summaryrefslogtreecommitdiff
path: root/PROJECTS
diff options
context:
space:
mode:
Diffstat (limited to 'PROJECTS')
-rw-r--r--PROJECTS27
1 files changed, 3 insertions, 24 deletions
diff --git a/PROJECTS b/PROJECTS
index 85cd22e060..0775bd2130 100644
--- a/PROJECTS
+++ b/PROJECTS
@@ -57,33 +57,12 @@ contact <bug-glibc@prep.ai.mit.edu>
[ 7] Several math functions have to be written:
- exp2
- - nearbyint
- each with float, double, and long double arguments. Writing these
- functions should be possible when following the implementation of
- the existing exp/log functions for other bases.
+ each with float, double, and long double arguments.
Beside this most of the complex math functions which are new in
- ISO C 9X. gcc already has support for numbers of complex type so the
- implementation should be possible today. I mention here the names
- and the way to write them (argument is z = x + iy):
-
- - sin(z) = 1/(2i) (e^(iz) - e^-(iz)) = sin(x) cosh(y) + i cos(x) sinh(y)
- - cos(z) = 1/2 (e^(iz) + e^-(iz)) = cos(x) cosh(y) - i sin(x) sinh(y)
- - tan(z) = 1/i (e^(iz) - e^-(iz))/(e^(iz) + e^-(iz))
- - cot(z) = i (e^(iz) + e^-(iz))/(e^(iz) - e^-(iz))
- - asin(z) = -i ln(iz + sqrt(1-z^2))
- - acos(z) = -i ln(z + sqrt(z^2-1))
- - atan(z) = 1/(2i) ln((1+iz)/(1-iz))
- - acot(z) = -1/(2i) ln((iz+1)/(iz-1))
- - tanh(z) = (e^z - e^-z)/(e^z + e^-z)
- - coth(z) = (e^z + e^-z)/(e^z - e^-z)
-
- All functions should we written with all the parallelism in mind.
- And assembler versions are highly expreciated since, e.g., the ix87
- FPU provides an `fsincos' instructions which is certainly useful for
- the `sin' function. The implementations for the normal math functions
- shows other optimization techniques.
+ ISO C 9X should be improved. Writing some of them in assembler is
+ useful to exploit the parallelism which often is available.
[ 8] If you enjoy assembler programming (as I do --drepper :-) you might