Floating Point Conversion

Name:

FLOT $X,$Z	FLOT $X,Z
FLOTU $X,$Z	FLOTU $X,Z
FIX $X,$Z	FIXU $X,$Z

Specification:

FLOT: f($X) ← s($Z)
FLOTU: f($X) ← u($Z)
FIX: s($X) ← int(f($Z))
FIXU: u($X) ← (int(f($Z)))mod2⁶⁴

Timing:

4υ

Description:

Converts numbers from integer representation to floating point representation and vice versa. An optional Y-Operand can be used to specify one of the following rounding modes: ROUND_OFF, ROUND_UP, ROUND_DOWN, or ROUND_NEAR.

FLOT: "convert fixed to floating". The integer in $Z or the immediate constant Z is converted to the nearest floating point value (using the current rounding mode) and placed in register $X. A floating inexact exception occurs if rounding is necessary.

FLOTU: "convert fixed to floating unsigned". FLOTU is like FLOT, but $Z is treated as an unsigned integer.

FIX: "convert floating to fixed". The floating point number in register $Z is converted to an integer as with the FINT instruction, and the resulting integer (mod 2⁶⁴) is placed in register $X. An invalid exception occurs if $Z is infinite or a NaN; in that case $X is simply set equal to $Z. A float-to-fix exception occurs if the result is less than −2⁶⁴ or greater than 2⁶⁴ - 1.

FIXU: "convert floating to fixed unsigned". This instruction is identical to FIX except that no float-to-fix exception occurs.

FLOT:	f($X)	← s($Z)
FLOTU:	f($X)	← u($Z)
FIX:	s($X)	← int(f($Z))
FIXU:	u($X)	← (int(f($Z)))mod2⁶⁴

FLOT:	"convert fixed to floating". The integer in $Z or the immediate constant Z is converted to the nearest floating point value (using the current rounding mode) and placed in register $X. A floating inexact exception occurs if rounding is necessary.
FLOTU:	"convert fixed to floating unsigned". FLOTU is like FLOT, but $Z is treated as an unsigned integer.
FIX:	"convert floating to fixed". The floating point number in register $Z is converted to an integer as with the FINT instruction, and the resulting integer (mod 2⁶⁴) is placed in register $X. An invalid exception occurs if $Z is infinite or a NaN; in that case $X is simply set equal to $Z. A float-to-fix exception occurs if the result is less than −2⁶⁴ or greater than 2⁶⁴ - 1.
FIXU:	"convert floating to fixed unsigned". This instruction is identical to FIX except that no float-to-fix exception occurs.