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Date: Tue, 9 Jul 2024 13:46:29 +0200
From: Christoph Hellwig <hch@lst.de>
To: Yangyu Chen <cyy@cyyself.name>
Cc: Christoph Hellwig <hch@lst.de>, iommu@lists.linux.dev,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Marek Szyprowski <m.szyprowski@samsung.com>,
	Robin Murphy <robin.murphy@arm.com>
Subject: Re: [PATCH -fixes] dma-mapping: add default implementation to
 arch_dma_{set|clear}_uncached
Message-ID: <20240709114629.GB6959@lst.de>
References: <tencent_A5ED71472ADCAF18F59085464CBE23C12A07@qq.com> <20240709111901.GC4421@lst.de> <tencent_651BC4D11C9730062064ACB186AF4A904005@qq.com>
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On Tue, Jul 09, 2024 at 07:39:29PM +0800, Yangyu Chen wrote:
> The reason is that some optimizations failed to apply after adding
> some passes. I will fix the compiler later. Whatever, we should not
> rely on this optimization to get the code being successfully compiled.

The Linux kernel relies on constant propagation and dead code
eliminiation a lot to make code simpler and more readable.