http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53125
Bug #: 53125
Summary: Very slow register allocation on SPARC
Classification: Unclassified
Product: gcc
Version: 4.7.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: rtl-optimization
AssignedTo: unassig...@gcc.gnu.org
ReportedBy: i...@airs.com
CC: r...@gcc.gnu.org, vmaka...@redhat.com
Target: sparc-sun-solaris2.11
Created attachment 27244
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=27244
Test case
The attached test case is a conversion to C of a machine generated test case in
Go (the machine generated Go source is in
gcc/testsuite/go.test/test/cmpldivide1.go).
When I compile this test case without optimization on an x86_64 GNU/Linux
system, it takes 5.8 seconds. When I compile it without optimization on a
SPARC Solaris 2.11 system, it takes 2 minutes 32.8 seconds. The SPARC machine
is slower than the x86_64 machine. But it's not that much slower.
According to -ftime-report on the SPARC system, 45% of the time is "register
information" and 41% of the time is "integrated RA."
Since the file is machine generated, I would be willing to accept a 2 1/2
minute compilation time with optimization. But without optimization it is just
too slow. And the discrepancy with x86_64 is extreme.
