https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87055
Bug ID: 87055
Summary: Unoptimal address calculation
Product: gcc
Version: 9.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: ubizjak at gmail dot com
Target Milestone: ---
Following testcase:
--cut here--
int a[256];
int foo (int i)
{
return a[i+1];
}
--cut here--
compiles on x86_64 (-O2) to:
addl $1, %edi
movslq %edi, %rdi
movl a(,%rdi,4), %eax
ret
clang merges the addition with the address:
movslq %edi, %rax
movl a+4(,%rax,4), %eax
retq
Related: PR54589
