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From: "powerboat9.gamer at gmail dot com" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/113164] New: [missed optimization] struct fields should not alias Date: Thu, 28 Dec 2023 14:55:57 +0000 [thread overview] Message-ID: <bug-113164-4@http.gcc.gnu.org/bugzilla/> (raw) https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113164 Bug ID: 113164 Summary: [missed optimization] struct fields should not alias Product: gcc Version: 13.2.1 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end Assignee: unassigned at gcc dot gnu.org Reporter: powerboat9.gamer at gmail dot com Target Milestone: --- I have the following code > struct sss { > int a; > int b; > }; > > int foo(struct sss *a, struct sss *b) { > return &a->a == &b->b; > } When I compile it with > gcc -c -O3 -Wall -Wextra test.c I get > 0000000000000000 <foo>: > 0: 48 83 c6 04 add $0x4,%rsi > 4: 31 c0 xor %eax,%eax > 6: 48 39 fe cmp %rdi,%rsi > 9: 0f 94 c0 sete %al > c: c3 ret , but GCC should be able to infer that the two pointers being compared can not alias.
next reply other threads:[~2023-12-28 14:55 UTC|newest] Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top 2023-12-28 14:55 powerboat9.gamer at gmail dot com [this message] 2023-12-28 18:22 ` [Bug middle-end/113164] " pinskia at gcc dot gnu.org 2024-01-08 14:16 ` rguenth at gcc dot gnu.org 2024-05-16 12:47 ` rguenth at gcc dot gnu.org
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