svn commit: r290164 - in head/sys/i386: i386 include

[John Baldwin]

Author: jhb
Date: Thu Oct 29 21:25:46 2015
New Revision: 290164
URL: https://svnweb.freebsd.org/changeset/base/290164

Log:
  Use movw instead of movl (or plain mov) when moving segment registers
  into memory.  This is a nop on clang's assembler, but some assemblers
  complain if the size suffix is incorrect.
  
  Submitted by:	bde

Modified:
  head/sys/i386/i386/exception.s
  head/sys/i386/include/asmacros.h

Modified: head/sys/i386/i386/exception.s
==============================================================================
--- head/sys/i386/i386/exception.s	Thu Oct 29 21:12:57 2015	(r290163)
+++ head/sys/i386/i386/exception.s	Thu Oct 29 21:25:46 2015	(r290164)
@@ -158,11 +158,11 @@ IDTVEC(xmm)
 alltraps:
 	pushal
 	pushl	$0
-	movl	%ds,(%esp)
+	movw	%ds,(%esp)
 	pushl	$0
-	movl	%es,(%esp)
+	movw	%es,(%esp)
 	pushl	$0
-	movl	%fs,(%esp)
+	movw	%fs,(%esp)
 alltraps_with_regs_pushed:
 	SET_KERNEL_SREGS
 	cld
@@ -237,11 +237,11 @@ IDTVEC(lcall_syscall)
 	subl	$4,%esp			/* skip over tf_trapno */
 	pushal
 	pushl	$0
-	movl	%ds,(%esp)
+	movw	%ds,(%esp)
 	pushl	$0
-	movl	%es,(%esp)
+	movw	%es,(%esp)
 	pushl	$0
-	movl	%fs,(%esp)
+	movw	%fs,(%esp)
 	SET_KERNEL_SREGS
 	cld
 	FAKE_MCOUNT(TF_EIP(%esp))
@@ -266,11 +266,11 @@ IDTVEC(int0x80_syscall)
 	subl	$4,%esp			/* skip over tf_trapno */
 	pushal
 	pushl	$0
-	movl	%ds,(%esp)
+	movw	%ds,(%esp)
 	pushl	$0
-	movl	%es,(%esp)
+	movw	%es,(%esp)
 	pushl	$0
-	movl	%fs,(%esp)
+	movw	%fs,(%esp)
 	SET_KERNEL_SREGS
 	cld
 	FAKE_MCOUNT(TF_EIP(%esp))
@@ -426,15 +426,15 @@ doreti_iret_fault:
 	subl	$8,%esp
 	pushal
 	pushl	$0
-	movl	%ds,(%esp)
+	movw	%ds,(%esp)
 	.globl	doreti_popl_ds_fault
 doreti_popl_ds_fault:
 	pushl	$0
-	movl	%es,(%esp)
+	movw	%es,(%esp)
 	.globl	doreti_popl_es_fault
 doreti_popl_es_fault:
 	pushl	$0
-	movl	%fs,(%esp)
+	movw	%fs,(%esp)
 	.globl	doreti_popl_fs_fault
 doreti_popl_fs_fault:
 	sti

Modified: head/sys/i386/include/asmacros.h
==============================================================================
--- head/sys/i386/include/asmacros.h	Thu Oct 29 21:12:57 2015	(r290163)
+++ head/sys/i386/include/asmacros.h	Thu Oct 29 21:25:46 2015	(r290164)
@@ -147,11 +147,11 @@
 	pushl	$0 ;		/* dummy trap type */			\
 	pushal ;		/* 8 ints */				\
 	pushl	$0 ;		/* save data and extra segments ... */	\
-	mov	%ds,(%esp) ;						\
+	movw	%ds,(%esp) ;						\
 	pushl	$0 ;							\
-	mov	%es,(%esp) ;						\
+	movw	%es,(%esp) ;						\
 	pushl	$0 ;							\
-	mov	%fs,(%esp)
+	movw	%fs,(%esp)
 	
 #define	POP_FRAME							\
 	popl	%fs ;							\