https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66002
Bug ID: 66002
Summary: paq8p benchmark 50% slower than clang on sandybridge
Product: gcc
Version: 6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
Assignee: unassigned at gcc dot gnu.org
Reporter: trippels at gcc dot gnu.org
Target Milestone: ---
Created attachment 35451
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35451&action=edit
testcase
On sandybridge I get:
trippels@gcc75 ~ % g++ -O3 -march=native paq8p.ii -o paq8p
trippels@gcc75 ~ % time ./paq8p -4 file1.in
Creating archive with 1 file(s)...
file1.in 262144 -> 262371
262144 -> 262400
Extracting 1 file(s) from archive -4
Comparing file1.in 262144 -> identical
./paq8p -4 file1.in 61.82s user 0.08s system 100% cpu 1:01.90 total
trippels@gcc75 ~ % clang++ -w -O3 -march=native paq8p.ii -o paq8p
trippels@gcc75 ~ % time ./paq8p -4 file1.in
...
./paq8p -4 file1.in 29.60s user 0.12s system 100% cpu 29.715 total
Intel compiler:
./paq8p -4 file1.in 22.00s user 0.09s system 99% cpu 22.092 total
