From 2b2705343a810538bc27f5e897da693984c82394 Mon Sep 17 00:00:00 2001
From: Leif Lindholm <quic_llindhol@quicinc.com>
Date: Thu, 1 Oct 2020 19:37:11 +0100
Subject: [PATCH] MdePkg/BaseLib: correct register sizes in AArch64
 SetJump/LongJump

Both in SetJump and in InternalLongJump, 32-bit w register views were
used for the UINTN return value. In SetJump, this did not cause errors;
it was only counterintuitive. But in InternalLongJump, it meant the top
32 bits of Value were stripped off.

Change all of these to use the 64-bit x register views.

Signed-off-by: Leif Lindholm <quic_llindhol@quicinc.com>
Reanimated-by: Andrei Warkentin <andrei.warkentin@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Sami Mujawar <sami.mujawar@arm.com>
Reviewed-by: Andrei Warkentin <andrei.warkentin@intel.com>
---
 MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S   | 8 ++++----
 MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S
index de79ad3a0a..3e58119b25 100644
--- a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S
+++ b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S
@@ -61,7 +61,7 @@ ASM_PFX(SetJump):
         FPR_LAYOUT
 #undef REG_PAIR
 #undef REG_ONE
-        mov     w0, #0
+        mov     x0, #0
         ret
 
 #/**
@@ -91,9 +91,9 @@ ASM_PFX(InternalLongJump):
 #undef REG_PAIR
 #undef REG_ONE
         mov     sp, x16
-        cmp     w1, #0
-        mov     w0, #1
-        csel    w0, w1, w0, ne
+        cmp     x1, #0
+        mov     x0, #1
+        csel    x0, x1, x0, ne
         ret
 
 ASM_FUNCTION_REMOVE_IF_UNREFERENCED
diff --git a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
index c2774eece3..6ec8f35f2c 100644
--- a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
+++ b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
@@ -59,7 +59,7 @@ SetJump
         FPR_LAYOUT
 #undef REG_PAIR
 #undef REG_ONE
-        mov     w0, #0
+        mov     x0, #0
         ret
 
 ;/**
@@ -88,10 +88,10 @@ InternalLongJump
 #undef REG_PAIR
 #undef REG_ONE
         mov     sp, x16
-        cmp     w1, #0
-        mov     w0, #1
+        cmp     x1, #0
+        mov     x0, #1
         beq     exit
-        mov     w0, w1
+        mov     x0, x1
 exit
         // use br not ret, as ret is guaranteed to mispredict
         br      x30