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SPAbs() FLOAT SPAbs( FLOAT parm );
Take absolute value of FFP variable.
SPAdd() FLOAT SPAdd( FLOAT leftParm, FLOAT rightParm);
Add two FFP variables.
SPCeil() FLOAT SPCeil( FLOAT parm );
Computer largest integer less than or equal to variable.
SPCmp() LONG SPCmp( FLOAT leftParm, FLOAT rightParm);
Compare two FFP variables.
SPDiv() FLOAT SPDiv( FLOAT leftParm, FLOAT rightParm);
Divide two FFP variables.
SPFix() LONG SPFix( FLOAT parm );
Convert FFP variable to integer.
SPFloor() FLOAT SPFloor( FLOAT parm );
Compute least integer greater than or equal to variable.
SPFlt() FLOAT SPFlt( long integer );
Convert integer variable to FFP.
SPMul() FLOAT SPMul( FLOAT leftParm, FLOAT rightParm);
Multiply two FFP variables.
SPNeg() FLOAT SPNeg( FLOAT parm );
Take two's complement of FFP variable.
SPSub() FLOAT SPSub( FLOAT leftParm, FLOAT rightParm);
Subtract two FFP variables.
SPTst() LONG SPTst( FLOAT parm );
Test an FFP variable against zero.
Be sure to include the proper data type definitions shown below.
#include <exec/types.h>
#include <libraries/mathffp.h>
#include <clib/mathffp_protos.h>
struct Library *MathBase;
VOID main()
{
FLOAT f1, f2, f3;
LONG i1;
if (MathBase = OpenLibrary("mathffp.library", 0))
{
i1 = SPFix(f1); /* Call SPFix entry */
f1 = SPFlt(i1); /* Call SPFlt entry */
if (SPCmp(f1,f2)) {}; /* Call SPCmp entry */
if (!(SPTst(f1))) {}; /* Call SPTst entry */
f1 = SPAbs(f2); /* Call SPAbs entry */
f1 = SPNeg(f2); /* Call SPNeg entry */
f1 = SPAdd(f2, f3); /* Call SPAdd entry */
f1 = SPSub(f2, f3); /* Call SPSub entry */
f1 = SPMul(f2, f3); /* Call SPMul entry */
f1 = SPDiv(f2, f3); /* Call SPDiv entry */
f1 = SPCeil(f2); /* Call SPCeil entry */
f1 = SPFloor(f2); /* Call SPFloor entry */
CloseLibrary(MathBase);
}
else
printf("Can't open mathffp.library\n");
}
The assembly language interface to the FFP basic math routines is shown
below, including some details about how the system flags are affected by
each operation. The access mechanism is:
MOVEA.L _MathBase,A6
JSR _LVOSPFix(A6)
__________________________________________________________________
| |
| FFP Basic Assembly Functions |
| |
| Function Input Output Condition Codes |
|__________________________________________________________________|
| | | | |
| _LVOSPAbs | D0=FFP arg | D0=FFP absolute | N=0 |
| | | value | Z=1 if result |
| | | | is zero |
| | | | V=0 |
| | | | C=undefined |
| | | | X=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPAdd | D1=FFP arg1 | D0=FFP addition | N=1 if result |
| | D0=FFP arg2 | of arg1 + arg2 | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=1 if result |
| | | | overflowed |
| | | | C=undefined |
| | | | Z=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPCeil | D0=FFP arg | D0=least integer | N=1 if result |
| | | >=arg | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=undefined |
| | | | C=undefined |
| | | | Z=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPCmp | D1=FFP arg1 | D0=+1 if arg1>arg2 | N=0 |
| | D0=FFP arg2 | D0=-1 if arg1<arg2 | Z=1 if result |
| | | D0=0 if arg1=arg2 | is zero |
| | | | V=0 |
| | | | C=undefined |
| | | | X=undefined |
| | | | GT=arg2>arg1 |
| | | | GE=arg2>=arg1 |
| | | | EQ=arg2=arg1 |
| | | | NE=arg2<>arg1 |
| | | | LT=arg2<arg1 |
| | | | LE=arg2<=arg1 |
|-------------|-------------|--------------------|-----------------|
| _LVOSPDiv | D1=FFP arg1 | D0=FFP division | N=1 if result |
| | D0=FFP arg2 | of arg2/arg1 | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=1 if result |
| | | | overflowed |
| | | | C=undefined |
| | | | Z=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPFix | D0=FFP arg | D0=Integer | N=1 if result |
| | | (two's complement) | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=1 if overflow |
| | | | occurred |
| | | | C=undefined |
| | | | X=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPFloor | D0=FFP arg | D0=largest integer | N=1 if result |
| | | <= arg | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=undefined |
| | | | C=undefined |
| | | | Z=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPFlt | D0=Integer | D0=FFP result | N=1 if result |
| | (two's | | is negative |
| | complement) | | Z=1 if result |
| | | | is zero |
| | | | V=0 |
| | | | C=undefined |
| | | | X=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPMul | D0=FFP arg1 | D0=FFP | N=1 if result |
| | D1=FFP arg2 | multiplication | is negative |
| | | of arg1*arg2 | Z=1 if result |
| | | | is zero |
| | | | V=1 if result |
| | | | overflowed |
| | | | C=undefined |
| | | | Z=undefined |
| | | | |
|-------------|-------------|--------------------|-----------------|
| _LVOSPNeg | D0=FFP arg | D0=FFP negated | N=1 if result |
| | | | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=0 |
| | | | C=undefined |
| | | | X=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPSub | D1=FFP arg1 | D0=FFP subtraction | N=1 if result |
| | D0=FFP arg2 | of arg2-arg1 | is negative |
| | | | Z=1 if result |
| | | | is zero |
| | | | V=1 if result |
| | | | overflowed |
| | | | C=undefined |
| | | | Z=undefined |
|-------------|-------------|--------------------|-----------------|
| _LVOSPTst | D1=FFP arg | D0=+1 if arg>0.0 | N=1 if result |
| | | D0=-1 if arg<0.0 | is negative |
| | | D0=0 if arg=0.0 | Z=1 if result |
| | | | is zero |
| | | | V=0 |
| | | | C=undefined |
| | | | X=undefined |
| | Note: This | | EQ=arg=0.0 |
| | routine | | NE=arg<>0.0 |
| | trashes the | | PL=arg>=0.0 |
| | arg in D1. | | MI=arg<0.0 |
|_____________|_____________|____________________|_________________|