kvisc/vm/in/ARITH

# The OS/K Team licenses this file to you under the MIT license.
# See the LICENSE file in the project root for more information.

#---------------------------------------------------------------------------#
# Arithmetic instructions                                                   #
#---------------------------------------------------------------------------#

#
# CMP Comparison instruction
#
#       $1 - $2
#
# Sets CF if unsigned integer overflow occur, clears it otherwise
# Sets OF is signed integer overflow occur, clears it otherwise
# Sets ZF and SF according to the result
#
cmp r ri
cmp m ri

#
# Arithmetical SGN operation
#
#       IF ($1 == 0) THEN
#           $2 = 0
#       ELIF ($1 GT 0) THEN
#           $2 = 1
#       ELSE
#           $2 = LONG_MIN
#       FI
#
# Treats $1 and $2 as signed values
#
# Preserves all flags
#
sgn r r

#
# Arithmetical NEG operation
#
#       $1 = NOT($2) + 1
#
# Preserves all flags
#
neg r r

#
# Arithmetical INC operation
#
#       $1 = $1 + 1
#
# Preserves all flags
#
inc rm

#
# Arithmetical DEC operation
#
#       $1 = $1 - 1
#
# Preserves all flags
#
dec rm

#
# Arithmetical ADD operation
#
#       $dest1 = $src1 + $src2
#
# Sets CF if unsigned integer overflow occur, clears it otherwise
# Sets OF is signed integer overflow occur, clears it otherwise
# Sets ZF and SF according to the result
#
add r rim
add r r ri

add m ri
add m r ri

addf r ri
addf r r ri

#
# Atomic exchange and add (XADD)
#
#       $tmp = $1
#       $1 = $1 + $2
#       $2 = $1
#
# Preserves all flags
#
xadd r rm
xadd m r

#
# Arithmetical SUB operation
#
#       $dest = $src1 - $src2
#
# Sets CF if unsigned integer overflow occur, clears it otherwise
# Sets OF is signed integer overflow occur, clears it otherwise
# Sets ZF and SF according to the result
#
sub r rim
sub r r ri

sub m ri
sub m r ri

subf r ri
subf r r ri


#
# Arithmetical ADD/SUB operation, with carry/overflow
#
#       $dest = $src1 + $src2 + CF      (ADC)
#       $dest = $src1 + $src2 + OF      (ADO)
#       $dest = $src1 - $src2 - CF      (SBB)
#       $dest = $src1 - $src2 - OF      (SBO)
#
# Preserves ZF and SF
# Flags CF and OF are undefined for now
#
adc r r
ado r r
sbb r r
sbo r r

#
# Arithmetical unsigned MUL operation
#
#       $dest = LO($src1 * $src2)
#
# Preserves ZF and SF
# Sets CF and OF if HI($src1 * $src2) > 0, clears them otherwise
#
mul r ri
mul r r ri
mulf r r ri

# Arithmetical unsigned MUL operation
#
#       $dest1 = HI($dest2 * $src)
#       $dest2 = LO($dest2 * $src)
#
# Sets CF and OF if HI($2 * $3) > 0, clears them otherwise
# Preserves ZF and SF
#
mulhi r r ri

#
# Arithmetical unsigned DIV operation
#
#       $dest1 = $1 DIV $2
#
# Preserves all flags
#
div r ri
div r r ri

#
# Arithmetical unsigned modulo operation (REM)
#
#       $1 = $1 MOD $2
#
# Preserves all flags
#
rem r ri
rem r r ri