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some updates

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mrdudz 2023-08-31 05:20:25 +02:00
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libsrc/float/readme.md
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@ -72,27 +72,32 @@ Related to fp stuff are:
files are provided for the C64 and VIC20 (fp754kernal.o). The samples will
automatically use the overrides.
### Wanted
### WANTED
- For the time being, i will not look at writing IEEE754 functions in assembly.
Please see below for more info on what is needed to do this, should you be
interested in doing this.
interested in doing this. Please contact me before you are putting work into
this, so we can discuss some things and prevent anyone wasting time.
- It might be possible to produce a similar kernal- or OS- wrapper override file
for other targets (or port the CBM one to other CBM targets).
as the C64 one for other targets (or port the C64 one to other CBM targets).
- If you create a new one, keep in mind that the compiler *right now* will
currently work with IEEE754 floats, which your library calls must also work
with (which will involve converting forth and back to whatever other format
at runtime)
at runtime), and there is no easy way tp change that.
- Similar to the softfloat library, it would be nice to have a reference
implementation for the math stuff as well.
- Also the math stuff should be implemented in assembly at some point :)
### Roadmap
- Test/Fix using the Softfloat lib some more
- Find some generic math functions that we can use
- When all obvious tests have been created and work OK, we can merge
After the merge, the following things can be done more or less independent from
each other (not necessarily by me :)):
- implement ieee754 library
- implement IEEE754 library
- for generic support this will be the best compromise for standard compliance
and speed, but will take more RAM than alternatives.
- Once implemented, it will work for all targets.
@ -309,7 +314,7 @@ feaxlong Primary float -> 32bit long - * - -
ftosaddeax Primary = TOS + Primary * * ? ? g_add
ftossubeax Primary = TOS - Primary * * ? ? g_sub
ftosrsubeax Primary = Primary - TOS - - - - g_rsub
ftosrsubeax Primary = Primary - TOS * * - - g_rsub
ftosmuleax Primary = TOS * Primary * * ? - g_mul
ftosdiveax Primary = TOS / Primary * * ? - g_div
@ -323,15 +328,6 @@ ftoslteax Test for less than * * - -
ftosneeax Test for not equal * * - - g_ne
ftoseqeax Test for equal * * - - g_eq
```
### extra functions
optional utility functions.
```
func description softfloat cbmfp wozfp 754
char *_ftostr(char *d, float s) * * ? ? for printf family
float _strtof(char *d) - * - - for scanf family
```
### math.h functions
these are optional, required for standard libm
@ -351,6 +347,17 @@ float fabsf(float x) - * - -
float roundf(float x) - * - -
float truncf(float x) - * - -
```
### extra functions
optional utility functions.
```
func description softfloat cbmfp wozfp 754
char *_ftostr(char *d, float s) * * ? ? for printf family
float _strtof(char *d) - * - - for scanf family
```
--------------------------------------------------------------------------------
- https://www.geeksforgeeks.org/ieee-standard-754-floating-point-numbers/