1. Added comments to ASM files

[mirror_edk2.git] / MdePkg / Library / BaseLib / X64 / WriteDr5.asm

diff --git a/MdePkg/Library/BaseLib/X64/WriteDr5.asm b/MdePkg/Library/BaseLib/X64/WriteDr5.asm
index 91eeef20e334dd83019b0ab1d1b8f035f044e5ba..86009c32871d343cb61e728b7065c3e769d1e8ec 100644 (file)
--- a/MdePkg/Library/BaseLib/X64/WriteDr5.asm
+++ b/MdePkg/Library/BaseLib/X64/WriteDr5.asm
@@ -31,6 +31,10 @@
 ;   );\r
 ;------------------------------------------------------------------------------\r
 AsmWriteDr5 PROC\r
+    ;\r
+    ; There's no obvious reason to access this register, since it's aliased to\r
+    ; DR7 when DE=0 or an exception generated when DE=1\r
+    ;\r
     DB      0fh, 23h, 0e9h\r
     mov     rax, rcx\r
     ret\r