From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id C0B8B385626B; Mon, 6 Jun 2022 17:00:06 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org C0B8B385626B From: "hpa at zytor dot com" To: gcc-bugs@gcc.gnu.org Subject: [Bug target/103503] RFE: no save registers attribute Date: Mon, 06 Jun 2022 17:00:06 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: gcc X-Bugzilla-Component: target X-Bugzilla-Version: 12.0 X-Bugzilla-Keywords: X-Bugzilla-Severity: enhancement X-Bugzilla-Who: hpa at zytor dot com X-Bugzilla-Status: UNCONFIRMED X-Bugzilla-Resolution: X-Bugzilla-Priority: P3 X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: gcc-bugs@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-bugs mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 06 Jun 2022 17:00:06 -0000 https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D103503 --- Comment #4 from H. Peter Anvin --- The interrupt attribute typically does two things: 1. It changes the return instruction; 2. It marks all registers as saved. 2 is exactly the *opposite* of what I want; I would like to improve perform= ance by the fact that the compiler-invisible entry flow has already saved all registers, whether or not they are saved in the ABI. Thus, I would like it = to treat all (non-fixed) registers as *clobbered*, not *saved*. Ideally, "nosaved" and "interrupt" should be possible to use together, to g= et effect #1 of the interrupt attribute, but that is usually less important.=