3 ; This code provides low level routines that support the Virtual Machine
6 ; Copyright (c) 2006 - 2008, Intel Corporation. <BR>
7 ; All rights reserved. This program and the accompanying materials
8 ; are licensed and made available under the terms and conditions of the BSD License
9 ; which accompanies this distribution. The full text of the license may be found at
10 ; http://opensource.org/licenses/bsd-license.php
12 ; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
13 ; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
18 title VM ASSEMBLY LANGUAGE ROUTINES
20 ;---------------------------------------------------------------------------
21 ; Equate files needed.
22 ;---------------------------------------------------------------------------
28 ;---------------------------------------------------------------------------
30 ;---------------------------------------------------------------------------
35 ;---------------------------------------------------------------------------
36 ;;GenericPostSegment SEGMENT USE16
37 ;---------------------------------------------------------------------------
38 CopyMem PROTO C Destination:PTR DWORD, Source:PTR DWORD, Count:DWORD
40 ;****************************************************************************
43 ; This function is called to execute an EBC CALLEX instruction
45 ; This instruction requires that we thunk out to external native
46 ; code. For IA32, we simply switch stacks and jump to the
47 ; specified function. On return, we restore the stack pointer
48 ; to its original location.
50 ; Destroys no working registers.
51 ;****************************************************************************
52 ; VOID EbcLLCALLEXNative(UINTN FuncAddr, UINTN NewStackPointer, VOID *FramePtr)
53 _EbcLLCALLEXNative PROC NEAR PUBLIC
56 mov ebp, esp ; standard function prolog
58 ; Get function address in a register
59 ; mov ecx, FuncAddr => mov ecx, dword ptr [FuncAddr]
60 mov ecx, dword ptr [esp]+0Ch
62 ; Set stack pointer to new value
63 ; mov eax, NewStackPointer => mov eax, dword ptr [NewSp]
64 mov eax, dword ptr [esp] + 14h
65 mov edx, dword ptr [esp] + 10h
79 ; Now call the external routine
82 ; ebp is preserved by the callee. In this function it
83 ; equals the original esp, so set them equal
86 ; Standard function epilog
91 _EbcLLCALLEXNative ENDP
94 ; UINTN EbcLLGetEbcEntryPoint(VOID);
95 ; Routine Description:
96 ; The VM thunk code stuffs an EBC entry point into a processor
97 ; register. Since we can't use inline assembly to get it from
98 ; the interpreter C code, stuff it into the return value
99 ; register and return.
105 ; The contents of the register in which the entry point is passed.
107 _EbcLLGetEbcEntryPoint PROC NEAR PUBLIC
109 _EbcLLGetEbcEntryPoint ENDP
113 ;Routine Description:
115 ; Return the caller's value of the stack pointer.
123 ; The current value of the stack pointer for the caller. We
124 ; adjust it by 4 here because when they called us, the return address
125 ; is put on the stack, thereby lowering it by 4 bytes.
129 ; UINTN EbcLLGetStackPointer()
130 _EbcLLGetStackPointer PROC NEAR PUBLIC
131 mov eax, esp ; get current stack pointer
132 add eax, 4 ; stack adjusted by this much when we were called
134 _EbcLLGetStackPointer ENDP
136 ; UINT64 EbcLLGetReturnValue(VOID);
137 ; Routine Description:
138 ; When EBC calls native, on return the VM has to stuff the return
139 ; value into a VM register. It's assumed here that the value is still
140 ; in the register, so simply return and the caller should get the
141 ; return result properly.
147 ; The unmodified value returned by the native code.
149 _EbcLLGetReturnValue PROC NEAR PUBLIC
151 _EbcLLGetReturnValue ENDP