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Re: [PATCH] [C++] speedup cp_tree_chain_matters_p
Andrew Pinski <firstname.lastname@example.org> writes:
> On Mar 30, 2004, at 03:12, Zack Weinberg wrote:
>> No. Find out why sibcall optimization doesn't trigger for the
>> original code and fix that instead.
> The reason why it is not sibcalled is because c_tree_chain_matters_p
> returns an int so the || statement becomes f()!=0||g()!=0 which becomes
> if (f()!=0)
> return true;
> return g()!=0;
> So one thing to do is change the return type c_tree_chain_matters_p to
> return bool but that will still not fix it.
> This example is not sibcalled at all:
> _Bool f();
> _Bool g();
> _Bool h()
> return f() || g();
Sibcall optimization should apply to both these examples. There's no
good reason why users should have to obfuscate their code to make it
trigger. Does tree-ssa do better here?