https://gcc.gnu.org/bugzilla/show_bug.cgi?id=65413
--- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> ---
Actually, similarly inefficient code is generated even for aggregates that do
fit into a register. The trigger appears to be that the aggregate not take up
an even multiple of a register. For example, returning a "struct { char a[7];
}" results in the code below. Another example is "struct { short a[3]; }"
foo:
mr 10,3
rlwinm 8,3,0,0xff
li 9,0
rldicl 7,10,48,56
rldimi 9,8,0,56
rldicl 8,10,56,56
rldimi 9,8,8,48
rldicl 10,10,40,56
srdi 8,3,32
rldimi 9,7,16,40
rldimi 9,10,24,32
rlwinm 10,8,0,0xff
rldimi 9,10,32,24
rldicl 8,8,56,56
rldicl 3,3,16,56
rldimi 9,8,40,16
rldimi 9,3,48,8
mr 3,9
blr
