To just add another data-point, metaprograms like the following are very
common. Consider
template <int i>
struct Add
{
static inline int doit(int *x)
{
return Add<i-1>::doit(x)+x[i];
}
};
template <>
struct Add<0>
{
static inline int doit(int *x)
{
return x[0];
}
};
template <int i>
inline int add(int *x)
{
return Add<i>::doit(x);
}
int foo(int *x)
{
return add<3>(x);
}
int bar(int *x)
{
int i, r=0;
for (i=0; i<4; ++i)
r += x[i];
return r;
}
int baz(int *x)
{
return x[0]+x[1]+x[2]+x[3];
}
The size estimates after inlining (before in paranthesis) are
foo bar baz
3.4 12 (11) 11 7
4.0 29 (13) 18 17
4.0 patched 6 (10) 11 6
which shows:
1. estimates for 4.0 are way higher than for 3.4 in general
(while we still have the same inlining limits)
2. INSNS_PER_CALL (10) is low for 4.0 compared to 3.4
if you consider the overall increase. Something like
at least 15 would be appropriate.
3. the new size estimate for 4.0 produces slightly lower
estimates than 3.4 which suggests to at least change
max-inline-insns-auto back to 100 as it was in 3.4 from
now 120.
Richard.
