Cleanup unused JIT stubs in vm (#111237)

* Undef JIT_TailCall on non-Windows x86

* JIT_TailCallReturnFromVSD

* JIT_TailCallVSDLeave and JIT_TailCallLeave

* Move JIT_ProfilerEnterLeaveTailcallStub to asm

* GetCONTEXTFromRedirectedStubStackFrame

* RedirectForThrowControl and empty unixstubs

* Update comment mentioning RedirectForThrowControl

* Link to issue for stack probing

* Remove GetCONTEXTFromRedirectedStubStackFrame(T_DISPATCHER_CONTEXT) on all unix

* Remove defines for other archs in Windows specific handler

Author: huoyaoyuan

src/coreclr/debug/ee/debugger.h

@@ -3994,6 +3994,8 @@ HANDLE OpenWin32EventOrThrow(
 // Returns true if the specified IL offset has a special meaning (eg. prolog, etc.)
 bool DbgIsSpecialILOffset(DWORD offset);
 
+#if defined(TARGET_WINDOWS)
 void FixupDispatcherContext(T_DISPATCHER_CONTEXT* pDispatcherContext, T_CONTEXT* pContext, PEXCEPTION_ROUTINE pUnwindPersonalityRoutine = NULL);
+#endif
 
 #endif /* DEBUGGER_H_ */

src/coreclr/jit/lower.cpp

@@ -3411,7 +3411,7 @@ void Lowering::RehomeArgForFastTailCall(unsigned int lclNum,
 //------------------------------------------------------------------------
 // LowerTailCallViaJitHelper: lower a call via the tailcall JIT helper. Morph
 // has already inserted tailcall helper special arguments. This function inserts
-// actual data for some placeholders. This function is only used on x86.
+// actual data for some placeholders. This function is only used on Windows x86.
 //
 // Lower
 //      tail.call(<function args>, int numberOfOldStackArgs, int dummyNumberOfNewStackArgs, int flags, void* dummyArg)

src/coreclr/jit/morph.cpp

@@ -6319,7 +6319,7 @@ void Compiler::fgMorphTailCallViaJitHelper(GenTreeCall* call)
     // For the helper-assisted tail calls, we need to push all the arguments
     // into a single list, and then add a few extra at the beginning or end.
     //
-    // For x86, the tailcall helper is defined as:
+    // For Windows x86, the tailcall helper is defined as:
     //
     //      JIT_TailCall(<function args>, int numberOfOldStackArgsWords, int numberOfNewStackArgsWords, int flags, void*
     //      callTarget)

src/coreclr/vm/CMakeLists.txt

@@ -855,12 +855,6 @@ elseif(CLR_CMAKE_TARGET_ARCH_RISCV64)
     )
 endif()
 
-if(CLR_CMAKE_HOST_UNIX)
-    list(APPEND VM_SOURCES_WKS_ARCH
-        ${ARCH_SOURCES_DIR}/unixstubs.cpp
-    )
-endif(CLR_CMAKE_HOST_UNIX)
-
 set(VM_SOURCES_DAC_ARCH
     exceptionhandling.cpp
 )

src/coreclr/vm/amd64/asmhelpers.S

@@ -44,6 +44,14 @@
 #
 # ***********************************************************
 
+# EXTERN_C void JIT_ProfilerEnterLeaveTailcallStub(UINT_PTR ProfilerHandle);
+# <NOTE>
+#
+# </NOTE>
+LEAF_ENTRY JIT_ProfilerEnterLeaveTailcallStub, _TEXT
+  ret
+LEAF_END JIT_ProfilerEnterLeaveTailcallStub, _TEXT
+
 # EXTERN_C void ProfileEnterNaked(FunctionIDOrClientID functionIDOrClientID, size_t profiledRsp);
 # <NOTE>
 #

src/coreclr/vm/amd64/excepamd64.cpp

@@ -48,12 +48,14 @@ inline PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrameWorker(UINT_PTR establi
     return *ppContext;
 }
 
+#ifdef TARGET_WINDOWS
 PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(DISPATCHER_CONTEXT * pDispatcherContext)
 {
     LIMITED_METHOD_DAC_CONTRACT;
 
     return GetCONTEXTFromRedirectedStubStackFrameWorker(pDispatcherContext->EstablisherFrame);
 }
+#endif // TARGET_WINDOWS
 
 PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(CONTEXT * pContext)
 {
@@ -63,17 +65,14 @@ PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(CONTEXT * pContext)
 }
 
 #if !defined(DACCESS_COMPILE)
-
+#ifdef TARGET_WINDOWS
 FaultingExceptionFrame *GetFrameFromRedirectedStubStackFrame (DISPATCHER_CONTEXT *pDispatcherContext)
 {
     LIMITED_METHOD_CONTRACT;
 
     return (FaultingExceptionFrame*)(pDispatcherContext->EstablisherFrame + THROWSTUB_ESTABLISHER_OFFSET_FaultingExceptionFrame);
 }
-
-#endif // !DACCESS_COMPILE
-
-#if !defined(DACCESS_COMPILE)
+#endif // TARGET_WINDOWS
 
 #define AMD64_SIZE64_PREFIX 0x48
 #define AMD64_ADD_IMM8_OP 0x83

src/coreclr/vm/amd64/excepcpu.h

@@ -40,14 +40,18 @@ EXTERN_C void RedirectForThrowControl();
 // Retrieves the redirected CONTEXT* from the stack frame of one of the
 // RedirectedHandledJITCaseForXXX_Stub's.
 //
+#ifdef TARGET_WINDOWS
 PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(DISPATCHER_CONTEXT * pDispatcherContext);
+#endif // TARGET_WINDOWS
 PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(CONTEXT * pContext);
 
+#ifdef TARGET_WINDOWS
 //
 // Retrieves the FaultingExceptionFrame* from the stack frame of
 // RedirectForThrowControl.
 //
 FaultingExceptionFrame *GetFrameFromRedirectedStubStackFrame (DISPATCHER_CONTEXT *pDispatcherContext);
+#endif // TARGET_WINDOWS
 
 //
 // Functions that wrap RtlVirtualUnwind to make sure that in the AMD64 case all the

src/coreclr/vm/amd64/unixstubs.cpp

@@ -7,15 +7,6 @@
 #include "asmconstants.h"
 #include "virtualcallstub.h"
 
-PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(T_DISPATCHER_CONTEXT * pDispatcherContext)
-{
-    LIMITED_METHOD_DAC_CONTRACT;
-
-    UINT_PTR stackSlot = pDispatcherContext->EstablisherFrame + REDIRECTSTUB_SP_OFFSET_CONTEXT;
-    PTR_PTR_CONTEXT ppContext = dac_cast<PTR_PTR_CONTEXT>((TADDR)stackSlot);
-    return *ppContext;
-}
-
 PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(T_CONTEXT * pContext)
 {
     LIMITED_METHOD_DAC_CONTRACT;
@@ -27,32 +18,6 @@ PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(T_CONTEXT * pContext)
 
 #if !defined(DACCESS_COMPILE)
 
-// The next two functions help retrieve data kept relative to FaultingExceptionFrame that is setup
-// for handling async exceptions (e.g. AV, NullRef, ThreadAbort, etc).
-//
-// FEF (and related data) is available relative to R4 - the thing to be kept in mind is that the
-// DispatcherContext->ContextRecord:
-//
-// 1) represents the caller context in the first pass.
-// 2) represents the current context in the second pass.
-//
-// Since R4 is a non-volatile register, this works for us since we setup the value of R4
-// in the redirection helpers (e.g. RedirectForThreadAbort) but do not
-// change it in their respective callee functions (e.g. RedirectForThreadAbort2)
-// that have the personality routines associated with them (which perform the collided unwind and also
-// invoke the two functions below).
-//
-// Thus, when our personality routine gets called in either passes, DC->ContextRecord->R4 will
-// have the same value.
-
-// Returns the pointer to the FEF
-FaultingExceptionFrame *GetFrameFromRedirectedStubStackFrame (T_DISPATCHER_CONTEXT *pDispatcherContext)
-{
-    LIMITED_METHOD_CONTRACT;
-
-    return (FaultingExceptionFrame*)((TADDR)pDispatcherContext->ContextRecord->R4);
-}
-
 // Returns TRUE if caller should resume execution.
 BOOL
 AdjustContextForVirtualStub(

src/coreclr/vm/arm/exceparm.cpp

@@ -26,15 +26,8 @@ class FaultingExceptionFrame;
 // Retrieves the redirected CONTEXT* from the stack frame of one of the
 // RedirectedHandledJITCaseForXXX_Stub's.
 //
-PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(T_DISPATCHER_CONTEXT * pDispatcherContext);
 PTR_CONTEXT GetCONTEXTFromRedirectedStubStackFrame(T_CONTEXT * pContext);
 
-//
-// Retrieves the FaultingExceptionFrame* from the stack frame of
-// RedirectForThrowControl.
-//
-FaultingExceptionFrame *GetFrameFromRedirectedStubStackFrame (T_DISPATCHER_CONTEXT *pDispatcherContext);
-
 inline
 PCODE GetAdjustedCallAddress(PCODE returnAddress)
 {