https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64143
Bug ID: 64143
Summary: Add option -felide-aliases
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: enhancement
Priority: P3
Component: other
Assignee: unassigned at gcc dot gnu.org
Reporter: r.p.nicholl at gmail dot com
I am suggesting to add the option -felide-aliases.
For certian functions, perhaps those marked "hot", where the compiler can
determine the widths of access of any pointers used, the compiler would check
on entry, if certian pointers alias eachother or not, and then choose between
multiple overloads of the function depending on if this pointer aliasing
occured.
So for example, when multiplying to matricies and putting the results in an
index, if this optimization was enabled, on entry, it would check if the result
and the other arguments overlap or not. Then it would jump to the correct
function depending of the result of that check.
It is also possible, during profiling, that the compiler may check which types
of aliasing are more common, such as the case where the two inputs overlap
commonly, but it is unlikey for the inputs to overlap with the output.
