update);
eic.Emitter.Emit(OpCodes.Ldloc, expect);
eic.Emitter.Emit(OpCodes.Call, AtomicReferenceFieldUpdaterEmitter.MakeCompareExchange(type));
eic.Emitter.Emit(OpCodes.Ldloc, expect);
eic.Emitter.Emit(OpCodes.Ceq);
eic.Emitter.ReleaseTempLocal(expect);
eic.Emitter.ReleaseTempLocal(update);
eic.NonLeaf = false;
return(true);
}
}
return(false);
}
private static bool Unsafe_putObjectImpl(EmitIntrinsicContext eic, bool membarrier)
{
TypeWrapper tw = eic.GetStackTypeWrapper(0, 2);
if (IsSupportedArrayTypeForUnsafeOperation(tw) &&
eic.GetStackTypeWrapper(0, 0).IsAssignableTo(tw.ElementTypeWrapper))
{
CodeEmitterLocal value = eic.Emitter.AllocTempLocal(tw.ElementTypeWrapper.TypeAsLocalOrStackType);
CodeEmitterLocal index = eic.Emitter.AllocTempLocal(Types.Int32);
CodeEmitterLocal array = eic.Emitter.AllocTempLocal(tw.TypeAsLocalOrStackType);
eic.Emitter.Emit(OpCodes.Stloc, value);
eic.Emitter.Emit(OpCodes.Conv_Ovf_I4);
eic.Emitter.Emit(OpCodes.Stloc, index);
eic.Emitter.Emit(OpCodes.Stloc, array);
EmitConsumeUnsafe(eic);
eic.Emitter.Emit(OpCodes.Ldloc, array);
eic.Emitter.Emit(OpCodes.Ldloc, index);
eic.Emitter.Emit(OpCodes.Ldloc, value);
eic.Emitter.ReleaseTempLocal(array);
eic.Emitter.ReleaseTempLocal(index);
eic.Emitter.ReleaseTempLocal(value);
eic.Emitter.Emit(OpCodes.Stelem_Ref);
if (membarrier)
{
eic.Emitter.EmitMemoryBarrier();
}
eic.NonLeaf = false;
return(true);
}
if ((eic.Flags[eic.OpcodeIndex] & InstructionFlags.BranchTarget) != 0 ||
(eic.Flags[eic.OpcodeIndex - 1] & InstructionFlags.BranchTarget) != 0)
{
return(false);
}
if ((eic.Match(-1, NormalizedByteCode.__aload) || eic.Match(-1, NormalizedByteCode.__aconst_null)) &&
eic.Match(-2, NormalizedByteCode.__getstatic))
{
FieldWrapper fw = GetUnsafeField(eic, eic.GetFieldref(-2));
if (fw != null &&
(!fw.IsFinal || (!fw.IsStatic && eic.Caller.Name == "<init>") || (fw.IsStatic && eic.Caller.Name == "<clinit>")) &&
fw.IsAccessibleFrom(fw.DeclaringType, eic.Caller.DeclaringType, fw.DeclaringType) &&
eic.GetStackTypeWrapper(0, 0).IsAssignableTo(fw.FieldTypeWrapper) &&
(fw.IsStatic || fw.DeclaringType == eic.GetStackTypeWrapper(0, 2)))
{
CodeEmitterLocal value = eic.Emitter.AllocTempLocal(fw.FieldTypeWrapper.TypeAsLocalOrStackType);
eic.Emitter.Emit(OpCodes.Stloc, value);
eic.Emitter.Emit(OpCodes.Pop); // discard offset field
if (fw.IsStatic)
{
eic.Emitter.Emit(OpCodes.Pop); // discard object
EmitConsumeUnsafe(eic);
}
else
{
CodeEmitterLocal obj = eic.Emitter.AllocTempLocal(fw.DeclaringType.TypeAsLocalOrStackType);
eic.Emitter.Emit(OpCodes.Stloc, obj);
EmitConsumeUnsafe(eic);
eic.Emitter.Emit(OpCodes.Ldloc, obj);
eic.Emitter.ReleaseTempLocal(obj);
}
eic.Emitter.Emit(OpCodes.Ldloc, value);
eic.Emitter.ReleaseTempLocal(value);
// note that we assume the CLR memory model where all writes are ordered,
// so we don't need a volatile store or a memory barrier and putOrderedObject
// is typically used with a volatile field, so to avoid the memory barrier,
// we don't use FieldWrapper.EmitSet(), but emit the store directly
eic.Emitter.Emit(fw.IsStatic ? OpCodes.Stsfld : OpCodes.Stfld, fw.GetField());
if (membarrier)
{
eic.Emitter.EmitMemoryBarrier();
}
eic.NonLeaf = false;
return(true);
}
}
return(false);
}
