private static MethodSpec GetVirtualMethod(TypeSpec impl_ts, MethodSpec decl_ms,
target.Target t, bool allow_non_virtual = false)
{
/* Iterate through methods looking for virtual ones */
var first_mdef = impl_ts.m.GetIntEntry(MetadataStream.tid_TypeDef,
impl_ts.tdrow, 5);
var last_mdef = impl_ts.m.GetLastMethodDef(impl_ts.tdrow);
for (uint mdef_row = first_mdef; mdef_row < last_mdef; mdef_row++)
{
var flags = impl_ts.m.GetIntEntry(MetadataStream.tid_MethodDef,
(int)mdef_row, 2);
if (allow_non_virtual || (flags & 0x40) == 0x40)
{
MethodSpec impl_ms;
impl_ts.m.GetMethodDefRow(MetadataStream.tid_MethodDef,
(int)mdef_row, out impl_ms, impl_ts.gtparams, null);
impl_ms.type = impl_ts;
if ((flags & 0x400) != 0x400)
{
// Not marked abstract
if (MetadataStream.CompareString(impl_ms.m,
impl_ms.m.GetIntEntry(MetadataStream.tid_MethodDef, (int)mdef_row, 3),
decl_ms.m,
decl_ms.m.GetIntEntry(MetadataStream.tid_MethodDef, (int)decl_ms.mdrow, 3)))
{
if (MetadataStream.CompareSignature(impl_ms.m, impl_ms.msig,
impl_ts.gtparams, null,
decl_ms.m, decl_ms.msig, impl_ts.gtparams, null))
{
// this is the correct one
return(impl_ms);
}
if (MetadataStream.CompareSignature(impl_ms.m, impl_ms.msig,
impl_ts.gtparams, null,
decl_ms.m, decl_ms.msig, decl_ms.gtparams, null))
{
// this is the correct one
return(impl_ms);
}
}
}
}
}
// if not found, look to base classes
var bc = impl_ts.GetExtends();
if (bc != null)
{
return(GetVirtualMethod(bc, decl_ms, t, allow_non_virtual));
}
else
{
return(null);
}
}
private static int GetVTableIndex(MethodSpec ms, List <VTableItem> list)
{
for (int idx = 0; idx < list.Count; idx++)
{
var i = list[idx];
if (MetadataStream.CompareString(ms.m, ms.m.GetIntEntry(MetadataStream.tid_MethodDef, ms.mdrow, 3),
i.unimpl_meth.m, i.unimpl_meth.m.GetIntEntry(MetadataStream.tid_MethodDef, i.unimpl_meth.mdrow, 3)))
{
if (MetadataStream.CompareSignature(ms, i.unimpl_meth))
{
return(idx);
}
}
}
return(-1);
}
public static int GetVTableOffset(metadata.TypeSpec ts,
metadata.MethodSpec ms, Target t)
{
var vtbl = GetVirtualMethodDeclarations(ts);
var search_meth_name = ms.m.GetIntEntry(MetadataStream.tid_MethodDef,
ms.mdrow, 3);
// find the requested method, match on name, signature and declaring type
for (int i = 0; i < vtbl.Count; i++)
{
var test = vtbl[i];
var mdecl = test.unimpl_meth;
if (mdecl.type.Equals(ts))
{
// Check on name
var mname = mdecl.m.GetIntEntry(MetadataStream.tid_MethodDef,
mdecl.mdrow, 3);
if (MetadataStream.CompareString(mdecl.m, mname,
ms.m, search_meth_name))
{
// Check on signature
if (MetadataStream.CompareSignature(mdecl.m, mdecl.msig,
mdecl.gtparams, mdecl.gmparams,
ms.m, ms.msig, ms.gtparams, ms.gmparams))
{
if (ts.IsInterface == false)
{
i += (6 + t.ExtraVTableFieldsPointerLength);
}
return(i);
}
}
}
}
throw new Exception("Requested virtual method slot not found");
}
public static void ImplementVirtualMethods(TypeSpec ts, List <VTableItem> list)
{
// We implement those methods in the most derived class first and work back
foreach (var i in list)
{
// skip if already done
if (i.impl_meth != null)
{
continue;
}
// if we've gone back far enough to the max_implementor class
// we can start looking for implementations from here
if (i.max_implementor != null && i.max_implementor.Equals(ts))
{
i.max_implementor = null;
}
// if we haven't, skip this method for this class (it will be
// implemented in a base class)
if (i.max_implementor != null)
{
continue;
}
// Now, search for a matching method in this particular class
/* Iterate through methods looking for virtual ones */
var first_mdef = ts.m.GetIntEntry(MetadataStream.tid_TypeDef,
ts.tdrow, 5);
var last_mdef = ts.m.GetLastMethodDef(ts.tdrow);
var search_meth_name = i.unimpl_meth.m.GetIntEntry(MetadataStream.tid_MethodDef,
i.unimpl_meth.mdrow, 3);
for (uint mdef_row = first_mdef; mdef_row < last_mdef; mdef_row++)
{
var flags = ts.m.GetIntEntry(MetadataStream.tid_MethodDef,
(int)mdef_row, 2);
if ((flags & 0x40) == 0x40)
{
// its a virtual method
MethodSpec impl_ms;
ts.m.GetMethodDefRow(MetadataStream.tid_MethodDef,
(int)mdef_row, out impl_ms, ts.gtparams, null);
impl_ms.type = ts;
// compare on name
if (MetadataStream.CompareString(i.unimpl_meth.m, search_meth_name,
ts.m, ts.m.GetIntEntry(MetadataStream.tid_MethodDef, (int)mdef_row, 3)))
{
// and on signature
if (MetadataStream.CompareSignature(i.unimpl_meth, impl_ms))
{
// If its marked abstract, we dont implement it
if ((flags & 0x400) == 0x400)
{
i.impl_meth = null;
}
else
{
// we have found a valid implementing method
i.impl_meth = impl_ms;
}
}
}
}
}
}
// now implement on base classes
var extends = ts.GetExtends();
if (extends != null)
{
ImplementVirtualMethods(extends, list);
}
}