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#*********************************************************************
#* *
#* Objective Caml *
#* *
#* Xavier Leroy, projet Cristal, INRIA Rocquencourt *
#* *
#* Copyright 1996 Institut National de Recherche en Informatique et *
#* Automatique. Distributed only by permission. *
#* *
#*********************************************************************
# $Id$
.csect .text[PR]
#### Invoke the garbage collector. r0 contains the return address
.globl .caml_call_gc
.caml_call_gc:
# Set up stack frame
stwu 1, -0x1C0(1)
# 0x1C0 = 4*32 (int regs) + 8*32 (float regs) + 64 (space for C call)
# Record last return address into Caml code
lwz 11, L..caml_last_return_address(2)
stw 0, 0(11)
# Record return address into call_gc stub code
mflr 0
stw 0, 0x1C0+8(1)
# Record lowest stack address
lwz 11, L..caml_bottom_of_stack(2)
addi 0, 1, 0x1C0
stw 0, 0(11)
# Record pointer to register array
lwz 11, L..caml_gc_regs(2)
addi 0, 1, 8*32 + 64
stw 0, 0(11)
# Save current allocation pointer for debugging purposes
lwz 11, L..young_ptr(2)
stw 31, 0(11)
# Save exception pointer (if e.g. a sighandler raises)
lwz 11, L..caml_exception_pointer(2)
stw 29, 0(11)
# Save all registers used by the code generator
addi 11, 1, 8*32 + 64 - 4
stwu 3, 4(11)
stwu 4, 4(11)
stwu 5, 4(11)
stwu 6, 4(11)
stwu 7, 4(11)
stwu 8, 4(11)
stwu 9, 4(11)
stwu 10, 4(11)
stwu 14, 4(11)
stwu 15, 4(11)
stwu 16, 4(11)
stwu 17, 4(11)
stwu 18, 4(11)
stwu 19, 4(11)
stwu 20, 4(11)
stwu 21, 4(11)
stwu 22, 4(11)
stwu 23, 4(11)
stwu 24, 4(11)
stwu 25, 4(11)
stwu 26, 4(11)
stwu 27, 4(11)
stwu 28, 4(11)
addi 11, 1, 64 - 8
stfdu 1, 8(11)
stfdu 2, 8(11)
stfdu 3, 8(11)
stfdu 4, 8(11)
stfdu 5, 8(11)
stfdu 6, 8(11)
stfdu 7, 8(11)
stfdu 8, 8(11)
stfdu 9, 8(11)
stfdu 10, 8(11)
stfdu 11, 8(11)
stfdu 12, 8(11)
stfdu 13, 8(11)
stfdu 14, 8(11)
stfdu 15, 8(11)
stfdu 16, 8(11)
stfdu 17, 8(11)
stfdu 18, 8(11)
stfdu 19, 8(11)
stfdu 20, 8(11)
stfdu 21, 8(11)
stfdu 22, 8(11)
stfdu 23, 8(11)
stfdu 24, 8(11)
stfdu 25, 8(11)
stfdu 26, 8(11)
stfdu 27, 8(11)
stfdu 28, 8(11)
stfdu 29, 8(11)
stfdu 30, 8(11)
stfdu 31, 8(11)
# Call the GC
bl .garbage_collection
or 0, 0, 0
# Reload new allocation pointer and allocation limit
lwz 11, L..young_ptr(2)
lwz 31, 0(11)
lwz 11, L..young_limit(2)
lwz 30, 0(11)
# Restore all regs used by the code generator
addi 11, 1, 8*32 + 64 - 4
lwzu 3, 4(11)
lwzu 4, 4(11)
lwzu 5, 4(11)
lwzu 6, 4(11)
lwzu 7, 4(11)
lwzu 8, 4(11)
lwzu 9, 4(11)
lwzu 10, 4(11)
lwzu 14, 4(11)
lwzu 15, 4(11)
lwzu 16, 4(11)
lwzu 17, 4(11)
lwzu 18, 4(11)
lwzu 19, 4(11)
lwzu 20, 4(11)
lwzu 21, 4(11)
lwzu 22, 4(11)
lwzu 23, 4(11)
lwzu 24, 4(11)
lwzu 25, 4(11)
lwzu 26, 4(11)
lwzu 27, 4(11)
lwzu 28, 4(11)
addi 11, 1, 64 - 8
lfdu 1, 8(11)
lfdu 2, 8(11)
lfdu 3, 8(11)
lfdu 4, 8(11)
lfdu 5, 8(11)
lfdu 6, 8(11)
lfdu 7, 8(11)
lfdu 8, 8(11)
lfdu 9, 8(11)
lfdu 10, 8(11)
lfdu 11, 8(11)
lfdu 12, 8(11)
lfdu 13, 8(11)
lfdu 14, 8(11)
lfdu 15, 8(11)
lfdu 16, 8(11)
lfdu 17, 8(11)
lfdu 18, 8(11)
lfdu 19, 8(11)
lfdu 20, 8(11)
lfdu 21, 8(11)
lfdu 22, 8(11)
lfdu 23, 8(11)
lfdu 24, 8(11)
lfdu 25, 8(11)
lfdu 26, 8(11)
lfdu 27, 8(11)
lfdu 28, 8(11)
lfdu 29, 8(11)
lfdu 30, 8(11)
lfdu 31, 8(11)
# Return to caller (the stub code), leaving return address into
# Caml code in the link register
lwz 0, 0x1C0+8(1)
mtctr 0
lwz 11, L..caml_last_return_address(2)
lwz 0, 0(11)
addic 0, 0, -16 # Restart the allocation (4 instructions)
mtlr 0
# Say we are back into Caml code
li 12, 0
stw 12, 0(11) # 11 still points to caml_last_return_address
# Deallocate stack frame
addi 1, 1, 0x1C0
# Return
bctr
#### Call a C function from Caml
.globl .caml_c_call
.caml_c_call:
# Save return address in 25
mflr 25
# Record lowest stack address and return address
lwz 27, L..caml_bottom_of_stack(2)
lwz 24, L..caml_last_return_address(2)
stw 1, 0(27)
stw 25, 0(24)
# Make the exception handler and alloc ptr available to the C code
lwz 27, L..young_ptr(2)
lwz 26, L..caml_exception_pointer(2)
stw 31, 0(27)
stw 29, 0(26)
# Preserve RTOC and return address in callee-save registers
# The C function will preserve them, and the Caml code does not
# expect them to be preserved
# Return address is in 25, RTOC is in 26, pointer to young_ptr in 27,
# pointer to caml_last_return_address is in 24
# Call the function (descriptor in 11)
lwz 0, 0(11)
mr 26, 2
mtlr 0
lwz 2, 4(11)
lwz 11, 8(11)
blrl
# Restore return address
mtlr 25
# Restore RTOC
mr 2, 26
# Reload allocation pointer
lwz 31, 0(27) # 27 still points to young_ptr
# Say we are back into Caml code
li 12, 0
stw 12, 0(24) # 24 still points to caml_last_return_address
# Return to caller
blr
#### Raise an exception from C
.globl .raise_caml_exception
.raise_caml_exception:
# Reload Caml global registers
lwz 4, L..caml_exception_pointer(2)
lwz 5, L..young_ptr(2)
lwz 6, L..young_limit(2)
lwz 1, 0(4)
lwz 31, 0(5)
lwz 30, 0(6)
# Say we are back into Caml code
lwz 4, L..caml_last_return_address(2)
li 0, 0
stw 0, 0(4)
# Pop trap frame
lwz 0, 0(1)
lwz 29, 4(1)
mtlr 0
lwz 2, 20(1)
addi 1, 1, 24
# Branch to handler
blr
#### Start the Caml program
.globl .caml_start_program
.caml_start_program:
lwz 11, L..caml_program(2)
#### Code shared between caml_start_program and callback*
L..102:
mflr 0
# Save return address
stw 0, 8(1)
# Save all callee-save registers
stw 13, -76(1)
stw 14, -72(1)
stw 15, -68(1)
stw 16, -64(1)
stw 17, -60(1)
stw 18, -56(1)
stw 19, -52(1)
stw 20, -48(1)
stw 21, -44(1)
stw 22, -40(1)
stw 23, -36(1)
stw 24, -32(1)
stw 25, -28(1)
stw 26, -24(1)
stw 27, -20(1)
stw 28, -16(1)
stw 29, -12(1)
stw 30, -8(1)
stw 31, -4(1)
stfd 14, -224(1)
stfd 15, -216(1)
stfd 16, -208(1)
stfd 17, -200(1)
stfd 18, -192(1)
stfd 19, -184(1)
stfd 20, -176(1)
stfd 21, -168(1)
stfd 22, -160(1)
stfd 23, -152(1)
stfd 24, -144(1)
stfd 25, -136(1)
stfd 26, -128(1)
stfd 27, -120(1)
stfd 28, -112(1)
stfd 29, -104(1)
stfd 30, -96(1)
stfd 31, -88(1)
# Allocate and link stack frame
stwu 1, -280(1)
# Set up a callback link
addi 1, 1, -24
lwz 9, L..caml_bottom_of_stack(2)
lwz 10, L..caml_last_return_address(2)
lwz 12, L..caml_gc_regs(2)
lwz 9, 0(9)
lwz 10, 0(10)
lwz 12, 0(12)
stw 9, 0(1)
stw 10, 4(1)
stw 12, 8(1)
# Build an exception handler to catch exceptions escaping out of Caml
bl L..103
b L..104
L..103:
addi 1, 1, -24
lwz 9, L..caml_exception_pointer(2)
mflr 0
lwz 29, 0(9)
stw 0, 0(1)
stw 29, 4(1)
stw 2, 20(1)
mr 29, 1
# Reload allocation pointers
lwz 9, L..young_ptr(2)
lwz 10, L..young_limit(2)
lwz 31, 0(9)
lwz 30, 0(10)
# Say we are back into Caml code
lwz 9, L..caml_last_return_address(2)
li 0, 0
stw 0, 0(9)
# Call the Caml code
lwz 0, 0(11)
stw 2, 20(1)
mtlr 0
lwz 2, 4(11)
L..105:
blrl
lwz 2, 20(1)
# Pop the trap frame, restoring caml_exception_pointer
lwz 9, 4(1)
lwz 10, L..caml_exception_pointer(2)
addi 1, 1, 24
stw 9, 0(10)
# Pop the callback link, restoring the global variables
L..106:
lwz 7, 0(1)
lwz 8, 4(1)
lwz 9, 8(1)
lwz 10, L..caml_bottom_of_stack(2)
lwz 11, L..caml_last_return_address(2)
lwz 12, L..caml_gc_regs(2)
stw 7, 0(10)
stw 8, 0(11)
stw 9, 0(12)
addi 1, 1, 24
# Update allocation pointer
lwz 11, L..young_ptr(2)
stw 31, 0(11)
# Deallocate stack frame
addi 1, 1, 280
# Restore callee-save registers
lwz 13, -76(1)
lwz 14, -72(1)
lwz 15, -68(1)
lwz 16, -64(1)
lwz 17, -60(1)
lwz 18, -56(1)
lwz 19, -52(1)
lwz 20, -48(1)
lwz 21, -44(1)
lwz 22, -40(1)
lwz 23, -36(1)
lwz 24, -32(1)
lwz 25, -28(1)
lwz 26, -24(1)
lwz 27, -20(1)
lwz 28, -16(1)
lwz 29, -12(1)
lwz 30, -8(1)
lwz 31, -4(1)
lfd 14, -224(1)
lfd 15, -216(1)
lfd 16, -208(1)
lfd 17, -200(1)
lfd 18, -192(1)
lfd 19, -184(1)
lfd 20, -176(1)
lfd 21, -168(1)
lfd 22, -160(1)
lfd 23, -152(1)
lfd 24, -144(1)
lfd 25, -136(1)
lfd 26, -128(1)
lfd 27, -120(1)
lfd 28, -112(1)
lfd 29, -104(1)
lfd 30, -96(1)
lfd 31, -88(1)
# Reload return address
lwz 0, 8(1)
mtlr 0
# Return
blr
# The trap handler:
L..104:
# Update caml_exception_pointer
lwz 9, L..caml_exception_pointer(2)
stw 29, 0(9)
# Encode exception bucket as an exception result and return it
ori 3, 3, 2
b L..106
#### Callback from C to Caml
.globl .callback_exn
.callback_exn:
# Initial shuffling of arguments
mr 0, 3 # Closure
mr 3, 4 # Argument
mr 4, 0
lwz 11, 0(4) # Code pointer
b L..102
.globl .callback2_exn
.callback2_exn:
mr 0, 3 # Closure
mr 3, 4 # First argument
mr 4, 5 # Second argument
mr 5, 0
lwz 11, L..caml_apply2(2)
b L..102
.globl .callback3_exn
.callback3_exn:
mr 0, 3 # Closure
mr 3, 4 # First argument
mr 4, 5 # Second argument
mr 5, 6 # Third argument
mr 6, 0
lwz 11, L..caml_apply3(2)
b L..102
#### Frame table
.csect .data[RW]
.globl system_frametable
system_frametable:
.long 1 # one descriptor
.long L..105 + 4 # return address into callback
.short -1 # negative size count => use callback link
.short 0 # no roots here
#### TOC entries
.toc
L..young_limit:
.tc young_limit[TC], young_limit
L..young_ptr:
.tc young_ptr[TC], young_ptr
L..caml_bottom_of_stack:
.tc caml_bottom_of_stack[TC], caml_bottom_of_stack
L..caml_last_return_address:
.tc caml_last_return_address[TC], caml_last_return_address
L..caml_gc_regs:
.tc caml_gc_regs[TC], caml_gc_regs
L..caml_exception_pointer:
.tc caml_exception_pointer[TC], caml_exception_pointer
L..gc_entry_regs:
.tc gc_entry_regs[TC], gc_entry_regs
L..gc_entry_float_regs:
.tc gc_entry_float_regs[TC], gc_entry_float_regs
L..caml_program:
.tc caml_program[TC], caml_program
L..caml_apply2:
.tc caml_apply2[TC], caml_apply2
L..caml_apply3:
.tc caml_apply3[TC], caml_apply3
#### Function closures
.csect caml_call_gc[DS]
caml_call_gc:
.long .caml_call_gc, TOC[tc0], 0
.globl caml_c_call
.csect caml_c_call[DS]
caml_c_call:
.long .caml_c_call, TOC[tc0], 0
.globl raise_caml_exception
.csect raise_caml_exception[DS]
raise_caml_exception:
.long .raise_caml_exception, TOC[tc0], 0
.globl caml_start_program
.csect caml_start_program[DS]
caml_start_program:
.long .caml_start_program, TOC[tc0], 0
.globl callback_exn
.csect callback_exn[DS]
callback_exn:
.long .callback_exn, TOC[tc0], 0
.globl callback2_exn
.csect callback2_exn[DS]
callback2_exn:
.long .callback2_exn, TOC[tc0], 0
.globl callback3_exn
.csect callback3_exn[DS]
callback3_exn:
.long .callback3_exn, TOC[tc0], 0
|
