From 9252fc0e1a9050fc07eaeb862c3943bfbbf0e201 Mon Sep 17 00:00:00 2001
From: Savva Mitrofanov <savvamtr@gmail.com>
Date: Mon, 6 Feb 2023 23:06:26 +0600
Subject: [PATCH] CryptoPkg/IntrinsicLib: Corrects __ashrdi3 and adds __lshrdi3

The ashrdi3 function should do arithmetic shift instead of logic using
sar instruction. Also adds __lshrdi3 implementation to correct build
using LLVM

Signed-off-by: Savva Mitrofanov <savvamtr@gmail.com>
---
 .../IntrinsicLib/Ia32/MathRShiftU64.nasm      | 26 ++++++++++++++++++-
 1 file changed, 25 insertions(+), 1 deletion(-)

diff --git a/CryptoPkg/Library/IntrinsicLib/Ia32/MathRShiftU64.nasm b/CryptoPkg/Library/IntrinsicLib/Ia32/MathRShiftU64.nasm
index 1d51a4dfa3..25a7296648 100644
--- a/CryptoPkg/Library/IntrinsicLib/Ia32/MathRShiftU64.nasm
+++ b/CryptoPkg/Library/IntrinsicLib/Ia32/MathRShiftU64.nasm
@@ -23,6 +23,31 @@
 ;------------------------------------------------------------------------------
 global ASM_PFX(__ashrdi3)
 ASM_PFX(__ashrdi3):
+    cmp cl,0x40
+    jnc ReturnZero
+    cmp cl,0x20
+    jnc CounterMore32
+    shrd eax,edx,cl
+    sar edx,cl
+    ret
+CounterMore32:
+    mov eax,edx
+    xor edx,edx
+    and cl,0x1f
+    sar eax,cl
+    ret
+ReturnZero:
+    xor eax,eax
+    xor edx,edx
+    ret
+
+;------------------------------------------------------------------------------
+;
+; void __cdecl __lshrdi3 (void)
+;
+;------------------------------------------------------------------------------
+global ASM_PFX(__lshrdi3)
+ASM_PFX(__lshrdi3):
     cmp cl,0x40
     jnc _Exit
     cmp cl,0x20
@@ -40,4 +65,3 @@ _Exit:
     xor eax,eax
     xor edx,edx
     ret
-