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Date: Tue, 16 Sep 2025 11:44:26 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Fangrui Song <maskray@sourceware.org>
Cc: Indu Bhagat <indu.bhagat@oracle.com>, Steven Rostedt <rostedt@goodmis.org>,
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        Serhei Makarov <smakarov@redhat.com>,
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Subject: Re: Unaligned access trade-offs for SFrame FRE layout
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On Tue, Sep 16, 2025 at 09:32:30AM -0700, Fangrui Song wrote:
> The read32le(p) function is either a standard read or a byte-swapped
> read.

You should never overcomplicate things by doing byte-swaps.  Instead,
just say what you mean:

u32 read32le(u8 *p)
{
	return p[0] + 0x100*p[1] + 0x10000*p[2] + 0x1000000*p[3];
}

or something like that.  The compiler can optimise such things just
fine!  There is no need to go via extra indirections.


Segher