From: naddy <naddy@openbsd.org>
Date: Sun, 4 Jun 2017 23:03:19 +0000 (+0000)
Subject: Catch up with changes made on amd64 (kettenis@):
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=5ffbff1ad788f591009fe26b896b4eeb03a792a0;p=openbsd

Catch up with changes made on amd64 (kettenis@):

Generating mixed 16-bit/32-bit/64-bit code with clang's integrated
assembler is a bit tricky.  It supports the .code16, .code32 and
.code64 directives.  But it doesn't know about the data16/data32 and
addr16/addr32 instruction prefixes.  Instead it tries to determine
those from the instruction opcode.  It mostly succeeds, but there are
a couple of corner cases where clang will generate the "addr32" form
where gas generates the "addr16" form in .code16 segments.  That
should be no problem (and just waste a couple of bytes), but it makes
comparing the generated code a bit difficult.

Allow the trampoline code to be compiled with both.  For clang #define
away the addr32 prefix and avoid using the data32 prefix by using a
mnemonic that explicitly encodes the size of the operand.  Add a few
addr32 prefixes in .code16 blocks to reduce the differences between
code generated by clang and gas.

ok deraadt@
---

diff --git a/sys/arch/i386/i386/acpi_wakecode.S b/sys/arch/i386/i386/acpi_wakecode.S
index 1d722180278..2bda411e4a8 100644
--- a/sys/arch/i386/i386/acpi_wakecode.S
+++ b/sys/arch/i386/i386/acpi_wakecode.S
@@ -52,6 +52,10 @@
 #include <machine/segments.h>
 #include <dev/acpi/acpivar.h>
 
+#ifdef __clang__
+#define addr32
+#endif
+
 #define _ACPI_TRMP_LABEL(a) a = . - _C_LABEL(acpi_real_mode_resume) + ACPI_TRAMPOLINE
 #define _ACPI_TRMP_OFFSET(a) a = . - _C_LABEL(acpi_real_mode_resume)
 #define _ACPI_TRMP_DATA_LABEL(a) a = . - _C_LABEL(acpi_tramp_data_start) + \
@@ -108,7 +112,7 @@ _ACPI_TRMP_OFFSET(acpi_s3_vector_real)
 	movw	%ax, %ss
 	movw	%cs, %ax
 	movw	%ax, %es
-	lidtl	clean_idt
+	addr32 lidtl	clean_idt
 
 	/*
 	 * Set up stack to grow down from offset 0x0FFE.
@@ -140,7 +144,7 @@ _ACPI_TRMP_OFFSET(acpi_s3_vector_real)
 	 * to sleep (although on i386, the saved GDT will most likely
 	 * represent something similar based on machine/segment.h).
 	 */
-	data32 addr32 lgdt	tmp_gdt
+	addr32 lgdtl	tmp_gdt
 
 	/*
 	 * Enable protected mode by setting the PE bit in CR0
@@ -342,7 +346,7 @@ _ACPI_TRMP_LABEL(hibernate_resume_vector_3)
 	movw	%ax, %fs
 	movw	%ax, %gs
 	movl	$0x0FFE, %esp
-	lidtl	clean_idt
+	addr32 lidtl	clean_idt
 
 	/* Jump to the S3 resume vector */
 	ljmp	$(_ACPI_RM_CODE_SEG), $acpi_s3_vector_real
diff --git a/sys/arch/i386/i386/mptramp.s b/sys/arch/i386/i386/mptramp.s
index 3a7f94334e1..148a7e852e3 100644
--- a/sys/arch/i386/i386/mptramp.s
+++ b/sys/arch/i386/i386/mptramp.s
@@ -1,4 +1,4 @@
-/*	$OpenBSD: mptramp.s,v 1.20 2017/02/06 01:50:36 mlarkin Exp $	*/
+/*	$OpenBSD: mptramp.s,v 1.21 2017/06/04 23:03:19 naddy Exp $	*/
 
 /*-
  * Copyright (c) 2000 The NetBSD Foundation, Inc.
@@ -84,6 +84,10 @@
 #include <machine/mpbiosvar.h>
 #include <machine/i82489reg.h>
 
+#ifdef __clang__
+#define addr32
+#endif
+
 #define GDTE(a,b)	.byte	0xff,0xff,0x0,0x0,0x0,a,b,0x0
 #define _RELOC(x)	((x) - KERNBASE)
 #define RELOC(x)	_RELOC(_C_LABEL(x))
@@ -115,7 +119,7 @@ _C_LABEL(cpu_spinup_trampoline):
 	movw	%cs, %ax
 	movw	%ax, %es
 	movw	%ax, %ss
-	data32 addr32 lgdt	(gdt_desc)	# load flat descriptor table
+	addr32 lgdtl (gdt_desc)	# load flat descriptor table
 	movl	%cr0, %eax	# get cr0
 	orl	$0x1, %eax	# enable protected mode
 	movl	%eax, %cr0	# doit