JIT: Add basic support for Swift reverse pinvokes - #100018

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jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
Merged

JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
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{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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jakobbotsch deleted the swift-reverse-pinvoke branch March 21, 2024 17:12
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JIT: Add basic support for Swift reverse pinvokes - #100018

Merged
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
Merged

JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotsch

@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

@jakobbotsch
jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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jakobbotsch commented Mar 20, 2024

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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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jakobbotsch deleted the swift-reverse-pinvoke branch March 21, 2024 17:12
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JIT: Add basic support for Swift reverse pinvokes - #100018

Merged
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
Merged

JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

Conversation

@jakobbotsch

@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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JIT: Add basic support for Swift reverse pinvokes - #100018

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jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
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JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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jakobbotsch deleted the swift-reverse-pinvoke branch March 21, 2024 17:12
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
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JIT: Add basic support for Swift reverse pinvokes - #100018

Merged
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
Merged

JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

@jakobbotsch

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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JIT: Add basic support for Swift reverse pinvokes - #100018

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jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
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JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
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{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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jakobbotsch deleted the swift-reverse-pinvoke branch March 21, 2024 17:12
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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JIT: Add basic support for Swift reverse pinvokes - #100018

Merged
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
Merged

JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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jakobbotsch commented Mar 20, 2024

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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

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LGTM, just a few comments. Thanks!

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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jakobbotsch deleted the swift-reverse-pinvoke branch March 21, 2024 17:12
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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
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JIT: Add basic support for Swift reverse pinvokes - #100018

Merged
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke
Mar 21, 2024
Merged

JIT: Add basic support for Swift reverse pinvokes#100018
jakobbotsch merged 16 commits into
dotnet:mainfrom
jakobbotsch:swift-reverse-pinvoke

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@jakobbotschjakobbotsch commented Mar 20, 2024

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Adds very rudimentary support for Swift reverse pinvokes. Since Swift function pointers are based on SwiftSelf also adds basic support for the SwiftSelf parameter. Structs are not supported yet, and neither is SwiftError.

Adds 10 simple tests just so that we have something. I'm going to regenerate these (and probably increase the number to 100) once we have the struct support.

The SwiftSelf parameter is not enregisterable because it is passed in a register that genFnPrologCalleeRegArgs does not handle. I have other plans to rewrite this function in the future (#99286 (comment)), so I didn't want to bother spending time on it here (it is not a trivial extension given how it works).

@ghostghost added the area-CodeGen-coreclr CLR JIT compiler in src/coreclr/src/jit and related components such as SuperPMI label Mar 20, 2024
Comment on lines -1738 to -1743

regType = compiler->GetEightByteType(structDesc, nCnt);
#ifdef DEBUG
regType = compiler->mangleVarArgsType(regType);
assert(genMapRegNumToRegArgNum((nCnt == 0 ? regNum : otherRegNum), regType) != (unsigned)-1);
#endif // DEBUG

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I have removed this assert in a couple of places because I don't think it is asserting anything meaningful. The existence and mapping of genMapRegNumToRegArgNum is really an internal detail of how genFnPrologCalleeRegArgs works, and I expect to be able to remove it once that function is rewritten.

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jakobbotsch marked this pull request as ready for review March 20, 2024 16:36
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jakobbotsch commented Mar 20, 2024

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cc @dotnet/jit-contrib PTAL @amanasifkhalid

FYI @kotlarmilos@matouskozak@jkurdek

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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How does this get returned to the C# side?

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The pinvokes in C# land are passing pointers to the ExceptionDispatchInfo as "self", and then check whether the it was set by this code after the return.

if ((strcmp(className, "SwiftSelf") == 0) && (strcmp(namespaceName, "System.Runtime.InteropServices.Swift") == 0))
{
LclVarDsc* varDsc = varDscInfo->varDsc;
varDsc->SetArgReg(REG_SWIFT_SELF);

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Does this mean that the reg value is loaded into the SwiftSelf argument?

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The JIT can directly reference and use IL locals in its internal IR, and each of the parameter locals are marked with information about how they're passed (in a register or on stack). That's what the code here is doing.

It's ultimately up to the register allocator to decide what register every local is allocated into. For parameter locals LSRA will prefer to keep it in the same register that it was passed in, but it might also be allocated to another register (in which case a move from the initial register is needed in the prolog) or to stack (in which case a store to the stack frame is needed).

The PR here doesn't allow enregistering SwiftSelf so we will always end up keeping it on the stack frame. That's because the case where there are conflicts in the move graph is not yet handled for this register (e.g. we can have cases where the SwiftSelf register x20 needs to go to x0 and x0 needs to go to x20). It needs a bit of work but I was expecting to work on the relevant logic due to another issue, so I will handle both of these when I do that work.

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Ok, thanks for info.

@amanasifkhalidamanasifkhalid left a comment

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LGTM, just a few comments. Thanks!

}
catch (Exception ex)
{
*(ExceptionDispatchInfo*)self.Value = ExceptionDispatchInfo.Capture(ex);

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Once SwiftError works with reverse Pinvoke, I assume we're going to update this error handling to use the SwiftError arg instead, right?

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Yeah, I think that would make sense.

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Although handling it through SwiftError will require allocating a GCHandle, so the current approach will probably end up being simpler.

@@ -0,0 +1,482 @@
#pragma warning disable CS8500

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Do we need the // Licensed to the .NET Foundation under one or more agreements. header comments at the top of these new files?

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Good catch, I should add those.

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I think some of the other interop tests like SwiftAbiStress are missing it too, but feel free to address that in a follow-up PR.

// mechanism passes the address of the return address to a runtime helper
// where it is used to detect tail-call chains.
unsigned lvaRetAddrVar;
unsigned lvaSwiftSelfArg;

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Since all the places where we check lvaSwiftSelfArg are under #ifdef SWIFT_SUPPORT, should we ifdef this, and where we initialize it in Compiler::lvaInit?

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Yeah, I'll do that.

CORINFO_ARG_LIST_HANDLE varList,
CORINFO_SIG_INFO* varSig);

bool lvaInitSpecialSwiftParam(InitVarDscInfo* varDscInfo, CorInfoType type, CORINFO_CLASS_HANDLE typeHnd);

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Based on the naming of this method, I guess we'll be using this to do the SwiftError* type lookup too...

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Yeah, I was thinking that same logic could live here.

}

#ifdef SWIFT_SUPPORT
if ((compiler->lvaSwiftSelfArg != BAD_VAR_NUM) && ((intRegState.rsCalleeRegArgMaskLiveIn & RBM_SWIFT_SELF) != 0))

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Are there situations where lvaSwiftSelfArg is valid, but the reg mask doesn't include the Swift self reg? If not, maybe we should assert that the reg mask includes it if lvaSwiftSelfArg is set.

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Yes, if lvaSwiftSelfArg is dead on entry then it shouldn't be in the live-in set.

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It might be a good idea to run jitstressregs (or a similar pipeline) on this PR

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

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Looks like jitstressregs is failing with the assert genRegMask(argDsc->GetArgReg()) & (RBM_ARG_REGS) in lsrabuild.cpp (log)

Pushed some commits to fix this and address the rest of the feedback.

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/azp run runtime-coreclr jitstress, runtime-coreclr jitstressregs, runtime-coreclr jitstress2-jitstressregs

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Azure Pipelines successfully started running 3 pipeline(s).

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Failures are #100035, #99810, #100047

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jakobbotsch merged commit de774ff into dotnet:mainMar 21, 2024
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jakobbotsch deleted the swift-reverse-pinvoke branch March 21, 2024 17:12
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