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FunctionTailcall Function

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Notifies the profiler that the currently executing function is about to perform a tail call to another function.

Note

The FunctionTailcall function is deprecated in .NET Framework version 2.0. It will continue to work, but will incur a performance penalty. Use the FunctionTailcall2 function instead.

Syntax

void __stdcall FunctionTailcall (  
    [in] FunctionID funcID  
);

Parameters

funcID [in] The identifier of the currently executing function that is about to make a tail call.

Remarks

The target function of the tail call will use the current stack frame, and will return directly to the caller of the function that made the tail call. This means that a FunctionLeave callback will not be issued for a function that is the target of a tail call.

The FunctionTailcall function is a callback; you must implement it. The implementation must use the __declspec(naked) storage-class attribute.

The execution engine does not save any registers before calling this function.

  • On entry, you must save all registers that you use, including those in the floating-point unit (FPU).

  • On exit, you must restore the stack by popping off all the parameters that were pushed by its caller.

The implementation of FunctionTailcall should not block because it will delay garbage collection. The implementation should not attempt a garbage collection because the stack may not be in a garbage collection-friendly state. If a garbage collection is attempted, the runtime will block until FunctionTailcall returns.

Also, the FunctionTailcall function must not call into managed code or in any way cause a managed memory allocation.

Requirements

Platforms: See System Requirements.

Header: CorProf.idl

Library: CorGuids.lib

.NET Framework Versions: 1.1, 1.0

See also