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From: kamlesh kumar <kamleshbhalui@gmail.com>
Date: Thu, 16 May 2019 02:41:00 -0000
Message-ID: <CABKRkgjMN1xnUGvcD2AQXSB3-Kj4ZAfvqpzdZ3i1psvWKCKerg@mail.gmail.com>
Subject: regarding https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89924
To: gcc@gcc.gnu.org, Jan Hubicka <hubicka@ucw.cz>
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X-SW-Source: 2019-05/txt/msg00127.txt.bz2

Hi devs,
I am looking into subjected issue.
consider below testcase.
$test.cpp
class A {
public:
    virtual int value() { return 1; }
};

class  B final : public A {
public:
    int value(){ return 2; }
};
int test(A* b) {
    return b->value() + 11;
}
void foo_test(B*b)
{
test(b);
}
Here gcc is unable to devirtualize the call to value into the test, because
type information is not being propogated from foo_test to test.
So this is what i am trying to do to make devirtualization happen:

First we can inline the function test into foo_test.
And then update the type in the OBJ_TYPE_REF.
so that devirtualization can be applied.
Like to know your thought before going ahead.

./Kamlesh