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Diffstat (limited to 'PROJECTS')
| -rw-r--r-- | PROJECTS | 27 |
1 files changed, 3 insertions, 24 deletions
@@ -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 |