+#include "master.hpp"
+
+namespace factor {
+
+typedef unsigned char UBYTE;
+
+const UBYTE UNW_FLAG_EHANDLER = 0x1;
+
+struct UNWIND_INFO {
+ UBYTE Version:3;
+ UBYTE Flags:5;
+ UBYTE SizeOfProlog;
+ UBYTE CountOfCodes;
+ UBYTE FrameRegister:4;
+ UBYTE FrameOffset:4;
+ ULONG ExceptionHandler;
+ ULONG ExceptionData[1];
+};
+
+struct seh_data {
+ UNWIND_INFO unwind_info;
+ RUNTIME_FUNCTION func;
+ UBYTE handler[32];
+};
+
+void factor_vm::c_to_factor_toplevel(cell quot)
+{
+ /* The annoying thing about Win64 SEH is that the offsets in
+ * function tables are 32-bit integers, and the exception handler
+ * itself must reside between the start and end pointers, so
+ * we stick everything at the beginning of the code heap and
+ * generate a small trampoline that jumps to the real
+ * exception handler. */
+
+ seh_data *seh_area = (seh_data *)code->seh_area;
+ cell base = code->seg->start;
+
+ /* Should look at generating this with the Factor assembler */
+
+ /* mov rax,0 */
+ seh_area->handler[0] = 0x48;
+ seh_area->handler[1] = 0xb8;
+ seh_area->handler[2] = 0x0;
+ seh_area->handler[3] = 0x0;
+ seh_area->handler[4] = 0x0;
+ seh_area->handler[5] = 0x0;
+ seh_area->handler[6] = 0x0;
+ seh_area->handler[7] = 0x0;
+ seh_area->handler[8] = 0x0;
+ seh_area->handler[9] = 0x0;
+
+ /* jmp rax */
+ seh_area->handler[10] = 0x48;
+ seh_area->handler[11] = 0xff;
+ seh_area->handler[12] = 0xe0;
+
+ /* Store address of exception handler in the operand of the 'mov' */
+ cell handler = (cell)&factor::exception_handler;
+ memcpy(&seh_area->handler[2],&handler,sizeof(cell));
+
+ UNWIND_INFO *unwind_info = &seh_area->unwind_info;
+ unwind_info->Version = 1;
+ unwind_info->Flags = UNW_FLAG_EHANDLER;
+ unwind_info->SizeOfProlog = 0;
+ unwind_info->CountOfCodes = 0;
+ unwind_info->FrameRegister = 0;
+ unwind_info->FrameOffset = 0;
+ unwind_info->ExceptionHandler = (DWORD)((cell)&seh_area->handler[0] - base);
+ unwind_info->ExceptionData[0] = 0;
+
+ RUNTIME_FUNCTION *func = &seh_area->func;
+ func->BeginAddress = 0;
+ func->EndAddress = (DWORD)(code->seg->end - base);
+ func->UnwindData = (DWORD)((cell)&seh_area->unwind_info - base);
+
+ if(!RtlAddFunctionTable(func,1,base))
+ fatal_error("RtlAddFunctionTable() failed",0);
+
+ c_to_factor(quot);
+
+ if(!RtlDeleteFunctionTable(func))
+ fatal_error("RtlDeleteFunctionTable() failed",0);
+}
+
+}