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linux-2.4.29操作系统的源码

	;;
	stf.spill.nta [loc2]=f120,-256
	stf.spill.nta [loc3]=f112,-256
	;;
	stf.spill.nta [loc2]=f104,-256
	stf.spill.nta [loc3]=f96,-256
	;;
	stf.spill.nta [loc2]=f88,-256
	stf.spill.nta [loc3]=f80,-256
	;;
	stf.spill.nta [loc2]=f72,-256
	stf.spill.nta [loc3]=f64,-256
	;;
	stf.spill.nta [loc2]=f56,-256
	stf.spill.nta [loc3]=f48,-256
	;;
	stf.spill.nta [loc2]=f40
	stf.spill.nta [loc3]=f32
	br.ret.sptk.many rp
END(__ia64_save_fpu)

GLOBAL_ENTRY(__ia64_load_fpu)
	alloc r2=ar.pfs,1,2,0,0
	adds r3=128,in0
	adds r14=256,in0
	adds r15=384,in0
	mov loc0=512
	mov loc1=-1024+16
	;;
	ldf.fill.nta f32=[in0],loc0
	ldf.fill.nta f40=[ r3],loc0
	ldf.fill.nta f48=[r14],loc0
	ldf.fill.nta f56=[r15],loc0
	;;
	ldf.fill.nta f64=[in0],loc0
	ldf.fill.nta f72=[ r3],loc0
	ldf.fill.nta f80=[r14],loc0
	ldf.fill.nta f88=[r15],loc0
	;;
	ldf.fill.nta f96=[in0],loc1
	ldf.fill.nta f104=[ r3],loc1
	ldf.fill.nta f112=[r14],loc1
	ldf.fill.nta f120=[r15],loc1
	;;
	ldf.fill.nta f33=[in0],loc0
	ldf.fill.nta f41=[ r3],loc0
	ldf.fill.nta f49=[r14],loc0
	ldf.fill.nta f57=[r15],loc0
	;;
	ldf.fill.nta f65=[in0],loc0
	ldf.fill.nta f73=[ r3],loc0
	ldf.fill.nta f81=[r14],loc0
	ldf.fill.nta f89=[r15],loc0
	;;
	ldf.fill.nta f97=[in0],loc1
	ldf.fill.nta f105=[ r3],loc1
	ldf.fill.nta f113=[r14],loc1
	ldf.fill.nta f121=[r15],loc1
	;;
	ldf.fill.nta f34=[in0],loc0
	ldf.fill.nta f42=[ r3],loc0
	ldf.fill.nta f50=[r14],loc0
	ldf.fill.nta f58=[r15],loc0
	;;
	ldf.fill.nta f66=[in0],loc0
	ldf.fill.nta f74=[ r3],loc0
	ldf.fill.nta f82=[r14],loc0
	ldf.fill.nta f90=[r15],loc0
	;;
	ldf.fill.nta f98=[in0],loc1
	ldf.fill.nta f106=[ r3],loc1
	ldf.fill.nta f114=[r14],loc1
	ldf.fill.nta f122=[r15],loc1
	;;
	ldf.fill.nta f35=[in0],loc0
	ldf.fill.nta f43=[ r3],loc0
	ldf.fill.nta f51=[r14],loc0
	ldf.fill.nta f59=[r15],loc0
	;;
	ldf.fill.nta f67=[in0],loc0
	ldf.fill.nta f75=[ r3],loc0
	ldf.fill.nta f83=[r14],loc0
	ldf.fill.nta f91=[r15],loc0
	;;
	ldf.fill.nta f99=[in0],loc1
	ldf.fill.nta f107=[ r3],loc1
	ldf.fill.nta f115=[r14],loc1
	ldf.fill.nta f123=[r15],loc1
	;;
	ldf.fill.nta f36=[in0],loc0
	ldf.fill.nta f44=[ r3],loc0
	ldf.fill.nta f52=[r14],loc0
	ldf.fill.nta f60=[r15],loc0
	;;
	ldf.fill.nta f68=[in0],loc0
	ldf.fill.nta f76=[ r3],loc0
	ldf.fill.nta f84=[r14],loc0
	ldf.fill.nta f92=[r15],loc0
	;;
	ldf.fill.nta f100=[in0],loc1
	ldf.fill.nta f108=[ r3],loc1
	ldf.fill.nta f116=[r14],loc1
	ldf.fill.nta f124=[r15],loc1
	;;
	ldf.fill.nta f37=[in0],loc0
	ldf.fill.nta f45=[ r3],loc0
	ldf.fill.nta f53=[r14],loc0
	ldf.fill.nta f61=[r15],loc0
	;;
	ldf.fill.nta f69=[in0],loc0
	ldf.fill.nta f77=[ r3],loc0
	ldf.fill.nta f85=[r14],loc0
	ldf.fill.nta f93=[r15],loc0
	;;
	ldf.fill.nta f101=[in0],loc1
	ldf.fill.nta f109=[ r3],loc1
	ldf.fill.nta f117=[r14],loc1
	ldf.fill.nta f125=[r15],loc1
	;;
	ldf.fill.nta f38 =[in0],loc0
	ldf.fill.nta f46 =[ r3],loc0
	ldf.fill.nta f54 =[r14],loc0
	ldf.fill.nta f62 =[r15],loc0
	;;
	ldf.fill.nta f70 =[in0],loc0
	ldf.fill.nta f78 =[ r3],loc0
	ldf.fill.nta f86 =[r14],loc0
	ldf.fill.nta f94 =[r15],loc0
	;;
	ldf.fill.nta f102=[in0],loc1
	ldf.fill.nta f110=[ r3],loc1
	ldf.fill.nta f118=[r14],loc1
	ldf.fill.nta f126=[r15],loc1
	;;
	ldf.fill.nta f39 =[in0],loc0
	ldf.fill.nta f47 =[ r3],loc0
	ldf.fill.nta f55 =[r14],loc0
	ldf.fill.nta f63 =[r15],loc0
	;;
	ldf.fill.nta f71 =[in0],loc0
	ldf.fill.nta f79 =[ r3],loc0
	ldf.fill.nta f87 =[r14],loc0
	ldf.fill.nta f95 =[r15],loc0
	;;
	ldf.fill.nta f103=[in0]
	ldf.fill.nta f111=[ r3]
	ldf.fill.nta f119=[r14]
	ldf.fill.nta f127=[r15]
	br.ret.sptk.many rp
END(__ia64_load_fpu)

GLOBAL_ENTRY(__ia64_init_fpu)
	stf.spill [sp]=f0		// M3
	mov	 f32=f0			// F
	nop.b	 0

	ldfps	 f33,f34=[sp]		// M0
	ldfps	 f35,f36=[sp]		// M1
	mov      f37=f0			// F
	;;

	setf.s	 f38=r0			// M2
	setf.s	 f39=r0			// M3
	mov      f40=f0			// F

	ldfps	 f41,f42=[sp]		// M0
	ldfps	 f43,f44=[sp]		// M1
	mov      f45=f0			// F

	setf.s	 f46=r0			// M2
	setf.s	 f47=r0			// M3
	mov      f48=f0			// F

	ldfps	 f49,f50=[sp]		// M0
	ldfps	 f51,f52=[sp]		// M1
	mov      f53=f0			// F

	setf.s	 f54=r0			// M2
	setf.s	 f55=r0			// M3
	mov      f56=f0			// F

	ldfps	 f57,f58=[sp]		// M0
	ldfps	 f59,f60=[sp]		// M1
	mov      f61=f0			// F

	setf.s	 f62=r0			// M2
	setf.s	 f63=r0			// M3
	mov      f64=f0			// F

	ldfps	 f65,f66=[sp]		// M0
	ldfps	 f67,f68=[sp]		// M1
	mov      f69=f0			// F

	setf.s	 f70=r0			// M2
	setf.s	 f71=r0			// M3
	mov      f72=f0			// F

	ldfps	 f73,f74=[sp]		// M0
	ldfps	 f75,f76=[sp]		// M1
	mov      f77=f0			// F

	setf.s	 f78=r0			// M2
	setf.s	 f79=r0			// M3
	mov      f80=f0			// F

	ldfps	 f81,f82=[sp]		// M0
	ldfps	 f83,f84=[sp]		// M1
	mov      f85=f0			// F

	setf.s	 f86=r0			// M2
	setf.s	 f87=r0			// M3
	mov      f88=f0			// F

	/*
	 * When the instructions are cached, it would be faster to initialize
	 * the remaining registers with simply mov instructions (F-unit).
	 * This gets the time down to ~29 cycles.  However, this would use up
	 * 33 bundles, whereas continuing with the above pattern yields
	 * 10 bundles and ~30 cycles.
	 */

	ldfps	 f89,f90=[sp]		// M0
	ldfps	 f91,f92=[sp]		// M1
	mov      f93=f0			// F

	setf.s	 f94=r0			// M2
	setf.s	 f95=r0			// M3
	mov      f96=f0			// F

	ldfps	 f97,f98=[sp]		// M0
	ldfps	 f99,f100=[sp]		// M1
	mov      f101=f0		// F

	setf.s	 f102=r0		// M2
	setf.s	 f103=r0		// M3
	mov      f104=f0		// F

	ldfps	 f105,f106=[sp]		// M0
	ldfps	 f107,f108=[sp]		// M1
	mov      f109=f0		// F

	setf.s	 f110=r0		// M2
	setf.s	 f111=r0		// M3
	mov      f112=f0		// F

	ldfps	 f113,f114=[sp]		// M0
	ldfps	 f115,f116=[sp]		// M1
	mov      f117=f0		// F

	setf.s	 f118=r0		// M2
	setf.s	 f119=r0		// M3
	mov      f120=f0		// F

	ldfps	 f121,f122=[sp]		// M0
	ldfps	 f123,f124=[sp]		// M1
	mov      f125=f0		// F

	setf.s	 f126=r0		// M2
	setf.s	 f127=r0		// M3
	br.ret.sptk.many rp		// F
END(__ia64_init_fpu)

/*
 * Switch execution mode from virtual to physical
 *
 * Inputs:
 *	r16 = new psr to establish
 *
 * Note: RSE must already be in enforced lazy mode
 */
GLOBAL_ENTRY(ia64_switch_mode_phys)
 {
	alloc r2=ar.pfs,0,0,0,0
	rsm psr.i | psr.ic		// disable interrupts and interrupt collection
	mov r15=ip
 }
	;;
 {
	flushrs				// must be first insn in group
	srlz.i
 }
	;;
	mov cr.ipsr=r16			// set new PSR
	add r3=1f-ia64_switch_mode_phys,r15

	mov r17=ar.bsp
	mov r14=rp			// get return address into a general register
	;;

	// going to physical mode, use tpa to translate virt->phys
	tpa r17=r17
	tpa r3=r3
	tpa sp=sp
	tpa r14=r14
	;;

	mov r18=ar.rnat			// save ar.rnat
	mov ar.bspstore=r17		// this steps on ar.rnat
	mov cr.iip=r3
	mov cr.ifs=r0
	;;
	mov ar.rnat=r18			// restore ar.rnat
	rfi				// must be last insn in group
	;;
1:	mov rp=r14
	br.ret.sptk.many rp
END(ia64_switch_mode_phys)

/*
 * Switch execution mode from physical to virtual
 *
 * Inputs:
 *	r16 = new psr to establish
 *
 * Note: RSE must already be in enforced lazy mode
 */
GLOBAL_ENTRY(ia64_switch_mode_virt)
 {
	alloc r2=ar.pfs,0,0,0,0
	rsm psr.i | psr.ic		// disable interrupts and interrupt collection
	mov r15=ip
 }
	;;
 {
	flushrs				// must be first insn in group
	srlz.i
 }
	;;
	mov cr.ipsr=r16			// set new PSR
	add r3=1f-ia64_switch_mode_virt,r15

	mov r17=ar.bsp
	mov r14=rp			// get return address into a general register
	;;

	// going to virtual
	//   - for code addresses, set upper bits of addr to KERNEL_START
	//   - for stack addresses, set upper 3 bits to 0xe.... Dont change any of the
	//     lower bits since we want it to stay identity mapped
	movl r18=KERNEL_START
	dep r3=0,r3,KERNEL_TR_PAGE_SHIFT,64-KERNEL_TR_PAGE_SHIFT
	dep r14=0,r14,KERNEL_TR_PAGE_SHIFT,64-KERNEL_TR_PAGE_SHIFT
	dep r17=-1,r17,61,3
	dep sp=-1,sp,61,3
	;;
	or r3=r3,r18
	or r14=r14,r18
	;;

	mov r18=ar.rnat			// save ar.rnat
	mov ar.bspstore=r17		// this steps on ar.rnat
	mov cr.iip=r3
	mov cr.ifs=r0
	;;
	mov ar.rnat=r18			// restore ar.rnat
	rfi				// must be last insn in group
	;;
1:	mov rp=r14
	br.ret.sptk.many rp
END(ia64_switch_mode_virt)

#ifdef CONFIG_IA64_BRL_EMU

/*
 *  Assembly routines used by brl_emu.c to set preserved register state.
 */

#define SET_REG(reg)				\
 GLOBAL_ENTRY(ia64_set_##reg);			\
	alloc r16=ar.pfs,1,0,0,0;		\
	mov reg=r32;				\
	;;					\
	br.ret.sptk.many rp;			\
 END(ia64_set_##reg)

SET_REG(b1);
SET_REG(b2);
SET_REG(b3);
SET_REG(b4);
SET_REG(b5);

#endif /* CONFIG_IA64_BRL_EMU */

#ifdef CONFIG_SMP

	/*
	 * This routine handles spinlock contention.  It uses a simple exponential backoff
	 * algorithm to reduce unnecessary bus traffic.  The initial delay is selected from
	 * the low-order bits of the cycle counter (a cheap "randomizer").  I'm sure this
	 * could use additional tuning, especially on systems with a large number of CPUs.
	 * Also, I think the maximum delay should be made a function of the number of CPUs in
	 * the system. --davidm 00/08/05
	 *
	 * WARNING: This is not a normal procedure.  It gets called from C code without
	 * the compiler knowing about it.  Thus, we must not use any scratch registers
	 * beyond those that were declared "clobbered" at the call-site (see spin_lock()
	 * macro).  We may not even use the stacked registers, because that could overwrite
	 * output registers.  Similarly, we can't use the scratch stack area as it may be
	 * in use, too.
	 *
	 * Inputs:
	 *	ar.ccv = 0 (and available for use)
	 *	r28 = available for use
	 *	r29 = available for use
	 *	r30 = non-zero (and available for use)
	 *	r31 = address of lock we're trying to acquire
	 *	p15 = available for use
	 */

#	define delay	r28
#	define timeout	r29
#	define tmp	r30

GLOBAL_ENTRY(ia64_spinlock_contention)
	mov tmp=ar.itc
	;;
	and delay=0x3f,tmp
	;;

.retry:	add timeout=tmp,delay
	shl delay=delay,1
	;;
	dep delay=delay,r0,0,13	// limit delay to 8192 cycles
	;;
	// delay a little...
.wait:	sub tmp=tmp,timeout
#ifdef GAS_HAS_HINT_INSN
	hint @pause
#endif
	or delay=0xf,delay	// make sure delay is non-zero (otherwise we get stuck with 0)
	;;
	cmp.lt p15,p0=tmp,r0
	mov tmp=ar.itc
(p15)	br.cond.sptk .wait
	;;
	ld4 tmp=[r31]
	;;
	cmp.ne p15,p0=tmp,r0
	mov tmp=ar.itc
(p15)	br.cond.sptk .retry	// lock is still busy
	;;
	// try acquiring lock (we know ar.ccv is still zero!):
	mov tmp=1
	;;
	cmpxchg4.acq tmp=[r31],tmp,ar.ccv
	;;
	cmp.eq p15,p0=tmp,r0

	mov tmp=ar.itc
(p15)	br.ret.sptk.many b7	// got lock -> return
	br .retry		// still no luck, retry

END(ia64_spinlock_contention)

#endif