Added the MC68040 Floating Point Support Package. This was ported

to RTEMS by Eric Norum.  It is freely distributable and was acquired
from the Motorola WWW site.  More info is in the FPSP README.

1 files changed, 277 insertions, 0 deletions

diff --git a/c/src/lib/libcpu/m68k/m68040/fpsp/x_snan.s b/c/src/lib/libcpu/m68k/m68040/fpsp/x_snan.s
new file mode 100644
index 0000000000..a89369e3f3
--- /dev/null
+++ b/c/src/lib/libcpu/m68k/m68040/fpsp/x_snan.s
@@ -0,0 +1,277 @@
+//
+//	x_snan.sa 3.3 7/1/91
+//
+// fpsp_snan --- FPSP handler for signalling NAN exception
+//
+// SNAN for float -> integer conversions (integer conversion of
+// an SNAN) is a non-maskable run-time exception.
+//
+// For trap disabled the 040 does the following:
+// If the dest data format is s, d, or x, then the SNAN bit in the NAN
+// is set to one and the resulting non-signaling NAN (truncated if
+// necessary) is transferred to the dest.  If the dest format is b, w,
+// or l, then garbage is written to the dest (actually the upper 32 bits
+// of the mantissa are sent to the integer unit).
+//
+// For trap enabled the 040 does the following:
+// If the inst is move_out, then the results are the same as for trap 
+// disabled with the exception posted.  If the instruction is not move_
+// out, the dest. is not modified, and the exception is posted.
+//
+
+//		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+//	THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA 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_SNAN:	//idnt    2,1 | Motorola 040 Floating Point Software Package
+
+	|section	8
+
+	.include "fpsp.defs"
+
+	|xref	get_fline
+	|xref	mem_write
+	|xref	real_snan
+	|xref	real_inex
+	|xref	fpsp_done
+	|xref	reg_dest
+
+	.global	fpsp_snan
+fpsp_snan:
+	link		%a6,#-LOCAL_SIZE
+	fsave		-(%a7)
+	moveml		%d0-%d1/%a0-%a1,USER_DA(%a6)
+	fmovemx	%fp0-%fp3,USER_FP0(%a6)
+	fmoveml	%fpcr/%fpsr/%fpiar,USER_FPCR(%a6)
+
+//
+// Check if trap enabled
+//
+	btstb		#snan_bit,FPCR_ENABLE(%a6)
+	bnes		ena		//If enabled, then branch
+
+	bsrl		move_out	//else SNAN disabled
+//
+// It is possible to have an inex1 exception with the
+// snan.  If the inex enable bit is set in the FPCR, and either
+// inex2 or inex1 occurred, we must clean up and branch to the
+// real inex handler.
+//
+ck_inex:
+	moveb	FPCR_ENABLE(%a6),%d0
+	andb	FPSR_EXCEPT(%a6),%d0
+	andib	#0x3,%d0
+	beq	end_snan
+//
+// Inexact enabled and reported, and we must take an inexact exception.
+//
+take_inex:
+	moveb		#INEX_VEC,EXC_VEC+1(%a6)
+	moveml		USER_DA(%a6),%d0-%d1/%a0-%a1
+	fmovemx	USER_FP0(%a6),%fp0-%fp3
+	fmoveml	USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
+	frestore	(%a7)+
+	unlk		%a6
+	bral		real_inex
+//
+// SNAN is enabled.  Check if inst is move_out.
+// Make any corrections to the 040 output as necessary.
+//
+ena:
+	btstb		#5,CMDREG1B(%a6) //if set, inst is move out
+	beq		not_out
+
+	bsrl		move_out
+
+report_snan:
+	moveb		(%a7),VER_TMP(%a6)
+	cmpib		#VER_40,(%a7)	//test for orig unimp frame
+	bnes		ck_rev
+	moveql		#13,%d0		//need to zero 14 lwords
+	bras		rep_con
+ck_rev:
+	moveql		#11,%d0		//need to zero 12 lwords
+rep_con:
+	clrl		(%a7)
+loop1:
+	clrl		-(%a7)		//clear and dec a7
+	dbra		%d0,loop1
+	moveb		VER_TMP(%a6),(%a7) //format a busy frame
+	moveb		#BUSY_SIZE-4,1(%a7)
+	movel		USER_FPSR(%a6),FPSR_SHADOW(%a6)
+	orl		#sx_mask,E_BYTE(%a6)
+	moveml		USER_DA(%a6),%d0-%d1/%a0-%a1
+	fmovemx	USER_FP0(%a6),%fp0-%fp3
+	fmoveml	USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
+	frestore	(%a7)+
+	unlk		%a6
+	bral		real_snan
+//
+// Exit snan handler by expanding the unimp frame into a busy frame
+//
+end_snan:
+	bclrb		#E1,E_BYTE(%a6)
+
+	moveb		(%a7),VER_TMP(%a6)
+	cmpib		#VER_40,(%a7)	//test for orig unimp frame
+	bnes		ck_rev2
+	moveql		#13,%d0		//need to zero 14 lwords
+	bras		rep_con2
+ck_rev2:
+	moveql		#11,%d0		//need to zero 12 lwords
+rep_con2:
+	clrl		(%a7)
+loop2:
+	clrl		-(%a7)		//clear and dec a7
+	dbra		%d0,loop2
+	moveb		VER_TMP(%a6),(%a7) //format a busy frame
+	moveb		#BUSY_SIZE-4,1(%a7) //write busy size
+	movel		USER_FPSR(%a6),FPSR_SHADOW(%a6)
+	orl		#sx_mask,E_BYTE(%a6)
+	moveml		USER_DA(%a6),%d0-%d1/%a0-%a1
+	fmovemx	USER_FP0(%a6),%fp0-%fp3
+	fmoveml	USER_FPCR(%a6),%fpcr/%fpsr/%fpiar
+	frestore	(%a7)+
+	unlk		%a6
+	bral		fpsp_done
+
+//
+// Move_out 
+//
+move_out:
+	movel		EXC_EA(%a6),%a0	//get <ea> from exc frame
+
+	bfextu		CMDREG1B(%a6){#3:#3},%d0 //move rx field to d0{2:0}
+	cmpil		#0,%d0		//check for long
+	beqs		sto_long	//branch if move_out long
+	
+	cmpil		#4,%d0		//check for word
+	beqs		sto_word	//branch if move_out word
+	
+	cmpil		#6,%d0		//check for byte
+	beqs		sto_byte	//branch if move_out byte
+	
+//
+// Not byte, word or long
+//
+	rts
+//	
+// Get the 32 most significant bits of etemp mantissa
+//
+sto_long:
+	movel		ETEMP_HI(%a6),%d1
+	movel		#4,%d0		//load byte count
+//
+// Set signalling nan bit
+//
+	bsetl		#30,%d1			
+//
+// Store to the users destination address
+//
+	tstl		%a0		//check if <ea> is 0
+	beqs		wrt_dn		//destination is a data register
+	
+	movel		%d1,-(%a7)	//move the snan onto the stack
+	movel		%a0,%a1		//load dest addr into a1
+	movel		%a7,%a0		//load src addr of snan into a0
+	bsrl		mem_write	//write snan to user memory
+	movel		(%a7)+,%d1	//clear off stack
+	rts
+//
+// Get the 16 most significant bits of etemp mantissa
+//
+sto_word:
+	movel		ETEMP_HI(%a6),%d1
+	movel		#2,%d0		//load byte count
+//
+// Set signalling nan bit
+//
+	bsetl		#30,%d1			
+//
+// Store to the users destination address
+//
+	tstl		%a0		//check if <ea> is 0
+	beqs		wrt_dn		//destination is a data register
+
+	movel		%d1,-(%a7)	//move the snan onto the stack
+	movel		%a0,%a1		//load dest addr into a1
+	movel		%a7,%a0		//point to low word
+	bsrl		mem_write	//write snan to user memory
+	movel		(%a7)+,%d1	//clear off stack
+	rts
+//
+// Get the 8 most significant bits of etemp mantissa
+//
+sto_byte:
+	movel		ETEMP_HI(%a6),%d1
+	movel		#1,%d0		//load byte count
+//
+// Set signalling nan bit
+//
+	bsetl		#30,%d1			
+//
+// Store to the users destination address
+//
+	tstl		%a0		//check if <ea> is 0
+	beqs		wrt_dn		//destination is a data register
+	movel		%d1,-(%a7)	//move the snan onto the stack
+	movel		%a0,%a1		//load dest addr into a1
+	movel		%a7,%a0		//point to source byte
+	bsrl		mem_write	//write snan to user memory
+	movel		(%a7)+,%d1	//clear off stack
+	rts
+
+//
+//	wrt_dn --- write to a data register
+//
+//	We get here with D1 containing the data to write and D0 the
+//	number of bytes to write: 1=byte,2=word,4=long.
+//
+wrt_dn:
+	movel		%d1,L_SCR1(%a6)	//data
+	movel		%d0,-(%a7)	//size
+	bsrl		get_fline	//returns fline word in d0
+	movel		%d0,%d1
+	andil		#0x7,%d1		//d1 now holds register number
+	movel		(%sp)+,%d0	//get original size
+	cmpil		#4,%d0
+	beqs		wrt_long
+	cmpil		#2,%d0
+	bnes		wrt_byte
+wrt_word:
+	orl		#0x8,%d1
+	bral		reg_dest
+wrt_long:
+	orl		#0x10,%d1
+	bral		reg_dest
+wrt_byte:
+	bral		reg_dest
+//
+// Check if it is a src nan or dst nan
+//
+not_out:
+	movel		DTAG(%a6),%d0	
+	bfextu		%d0{#0:#3},%d0	//isolate dtag in lsbs
+
+	cmpib		#3,%d0		//check for nan in destination
+	bnes		issrc		//destination nan has priority
+dst_nan:
+	btstb		#6,FPTEMP_HI(%a6) //check if dest nan is an snan
+	bnes		issrc		//no, so check source for snan
+	movew		FPTEMP_EX(%a6),%d0
+	bras		cont
+issrc:
+	movew		ETEMP_EX(%a6),%d0
+cont:
+	btstl		#15,%d0		//test for sign of snan
+	beqs		clr_neg
+	bsetb		#neg_bit,FPSR_CC(%a6)
+	bra		report_snan
+clr_neg:
+	bclrb		#neg_bit,FPSR_CC(%a6)
+	bra		report_snan
+
+	|end