patch-1.3.94 linux/arch/m68k/fpsp040/x_fline.S

• Lines: 105
• Date: Sat Feb 24 22:58:45 1996
• Orig file: v1.3.93/linux/arch/m68k/fpsp040/x_fline.S
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.93/linux/arch/m68k/fpsp040/x_fline.S linux/arch/m68k/fpsp040/x_fline.S
@@ -0,0 +1,104 @@
+|
+|	x_fline.sa 3.3 1/10/91
+|
+|	fpsp_fline --- FPSP handler for fline exception
+|
+|	First determine if the exception is one of the unimplemented
+|	floating point instructions.  If so, let fpsp_unimp handle it.
+|	Next, determine if the instruction is an fmovecr with a non-zero
+|	<ea> field.  If so, handle here and return.  Otherwise, it
+|	must be a real F-line exception.
+|
+
+|		Copyright (C) Motorola, Inc. 1990
+|			All Rights Reserved
+|
+|	THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA 
+|	The copyright notice above does not evidence any  
+|	actual or intended publication of such source code.
+
+X_FLINE:	|idnt    2,1 | Motorola 040 Floating Point Software Package
+
+	|section	8
+
+	.include "fpsp.h"
+
+	|xref	real_fline
+	|xref	fpsp_unimp
+	|xref	uni_2
+	|xref	mem_read
+	|xref	fpsp_fmt_error
+
+	.global	fpsp_fline
+fpsp_fline:
+|
+|	check for unimplemented vector first.  Use EXC_VEC-4 because
+|	the equate is valid only after a 'link a6' has pushed one more
+|	long onto the stack.
+|
+	cmpw	#UNIMP_VEC,EXC_VEC-4(%a7)
+	beql	fpsp_unimp
+
+|
+|	fmovecr with non-zero <ea> handling here
+|
+	subl	#4,%a7		|4 accounts for 2-word difference
+|				;between six word frame (unimp) and
+|				;four word frame
+	link	%a6,#-LOCAL_SIZE
+	fsave	-(%a7)
+	moveml	%d0-%d1/%a0-%a1,USER_DA(%a6)
+	moveal	EXC_PC+4(%a6),%a0	|get address of fline instruction
+	leal	L_SCR1(%a6),%a1	|use L_SCR1 as scratch
+	movel	#4,%d0
+	addl	#4,%a6		|to offset the sub.l #4,a7 above so that
+|				;a6 can point correctly to the stack frame 
+|				;before branching to mem_read
+	bsrl	mem_read
+	subl	#4,%a6
+	movel	L_SCR1(%a6),%d0	|d0 contains the fline and command word
+	bfextu	%d0{#4:#3},%d1	|extract coprocessor id
+	cmpib	#1,%d1		|check if cpid=1
+	bne	not_mvcr	|exit if not
+	bfextu	%d0{#16:#6},%d1
+	cmpib	#0x17,%d1		|check if it is an FMOVECR encoding
+	bne	not_mvcr	
+|				;if an FMOVECR instruction, fix stack
+|				;and go to FPSP_UNIMP
+fix_stack:
+	cmpib	#VER_40,(%a7)	|test for orig unimp frame
+	bnes	ck_rev
+	subl	#UNIMP_40_SIZE-4,%a7 |emulate an orig fsave
+	moveb	#VER_40,(%a7)
+	moveb	#UNIMP_40_SIZE-4,1(%a7)
+	clrw	2(%a7)
+	bras	fix_con
+ck_rev:
+	cmpib	#VER_41,(%a7)	|test for rev unimp frame
+	bnel	fpsp_fmt_error	|if not $40 or $41, exit with error
+	subl	#UNIMP_41_SIZE-4,%a7 |emulate a rev fsave
+	moveb	#VER_41,(%a7)
+	moveb	#UNIMP_41_SIZE-4,1(%a7)
+	clrw	2(%a7)
+fix_con:
+	movew	EXC_SR+4(%a6),EXC_SR(%a6) |move stacked sr to new position
+	movel	EXC_PC+4(%a6),EXC_PC(%a6) |move stacked pc to new position
+	fmovel	EXC_PC(%a6),%FPIAR |point FPIAR to fline inst
+	movel	#4,%d1
+	addl	%d1,EXC_PC(%a6)	|increment stacked pc value to next inst
+	movew	#0x202c,EXC_VEC(%a6) |reformat vector to unimp
+	clrl	EXC_EA(%a6)	|clear the EXC_EA field
+	movew	%d0,CMDREG1B(%a6) |move the lower word into CMDREG1B
+	clrl	E_BYTE(%a6)
+	bsetb	#UFLAG,T_BYTE(%a6)
+	moveml	USER_DA(%a6),%d0-%d1/%a0-%a1 |restore data registers
+	bral	uni_2
+
+not_mvcr:
+	moveml	USER_DA(%a6),%d0-%d1/%a0-%a1 |restore data registers
+	frestore (%a7)+
+	unlk	%a6
+	addl	#4,%a7
+	bral	real_fline
+
+	|end