https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109509
Jan Hubicka <hubicka at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |hubicka at gcc dot gnu.org
--- Comment #3 from Jan Hubicka <hubicka at gcc dot gnu.org> ---
Chip,
can you specify which code it is?
LLVM only does always_inlines we handle during early optimization. Many of
cases where people run into inline bombs are with LTO where the inlining
happens cross-module. One option would be to ignore them at WPA
I did some work on chasing out non-linearities two years ago while enabling
auto-inlining at -O2. Plan to return to it this stage1.
Just checking the situation with basic inline bomb:
#include <stdio.h>
static inline __attribute__ ((always_inline)) void
test1()
{
printf ("ok\n");
}
#define D(i,j) static inline __attribute__ ((always_inline)) void test##j() {
test##i(); test##i(); }
D(1,2)
D(2,3)
D(3,4)
D(4,5)
D(5,6)
D(6,7)
D(7,8)
D(8,9)
D(9,10)
D(10,11)
D(11,12)
D(12,13)
D(13,14)
D(14,15)
D(15,16)
D(16,17)
D(17,18)
D(18,19)
int
main()
{
test19();
return 0;
}
GCC 13.0 compiles it in 126s with about 1GB of RAM. clang needs 12s.
Time report claims half of it is ipa passes:
callgraph ipa passes : 56.68 ( 45%) 1.08 ( 50%) 57.77 ( 45%)
1026M ( 81%)
But it is because early optimization is IPA pass an in fact we spent most of
time in IPA:
tree PTA : 97.49 ( 77%) 0.57 ( 26%) 98.10 ( 76%)
80M ( 6%)
Which is also run as part of early passes. Integratoin is 2.2s
