ntdll: Store segment registers in x86_64 syscall frame.

dlls/ntdll/unix/signal_x86_64.c

@@ -1945,16 +1945,16 @@ NTSTATUS WINAPI NtGetContextThread( HANDLE handle, CONTEXT *context )
             context->Rbp    = frame->rbp;
             context->Rip    = frame->rip;
             context->EFlags = frame->eflags;
-            __asm__( "movw %%cs,%0" : "=g" (context->SegCs) );
-            __asm__( "movw %%ss,%0" : "=g" (context->SegSs) );
+            context->SegCs  = frame->cs;
+            context->SegSs  = frame->ss;
             context->ContextFlags |= CONTEXT_CONTROL;
         }
         if (needed_flags & CONTEXT_SEGMENTS)
         {
-            __asm__( "movw %%ds,%0" : "=g" (context->SegDs) );
-            __asm__( "movw %%es,%0" : "=g" (context->SegEs) );
-            __asm__( "movw %%fs,%0" : "=g" (context->SegFs) );
-            __asm__( "movw %%gs,%0" : "=g" (context->SegGs) );
+            context->SegDs  = frame->ds;
+            context->SegEs  = frame->es;
+            context->SegFs  = frame->fs;
+            context->SegGs  = frame->gs;
             context->ContextFlags |= CONTEXT_SEGMENTS;
         }
         if (needed_flags & CONTEXT_FLOATING_POINT)

tools/winebuild/import.c

@@ -1529,6 +1529,12 @@ void output_syscalls( DLLSPEC *spec )
             output( "\tmovq %%rbx,-0x28(%%rbp)\n" );
             output( "\tleaq 0x10(%%rbp),%%rbx\n" );
             output( "\tmovq %%rbx,-0x10(%%rbp)\n" );
+            output( "\tmovw %%cs,-0x20(%%rbp)\n" );
+            output( "\tmovw %%ds,-0x1e(%%rbp)\n" );
+            output( "\tmovw %%es,-0x1c(%%rbp)\n" );
+            output( "\tmovw %%fs,-0x1a(%%rbp)\n" );
+            output( "\tmovw %%ss,-0x8(%%rbp)\n" );
+            output( "\tmovw %%gs,-0x6(%%rbp)\n" );
             output( "\tfxsave64 (%%rsp)\n" );
             output( "\tmovq %%gs:0x30,%%rcx\n" );
             output( "\tleaq -0x98(%%rbp),%%rbx\n" );