https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113572
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Given the vector-builder.h comment, I believe { -1, 0, ... } with npatterns 1
and nelts-per-pattern 2 means { -1, 0, 0, 0, 0, 0, 0, ... }
/* This class is a wrapper around auto_vec<T> for building vectors of T.
It aims to encode each vector as npatterns interleaved patterns,
where each pattern represents a sequence:
{ BASE0, BASE1, BASE1 + STEP, BASE1 + STEP*2, BASE1 + STEP*3, ... }
The first three elements in each pattern provide enough information
to derive the other elements. If all patterns have a STEP of zero,
we only need to encode the first two elements in each pattern.
If BASE1 is also equal to BASE0 for all patterns, we only need to
encode the first element in each pattern. The number of encoded
elements per pattern is given by nelts_per_pattern.
Because this is just one pattern (so not interleaved) and doesn't have STEP (so
STEP is zero) and has 2 elements (so BASE0 and BASE1, rather than just BASE0 ==
BASE1).
