Floating point number type object

A CTF floating point number type.

See also: Type object.

Properties

Property	Type	Description	Required?	Default value
class	String	Set to flt, float, or floating-point	Required	N/A
size	Floating point number type size object	Size parameters	Required	N/A
align	Integer (positive)	Alignment (bits) (power of two)	Optional	8
byte-order	String	Byte order, amongst: le: little-endian be: big-endian	Optional	Native byte order defined in the Trace object

All the properties which have a default value can also be set to null to force this default value. This is especially useful when also using type inheritance or when including external YAML files.

Example

class: float
size:
  exp: 11
  mant: 53
align: 64
byte-order: be

Generated C type

• 8-bit exponent, 24-bit mantissa, 32-bit alignment: float
• 11-bit exponent, 53-bit mantissa, 64-bit alignment: double
• Other combination: uint64_t

Floating point number type size object

The CTF floating point number type is encoded, in a binary stream, following IEEE 754-2008's interchange format. The required parameters are the exponent and significand sizes, in bits. In CTF, the mantissa size includes the sign bit, whereas IEEE 754-2008's significand size does not include it.

Properties

Property	Type	Description	Required?	Default value
exp	Integer (positive)	Exponent size (bits)	Required	N/A
mant	Integer (positive)	Mantissa size (significand size + 1) (bits)	Required	N/A

As per IEEE 754-2008, the sum of the exp and mant properties must be a multiple of 32.

The sum of the exp and mant properties must be lesser than or equal to 64.

Example

exp: 8
mant: 24