entry.s

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	reg_restore %r1

	/* strace expects syscall # to be preserved in r20 */
	ldi	__NR_fork,%r20
	bv %r0(%r2)
	STREG	%r20,PT_GR20(%r1)

	/* Set the return value for the child */
child_return:
	BL	schedule_tail, %r2
	nop

	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE-FRAME_SIZE(%r30), %r1
	LDREG	TASK_PT_GR19(%r1),%r2
	b	wrapper_exit
	copy	%r0,%r28

	
	.export sys_clone_wrapper
sys_clone_wrapper:
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
	ldo	TASK_REGS(%r1),%r1	/* get pt regs */
	reg_save %r1
	mfctl	%cr27, %r3
	STREG	%r3, PT_CR27(%r1)

	STREG	%r2,-RP_OFFSET(%r30)
	ldo	FRAME_SIZE(%r30),%r30
#ifdef __LP64__
	ldo	-16(%r30),%r29		/* Reference param save area */
#endif

	STREG	%r2,PT_GR19(%r1)	/* save for child */
	STREG	%r30,PT_GR21(%r1)
	BL	sys_clone,%r2
	copy	%r1,%r24

	b	wrapper_exit
	LDREG	-RP_OFFSET-FRAME_SIZE(%r30),%r2

	.export sys_vfork_wrapper
sys_vfork_wrapper:
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
	ldo	TASK_REGS(%r1),%r1	/* get pt regs */
	reg_save %r1
	mfctl	%cr27, %r3
	STREG	%r3, PT_CR27(%r1)

	STREG	%r2,-RP_OFFSET(%r30)
	ldo	FRAME_SIZE(%r30),%r30
#ifdef __LP64__
	ldo	-16(%r30),%r29		/* Reference param save area */
#endif

	STREG	%r2,PT_GR19(%r1)	/* save for child */
	STREG	%r30,PT_GR21(%r1)

	BL	sys_vfork,%r2
	copy	%r1,%r26

	b	wrapper_exit
	LDREG	-RP_OFFSET-FRAME_SIZE(%r30),%r2

	
	.macro  execve_wrapper execve
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
	ldo	TASK_REGS(%r1),%r1	/* get pt regs */

	/*
	 * Do we need to save/restore r3-r18 here?
	 * I don't think so. why would new thread need old
	 * threads registers?
	 */

	/* %arg0 - %arg3 are already saved for us. */

	STREG %r2,-RP_OFFSET(%r30)
	ldo FRAME_SIZE(%r30),%r30
#ifdef __LP64__
	ldo	-16(%r30),%r29		/* Reference param save area */
#endif
	bl \execve,%r2
	copy %r1,%arg0

	ldo -FRAME_SIZE(%r30),%r30
	LDREG -RP_OFFSET(%r30),%r2

	/* If exec succeeded we need to load the args */

	ldo -1024(%r0),%r1
	cmpb,>>= %r28,%r1,error_\execve
	copy %r2,%r19

error_\execve:
	bv %r0(%r19)
	nop
	.endm

	.export sys_execve_wrapper
	.import sys_execve

sys_execve_wrapper:
	execve_wrapper sys_execve

#ifdef __LP64__
	.export sys32_execve_wrapper
	.import sys32_execve

sys32_execve_wrapper:
	execve_wrapper sys32_execve
#endif

	.export sys_rt_sigreturn_wrapper
sys_rt_sigreturn_wrapper:
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26
	ldo	TASK_REGS(%r26),%r26	/* get pt regs */
	/* Don't save regs, we are going to restore them from sigcontext. */
	STREG	%r2, -RP_OFFSET(%r30)
#ifdef __LP64__
	ldo	FRAME_SIZE(%r30), %r30
	BL	sys_rt_sigreturn,%r2
	ldo	-16(%r30),%r29		/* Reference param save area */
#else
	BL	sys_rt_sigreturn,%r2
	ldo	FRAME_SIZE(%r30), %r30
#endif

	ldo	-FRAME_SIZE(%r30), %r30
	LDREG	-RP_OFFSET(%r30), %r2

	/* FIXME: I think we need to restore a few more things here. */
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
	ldo	TASK_REGS(%r1),%r1	/* get pt regs */
	reg_restore %r1

	/* If the signal was received while the process was blocked on a
	 * syscall, then r2 will take us to syscall_exit; otherwise r2 will
	 * take us to syscall_exit_rfi and on to intr_return.
	 */
	bv	%r0(%r2)
	LDREG	PT_GR28(%r1),%r28  /* reload original r28 for syscall_exit */

	.export sys_sigaltstack_wrapper
sys_sigaltstack_wrapper:
	/* Get the user stack pointer */
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
	ldo	TASK_REGS(%r1),%r24	/* get pt regs */
	LDREG	TASK_PT_GR30(%r24),%r24
	STREG	%r2, -RP_OFFSET(%r30)
#ifdef __LP64__
	ldo	FRAME_SIZE(%r30), %r30
	b,l	do_sigaltstack,%r2
	ldo	-16(%r30),%r29		/* Reference param save area */
#else
	bl	do_sigaltstack,%r2
	ldo	FRAME_SIZE(%r30), %r30
#endif

	ldo	-FRAME_SIZE(%r30), %r30
	LDREG	-RP_OFFSET(%r30), %r2
	bv	%r0(%r2)
	nop

#ifdef __LP64__
	.export sys32_sigaltstack_wrapper
sys32_sigaltstack_wrapper:
	/* Get the user stack pointer */
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r24
	LDREG	TASK_PT_GR30(%r24),%r24
	STREG	%r2, -RP_OFFSET(%r30)
	ldo	FRAME_SIZE(%r30), %r30
	b,l	do_sigaltstack32,%r2
	ldo	-16(%r30),%r29		/* Reference param save area */

	ldo	-FRAME_SIZE(%r30), %r30
	LDREG	-RP_OFFSET(%r30), %r2
	bv	%r0(%r2)
	nop
#endif

	.export sys_rt_sigsuspend_wrapper
sys_rt_sigsuspend_wrapper:
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
	ldo	TASK_REGS(%r1),%r24
	reg_save %r24

	STREG	%r2, -RP_OFFSET(%r30)
#ifdef __LP64__
	ldo	FRAME_SIZE(%r30), %r30
	b,l	sys_rt_sigsuspend,%r2
	ldo	-16(%r30),%r29		/* Reference param save area */
#else
	bl	sys_rt_sigsuspend,%r2
	ldo	FRAME_SIZE(%r30), %r30
#endif

	ldo	-FRAME_SIZE(%r30), %r30
	LDREG	-RP_OFFSET(%r30), %r2

	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30), %r1
	ldo	TASK_REGS(%r1),%r1
	reg_restore %r1

	bv	%r0(%r2)
	nop

	.export syscall_exit
syscall_exit:

	/* NOTE: HP-UX syscalls also come through here
	 * after hpux_syscall_exit fixes up return
	 * values. */

	/* NOTE: Not all syscalls exit this way.  rt_sigreturn will exit
	 * via syscall_exit_rfi if the signal was received while the process
	 * was running.
	 */

	/* save return value now */

	mfctl     %cr30, %r1
	LDREG     TI_TASK(%r1),%r1
	STREG     %r28,TASK_PT_GR28(%r1)

#ifdef CONFIG_HPUX

/* <linux/personality.h> cannot be easily included */
#define PER_HPUX 0x10
	LDREG     TASK_PERSONALITY(%r1),%r19

	/* We can't use "CMPIB<> PER_HPUX" since "im5" field is sign extended */
	ldo	  -PER_HPUX(%r19), %r19
	CMPIB<>,n 0,%r19,1f

	/* Save other hpux returns if personality is PER_HPUX */
	STREG     %r22,TASK_PT_GR22(%r1)
	STREG     %r29,TASK_PT_GR29(%r1)
1:

#endif /* CONFIG_HPUX */

	/* Seems to me that dp could be wrong here, if the syscall involved
	 * calling a module, and nothing got round to restoring dp on return.
	 */
	loadgp

syscall_check_bh:

	/* Check for software interrupts */

	.import irq_stat,data

	load32	irq_stat,%r19

#ifdef CONFIG_SMP
	/* sched.h: int processor */
	/* %r26 is used as scratch register to index into irq_stat[] */
	ldw     TI_CPU-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r26 /* cpu # */

	/* shift left ____cacheline_aligned (aka L1_CACHE_BYTES) bits */
#ifdef __LP64__
	shld	%r26, 6, %r20
#else
	shlw	%r26, 5, %r20
#endif
	add     %r19,%r20,%r19	/* now have &irq_stat[smp_processor_id()] */
#endif /* CONFIG_SMP */

	LDREG   IRQSTAT_SIRQ_PEND(%r19),%r20    /* hardirq.h: unsigned long */
	cmpib,<>,n 0,%r20,syscall_do_softirq /* forward */

syscall_check_resched:

	/* check for reschedule */

	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19	/* long */
	bb,<,n	%r19, 31-TIF_NEED_RESCHED, syscall_do_resched /* forward */

syscall_check_sig:
	LDREG	TI_FLAGS-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r19    /* get ti flags */
	bb,<,n	%r19, 31-TIF_SIGPENDING, syscall_do_signal /* forward */

syscall_restore:
	/* Are we being ptraced? */
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1

	LDREG	TASK_PTRACE(%r1), %r19
	bb,<	%r19,31,syscall_restore_rfi
	nop

	ldo	TASK_PT_FR31(%r1),%r19		   /* reload fpregs */
	rest_fp	%r19

	LDREG	TASK_PT_SAR(%r1),%r19		   /* restore SAR */
	mtsar	%r19

	LDREG	TASK_PT_GR2(%r1),%r2		   /* restore user rp */
	LDREG	TASK_PT_GR19(%r1),%r19
	LDREG   TASK_PT_GR20(%r1),%r20
	LDREG	TASK_PT_GR21(%r1),%r21
	LDREG	TASK_PT_GR22(%r1),%r22
	LDREG	TASK_PT_GR23(%r1),%r23
	LDREG	TASK_PT_GR24(%r1),%r24
	LDREG	TASK_PT_GR25(%r1),%r25
	LDREG	TASK_PT_GR26(%r1),%r26
	LDREG	TASK_PT_GR27(%r1),%r27	   /* restore user dp */
	LDREG	TASK_PT_GR28(%r1),%r28	   /* syscall return value */
	LDREG	TASK_PT_GR29(%r1),%r29
	LDREG	TASK_PT_GR31(%r1),%r31	   /* restore syscall rp */

	/* NOTE: We use rsm/ssm pair to make this operation atomic */
	rsm     PSW_SM_I, %r0
	LDREG   TASK_PT_GR30(%r1),%r30             /* restore user sp */
	mfsp	%sr3,%r1			   /* Get users space id */
	mtsp    %r1,%sr7                           /* Restore sr7 */
	ssm     PSW_SM_I, %r0

	/* Set sr2 to zero for userspace syscalls to work. */
	mtsp	%r0,%sr2 
	mtsp	%r1,%sr4			   /* Restore sr4 */
	mtsp	%r1,%sr5			   /* Restore sr5 */
	mtsp	%r1,%sr6			   /* Restore sr6 */

	depi	3,31,2,%r31			   /* ensure return to user mode. */

#ifdef __LP64__
	/* decide whether to reset the wide mode bit
	 *
	 * For a syscall, the W bit is stored in the lowest bit
	 * of sp.  Extract it and reset W if it is zero */
	extrd,u,*<>	%r30,63,1,%r1
	rsm	PSW_SM_W, %r0
	/* now reset the lowest bit of sp if it was set */
	xor	%r30,%r1,%r30
#endif
	be,n    0(%sr3,%r31)                       /* return to user space */

	/* We have to return via an RFI, so that PSW T and R bits can be set
	 * appropriately.
	 * This sets up pt_regs so we can return via intr_restore, which is not
	 * the most efficient way of doing things, but it works.
	 */
syscall_restore_rfi:
	ldo	-1(%r0),%r2			   /* Set recovery cntr to -1 */
	mtctl	%r2,%cr0			   /*   for immediate trap */
	LDREG	TASK_PT_PSW(%r1),%r2		   /* Get old PSW */
	ldi	0x0b,%r20			   /* Create new PSW */
	depi	-1,13,1,%r20			   /* C, Q, D, and I bits */

	/* The values of PA_SINGLESTEP_BIT and PA_BLOCKSTEP_BIT are
	 * set in include/linux/ptrace.h and converted to PA bitmap
	 * numbers in asm-offsets.c */

	/* if ((%r19.PA_SINGLESTEP_BIT)) { %r20.27=1} */
	extru,=	%r19,PA_SINGLESTEP_BIT,1,%r0
	depi	-1,27,1,%r20			   /* R bit */

	/* if ((%r19.PA_BLOCKSTEP_BIT)) { %r20.7=1} */
	extru,= %r19,PA_BLOCKSTEP_BIT,1,%r0
	depi	-1,7,1,%r20			   /* T bit */

	STREG	%r20,TASK_PT_PSW(%r1)

	/* Always store space registers, since sr3 can be changed (e.g. fork) */

	mfsp    %sr3,%r25
	STREG   %r25,TASK_PT_SR3(%r1)
	STREG   %r25,TASK_PT_SR4(%r1)
	STREG   %r25,TASK_PT_SR5(%r1)
	STREG   %r25,TASK_PT_SR6(%r1)
	STREG   %r25,TASK_PT_SR7(%r1)
	STREG   %r25,TASK_PT_IASQ0(%r1)
	STREG   %r25,TASK_PT_IASQ1(%r1)

	/* XXX W bit??? */
	/* Now if old D bit is clear, it means we didn't save all registers
	 * on syscall entry, so do that now.  This only happens on TRACEME
	 * calls, or if someone attached to us while we were on a syscall.
	 * We could make this more efficient by not saving r3-r18, but
	 * then we wouldn't be able to use the common intr_restore path.
	 * It is only for traced processes anyway, so performance is not
	 * an issue.
	 */
	bb,<	%r2,30,pt_regs_ok		   /* Branch if D set */
	ldo	TASK_REGS(%r1),%r25
	reg_save %r25				   /* Save r3 to r18 */

	/* Save the current sr */
	mfsp	%sr0,%r2
	STREG	%r2,TASK_PT_SR0(%r1)

	/* Save the scratch sr */
	mfsp	%sr1,%r2
	STREG	%r2,TASK_PT_SR1(%r1)

	/* sr2 should be set to zero for userspace syscalls */
	STREG	%r0,TASK_PT_SR2(%r1)

pt_regs_ok:
	LDREG	TASK_PT_GR31(%r1),%r2
	depi	3,31,2,%r2			   /* ensure return to user mode. */
	STREG	%r2,TASK_PT_IAOQ0(%r1)
	ldo	4(%r2),%r2
	STREG	%r2,TASK_PT_IAOQ1(%r1)
	copy	%r25,%r16
	b	intr_restore
	nop

	.import do_softirq,code
syscall_do_softirq:
	bl      do_softirq,%r2
	nop
	/* NOTE: We enable I-bit incase we schedule later,
	 * and we might be going back to userspace if we were
	 * traced. */
	b       syscall_check_resched
	ssm     PSW_SM_I, %r0  /* do_softirq returns with I bit off */

	.import schedule,code
syscall_do_resched:
	BL	schedule,%r2
#ifdef __LP64__
	ldo	-16(%r30),%r29		/* Reference param save area */
#else
	nop
#endif
	b       syscall_check_bh  /* if resched, we start over again */
	nop

	.import do_signal,code
syscall_do_signal:
	/* Save callee-save registers (for sigcontext).
	   FIXME: After this point the process structure should be
	   consistent with all the relevant state of the process
	   before the syscall.  We need to verify this. */
	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1 
	ldo	TASK_REGS(%r1), %r25		/* struct pt_regs *regs */
	reg_save %r25

	ldi	1, %r24				/* unsigned long in_syscall */

#ifdef __LP64__
	ldo	-16(%r30),%r29			/* Reference param save area */
#endif
	BL	do_signal,%r2
	copy	%r0, %r26			/* sigset_t *oldset = NULL */

	LDREG	TI_TASK-THREAD_SZ_ALGN-FRAME_SIZE(%r30),%r1
	ldo	TASK_REGS(%r1), %r20		/* reload pt_regs */
	reg_restore %r20

	b,n     syscall_check_sig

	/*
	 * get_register is used by the non access tlb miss handlers to
	 * copy the value of the general register specified in r8 into
	 * r1. This routine can't be used for shadowed registers, since
	 * the rfir will restore the original value. So, for the shadowed
	 * registers we put a -1 into r1 to indicate that the register
	 * should not be used (the register being copied could also have
	 * a -1 in it, but that is OK, it just means that we will have
	 * to use the slow path instead).
	 */

get_register:
	blr     %r8,%r0
	nop
	bv      %r0(%r25)    /* r0 */
	copy    %r0,%r1
	bv      %r0(%r25)    /* r1 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r2 */
	copy    %r2,%r1
	bv      %r0(%r25)    /* r3 */
	copy    %r3,%r1
	bv      %r0(%r25)    /* r4 */
	copy    %r4,%r1
	bv      %r0(%r25)    /* r5 */
	copy    %r5,%r1
	bv      %r0(%r25)    /* r6 */
	copy    %r6,%r1
	bv      %r0(%r25)    /* r7 */
	copy    %r7,%r1
	bv      %r0(%r25)    /* r8 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r9 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r10 */
	copy    %r10,%r1
	bv      %r0(%r25)    /* r11 */
	copy    %r11,%r1
	bv      %r0(%r25)    /* r12 */
	copy    %r12,%r1
	bv      %r0(%r25)    /* r13 */
	copy    %r13,%r1
	bv      %r0(%r25)    /* r14 */
	copy    %r14,%r1
	bv      %r0(%r25)    /* r15 */
	copy    %r15,%r1
	bv      %r0(%r25)    /* r16 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r17 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r18 */
	copy    %r18,%r1
	bv      %r0(%r25)    /* r19 */
	copy    %r19,%r1
	bv      %r0(%r25)    /* r20 */
	copy    %r20,%r1
	bv      %r0(%r25)    /* r21 */
	copy    %r21,%r1
	bv      %r0(%r25)    /* r22 */
	copy    %r22,%r1
	bv      %r0(%r25)    /* r23 */
	copy    %r23,%r1
	bv      %r0(%r25)    /* r24 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r25 - shadowed */
	ldi     -1,%r1
	bv      %r0(%r25)    /* r26 */
	copy    %r26,%r1
	bv      %r0(%r25)    /* r27 */
	copy    %r27,%r1
	bv      %r0(%r25)    /* r28 */
	copy    %r28,%r1
	bv      %r0(%r25)    /* r29 */
	copy    %r29,%r1
	bv      %r0(%r25)    /* r30 */
	copy    %r30,%r1
	bv      %r0(%r25)    /* r31 */
	copy    %r31,%r1

	/*
	 * set_register is used by the non access tlb miss handlers to
	 * copy the value of r1 into the general register specified in
	 * r8.
	 */

set_register:
	blr     %r8,%r0
	nop
	bv      %r0(%r25)    /* r0 (silly, but it is a place holder) */
	copy    %r1,%r0
	bv      %r0(%r25)    /* r1 */
	copy    %r1,%r1
	bv      %r0(%r25)    /* r2 */
	copy    %r1,%r2
	bv      %r0(%r25)    /* r3 */
	copy    %r1,%r3
	bv      %r0(%r25)    /* r4 */
	copy    %r1,%r4
	bv      %r0(%r25)    /* r5 */
	copy    %r1,%r5
	bv      %r0(%r25)    /* r6 */
	copy    %r1,%r6
	bv      %r0(%r25)    /* r7 */
	copy    %r1,%r7
	bv      %r0(%r25)    /* r8 */
	copy    %r1,%r8
	bv      %r0(%r25)    /* r9 */
	copy    %r1,%r9
	bv      %r0(%r25)    /* r10 */
	copy    %r1,%r10
	bv      %r0(%r25)    /* r11 */
	copy    %r1,%r11
	bv      %r0(%r25)    /* r12 */
	copy    %r1,%r12
	bv      %r0(%r25)    /* r13 */
	copy    %r1,%r13
	bv      %r0(%r25)    /* r14 */
	copy    %r1,%r14
	bv      %r0(%r25)    /* r15 */
	copy    %r1,%r15
	bv      %r0(%r25)    /* r16 */
	copy    %r1,%r16
	bv      %r0(%r25)    /* r17 */
	copy    %r1,%r17
	bv      %r0(%r25)    /* r18 */
	copy    %r1,%r18
	bv      %r0(%r25)    /* r19 */
	copy    %r1,%r19
	bv      %r0(%r25)    /* r20 */
	copy    %r1,%r20
	bv      %r0(%r25)    /* r21 */
	copy    %r1,%r21
	bv      %r0(%r25)    /* r22 */
	copy    %r1,%r22
	bv      %r0(%r25)    /* r23 */
	copy    %r1,%r23
	bv      %r0(%r25)    /* r24 */
	copy    %r1,%r24
	bv      %r0(%r25)    /* r25 */
	copy    %r1,%r25
	bv      %r0(%r25)    /* r26 */
	copy    %r1,%r26
	bv      %r0(%r25)    /* r27 */
	copy    %r1,%r27
	bv      %r0(%r25)    /* r28 */
	copy    %r1,%r28
	bv      %r0(%r25)    /* r29 */
	copy    %r1,%r29
	bv      %r0(%r25)    /* r30 */
	copy    %r1,%r30
	bv      %r0(%r25)    /* r31 */
	copy    %r1,%r31