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#pragma once
#include "Code/Reg.h"
#if defined(WINDOWS) && defined(X64)
namespace code {
namespace eh {
RUNTIME_FUNCTION *exceptionCallback(void *pc, void *base);
}
}
#endif
/**
* Platform-specific defines useful in other places:
*
* Based on documentation from here:
* https://learn.microsoft.com/en-us/cpp/build/exception-handling-x64
*/
namespace code {
namespace eh {
/**
* Same as RUNTIME_FUNCTION in the Win32 headers.
*
* Contents are pointers relative to the start of the image. In our case, the start of the
* image is the start of the allocation made by the active garbage collector.
*/
struct RuntimeFunction {
Nat functionStart;
Nat functionEnd;
Nat unwindInfo;
};
/**
* Same as UNWIND_INFO in Win32 documentation (not present in Win32 headers).
*
* Note: The structure ends with a dynamic part (unwindCodes). This is not a part of the
* structure since it continues with more data afterwards.
*/
struct UnwindInfo {
byte version : 3;
byte flags : 5;
byte prologSize;
byte unwindCount;
byte frameRegister : 4;
byte frameOffset : 4;
// unsigned short unwindCodes[x];
// Nat handlerAddress
};
/**
* Constants for the "flags" in unwind info. Not present in Win32 headers, but we use a
* different name in case they will become available.
*
* UnwindFlagExamine specifies that the handler should be called in the first pass, when
* looking for a handler.
*
* UnwindFlagUnwind specifies that the handler should be called in the second pass, when
* unwinding the stack.
*/
static const byte UnwindFlagExamine = 0x1; // UNW_FLAG_EHANDLER
static const byte UnwindFlagUnwind = 0x2; // UNW_FLAG_UHANDLER
/**
* Unwind operations. Not present in Win32 headers, but uses a different naming scheme in
* case they appear.
*/
static const byte UnwindPushNonvol = 0x0;
static const byte UnwindAllocSmall = 0x2;
static const byte UnwindAllocLarge = 0x1;
/**
* Register numbering on 64-bit Windows.
*/
Nat win64Register(Reg reg);
Reg fromWin64Register(Nat id);
}
}
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