From: Tomas Hruby <tom@minix3.org>
Date: Mon, 7 Dec 2009 12:01:05 +0000 (+0000)
Subject: Cooments to warn not to use certains instructions
X-Git-Tag: v3.1.6~166
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/host.html?a=commitdiff_plain;h=51065a1b475e7a7fdab0df5ae2e4490d87717e0e;p=minix.git

Cooments to warn not to use certains instructions

- gas2ack cannot handle all variants of some instructions. Until this issues is
  addressed, this patch places a big warning where appropriate. This code is not
  supposed to change frequently.
---

diff --git a/kernel/arch/i386/klib386.S b/kernel/arch/i386/klib386.S
index affc8e8ae..6e136cc11 100644
--- a/kernel/arch/i386/klib386.S
+++ b/kernel/arch/i386/klib386.S
@@ -549,12 +549,16 @@ fninit:
 
 fnstsw:
 	xor     %eax, %eax
+
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	fnstsw	%ax
 	ret
 
 fnstcw:
 	push    %eax
 	mov     8(%esp), %eax
+
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	fnstcw	(%eax)
 	pop     %eax
 	ret
@@ -599,6 +603,8 @@ read_cr2:
 read_cr4:
 	push	%ebp
 	mov	%esp, %ebp
+
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	mov	%cr4, %eax
 	pop	%ebp
 	ret
@@ -611,6 +617,8 @@ write_cr4:
 	push	%ebp
 	mov	%esp, %ebp
 	mov	8(%ebp), %eax
+
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	mov	%eax, %cr4
 	jmp	0f
 0:
diff --git a/kernel/arch/i386/mpx386.S b/kernel/arch/i386/mpx386.S
index abf7a4929..58351d0b7 100644
--- a/kernel/arch/i386/mpx386.S
+++ b/kernel/arch/i386/mpx386.S
@@ -542,9 +542,12 @@ copr_not_available:
 	mov	%ss:FP_SAVE_AREA_P(%ebp), %eax
 	cmp	$0, osfxsr_feature
 	jz	fp_l_no_fxsr		/* FXSR is not avaible. */
+
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	fxrstor	(%eax)
 	jmp	copr_return
 fp_l_no_fxsr:
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	frstor	(%eax)
 copr_return:
 	orw	$MF_USED_FPU, (%ebx)	/* fpu was used during last execution */
@@ -612,10 +615,13 @@ lazy_fpu:
 	mov	%ss:FP_SAVE_AREA_P(%eax), %eax
 	cmp	$0, osfxsr_feature
 	jz	fp_s_no_fxsr			/* FXSR is not avaible. */
+	
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	fxsave	(%eax)
 	fninit
 	jmp	fp_saved
 fp_s_no_fxsr:
+	/* DO NOT CHANGE THE OPERAND!!! gas2ack does not handle it yet */
 	fnsave	(%eax)
 	fwait	/* required for compatibility with processors prior pentium */
 fp_saved: