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Date: Sat, 18 Apr 2020 17:32:09 +0200 (CEST)
From: Marc Glisse <marc.glisse@inria.fr>
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To: William Tambe <tambewilliam@gmail.com>
cc: gcc-help <gcc-help@gcc.gnu.org>
Subject: Re: prevent zero-extension when using a memory load instruction
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On Sat, 18 Apr 2020, William Tambe via Gcc-help wrote:

> In the machine description file, is there a way to tell GCC that a
> memory load instruction already zero-extend such that it does not try
> to apply zero-extension ?

I would look at it the other way around: you can tell GCC what asm to 
generate for a zero_extend with a memory operand. Or did you have a 
specific example in mind?

-- 
Marc Glisse