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From: "vineetg at rivosinc dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/108987] [13 Regression] RISC-V: shiftadd cost model bug
 needlessly preferring syth_multiply
Date: Mon, 06 Mar 2023 21:50:57 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D108987

Vineet Gupta <vineetg at rivosinc dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         Resolution|---                         |FIXED
             Status|UNCONFIRMED                 |RESOLVED

--- Comment #2 from Vineet Gupta <vineetg at rivosinc dot com> ---
This is now merged in trunk

commit 7e52f4420ffb0946dfc97704d72fa8aa67251495
Author: Vineet Gupta <vineetg@rivosinc.com>
Date:   Wed Mar 1 11:53:15 2023 -0800

RISC-V: costs: miscomputed shiftadd_cost triggering synth_mult [PR/108987]

This showed up as dynamic icount regression in SPEC 531.deepsjeng with upst=
ream
gcc (vs. gcc 12.2). gcc was resorting to synthetic multiply using shift+add=
(s)
even when multiply had clear cost benefit.

....=