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#
# Setjmp/longjmp for MeP
#
# DJ Delorie, Red Hat Inc.
#
# 19 32-bit words in the jmpbuf:
# $0
# $1
# ...
# $15
# $pc
# $hi
# $lo
#
# Note that $0 is saved but not restored. It can't be restored
# as it's the return value of setjmp, but we save it in case
# some application wants to see it in the jmp_buf. Ideally,
# we should not need to save anything that is call-clobbered,
# but you never know what the user is going to tell gcc with -f
# options.
.noregerr
.text
.globl setjmp
.type setjmp,@function
setjmp:
# $1 is the address of the buffer. We return 0 in $0.
sw $0, ($1)
sw $1, 4($1)
sw $2, 8($1)
sw $3, 12($1)
sw $4, 16($1)
sw $5, 20($1)
sw $6, 24($1)
sw $7, 28($1)
sw $8, 32($1)
sw $9, 36($1)
sw $10, 40($1)
sw $11, 44($1)
sw $12, 48($1)
sw $13, 52($1)
sw $14, 56($1)
sw $15, 60($1)
ldc $0, $lp
sw $0, 64($1)
ldc $0, $opt
sra $0, 24
and3 $0, $0, 3
beqz $0, sj_skip_hilo
ldc $0, $hi
sw $0, 68($1)
ldc $0, $lo
sw $0, 72($1)
sj_skip_hilo:
mov $0, 0
ret
.globl longjmp
.type longjmp,@function
longjmp:
# $1 is the address of the buffer. $2 is the value setjmp
# returns. We do not faithfully restore $0 or $lp, because
# the act of calling setjmp clobbered those anyway.
bnez $2, rv_not_zero
mov $2, 1
rv_not_zero:
# We restore $sp first so we can save the return value there,
# otherwise we'd need to have another unrestored register.
lw $15, 60($1)
add3 $sp, $sp, -4
sw $2, ($sp)
# Now restore the general registers.
lw $2, 8($1)
lw $3, 12($1)
lw $4, 16($1)
lw $5, 20($1)
lw $6, 24($1)
lw $7, 28($1)
lw $8, 32($1)
lw $9, 36($1)
lw $10, 40($1)
lw $11, 44($1)
lw $12, 48($1)
lw $13, 52($1)
lw $14, 56($1)
# We restore $pc's value to $lp so that we can just ret later.
lw $0, 64($1)
stc $0, $lp
ldc $0, $opt
sra $0, 24
and3 $0, $0, 3
beqz $0, lj_skip_hilo
lw $0, 68($1)
stc $0, $hi
lw $0, 72($1)
stc $0, $lo
lj_skip_hilo:
# Restore $1
lw $1, 8($1)
# Get the return value off the stack, and restore the stack.
lw $0, ($sp)
add3 $sp, $sp, 4
ret
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