https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80283
--- Comment #14 from Michael_S <already5chosen at yahoo dot com> --- Created attachment 41293 --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41293&action=edit another case of bad vector register allocation Here is another case of bad allocation of SIMD register that hopefully can help Berndt. This case does not appear to depend on optimization level or on -fno-tree-ter. Bad allocation happens with all versions of gcc that I tested on godbolt, but the level of damage is higher with newer versions. # of spills of accumulators in the inner loop as function of value of UNROLL and of version of gcc: UNROLL 1 2 3 4 gcc 4.9.4 0 2 1 1 gcc 5.4 0 2 1 1 gcc 6.3 0 2 1 2 gcc 7 0 2 1 2 Link to goldbolt: https://godbolt.org/g/N49vBs
