Messages in this thread | | | From | David Laight <> | Subject | RE: [PATCH v2] hwmon: (dell-smm) Improve assembly code | Date | Sun, 20 Feb 2022 18:03:15 +0000 |
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From: Guenter Roeck > Sent: 20 February 2022 15:30 > > On 2/20/22 04:20, David Laight wrote: > > From: Armin Wolf > >> Sent: 19 February 2022 21:10 > >> > >> The new assembly code works on both 32 bit and 64 bit > >> cpus and allows for more compiler optimisations by not > >> requiring smm_regs to be packed. Also since the > >> SMM handler seems to modify the carry flag, the new > >> code informs the compiler that the flags register > >> needs to be saved/restored. Since clang runs out of > >> registers on 32 bit x86 when using CC_OUT, we need > >> to execute "setc" ourself. > > > > You always need to save anything from the flags register > > inside the asm block - it is never valit afterwards. > > > > Does that matter here ? I thought setcc is used to get the carry flag.
The code is ok, just the comment is not really right.
David
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