[PATCH 3/3] arm: vfp: Bounce undefined instructions in vectored mode

Russell King - ARM Linux linux at arm.linux.org.uk
Thu Sep 18 15:55:31 PDT 2014

On Thu, Sep 18, 2014 at 02:43:12PM -0700, Stephen Boyd wrote:
> From: Stepan Moskovchenko <stepanm at codeaurora.org>
> Certain ARM CPU implementations (e.g. Cortex-A15) may not raise a
> floating- point exception whenever deprecated short-vector VFP
> instructions are executed. Instead these instructions are treated
> as UNALLOCATED. Change the VFP exception handling code to emulate
> short-vector instructions even if FPEXC exception bits are not
> set.

Purely out of interest, how much use do these instructions have in
real programs?

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