Zebediah Figura : ntdll: Avoid depending on compiler support for 64-bit shift functions.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: 9ef7246243ad5446350130bb57b392d688f678ef
URL:    https://source.winehq.org/git/wine.git/?a=commit;h=9ef7246243ad5446350130bb5...

Author: Zebediah Figura 
Date:   Tue Jul  5 21:32:01 2022 -0500

ntdll: Avoid depending on compiler support for 64-bit shift functions.

---

dlls/ntdll/large_int.c | 45 ++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 42 insertions(+), 3 deletions(-)

diff --git a/dlls/ntdll/large_int.c b/dlls/ntdll/large_int.c
index 15716b132a2..038a552545f 100644
--- a/dlls/ntdll/large_int.c
+++ b/dlls/ntdll/large_int.c
@@ -812,7 +812,20 @@ ULONGLONG WINAPI _aulldiv( ULONGLONG a, ULONGLONG b )

LONGLONG __stdcall __regs__allshl( LONGLONG a, unsigned char b )
 {
-    return a << b;
+    const LARGE_INTEGER x = { .QuadPart = a };
+    LARGE_INTEGER ret;
+
+    if (b >= 32)
+    {
+        ret.HighPart = x.LowPart << (b & 31);
+        ret.LowPart = 0;
+    }
+    else
+    {
+        ret.HighPart = (x.LowPart >> (32 - b)) | (x.HighPart << b);
+        ret.LowPart = x.LowPart << b;
+    }
+    return ret.QuadPart;
 }

/******************************************************************************
@@ -828,7 +841,20 @@ __ASM_GLOBAL_FUNC( _allshl,

LONGLONG __stdcall __regs__allshr( LONGLONG a, unsigned char b )
 {
-    return a >> b;
+    const LARGE_INTEGER x = { .QuadPart = a };
+    LARGE_INTEGER ret;
+
+    if (b >= 32)
+    {
+        ret.HighPart = x.HighPart >> 31;
+        ret.LowPart = x.HighPart >> (b & 31);
+    }
+    else
+    {
+        ret.HighPart = x.HighPart >> b;
+        ret.LowPart = (x.HighPart << (32 - b)) | (x.LowPart >> b);
+    }
+    return ret.QuadPart;
 }

/******************************************************************************
@@ -844,7 +870,20 @@ __ASM_GLOBAL_FUNC( _allshr,

ULONGLONG __stdcall __regs__aullshr( ULONGLONG a, unsigned char b )
 {
-    return a >> b;
+    const ULARGE_INTEGER x = { .QuadPart = a };
+    ULARGE_INTEGER ret;
+
+    if (b >= 32)
+    {
+        ret.HighPart = 0;
+        ret.LowPart = x.HighPart >> (b & 31);
+    }
+    else
+    {
+        ret.HighPart = x.HighPart >> b;
+        ret.LowPart = (x.HighPart << (32 - b)) | (x.LowPart >> b);
+    }
+    return ret.QuadPart;
 }

/******************************************************************************