[PATCH] Move VFP4 predicate inside UseFusedMAC

[Daniel Stewart]

Ahh, I see. The definition of HasVFP4 is 

def HasVFP4          : Predicate<"Subtarget->hasVFP4()">,
                                 AssemblerPredicate<"FeatureVFP4", "VFP4">;

which has the AssemblerPredicate, which you're saying is being checked at
assembly time?

So, the HasVFP4 predicate check should not be removed from the various
instructions. Shouldn't UseFusedMAC still check for VFP4 inside its
predicate, rather than relying on the instruction to include HasVF4 inside
it's predicate checks? Just to ensure safety and be in line with the
DontUseFusedMAC? Or am I missing something else?

Daniel

-----Original Message-----
From: Tim Northover [mailto:t.p.northover at gmail.com] 
Sent: Wednesday, December 04, 2013 10:55 AM
To: Daniel Stewart
Cc: llvm-commits
Subject: Re: [PATCH] Move VFP4 predicate inside UseFusedMAC

> Basically, UseFusedMAC isn't being checked by the assembler and it 
> would give incorrect results even if it was.

Just a quick example:

echo vfma.f32 d0, d1, d2 | llvm-mc -triple=armv7 -mcpu=cortex-a8

Tim.