https://issues.dlang.org/show_bug.cgi?id=16503
Issue ID: 16503
Summary: [ndslice] prevents fastmath LDC attribute
Product: D
Version: D2
Hardware: All
OS: All
Status: NEW
Severity: major
Priority: P1
Component: phobos
Assignee: [email protected]
Reporter: [email protected]
Slice
{
front
opIndex
ptr
...
}
auto sl1 = slice!double(...);
auto sl2 = slice!double(...);
@fastmath ... {
// loop for strides == 1
c += sl1.ptr[i] * sl2.ptr[i];
}
c's computation can not be fully optimized because Slice primitives has not
fastmath attribute.
In the same time this is safe TODO:
Slice
{
@fastmath:
front
opIndex
...
}
auto sl = slice!double(...);
... { // no fastmath
// loop for strides == 1
c += sl1.ptr[i] * sl2.ptr[i];
}
No optimisations in the last case.
So, we can just mark all ndslice except mapSlice as @fastmath :-)
--
