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switch to using CSTRMarshaller instead of AnsiBSTR #55032

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Merged
mangod9 merged 9 commits into from
Jul 13, 2021
Merged

switch to using CSTRMarshaller instead of AnsiBSTR #55032

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42ff51a
switch to using CSTRMarshaller instead of AnsiBSTR
mangod9 Jul 1, 2021
821aece
cleanup
mangod9 Jul 1, 2021
39f17b8
Add CleanupManaged back
mangod9 Jul 2, 2021
5d24e5a
CR feedback
mangod9 Jul 2, 2021
f4f44c8
update MAX_LOCAL_BUFFER_LENGTH
mangod9 Jul 6, 2021
8575306
generate stubs for all methods if corelib is within the bubble.
mangod9 Jul 8, 2021
a3f5ac2
Revert "generate stubs for all methods if corelib is within the bubble."
mangod9 Jul 8, 2021
185ccc0
CR feedback
mangod9 Jul 12, 2021
56f8cbe
use wellknowntype
mangod9 Jul 12, 2021
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90 changes: 87 additions & 3 deletions src/coreclr/tools/Common/TypeSystem/Interop/IL/Marshaller.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -1581,6 +1581,10 @@ protected override void EmitCleanupManaged(ILCodeStream codeStream)

class AnsiStringMarshaller : Marshaller
{
const int MAX_LOCAL_BUFFER_LENGTH = 260 + 1; // MAX_PATH + 1

private ILLocalVariable _localBuffer = default;

internal override bool CleanupRequired
{
get
Expand All @@ -1605,12 +1609,75 @@ protected override void TransformManagedToNative(ILCodeStream codeStream)

#if READYTORUN
var stringToAnsi =
Context.SystemModule.GetKnownType("System.StubHelpers", "AnsiBSTRMarshaler")
Context.SystemModule.GetKnownType("System.StubHelpers", "CSTRMarshaler")
.GetKnownMethod("ConvertToNative", null);

bool bPassByValueInOnly = In && !Out && !IsManagedByRef;

if (bPassByValueInOnly)
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@mangod9 mangod9 Jul 1, 2021

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is there a reason why this logic cant move to System.StubHelpers.CSTRMarshaler ?

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@jkotas jkotas Jul 1, 2021

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Yes, it would be nice to have majority of the logic in C#, and minimize amount of the hand-emitted IL.

{
var bufSize = emitter.NewLocal(Context.GetWellKnownType(WellKnownType.Int32));
_localBuffer = emitter.NewLocal(Context.GetWellKnownType(WellKnownType.IntPtr));

// LocalBuffer = 0
codeStream.Emit(ILOpcode.ldnull);
codeStream.EmitStLoc(_localBuffer);

var noOptimize = emitter.NewCodeLabel();

// if == NULL, goto NoOptimize
LoadManagedValue(codeStream);
codeStream.Emit(ILOpcode.brfalse, noOptimize);

// String.Length + 2
LoadManagedValue(codeStream);
var stringLen =
Context.SystemModule.GetKnownType("System", "String")
.GetKnownMethod("get_Length", null);
codeStream.Emit(ILOpcode.call, emitter.NewToken(stringLen));
codeStream.EmitLdc(2);
codeStream.Emit(ILOpcode.add);

// (String.Length + 2) * GetMaxDBCSCharByteSize()
codeStream.Emit(ILOpcode.ldsfld, emitter.NewToken(Context.SystemModule.GetKnownType(
"System.Runtime.InteropServices","Marshal")
.GetKnownField("SystemMaxDBCSCharSize")));
codeStream.Emit(ILOpcode.mul_ovf);

// BufSize = (String.Length + 2) * GetMaxDBCSCharByteSize()
codeStream.EmitStLoc(bufSize);

// if (MAX_LOCAL_BUFFER_LENGTH < BufSize ) goto NoOptimize
codeStream.EmitLdc(MAX_LOCAL_BUFFER_LENGTH + 1);
codeStream.EmitLdLoc(bufSize);
codeStream.Emit(ILOpcode.clt);
codeStream.Emit(ILOpcode.brtrue, noOptimize);

// LocalBuffer = localloc(BufSize);
codeStream.EmitLdLoc(bufSize);
codeStream.Emit(ILOpcode.localloc);
codeStream.EmitStLoc(_localBuffer);

// NoOptimize:
codeStream.EmitLabel(noOptimize);
}

int flags = (PInvokeFlags.BestFitMapping ? 0x1 : 0)
| (PInvokeFlags.ThrowOnUnmappableChar ? 0x100 : 0);

// CSTRMarshaler.ConvertToNative pManaged, dwAnsiMarshalFlags, pLocalBuffer
codeStream.EmitLdc(flags);
LoadManagedValue(codeStream);

if (_localBuffer != default)
{
codeStream.EmitLdLoc(_localBuffer);
}
else
{
codeStream.Emit(ILOpcode.ldnull);
}

codeStream.Emit(ILOpcode.call, emitter.NewToken(stringToAnsi));
#else
LoadManagedValue(codeStream);
Expand All @@ -1631,7 +1698,7 @@ protected override void TransformNativeToManaged(ILCodeStream codeStream)

#if READYTORUN
var ansiToString =
Context.SystemModule.GetKnownType("System.StubHelpers", "AnsiBSTRMarshaler")
Context.SystemModule.GetKnownType("System.StubHelpers", "CSTRMarshaler")
.GetKnownMethod("ConvertToManaged", null);
#else
var ansiToString = Context.GetHelperEntryPoint("InteropHelpers", "AnsiStringToString");
Expand All @@ -1645,11 +1712,28 @@ protected override void EmitCleanupManaged(ILCodeStream codeStream)
{
var emitter = _ilCodeStreams.Emitter;
#if READYTORUN
var optimize = emitter.NewCodeLabel();

MethodDesc clearNative =
Context.SystemModule.GetKnownType("System.StubHelpers", "AnsiBSTRMarshaler")
Context.SystemModule.GetKnownType("System.StubHelpers", "CSTRMarshaler")
.GetKnownMethod("ClearNative", null);

if (_localBuffer != default)
{
// if (m_dwLocalBuffer) goto Optimize
codeStream.EmitLdLoc(_localBuffer);
codeStream.Emit(ILOpcode.brtrue, optimize);
}

LoadNativeValue(codeStream);
// static void m_idClearNative(IntPtr ptr)
codeStream.Emit(ILOpcode.call, emitter.NewToken(clearNative));

// Optimize:
if (_localBuffer != default)
{
codeStream.EmitLabel(optimize);
}
#else
var lNullCheck = emitter.NewCodeLabel();

Expand Down