2 This module contains EBC support routines that are customized based on
5 Copyright (c) 2006 - 2012, Intel Corporation. All rights reserved.<BR>
6 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.
17 #include "EbcExecute.h"
18 #include "EbcSupport.h"
19 #include "EbcDebuggerHook.h"
22 Given raw bytes of Itanium based code, format them into a bundle and
25 @param MemPtr pointer to memory location to write the bundles
27 @param Template 5-bit template.
28 @param Slot0 Instruction slot 0 data for the bundle.
29 @param Slot1 Instruction slot 1 data for the bundle.
30 @param Slot2 Instruction slot 2 data for the bundle.
32 @retval EFI_INVALID_PARAMETER Pointer is not aligned
33 @retval EFI_INVALID_PARAMETER No more than 5 bits in template
34 @retval EFI_INVALID_PARAMETER More than 41 bits used in code
35 @retval EFI_SUCCESS All data is written.
48 Pushes a 64 bit unsigned value to the VM stack.
50 @param VmPtr The pointer to current VM context.
51 @param Arg The value to be pushed.
61 // Advance the VM stack down, and then copy the argument to the stack.
64 VmPtr
->Gpr
[0] -= sizeof (UINT64
);
65 *(UINT64
*) VmPtr
->Gpr
[0] = Arg
;
69 Begin executing an EBC image. The address of the entry point is passed
70 in via a processor register, so we'll need to make a call to get the
73 This is a thunk function. Microsoft x64 compiler only provide fast_call
74 calling convention, so the first four arguments are passed by rcx, rdx,
75 r8, and r9, while other arguments are passed in stack.
77 @param Arg1 The 1st argument.
78 @param ... The variable arguments list.
80 @return The value returned by the EBC application we're going to run.
91 // Create a new VM context on the stack
114 // Get the EBC entry point from the processor register. Make sure you don't
115 // call any functions before this or you could mess up the register the
116 // entry point is passed in.
118 Addr
= EbcLLGetEbcEntryPoint ();
120 // Need the args off the stack.
122 VA_START (List
, Arg1
);
123 Arg2
= VA_ARG (List
, UINT64
);
124 Arg3
= VA_ARG (List
, UINT64
);
125 Arg4
= VA_ARG (List
, UINT64
);
126 Arg5
= VA_ARG (List
, UINT64
);
127 Arg6
= VA_ARG (List
, UINT64
);
128 Arg7
= VA_ARG (List
, UINT64
);
129 Arg8
= VA_ARG (List
, UINT64
);
130 Arg9
= VA_ARG (List
, UINT64
);
131 Arg10
= VA_ARG (List
, UINT64
);
132 Arg11
= VA_ARG (List
, UINT64
);
133 Arg12
= VA_ARG (List
, UINT64
);
134 Arg13
= VA_ARG (List
, UINT64
);
135 Arg14
= VA_ARG (List
, UINT64
);
136 Arg15
= VA_ARG (List
, UINT64
);
137 Arg16
= VA_ARG (List
, UINT64
);
140 // Now clear out our context
142 ZeroMem ((VOID
*) &VmContext
, sizeof (VM_CONTEXT
));
144 // Set the VM instruction pointer to the correct location in memory.
146 VmContext
.Ip
= (VMIP
) Addr
;
148 // Initialize the stack pointer for the EBC. Get the current system stack
149 // pointer and adjust it down by the max needed for the interpreter.
152 // NOTE: Eventually we should have the interpreter allocate memory
153 // for stack space which it will use during its execution. This
154 // would likely improve performance because the interpreter would
155 // no longer be required to test each memory access and adjust
156 // those reading from the stack gap.
158 // For IPF, the stack looks like (assuming 10 args passed)
160 // arg9 (Bottom of high stack)
161 // [ stack gap for interpreter execution ]
162 // [ magic value for detection of stack corruption ]
163 // arg8 (Top of low stack)
166 // [ 64-bit return address ]
168 // If the EBC accesses memory in the stack gap, then we assume that it's
169 // actually trying to access args9 and greater. Therefore we need to
170 // adjust memory accesses in this region to point above the stack gap.
173 // Now adjust the EBC stack pointer down to leave a gap for interpreter
174 // execution. Then stuff a magic value there.
177 Status
= GetEBCStack((EFI_HANDLE
)(UINTN
)-1, &VmContext
.StackPool
, &StackIndex
);
178 if (EFI_ERROR(Status
)) {
181 VmContext
.StackTop
= (UINT8
*)VmContext
.StackPool
+ (STACK_REMAIN_SIZE
);
182 VmContext
.Gpr
[0] = (UINT64
) ((UINT8
*)VmContext
.StackPool
+ STACK_POOL_SIZE
);
183 VmContext
.HighStackBottom
= (UINTN
) VmContext
.Gpr
[0];
184 VmContext
.Gpr
[0] -= sizeof (UINTN
);
187 PushU64 (&VmContext
, (UINT64
) VM_STACK_KEY_VALUE
);
188 VmContext
.StackMagicPtr
= (UINTN
*) VmContext
.Gpr
[0];
189 VmContext
.LowStackTop
= (UINTN
) VmContext
.Gpr
[0];
191 // Push the EBC arguments on the stack. Does not matter that they may not
194 PushU64 (&VmContext
, Arg16
);
195 PushU64 (&VmContext
, Arg15
);
196 PushU64 (&VmContext
, Arg14
);
197 PushU64 (&VmContext
, Arg13
);
198 PushU64 (&VmContext
, Arg12
);
199 PushU64 (&VmContext
, Arg11
);
200 PushU64 (&VmContext
, Arg10
);
201 PushU64 (&VmContext
, Arg9
);
202 PushU64 (&VmContext
, Arg8
);
203 PushU64 (&VmContext
, Arg7
);
204 PushU64 (&VmContext
, Arg6
);
205 PushU64 (&VmContext
, Arg5
);
206 PushU64 (&VmContext
, Arg4
);
207 PushU64 (&VmContext
, Arg3
);
208 PushU64 (&VmContext
, Arg2
);
209 PushU64 (&VmContext
, Arg1
);
211 // Push a bogus return address on the EBC stack because the
212 // interpreter expects one there. For stack alignment purposes on IPF,
213 // EBC return addresses are always 16 bytes. Push a bogus value as well.
215 PushU64 (&VmContext
, 0);
216 PushU64 (&VmContext
, 0xDEADBEEFDEADBEEF);
217 VmContext
.StackRetAddr
= (UINT64
) VmContext
.Gpr
[0];
220 // Begin executing the EBC code
222 EbcDebuggerHookEbcInterpret (&VmContext
);
223 EbcExecute (&VmContext
);
226 // Return the value in Gpr[7] unless there was an error
228 ReturnEBCStack(StackIndex
);
229 return (UINT64
) VmContext
.Gpr
[7];
234 Begin executing an EBC image. The address of the entry point is passed
235 in via a processor register, so we'll need to make a call to get the
238 @param ImageHandle image handle for the EBC application we're executing
239 @param SystemTable standard system table passed into an driver's entry
242 @return The value returned by the EBC application we're going to run.
247 ExecuteEbcImageEntryPoint (
248 IN EFI_HANDLE ImageHandle
,
249 IN EFI_SYSTEM_TABLE
*SystemTable
253 // Create a new VM context on the stack
255 VM_CONTEXT VmContext
;
261 // Get the EBC entry point from the processor register. Make sure you don't
262 // call any functions before this or you could mess up the register the
263 // entry point is passed in.
265 Addr
= EbcLLGetEbcEntryPoint ();
268 // Now clear out our context
270 ZeroMem ((VOID
*) &VmContext
, sizeof (VM_CONTEXT
));
273 // Save the image handle so we can track the thunks created for this image
275 VmContext
.ImageHandle
= ImageHandle
;
276 VmContext
.SystemTable
= SystemTable
;
279 // Set the VM instruction pointer to the correct location in memory.
281 VmContext
.Ip
= (VMIP
) Addr
;
284 // Get the stack pointer. This is the bottom of the upper stack.
287 Status
= GetEBCStack(ImageHandle
, &VmContext
.StackPool
, &StackIndex
);
288 if (EFI_ERROR(Status
)) {
291 VmContext
.StackTop
= (UINT8
*)VmContext
.StackPool
+ (STACK_REMAIN_SIZE
);
292 VmContext
.Gpr
[0] = (UINT64
) ((UINT8
*)VmContext
.StackPool
+ STACK_POOL_SIZE
);
293 VmContext
.HighStackBottom
= (UINTN
) VmContext
.Gpr
[0];
294 VmContext
.Gpr
[0] -= sizeof (UINTN
);
298 // Allocate stack space for the interpreter. Then put a magic value
299 // at the bottom so we can detect stack corruption.
301 PushU64 (&VmContext
, (UINT64
) VM_STACK_KEY_VALUE
);
302 VmContext
.StackMagicPtr
= (UINTN
*) (UINTN
) VmContext
.Gpr
[0];
305 // When we thunk to external native code, we copy the last 8 qwords from
306 // the EBC stack into the processor registers, and adjust the stack pointer
307 // up. If the caller is not passing 8 parameters, then we've moved the
308 // stack pointer up into the stack gap. If this happens, then the caller
309 // can mess up the stack gap contents (in particular our magic value).
310 // Therefore, leave another gap below the magic value. Pick 10 qwords down,
311 // just as a starting point.
313 VmContext
.Gpr
[0] -= 10 * sizeof (UINT64
);
316 // Align the stack pointer such that after pushing the system table,
317 // image handle, and return address on the stack, it's aligned on a 16-byte
318 // boundary as required for IPF.
320 VmContext
.Gpr
[0] &= (INT64
)~0x0f;
321 VmContext
.LowStackTop
= (UINTN
) VmContext
.Gpr
[0];
323 // Simply copy the image handle and system table onto the EBC stack.
324 // Greatly simplifies things by not having to spill the args
326 PushU64 (&VmContext
, (UINT64
) SystemTable
);
327 PushU64 (&VmContext
, (UINT64
) ImageHandle
);
330 // Interpreter assumes 64-bit return address is pushed on the stack.
331 // IPF does not do this so pad the stack accordingly. Also, a
332 // "return address" is 16 bytes as required for IPF stack alignments.
334 PushU64 (&VmContext
, (UINT64
) 0);
335 PushU64 (&VmContext
, (UINT64
) 0x1234567887654321);
336 VmContext
.StackRetAddr
= (UINT64
) VmContext
.Gpr
[0];
339 // Begin executing the EBC code
341 EbcDebuggerHookExecuteEbcImageEntryPoint (&VmContext
);
342 EbcExecute (&VmContext
);
345 // Return the value in Gpr[7] unless there was an error
347 ReturnEBCStack(StackIndex
);
348 return (UINT64
) VmContext
.Gpr
[7];
353 Create thunks for an EBC image entry point, or an EBC protocol service.
355 @param ImageHandle Image handle for the EBC image. If not null, then
356 we're creating a thunk for an image entry point.
357 @param EbcEntryPoint Address of the EBC code that the thunk is to call
358 @param Thunk Returned thunk we create here
359 @param Flags Flags indicating options for creating the thunk
361 @retval EFI_SUCCESS The thunk was created successfully.
362 @retval EFI_INVALID_PARAMETER The parameter of EbcEntryPoint is not 16-bit
364 @retval EFI_OUT_OF_RESOURCES There is not enough memory to created the EBC
366 @retval EFI_BUFFER_TOO_SMALL EBC_THUNK_SIZE is not larger enough.
371 IN EFI_HANDLE ImageHandle
,
372 IN VOID
*EbcEntryPoint
,
380 UINT64 Code
[3]; // Code in a bundle
381 UINT64 RegNum
; // register number for MOVL
382 UINT64 BitI
; // bits of MOVL immediate data
383 UINT64 BitIc
; // bits of MOVL immediate data
384 UINT64 BitImm5c
; // bits of MOVL immediate data
385 UINT64 BitImm9d
; // bits of MOVL immediate data
386 UINT64 BitImm7b
; // bits of MOVL immediate data
387 UINT64 Br
; // branch register for loading and jumping
393 // Check alignment of pointer to EBC code, which must always be aligned
394 // on a 2-byte boundary.
396 if ((UINT32
) (UINTN
) EbcEntryPoint
& 0x01) {
397 return EFI_INVALID_PARAMETER
;
400 // Allocate memory for the thunk. Make the (most likely incorrect) assumption
401 // that the returned buffer is not aligned, so round up to the next
404 Size
= EBC_THUNK_SIZE
+ EBC_THUNK_ALIGNMENT
- 1;
406 Ptr
= AllocatePool (Size
);
409 return EFI_OUT_OF_RESOURCES
;
412 // Save the start address of the buffer.
417 // Make sure it's aligned for code execution. If not, then
420 if ((UINT32
) (UINTN
) Ptr
& (EBC_THUNK_ALIGNMENT
- 1)) {
421 Ptr
= (UINT8
*) (((UINTN
) Ptr
+ (EBC_THUNK_ALIGNMENT
- 1)) &~ (UINT64
) (EBC_THUNK_ALIGNMENT
- 1));
424 // Return the pointer to the thunk to the caller to user as the
425 // image entry point.
427 *Thunk
= (VOID
*) Ptr
;
430 // Clear out the thunk entry
431 // ZeroMem(Ptr, Size);
433 // For IPF, when you do a call via a function pointer, the function pointer
434 // actually points to a function descriptor which consists of a 64-bit
435 // address of the function, followed by a 64-bit gp for the function being
436 // called. See the the Software Conventions and Runtime Architecture Guide
438 // So first off in our thunk, create a descriptor for our actual thunk code.
439 // This means we need to create a pointer to the thunk code (which follows
440 // the descriptor we're going to create), followed by the gp of the Vm
441 // interpret function we're going to eventually execute.
443 Data64Ptr
= (UINT64
*) Ptr
;
446 // Write the function's entry point (which is our thunk code that follows
447 // this descriptor we're creating).
449 *Data64Ptr
= (UINT64
) (Data64Ptr
+ 2);
451 // Get the gp from the descriptor for EbcInterpret and stuff it in our thunk
454 *(Data64Ptr
+ 1) = *(UINT64
*) ((UINT64
*) (UINTN
) EbcInterpret
+ 1);
456 // Advance our thunk data pointer past the descriptor. Since the
457 // descriptor consists of 16 bytes, the pointer is still aligned for
458 // IPF code execution (on 16-byte boundary).
460 Ptr
+= sizeof (UINT64
) * 2;
463 // *************************** MAGIC BUNDLE ********************************
465 // Write magic code bundle for: movl r8 = 0xca112ebcca112ebc to help the VM
466 // to recognize it is a thunk.
468 Addr
= (UINT64
) 0xCA112EBCCA112EBC;
471 // Now generate the code bytes. First is nop.m 0x0
473 Code
[0] = OPCODE_NOP
;
476 // Next is simply Addr[62:22] (41 bits) of the address
478 Code
[1] = RShiftU64 (Addr
, 22) & 0x1ffffffffff;
481 // Extract bits from the address for insertion into the instruction
484 BitI
= RShiftU64 (Addr
, 63) & 0x01;
488 BitIc
= RShiftU64 (Addr
, 21) & 0x01;
490 // imm5c = Addr[20:16] for 5 bits
492 BitImm5c
= RShiftU64 (Addr
, 16) & 0x1F;
494 // imm9d = Addr[15:7] for 9 bits
496 BitImm9d
= RShiftU64 (Addr
, 7) & 0x1FF;
498 // imm7b = Addr[6:0] for 7 bits
500 BitImm7b
= Addr
& 0x7F;
503 // The EBC entry point will be put into r8, so r8 can be used here
504 // temporary. R8 is general register and is auto-serialized.
509 // Next is jumbled data, including opcode and rest of address
511 Code
[2] = LShiftU64 (BitImm7b
, 13);
512 Code
[2] = Code
[2] | LShiftU64 (0x00, 20); // vc
513 Code
[2] = Code
[2] | LShiftU64 (BitIc
, 21);
514 Code
[2] = Code
[2] | LShiftU64 (BitImm5c
, 22);
515 Code
[2] = Code
[2] | LShiftU64 (BitImm9d
, 27);
516 Code
[2] = Code
[2] | LShiftU64 (BitI
, 36);
517 Code
[2] = Code
[2] | LShiftU64 ((UINT64
)MOVL_OPCODE
, 37);
518 Code
[2] = Code
[2] | LShiftU64 ((RegNum
& 0x7F), 6);
520 WriteBundle ((VOID
*) Ptr
, 0x05, Code
[0], Code
[1], Code
[2]);
523 // *************************** FIRST BUNDLE ********************************
525 // Write code bundle for: movl r8 = EBC_ENTRY_POINT so we pass
526 // the ebc entry point in to the interpreter function via a processor
528 // Note -- we could easily change this to pass in a pointer to a structure
529 // that contained, among other things, the EBC image's entry point. But
530 // for now pass it directly.
533 Addr
= (UINT64
) EbcEntryPoint
;
536 // Now generate the code bytes. First is nop.m 0x0
538 Code
[0] = OPCODE_NOP
;
541 // Next is simply Addr[62:22] (41 bits) of the address
543 Code
[1] = RShiftU64 (Addr
, 22) & 0x1ffffffffff;
546 // Extract bits from the address for insertion into the instruction
549 BitI
= RShiftU64 (Addr
, 63) & 0x01;
553 BitIc
= RShiftU64 (Addr
, 21) & 0x01;
555 // imm5c = Addr[20:16] for 5 bits
557 BitImm5c
= RShiftU64 (Addr
, 16) & 0x1F;
559 // imm9d = Addr[15:7] for 9 bits
561 BitImm9d
= RShiftU64 (Addr
, 7) & 0x1FF;
563 // imm7b = Addr[6:0] for 7 bits
565 BitImm7b
= Addr
& 0x7F;
568 // Put the EBC entry point in r8, which is the location of the return value
574 // Next is jumbled data, including opcode and rest of address
576 Code
[2] = LShiftU64 (BitImm7b
, 13);
577 Code
[2] = Code
[2] | LShiftU64 (0x00, 20); // vc
578 Code
[2] = Code
[2] | LShiftU64 (BitIc
, 21);
579 Code
[2] = Code
[2] | LShiftU64 (BitImm5c
, 22);
580 Code
[2] = Code
[2] | LShiftU64 (BitImm9d
, 27);
581 Code
[2] = Code
[2] | LShiftU64 (BitI
, 36);
582 Code
[2] = Code
[2] | LShiftU64 ((UINT64
)MOVL_OPCODE
, 37);
583 Code
[2] = Code
[2] | LShiftU64 ((RegNum
& 0x7F), 6);
585 WriteBundle ((VOID
*) Ptr
, 0x05, Code
[0], Code
[1], Code
[2]);
588 // *************************** NEXT BUNDLE *********************************
590 // Write code bundle for:
591 // movl rx = offset_of(EbcInterpret|ExecuteEbcImageEntryPoint)
593 // Advance pointer to next bundle, then compute the offset from this bundle
594 // to the address of the entry point of the interpreter.
597 if ((Flags
& FLAG_THUNK_ENTRY_POINT
) != 0) {
598 Addr
= (UINT64
) ExecuteEbcImageEntryPoint
;
600 Addr
= (UINT64
) EbcInterpret
;
603 // Indirection on Itanium-based systems
605 Addr
= *(UINT64
*) Addr
;
608 // Now write the code to load the offset into a register
610 Code
[0] = OPCODE_NOP
;
613 // Next is simply Addr[62:22] (41 bits) of the address
615 Code
[1] = RShiftU64 (Addr
, 22) & 0x1ffffffffff;
618 // Extract bits from the address for insertion into the instruction
621 BitI
= RShiftU64 (Addr
, 63) & 0x01;
625 BitIc
= RShiftU64 (Addr
, 21) & 0x01;
627 // imm5c = Addr[20:16] for 5 bits
629 BitImm5c
= RShiftU64 (Addr
, 16) & 0x1F;
631 // imm9d = Addr[15:7] for 9 bits
633 BitImm9d
= RShiftU64 (Addr
, 7) & 0x1FF;
635 // imm7b = Addr[6:0] for 7 bits
637 BitImm7b
= Addr
& 0x7F;
640 // Put it in r31, a scratch register
645 // Next is jumbled data, including opcode and rest of address
647 Code
[2] = LShiftU64(BitImm7b
, 13);
648 Code
[2] = Code
[2] | LShiftU64 (0x00, 20); // vc
649 Code
[2] = Code
[2] | LShiftU64 (BitIc
, 21);
650 Code
[2] = Code
[2] | LShiftU64 (BitImm5c
, 22);
651 Code
[2] = Code
[2] | LShiftU64 (BitImm9d
, 27);
652 Code
[2] = Code
[2] | LShiftU64 (BitI
, 36);
653 Code
[2] = Code
[2] | LShiftU64 ((UINT64
)MOVL_OPCODE
, 37);
654 Code
[2] = Code
[2] | LShiftU64 ((RegNum
& 0x7F), 6);
656 WriteBundle ((VOID
*) Ptr
, 0x05, Code
[0], Code
[1], Code
[2]);
659 // *************************** NEXT BUNDLE *********************************
661 // Load branch register with EbcInterpret() function offset from the bundle
662 // address: mov b6 = RegNum
664 // See volume 3 page 4-29 of the Arch. Software Developer's Manual.
666 // Advance pointer to next bundle
669 Code
[0] = OPCODE_NOP
;
670 Code
[1] = OPCODE_NOP
;
671 Code
[2] = OPCODE_MOV_BX_RX
;
674 // Pick a branch register to use. Then fill in the bits for the branch
675 // register and user register (same user register as previous bundle).
678 Code
[2] |= LShiftU64 (Br
, 6);
679 Code
[2] |= LShiftU64 (RegNum
, 13);
680 WriteBundle ((VOID
*) Ptr
, 0x0d, Code
[0], Code
[1], Code
[2]);
683 // *************************** NEXT BUNDLE *********************************
685 // Now do the branch: (p0) br.cond.sptk.few b6
687 // Advance pointer to next bundle.
688 // Fill in the bits for the branch register (same reg as previous bundle)
691 Code
[0] = OPCODE_NOP
;
692 Code
[1] = OPCODE_NOP
;
693 Code
[2] = OPCODE_BR_COND_SPTK_FEW
;
694 Code
[2] |= LShiftU64 (Br
, 13);
695 WriteBundle ((VOID
*) Ptr
, 0x1d, Code
[0], Code
[1], Code
[2]);
698 // Add the thunk to our list of allocated thunks so we can do some cleanup
699 // when the image is unloaded. Do this last since the Add function flushes
700 // the instruction cache for us.
702 EbcAddImageThunk (ImageHandle
, (VOID
*) ThunkBase
, ThunkSize
);
712 Given raw bytes of Itanium based code, format them into a bundle and
715 @param MemPtr pointer to memory location to write the bundles
717 @param Template 5-bit template.
718 @param Slot0 Instruction slot 0 data for the bundle.
719 @param Slot1 Instruction slot 1 data for the bundle.
720 @param Slot2 Instruction slot 2 data for the bundle.
722 @retval EFI_INVALID_PARAMETER Pointer is not aligned
723 @retval EFI_INVALID_PARAMETER No more than 5 bits in template
724 @retval EFI_INVALID_PARAMETER More than 41 bits used in code
725 @retval EFI_SUCCESS All data is written.
743 // Verify pointer is aligned
745 if ((UINT64
) MemPtr
& 0xF) {
746 return EFI_INVALID_PARAMETER
;
749 // Verify no more than 5 bits in template
751 if ((Template
&~0x1F) != 0) {
752 return EFI_INVALID_PARAMETER
;
755 // Verify max of 41 bits used in code
757 if (((Slot0
| Slot1
| Slot2
) &~0x1ffffffffff) != 0) {
758 return EFI_INVALID_PARAMETER
;
761 Low64
= LShiftU64 (Slot1
, 46);
762 Low64
= Low64
| LShiftU64 (Slot0
, 5) | Template
;
764 High64
= RShiftU64 (Slot1
, 18);
765 High64
= High64
| LShiftU64 (Slot2
, 23);
768 // Now write it all out
770 BPtr
= (UINT8
*) MemPtr
;
771 for (Index
= 0; Index
< 8; Index
++) {
772 *BPtr
= (UINT8
) Low64
;
773 Low64
= RShiftU64 (Low64
, 8);
777 for (Index
= 0; Index
< 8; Index
++) {
778 *BPtr
= (UINT8
) High64
;
779 High64
= RShiftU64 (High64
, 8);
788 This function is called to execute an EBC CALLEX instruction.
789 The function check the callee's content to see whether it is common native
790 code or a thunk to another piece of EBC code.
791 If the callee is common native code, use EbcLLCAllEXASM to manipulate,
792 otherwise, set the VM->IP to target EBC code directly to avoid another VM
793 be startup which cost time and stack space.
795 @param VmPtr Pointer to a VM context.
796 @param FuncAddr Callee's address
797 @param NewStackPointer New stack pointer after the call
798 @param FramePtr New frame pointer after the call
799 @param Size The size of call instruction
804 IN VM_CONTEXT
*VmPtr
,
806 IN UINTN NewStackPointer
,
826 // FuncAddr points to the descriptor of the target instructions.
828 CalleeAddr
= *((UINT64
*)FuncAddr
);
831 // Processor specific code to check whether the callee is a thunk to EBC.
833 if (*((UINT64
*)CalleeAddr
) != 0xBCCA000100000005) {
837 if (*((UINT64
*)CalleeAddr
+ 1) != 0x697623C1004A112E) {
842 CodeOne18
= RShiftU64 (*((UINT64
*)CalleeAddr
+ 2), 46) & 0x3FFFF;
843 CodeOne23
= (*((UINT64
*)CalleeAddr
+ 3)) & 0x7FFFFF;
844 CodeTwoI
= RShiftU64 (*((UINT64
*)CalleeAddr
+ 3), 59) & 0x1;
845 CodeTwoIc
= RShiftU64 (*((UINT64
*)CalleeAddr
+ 3), 44) & 0x1;
846 CodeTwo7b
= RShiftU64 (*((UINT64
*)CalleeAddr
+ 3), 36) & 0x7F;
847 CodeTwo5c
= RShiftU64 (*((UINT64
*)CalleeAddr
+ 3), 45) & 0x1F;
848 CodeTwo9d
= RShiftU64 (*((UINT64
*)CalleeAddr
+ 3), 50) & 0x1FF;
850 TargetEbcAddr
= CodeTwo7b
;
851 TargetEbcAddr
= TargetEbcAddr
| LShiftU64 (CodeTwo9d
, 7);
852 TargetEbcAddr
= TargetEbcAddr
| LShiftU64 (CodeTwo5c
, 16);
853 TargetEbcAddr
= TargetEbcAddr
| LShiftU64 (CodeTwoIc
, 21);
854 TargetEbcAddr
= TargetEbcAddr
| LShiftU64 (CodeOne18
, 22);
855 TargetEbcAddr
= TargetEbcAddr
| LShiftU64 (CodeOne23
, 40);
856 TargetEbcAddr
= TargetEbcAddr
| LShiftU64 (CodeTwoI
, 63);
861 // The callee is a thunk to EBC, adjust the stack pointer down 16 bytes and
862 // put our return address and frame pointer on the VM stack.
863 // Then set the VM's IP to new EBC code.
866 VmWriteMemN (VmPtr
, (UINTN
) VmPtr
->Gpr
[0], (UINTN
) FramePtr
);
867 VmPtr
->FramePtr
= (VOID
*) (UINTN
) VmPtr
->Gpr
[0];
869 VmWriteMem64 (VmPtr
, (UINTN
) VmPtr
->Gpr
[0], (UINT64
) (VmPtr
->Ip
+ Size
));
871 VmPtr
->Ip
= (VMIP
) (UINTN
) TargetEbcAddr
;
874 // The callee is not a thunk to EBC, call native code,
875 // and get return value.
877 VmPtr
->Gpr
[7] = EbcLLCALLEXNative (FuncAddr
, NewStackPointer
, FramePtr
);