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Re: [PATCH, AArch64] Add secondary reload for immediates into FP_REGS

On 30/07/13 14:28, Ian Bolton wrote:
Our movdi_aarch64 pattern allows moving a constant into an FP_REG,
but has the constraint Dd, which is stricter than the one for
moving a constant into a CORE_REG.  This is due to restricted values
allowed for MOVI instructions.

Due to the predicate for the pattern allowing any constant that is
valid for the CORE_REGs, we can run into situations where IRA/reload
has decided to use FP_REGs but the value is not actually valid for

This patch introduces a secondary reload to handle this case.

Supplied with testcase that highlighted original problem.
Tested on Linux GNU regressions.

OK for trunk?


2013-07-30  Ian Bolton  <>

         * config/aarch64/aarch64.c (aarch64_secondary_reload)): Handle
         constant into FP_REGs that is not valid for MOVI.

         * New test.

I think you should be using TARGET_PREFERRED_RELOAD_CLASS for this case. The documentation for that seems to be describing exactly the situation you are facing.


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