2 title VM ASSEMBLY LANGUAGE ROUTINES
3 ;****************************************************************************
5 ;* Copyright (c) 2006 - 2007, Intel Corporation
6 ;* All rights reserved. This program and the accompanying materials
7 ;* are licensed and made available under the terms and conditions of the BSD License
8 ;* which accompanies this distribution. The full text of the license may be found at
9 ;* http://opensource.org/licenses/bsd-license.php
11 ;* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
12 ;* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
14 ;****************************************************************************
15 ;****************************************************************************
17 ;****************************************************************************
19 ; Rev Date Description
20 ; --- -------- ------------------------------------------------------------
21 ; 1.0 03/14/01 Initial creation of file.
23 ;****************************************************************************
25 ;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
26 ; This code provides low level routines that support the Virtual Machine
28 ;* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
30 ;---------------------------------------------------------------------------
31 ; Equate files needed.
32 ;---------------------------------------------------------------------------
38 ;---------------------------------------------------------------------------
40 ;---------------------------------------------------------------------------
45 ;---------------------------------------------------------------------------
46 ;;GenericPostSegment SEGMENT USE16
47 ;---------------------------------------------------------------------------
48 CopyMem PROTO C Destination:PTR DWORD, Source:PTR DWORD, Count:DWORD
50 ;****************************************************************************
53 ; This function is called to execute an EBC CALLEX instruction
55 ; This instruction requires that we thunk out to external native
56 ; code. For IA32, we simply switch stacks and jump to the
57 ; specified function. On return, we restore the stack pointer
58 ; to its original location.
60 ; Destroys no working registers.
61 ;****************************************************************************
62 ; VOID EbcLLCALLEXNative(UINTN FuncAddr, UINTN NewStackPointer, VOID *FramePtr)
63 _EbcLLCALLEXNative PROC NEAR PUBLIC
66 mov ebp, esp ; standard function prolog
68 ; Get function address in a register
69 ; mov ecx, FuncAddr => mov ecx, dword ptr [FuncAddr]
70 mov ecx, dword ptr [esp]+0Ch
72 ; Set stack pointer to new value
73 ; mov eax, NewStackPointer => mov eax, dword ptr [NewSp]
74 mov eax, dword ptr [esp] + 14h
75 mov edx, dword ptr [esp] + 10h
89 ; Now call the external routine
92 ; ebp is preserved by the callee. In this function it
93 ; equals the original esp, so set them equal
96 ; Standard function epilog
101 _EbcLLCALLEXNative ENDP
104 ; UINTN EbcLLGetEbcEntryPoint(VOID);
105 ; Routine Description:
106 ; The VM thunk code stuffs an EBC entry point into a processor
107 ; register. Since we can't use inline assembly to get it from
108 ; the interpreter C code, stuff it into the return value
109 ; register and return.
115 ; The contents of the register in which the entry point is passed.
117 _EbcLLGetEbcEntryPoint PROC NEAR PUBLIC
119 _EbcLLGetEbcEntryPoint ENDP
123 ;Routine Description:
125 ; Return the caller's value of the stack pointer.
133 ; The current value of the stack pointer for the caller. We
134 ; adjust it by 4 here because when they called us, the return address
135 ; is put on the stack, thereby lowering it by 4 bytes.
139 ; UINTN EbcLLGetStackPointer()
140 _EbcLLGetStackPointer PROC NEAR PUBLIC
141 mov eax, esp ; get current stack pointer
142 add eax, 4 ; stack adjusted by this much when we were called
144 _EbcLLGetStackPointer ENDP
146 ; UINT64 EbcLLGetReturnValue(VOID);
147 ; Routine Description:
148 ; When EBC calls native, on return the VM has to stuff the return
149 ; value into a VM register. It's assumed here that the value is still
150 ; in the register, so simply return and the caller should get the
151 ; return result properly.
157 ; The unmodified value returned by the native code.
159 _EbcLLGetReturnValue PROC NEAR PUBLIC
161 _EbcLLGetReturnValue ENDP