MSC100ABIRM Motorola / Freescale Semiconductor, MSC100ABIRM Datasheet - Page 30

• Manufacturer Part Number: MSC100ABIRM
• Description: SC100 Application Binary Interface Reference Manual
• Manufacturer: Motorola / Freescale Semiconductor

High-Level Languages Issues
To ensure the ability to link code produced by different compilers into a single executable, it is required
that names of compiler support library functions match those listed in Table 3-3 and Table 3-4.
Routines in support libraries must satisfy the following constraints:
These properties permit a compiler to make assumptions about variable lifetimes across library function
calls: values in memory will not change, previously dereferenced pointers need not be referenced again.
3.5.2 Floating-Point Routines
These routines should comply with the stack-based calling conventions.
The data formats are as specified in IEEE-754. The math routines are not required to compute results as
specified in IEEE-754. Implementation of these routines must document the degree to which operations
conform to the IEEE standard. Not all users of floating point require IEEE-754 precision and exception
handling, and may not want to incur the overhead that complete conformance requires.
SpFloat is used in Table 3-3 and Table 3-4 to represent a 32-bit basic type.
3-4
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SpFloat _f_add( SpFloat a, SpFloat b );
SpFloat
SpFloat _f_mul( SpFloat a, SpFloat b)
SpFloat _f_div ( SpFloat a, SpFloat b)
void
void _f_fge ( SpFloat a, SpFloat b)
void _f_fgt ( SpFloat a, SpFloat b)
SpFloat _f_itof( long a)
SpFloat _f_utof( unsigned long a)
long
unsigned long _f_ftou( SpFloat a)
The only external state information used is floating-point operation mode (rounding mode, flush to
zero, etc.).
No other global state can be modified.
Identical results must be returned when a routine is reinvoked with the same input arguments.
Multiple calls with the same input arguments can be collapsed into a single call with a cached result.
_f_feq
_f_ftoi( SpFloat a)
_f_sub
( SpFloat a, SpFloat b)
( SpFloat a, SpFloat b)
Function Prototype
Table 3-3. Floating-Point Routines
Preliminary (April 2000)
Returns the value of a+b
Returns the value of a-b.
Returns the value of a*b.
Returns the value of a/b.
Sets the T bit in the status register if a=b.
Sets the T bit in the status register if a>=b.
Sets the T bit in the status register if a>b.
Converts a 32-bit signed integer value to
floating-point representation.
Converts a 32-bit unsigned integer value to
floating-point representation.
Converts a floating-point value to a 32-bit signed
integer representation.
Converts a floating-point value to a 32-bit unsigned
integer representation.
Description
SC100 Application Binary Interface