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From: "652023330028 at smail dot nju.edu.cn" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/111718] Missed optimization of '(a+a)/a'
Date: Sun, 08 Oct 2023 03:03:34 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D111718

--- Comment #2 from Yi <652023330028 at smail dot nju.edu.cn> ---
We noticed one change between gcc-13.2 and the current gcc-trunk:

https://godbolt.org/z/j5Mnvno9n

In the following code, gcc-13.2 does not yet have the ability to optimize as
expected, but on gcc-trunk, it does.

unsigned n1,n2;
void func1(unsigned a){
    if(a<=3D10 || a>=3D20)
        return;
    n2=3D(a+a)/a;
}


Maybe this change will help solve this issue?=