From: mdkinney <mdkinney@6f19259b-4bc3-4df7-8a09-765794883524>
Date: Fri, 17 Jul 2009 22:56:34 +0000 (+0000)
Subject: Fix bug in EBC thunk for X64 that appears when higher levels of compiler optimization... 
X-Git-Tag: edk2-stable201903~17343
X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=045e90accdf96b9633cbea6f98b63382481e4f9e

Fix bug in EBC thunk for X64 that appears when higher levels of compiler optimization is used.

This is a temporary fix that should for for most tool chains.  A more complete fix will be required to guarantee compatibility with all tool chains.


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@8970 6f19259b-4bc3-4df7-8a09-765794883524
---

diff --git a/MdeModulePkg/Universal/EbcDxe/X64/EbcLowLevel.asm b/MdeModulePkg/Universal/EbcDxe/X64/EbcLowLevel.asm
index 6741405cbc..2f968cac2f 100644
--- a/MdeModulePkg/Universal/EbcDxe/X64/EbcLowLevel.asm
+++ b/MdeModulePkg/Universal/EbcDxe/X64/EbcLowLevel.asm
@@ -92,6 +92,7 @@ EbcLLCALLEXNative    ENDP
 ;     The contents of the register in which the entry point is passed.
 ;
 EbcLLGetEbcEntryPoint        PROC    PUBLIC
+    mov  rax, r10
     ret
 EbcLLGetEbcEntryPoint    ENDP
 
diff --git a/MdeModulePkg/Universal/EbcDxe/X64/EbcSupport.c b/MdeModulePkg/Universal/EbcDxe/X64/EbcSupport.c
index 3f84bcc496..6c0428d9cc 100644
--- a/MdeModulePkg/Universal/EbcDxe/X64/EbcSupport.c
+++ b/MdeModulePkg/Universal/EbcDxe/X64/EbcSupport.c
@@ -412,14 +412,14 @@ EbcCreateThunks (
 
   //
   // Add code bytes to load up a processor register with the EBC entry point.
-  // mov rax, 123456789abcdef0h  => 48 B8 F0 DE BC 9A 78 56 34 12
+  // mov r10, 123456789abcdef0h  => 48 B8 F0 DE BC 9A 78 56 34 12
   // The first 8 bytes of the thunk entry is the address of the EBC
   // entry point.
   //
-  *Ptr = 0x48;
+  *Ptr = 0x49;
   Ptr++;
   Size--;
-  *Ptr = 0xB8;
+  *Ptr = 0xBA;
   Ptr++;
   Size--;
   Addr = (UINT64) EbcEntryPoint;