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authorqhuang8 <qhuang8@6f19259b-4bc3-4df7-8a09-765794883524>2008-05-30 02:03:15 +0000
committerqhuang8 <qhuang8@6f19259b-4bc3-4df7-8a09-765794883524>2008-05-30 02:03:15 +0000
commitd2e6d78887995a14bb6f0c25266281749b126646 (patch)
treecd1ffc760fb58893e5e6470baba7796973f85048 /MdePkg/Library/BaseLib/X64/SwitchStack.asm
parentfbbe00ad9dd76ee2544324275449e9781e08073b (diff)
downloadedk2-platforms-d2e6d78887995a14bb6f0c25266281749b126646.tar.xz
1. Add comments about reserve space on space according to x64 calling convention
2. Fix comments in SwitchStack as for the x64 calling convention. git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5315 6f19259b-4bc3-4df7-8a09-765794883524
Diffstat (limited to 'MdePkg/Library/BaseLib/X64/SwitchStack.asm')
-rw-r--r--MdePkg/Library/BaseLib/X64/SwitchStack.asm10
1 files changed, 7 insertions, 3 deletions
diff --git a/MdePkg/Library/BaseLib/X64/SwitchStack.asm b/MdePkg/Library/BaseLib/X64/SwitchStack.asm
index 53d1417f0b..380289a2d0 100644
--- a/MdePkg/Library/BaseLib/X64/SwitchStack.asm
+++ b/MdePkg/Library/BaseLib/X64/SwitchStack.asm
@@ -1,6 +1,6 @@
;------------------------------------------------------------------------------
;
-; Copyright (c) 2006, Intel Corporation
+; Copyright (c) 2006 - 2008, Intel Corporation
; All rights reserved. This program and the accompanying materials
; are licensed and made available under the terms and conditions of the BSD License
; which accompanies this distribution. The full text of the license may be found at
@@ -22,12 +22,12 @@
;------------------------------------------------------------------------------
; Routine Description:
;
-; Routine for switching stacks with 1 parameter
+; Routine for switching stacks with 2 parameters
;
; Arguments:
;
; (rcx) EntryPoint - Entry point with new stack.
-; (rdx) Context - Parameter for entry point.
+; (rdx) Context1 - Parameter1 for entry point.
; (r8) Context2 - Parameter2 for entry point.
; (r9) NewStack - Pointer to new stack.
;
@@ -40,6 +40,10 @@ InternalSwitchStack PROC
mov rax, rcx
mov rcx, rdx
mov rdx, r8
+ ;
+ ; Reserve space for register parameters (rcx, rdx, r8 & r9) on the stack,
+ ; in case the callee wishes to spill them.
+ ;
lea rsp, [r9 - 20h]
call rax
InternalSwitchStack ENDP