[PATCH] D28820: Warn when calling a non interrupt function from an interrupt on ARM

[Jonathan Roelofs via Phabricator via cfe-commits]

jroelofs added a comment.

In https://reviews.llvm.org/D28820#649726, @efriedma wrote:

> Why can't the compiler handle this case itself transparently?  According to your description, the interrupt calling convention is different from the normal hard-float AAPCS calling convention: the VFP registers are all callee-save.  The compiler knows this; it should be able to insert the appropriate spills itself.


There would be a big performance penalty for ISRs with callees that don't use VFP regs.


https://reviews.llvm.org/D28820