rust/src/test/run-pass/float_math.rs, branch 1.10.0https://github.com/rust-lang/rust
http://git.dreamy.place/mirrors/rust/atom?h=1.10.02016-03-19T21:35:28+00:00Update float_math test to not use constants2016-03-19T21:35:28+00:00Ulrik Sverdrupbluss@users.noreply.github.com2016-03-19T21:23:45+00:00urn:sha1:ba89b255e86817e0a2f43198a6b802dafbc6ae9eAdd intrinsics for float arithmetic with `fast` flag enabled2016-03-18T16:31:41+00:00Ulrik Sverdrupbluss@users.noreply.github.com2016-03-14T23:01:12+00:00urn:sha1:2dbac1fb8ed43cbcd160855803d50a51c38b8cee
`fast` a.k.a UnsafeAlgebra is the flag for enabling all "unsafe"
(according to llvm) float optimizations.
See LangRef for more information http://llvm.org/docs/LangRef.html#fast-math-flags
Providing these operations with less precise associativity rules (for
example) is useful to numerical applications.
For example, the summation loop:
let sum = 0.;
for element in data {
sum += *element;
}
Using the default floating point semantics, this loop expresses the
floats must be added in a sequence, one after another. This constraint
is usually completely unintended, and it means that no autovectorization
is possible.