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From: "ptk.prasertsuk at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/110035] Missed optimization for dependent
 assignment statements
Date: Sat, 03 Jun 2023 00:23:02 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D110035

--- Comment #7 from Pontakorn Prasertsuk <ptk.prasertsuk at gmail dot com> =
---
For the LLVM IR code of the snippet I provided, Clang's alias analysis can
prove that `new` call has no side effect to other memory location. This is
indicated by `noalias` keyword at the return value of the `new` call (_Znwm=
).

According to Clang's Language Reference:
"On function return values, the noalias attribute indicates that the functi=
on
acts like a system memory allocation function, returning a pointer to alloc=
ated
storage disjoint from the storage for any other object accessible to the
caller."

Is this possible for GCC alias analysis pass?=