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Date: Wed, 29 May 2024 01:54:21 +0200
From: Andrea Parri <parri.andrea@gmail.com>
To: Alexandre Ghiti <alexghiti@rivosinc.com>
Cc: Jonathan Corbet <corbet@lwn.net>,
	Paul Walmsley <paul.walmsley@sifive.com>,
	Palmer Dabbelt <palmer@dabbelt.com>,
	Albert Ou <aou@eecs.berkeley.edu>,
	Peter Zijlstra <peterz@infradead.org>,
	Ingo Molnar <mingo@redhat.com>, Will Deacon <will@kernel.org>,
	Waiman Long <longman@redhat.com>, Boqun Feng <boqun.feng@gmail.com>,
	Arnd Bergmann <arnd@arndb.de>, Leonardo Bras <leobras@redhat.com>,
	Guo Ren <guoren@kernel.org>, linux-doc@vger.kernel.org,
	linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org,
	linux-arch@vger.kernel.org
Subject: Re: [PATCH 2/7] riscv: Implement cmpxchg8/16() using Zabha
Message-ID: <ZlZurXUUUfXHZJaX@andrea>
References: <20240528151052.313031-1-alexghiti@rivosinc.com>
 <20240528151052.313031-3-alexghiti@rivosinc.com>
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> +zabha:									\
> +	__asm__ __volatile__ (						\
> +		prepend							\
> +		"	amocas" cas_sfx " %0, %z2, %1\n"		\
> +		append							\
> +		: "+&r" (r), "+A" (*(p))				\
> +		: "rJ" (n)						\
> +		: "memory");						\

Couldn't a platform have Zabha but not have Zacas?  I don't see how this
asm goto could work in such case, what am I missing?

  Andrea