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diff --git a/c/src/exec/score/cpu/sparc/cpu_asm.s b/c/src/exec/score/cpu/sparc/cpu_asm.s
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--- a/c/src/exec/score/cpu/sparc/cpu_asm.s
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@@ -1,704 +0,0 @@
-/* cpu_asm.s
- *
- * This file contains the basic algorithms for all assembly code used
- * in an specific CPU port of RTEMS. These algorithms must be implemented
- * in assembly language.
- *
- * COPYRIGHT (c) 1989, 1990, 1991, 1992, 1993, 1994.
- * On-Line Applications Research Corporation (OAR).
- * All rights assigned to U.S. Government, 1994.
- *
- * This material may be reproduced by or for the U.S. Government pursuant
- * to the copyright license under the clause at DFARS 252.227-7013. This
- * notice must appear in all copies of this file and its derivatives.
- *
- * Ported to ERC32 implementation of the SPARC by On-Line Applications
- * Research Corporation (OAR) under contract to the European Space
- * Agency (ESA).
- *
- * ERC32 modifications of respective RTEMS file: COPYRIGHT (c) 1995.
- * European Space Agency.
- *
- * $Id$
- */
-
-#include <asm.h>
-#include <rtems/score/cpu.h>
-
-#if (SPARC_HAS_FPU == 1)
-
-/*
- * void _CPU_Context_save_fp(
- * void **fp_context_ptr
- * )
- *
- * This routine is responsible for saving the FP context
- * at *fp_context_ptr. If the point to load the FP context
- * from is changed then the pointer is modified by this routine.
- *
- * NOTE: See the README in this directory for information on the
- * management of the "EF" bit in the PSR.
- */
-
- .align 4
- PUBLIC(_CPU_Context_save_fp)
-SYM(_CPU_Context_save_fp):
- save %sp, -CPU_MINIMUM_STACK_FRAME_SIZE, %sp
-
- /*
- * The following enables the floating point unit.
- */
-
- mov %psr, %l0
- sethi %hi(SPARC_PSR_EF_MASK), %l1
- or %l1, %lo(SPARC_PSR_EF_MASK), %l1
- or %l0, %l1, %l0
- mov %l0, %psr ! **** ENABLE FLOAT ACCESS ****
-
- ld [%i0], %l0
- std %f0, [%l0 + FO_F1_OFFSET]
- std %f2, [%l0 + F2_F3_OFFSET]
- std %f4, [%l0 + F4_F5_OFFSET]
- std %f6, [%l0 + F6_F7_OFFSET]
- std %f8, [%l0 + F8_F9_OFFSET]
- std %f10, [%l0 + F1O_F11_OFFSET]
- std %f12, [%l0 + F12_F13_OFFSET]
- std %f14, [%l0 + F14_F15_OFFSET]
- std %f16, [%l0 + F16_F17_OFFSET]
- std %f18, [%l0 + F18_F19_OFFSET]
- std %f20, [%l0 + F2O_F21_OFFSET]
- std %f22, [%l0 + F22_F23_OFFSET]
- std %f24, [%l0 + F24_F25_OFFSET]
- std %f26, [%l0 + F26_F27_OFFSET]
- std %f28, [%l0 + F28_F29_OFFSET]
- std %f30, [%l0 + F3O_F31_OFFSET]
- st %fsr, [%l0 + FSR_OFFSET]
- ret
- restore
-
-/*
- * void _CPU_Context_restore_fp(
- * void **fp_context_ptr
- * )
- *
- * This routine is responsible for restoring the FP context
- * at *fp_context_ptr. If the point to load the FP context
- * from is changed then the pointer is modified by this routine.
- *
- * NOTE: See the README in this directory for information on the
- * management of the "EF" bit in the PSR.
- */
-
- .align 4
- PUBLIC(_CPU_Context_restore_fp)
-SYM(_CPU_Context_restore_fp):
- save %sp, -CPU_MINIMUM_STACK_FRAME_SIZE , %sp
-
- /*
- * The following enables the floating point unit.
- */
-
- mov %psr, %l0
- sethi %hi(SPARC_PSR_EF_MASK), %l1
- or %l1, %lo(SPARC_PSR_EF_MASK), %l1
- or %l0, %l1, %l0
- mov %l0, %psr ! **** ENABLE FLOAT ACCESS ****
-
- ld [%i0], %l0
- ldd [%l0 + FO_F1_OFFSET], %f0
- ldd [%l0 + F2_F3_OFFSET], %f2
- ldd [%l0 + F4_F5_OFFSET], %f4
- ldd [%l0 + F6_F7_OFFSET], %f6
- ldd [%l0 + F8_F9_OFFSET], %f8
- ldd [%l0 + F1O_F11_OFFSET], %f10
- ldd [%l0 + F12_F13_OFFSET], %f12
- ldd [%l0 + F14_F15_OFFSET], %f14
- ldd [%l0 + F16_F17_OFFSET], %f16
- ldd [%l0 + F18_F19_OFFSET], %f18
- ldd [%l0 + F2O_F21_OFFSET], %f20
- ldd [%l0 + F22_F23_OFFSET], %f22
- ldd [%l0 + F24_F25_OFFSET], %f24
- ldd [%l0 + F26_F27_OFFSET], %f26
- ldd [%l0 + F28_F29_OFFSET], %f28
- ldd [%l0 + F3O_F31_OFFSET], %f30
- ld [%l0 + FSR_OFFSET], %fsr
- ret
- restore
-
-#endif /* SPARC_HAS_FPU */
-
-/*
- * void _CPU_Context_switch(
- * Context_Control *run,
- * Context_Control *heir
- * )
- *
- * This routine performs a normal non-FP context switch.
- */
-
- .align 4
- PUBLIC(_CPU_Context_switch)
-SYM(_CPU_Context_switch):
- ! skip g0
- st %g1, [%o0 + G1_OFFSET] ! save the global registers
- std %g2, [%o0 + G2_OFFSET]
- std %g4, [%o0 + G4_OFFSET]
- std %g6, [%o0 + G6_OFFSET]
-
- std %l0, [%o0 + L0_OFFSET] ! save the local registers
- std %l2, [%o0 + L2_OFFSET]
- std %l4, [%o0 + L4_OFFSET]
- std %l6, [%o0 + L6_OFFSET]
-
- std %i0, [%o0 + I0_OFFSET] ! save the input registers
- std %i2, [%o0 + I2_OFFSET]
- std %i4, [%o0 + I4_OFFSET]
- std %i6, [%o0 + I6_FP_OFFSET]
-
- std %o0, [%o0 + O0_OFFSET] ! save the output registers
- std %o2, [%o0 + O2_OFFSET]
- std %o4, [%o0 + O4_OFFSET]
- std %o6, [%o0 + O6_SP_OFFSET]
-
- rd %psr, %o2
- st %o2, [%o0 + PSR_OFFSET] ! save status register
-
- /*
- * This is entered from _CPU_Context_restore with:
- * o1 = context to restore
- * o2 = psr
- */
-
- PUBLIC(_CPU_Context_restore_heir)
-SYM(_CPU_Context_restore_heir):
- /*
- * Flush all windows with valid contents except the current one.
- * In examining the set register windows, one may logically divide
- * the windows into sets (some of which may be empty) based on their
- * current status:
- *
- * + current (i.e. in use),
- * + used (i.e. a restore would not trap)
- * + invalid (i.e. 1 in corresponding bit in WIM)
- * + unused
- *
- * Either the used or unused set of windows may be empty.
- *
- * NOTE: We assume only one bit is set in the WIM at a time.
- *
- * Given a CWP of 5 and a WIM of 0x1, the registers are divided
- * into sets as follows:
- *
- * + 0 - invalid
- * + 1-4 - unused
- * + 5 - current
- * + 6-7 - used
- *
- * In this case, we only would save the used windows -- 6 and 7.
- *
- * Traps are disabled for the same logical period as in a
- * flush all windows trap handler.
- *
- * Register Usage while saving the windows:
- * g1 = current PSR
- * g2 = current wim
- * g3 = CWP
- * g4 = wim scratch
- * g5 = scratch
- */
-
- ld [%o1 + PSR_OFFSET], %g1 ! g1 = saved psr
-
- and %o2, SPARC_PSR_CWP_MASK, %g3 ! g3 = CWP
- ! g1 = psr w/o cwp
- andn %g1, SPARC_PSR_ET_MASK | SPARC_PSR_CWP_MASK, %g1
- or %g1, %g3, %g1 ! g1 = heirs psr
- mov %g1, %psr ! restore status register and
- ! **** DISABLE TRAPS ****
- mov %wim, %g2 ! g2 = wim
- mov 1, %g4
- sll %g4, %g3, %g4 ! g4 = WIM mask for CW invalid
-
-save_frame_loop:
- sll %g4, 1, %g5 ! rotate the "wim" left 1
- srl %g4, SPARC_NUMBER_OF_REGISTER_WINDOWS - 1, %g4
- or %g4, %g5, %g4 ! g4 = wim if we do one restore
-
- /*
- * If a restore would not underflow, then continue.
- */
-
- andcc %g4, %g2, %g0 ! Any windows to flush?
- bnz done_flushing ! No, then continue
- nop
-
- restore ! back one window
-
- /*
- * Now save the window just as if we overflowed to it.
- */
-
- std %l0, [%sp + CPU_STACK_FRAME_L0_OFFSET]
- std %l2, [%sp + CPU_STACK_FRAME_L2_OFFSET]
- std %l4, [%sp + CPU_STACK_FRAME_L4_OFFSET]
- std %l6, [%sp + CPU_STACK_FRAME_L6_OFFSET]
-
- std %i0, [%sp + CPU_STACK_FRAME_I0_OFFSET]
- std %i2, [%sp + CPU_STACK_FRAME_I2_OFFSET]
- std %i4, [%sp + CPU_STACK_FRAME_I4_OFFSET]
- std %i6, [%sp + CPU_STACK_FRAME_I6_FP_OFFSET]
-
- ba save_frame_loop
- nop
-
-done_flushing:
-
- add %g3, 1, %g3 ! calculate desired WIM
- and %g3, SPARC_NUMBER_OF_REGISTER_WINDOWS - 1, %g3
- mov 1, %g4
- sll %g4, %g3, %g4 ! g4 = new WIM
- mov %g4, %wim
-
- or %g1, SPARC_PSR_ET_MASK, %g1
- mov %g1, %psr ! **** ENABLE TRAPS ****
- ! and restore CWP
- nop
- nop
- nop
-
- ! skip g0
- ld [%o1 + G1_OFFSET], %g1 ! restore the global registers
- ldd [%o1 + G2_OFFSET], %g2
- ldd [%o1 + G4_OFFSET], %g4
- ldd [%o1 + G6_OFFSET], %g6
-
- ldd [%o1 + L0_OFFSET], %l0 ! restore the local registers
- ldd [%o1 + L2_OFFSET], %l2
- ldd [%o1 + L4_OFFSET], %l4
- ldd [%o1 + L6_OFFSET], %l6
-
- ldd [%o1 + I0_OFFSET], %i0 ! restore the output registers
- ldd [%o1 + I2_OFFSET], %i2
- ldd [%o1 + I4_OFFSET], %i4
- ldd [%o1 + I6_FP_OFFSET], %i6
-
- ldd [%o1 + O2_OFFSET], %o2 ! restore the output registers
- ldd [%o1 + O4_OFFSET], %o4
- ldd [%o1 + O6_SP_OFFSET], %o6
- ! do o0/o1 last to avoid destroying heir context pointer
- ldd [%o1 + O0_OFFSET], %o0 ! overwrite heir pointer
-
- jmp %o7 + 8 ! return
- nop ! delay slot
-
-/*
- * void _CPU_Context_restore(
- * Context_Control *new_context
- * )
- *
- * This routine is generally used only to perform restart self.
- *
- * NOTE: It is unnecessary to reload some registers.
- */
-
- .align 4
- PUBLIC(_CPU_Context_restore)
-SYM(_CPU_Context_restore):
- save %sp, -CPU_MINIMUM_STACK_FRAME_SIZE, %sp
- rd %psr, %o2
- ba SYM(_CPU_Context_restore_heir)
- mov %i0, %o1 ! in the delay slot
-
-/*
- * void _ISR_Handler()
- *
- * This routine provides the RTEMS interrupt management.
- *
- * We enter this handler from the 4 instructions in the trap table with
- * the following registers assumed to be set as shown:
- *
- * l0 = PSR
- * l1 = PC
- * l2 = nPC
- * l3 = trap type
- *
- * NOTE: By an executive defined convention, trap type is between 0 and 255 if
- * it is an asynchonous trap and 256 and 511 if it is synchronous.
- */
-
- .align 4
- PUBLIC(_ISR_Handler)
-SYM(_ISR_Handler):
- /*
- * Fix the return address for synchronous traps.
- */
-
- andcc %l3, SPARC_SYNCHRONOUS_TRAP_BIT_MASK, %g0
- ! Is this a synchronous trap?
- be,a win_ovflow ! No, then skip the adjustment
- nop ! DELAY
- mov %l2, %l1 ! do not return to the instruction
- add %l2, 4, %l2 ! indicated
-
-win_ovflow:
- /*
- * Save the globals this block uses.
- *
- * These registers are not restored from the locals. Their contents
- * are saved directly from the locals into the ISF below.
- */
-
- mov %g4, %l4 ! save the globals this block uses
- mov %g5, %l5
-
- /*
- * When at a "window overflow" trap, (wim == (1 << cwp)).
- * If we get here like that, then process a window overflow.
- */
-
- rd %wim, %g4
- srl %g4, %l0, %g5 ! g5 = win >> cwp ; shift count and CWP
- ! are LS 5 bits ; how convenient :)
- cmp %g5, 1 ! Is this an invalid window?
- bne dont_do_the_window ! No, then skip all this stuff
- ! we are using the delay slot
-
- /*
- * The following is same as a 1 position right rotate of WIM
- */
-
- srl %g4, 1, %g5 ! g5 = WIM >> 1
- sll %g4, SPARC_NUMBER_OF_REGISTER_WINDOWS-1 , %g4
- ! g4 = WIM << (Number Windows - 1)
- or %g4, %g5, %g4 ! g4 = (WIM >> 1) |
- ! (WIM << (Number Windows - 1))
-
- /*
- * At this point:
- *
- * g4 = the new WIM
- * g5 is free
- */
-
- /*
- * Since we are tinkering with the register windows, we need to
- * make sure that all the required information is in global registers.
- */
-
- save ! Save into the window
- wr %g4, 0, %wim ! WIM = new WIM
- nop ! delay slots
- nop
- nop
-
- /*
- * Now save the window just as if we overflowed to it.
- */
-
- std %l0, [%sp + CPU_STACK_FRAME_L0_OFFSET]
- std %l2, [%sp + CPU_STACK_FRAME_L2_OFFSET]
- std %l4, [%sp + CPU_STACK_FRAME_L4_OFFSET]
- std %l6, [%sp + CPU_STACK_FRAME_L6_OFFSET]
-
- std %i0, [%sp + CPU_STACK_FRAME_I0_OFFSET]
- std %i2, [%sp + CPU_STACK_FRAME_I2_OFFSET]
- std %i4, [%sp + CPU_STACK_FRAME_I4_OFFSET]
- std %i6, [%sp + CPU_STACK_FRAME_I6_FP_OFFSET]
-
- restore
- nop
-
-dont_do_the_window:
- /*
- * Global registers %g4 and %g5 are saved directly from %l4 and
- * %l5 directly into the ISF below.
- */
-
-save_isf:
-
- /*
- * Save the state of the interrupted task -- especially the global
- * registers -- in the Interrupt Stack Frame. Note that the ISF
- * includes a regular minimum stack frame which will be used if
- * needed by register window overflow and underflow handlers.
- *
- * REGISTERS SAME AS AT _ISR_Handler
- */
-
- sub %fp, CONTEXT_CONTROL_INTERRUPT_FRAME_SIZE, %sp
- ! make space for ISF
-
- std %l0, [%sp + ISF_PSR_OFFSET] ! save psr, PC
- st %l2, [%sp + ISF_NPC_OFFSET] ! save nPC
- st %g1, [%sp + ISF_G1_OFFSET] ! save g1
- std %g2, [%sp + ISF_G2_OFFSET] ! save g2, g3
- std %l4, [%sp + ISF_G4_OFFSET] ! save g4, g5 -- see above
- std %g6, [%sp + ISF_G6_OFFSET] ! save g6, g7
-
- std %i0, [%sp + ISF_I0_OFFSET] ! save i0, i1
- std %i2, [%sp + ISF_I2_OFFSET] ! save i2, i3
- std %i4, [%sp + ISF_I4_OFFSET] ! save i4, i5
- std %i6, [%sp + ISF_I6_FP_OFFSET] ! save i6/fp, i7
-
- rd %y, %g1
- st %g1, [%sp + ISF_Y_OFFSET] ! save y
-
- mov %sp, %o1 ! 2nd arg to ISR Handler
-
- /*
- * Increment ISR nest level and Thread dispatch disable level.
- *
- * Register usage for this section:
- *
- * l4 = _Thread_Dispatch_disable_level pointer
- * l5 = _ISR_Nest_level pointer
- * l6 = _Thread_Dispatch_disable_level value
- * l7 = _ISR_Nest_level value
- *
- * NOTE: It is assumed that l4 - l7 will be preserved until the ISR
- * nest and thread dispatch disable levels are unnested.
- */
-
- sethi %hi(SYM(_Thread_Dispatch_disable_level)), %l4
- ld [%l4 + %lo(SYM(_Thread_Dispatch_disable_level))], %l6
- sethi %hi(SYM(_ISR_Nest_level)), %l5
- ld [%l5 + %lo(SYM(_ISR_Nest_level))], %l7
-
- add %l6, 1, %l6
- st %l6, [%l4 + %lo(SYM(_Thread_Dispatch_disable_level))]
-
- add %l7, 1, %l7
- st %l7, [%l5 + %lo(SYM(_ISR_Nest_level))]
-
- /*
- * If ISR nest level was zero (now 1), then switch stack.
- */
-
- mov %sp, %fp
- subcc %l7, 1, %l7 ! outermost interrupt handler?
- bnz dont_switch_stacks ! No, then do not switch stacks
-
- sethi %hi(SYM(_CPU_Interrupt_stack_high)), %g4
- ld [%g4 + %lo(SYM(_CPU_Interrupt_stack_high))], %sp
-
-dont_switch_stacks:
- /*
- * Make sure we have a place on the stack for the window overflow
- * trap handler to write into. At this point it is safe to
- * enable traps again.
- */
-
- sub %sp, CPU_MINIMUM_STACK_FRAME_SIZE, %sp
-
- wr %l0, SPARC_PSR_ET_MASK, %psr ! **** ENABLE TRAPS ****
-
- /*
- * Vector to user's handler.
- *
- * NOTE: TBR may no longer have vector number in it since
- * we just enabled traps. It is definitely in l3.
- */
-
- sethi %hi(SYM(_ISR_Vector_table)), %g4
- or %g4, %lo(SYM(_ISR_Vector_table)), %g4
- and %l3, 0xFF, %g5 ! remove synchronous trap indicator
- sll %g5, 2, %g5 ! g5 = offset into table
- ld [%g4 + %g5], %g4 ! g4 = _ISR_Vector_table[ vector ]
-
-
- ! o1 = 2nd arg = address of the ISF
- ! WAS LOADED WHEN ISF WAS SAVED!!!
- mov %l3, %o0 ! o0 = 1st arg = vector number
- call %g4, 0
- nop ! delay slot
-
- /*
- * Redisable traps so we can finish up the interrupt processing.
- * This is a VERY conservative place to do this.
- *
- * NOTE: %l0 has the PSR which was in place when we took the trap.
- */
-
- mov %l0, %psr ! **** DISABLE TRAPS ****
-
- /*
- * Decrement ISR nest level and Thread dispatch disable level.
- *
- * Register usage for this section:
- *
- * l4 = _Thread_Dispatch_disable_level pointer
- * l5 = _ISR_Nest_level pointer
- * l6 = _Thread_Dispatch_disable_level value
- * l7 = _ISR_Nest_level value
- */
-
- sub %l6, 1, %l6
- st %l6, [%l4 + %lo(SYM(_Thread_Dispatch_disable_level))]
-
- st %l7, [%l5 + %lo(SYM(_ISR_Nest_level))]
-
- /*
- * If dispatching is disabled (includes nested interrupt case),
- * then do a "simple" exit.
- */
-
- orcc %l6, %g0, %g0 ! Is dispatching disabled?
- bnz simple_return ! Yes, then do a "simple" exit
- nop ! delay slot
-
- /*
- * If a context switch is necessary, then do fudge stack to
- * return to the interrupt dispatcher.
- */
-
- sethi %hi(SYM(_Context_Switch_necessary)), %l4
- ld [%l4 + %lo(SYM(_Context_Switch_necessary))], %l5
-
- orcc %l5, %g0, %g0 ! Is thread switch necessary?
- bnz SYM(_ISR_Dispatch) ! yes, then invoke the dispatcher
- nop ! delay slot
-
- /*
- * Finally, check to see if signals were sent to the currently
- * executing task. If so, we need to invoke the interrupt dispatcher.
- */
-
- sethi %hi(SYM(_ISR_Signals_to_thread_executing)), %l6
- ld [%l6 + %lo(SYM(_ISR_Signals_to_thread_executing))], %l7
-
- orcc %l7, %g0, %g0 ! Were signals sent to the currently
- ! executing thread?
- bz simple_return ! yes, then invoke the dispatcher
- nop ! delay slot
-
- /*
- * Invoke interrupt dispatcher.
- */
-
- PUBLIC(_ISR_Dispatch)
-SYM(_ISR_Dispatch):
-
- /*
- * The following subtract should get us back on the interrupted
- * tasks stack and add enough room to invoke the dispatcher.
- * When we enable traps, we are mostly back in the context
- * of the task and subsequent interrupts can operate normally.
- */
-
- sub %fp, CPU_MINIMUM_STACK_FRAME_SIZE, %sp
-
- or %l0, SPARC_PSR_ET_MASK, %l7 ! l7 = PSR with ET=1
- mov %l7, %psr ! **** ENABLE TRAPS ****
- nop
- nop
- nop
-
- call SYM(_Thread_Dispatch), 0
- nop
-
- /*
- * The CWP in place at this point may be different from
- * that which was in effect at the beginning of the ISR if we
- * have been context switched between the beginning of this invocation
- * of _ISR_Handler and this point. Thus the CWP and WIM should
- * not be changed back to their values at ISR entry time. Any
- * changes to the PSR must preserve the CWP.
- */
-
-simple_return:
- ld [%fp + ISF_Y_OFFSET], %l5 ! restore y
- wr %l5, 0, %y
-
- ldd [%fp + ISF_PSR_OFFSET], %l0 ! restore psr, PC
- ld [%fp + ISF_NPC_OFFSET], %l2 ! restore nPC
- rd %psr, %l3
- and %l3, SPARC_PSR_CWP_MASK, %l3 ! want "current" CWP
- andn %l0, SPARC_PSR_CWP_MASK, %l0 ! want rest from task
- or %l3, %l0, %l0 ! install it later...
- andn %l0, SPARC_PSR_ET_MASK, %l0
-
- /*
- * Restore tasks global and out registers
- */
-
- mov %fp, %g1
-
- ! g1 is restored later
- ldd [%fp + ISF_G2_OFFSET], %g2 ! restore g2, g3
- ldd [%fp + ISF_G4_OFFSET], %g4 ! restore g4, g5
- ldd [%fp + ISF_G6_OFFSET], %g6 ! restore g6, g7
-
- ldd [%fp + ISF_I0_OFFSET], %i0 ! restore i0, i1
- ldd [%fp + ISF_I2_OFFSET], %i2 ! restore i2, i3
- ldd [%fp + ISF_I4_OFFSET], %i4 ! restore i4, i5
- ldd [%fp + ISF_I6_FP_OFFSET], %i6 ! restore i6/fp, i7
-
- /*
- * Registers:
- *
- * ALL global registers EXCEPT G1 and the input registers have
- * already been restored and thuse off limits.
- *
- * The following is the contents of the local registers:
- *
- * l0 = original psr
- * l1 = return address (i.e. PC)
- * l2 = nPC
- * l3 = CWP
- */
-
- /*
- * if (CWP + 1) is an invalid window then we need to reload it.
- *
- * WARNING: Traps should now be disabled
- */
-
- mov %l0, %psr ! **** DISABLE TRAPS ****
- nop
- nop
- nop
- rd %wim, %l4
- add %l0, 1, %l6 ! l6 = cwp + 1
- and %l6, SPARC_PSR_CWP_MASK, %l6 ! do the modulo on it
- srl %l4, %l6, %l5 ! l5 = win >> cwp + 1 ; shift count
- ! and CWP are conveniently LS 5 bits
- cmp %l5, 1 ! Is tasks window invalid?
- bne good_task_window
-
- /*
- * The following code is the same as a 1 position left rotate of WIM.
- */
-
- sll %l4, 1, %l5 ! l5 = WIM << 1
- srl %l4, SPARC_NUMBER_OF_REGISTER_WINDOWS-1 , %l4
- ! l4 = WIM >> (Number Windows - 1)
- or %l4, %l5, %l4 ! l4 = (WIM << 1) |
- ! (WIM >> (Number Windows - 1))
-
- /*
- * Now restore the window just as if we underflowed to it.
- */
-
- wr %l4, 0, %wim ! WIM = new WIM
- restore ! now into the tasks window
-
- ldd [%g1 + CPU_STACK_FRAME_L0_OFFSET], %l0
- ldd [%g1 + CPU_STACK_FRAME_L2_OFFSET], %l2
- ldd [%g1 + CPU_STACK_FRAME_L4_OFFSET], %l4
- ldd [%g1 + CPU_STACK_FRAME_L6_OFFSET], %l6
- ldd [%g1 + CPU_STACK_FRAME_I0_OFFSET], %i0
- ldd [%g1 + CPU_STACK_FRAME_I2_OFFSET], %i2
- ldd [%g1 + CPU_STACK_FRAME_I4_OFFSET], %i4
- ldd [%g1 + CPU_STACK_FRAME_I6_FP_OFFSET], %i6
- ! reload of sp clobbers ISF
- save ! Back to ISR dispatch window
-
-good_task_window:
-
- mov %l0, %psr ! **** DISABLE TRAPS ****
- ! and restore condition codes.
- ld [%g1 + ISF_G1_OFFSET], %g1 ! restore g1
- jmp %l1 ! transfer control and
- rett %l2 ! go back to tasks window
-
-/* end of file */