[Hexagon] Use LiveRegUnits

[AZero13]

No description provided.

[kparzysz]

LGTM. You can remove the IsLive definition, as it's not used anymore. Thanks.

[AZero13]

LGTM. You can remove the IsLive definition, as it's not used anymore. Thanks.

Good now? Also I do not have commit permissions.

[AZero13]

LGTM. You can remove the IsLive definition, as it's not used anymore. Thanks.

I cannot do that because tests break and report bad machine code.

[kparzysz]

Please stop using force-pushes. They can mess up previous review comments.

[kparzysz]

There was a mistake in my comment: IsLive is equivalent to !LPR.available. Please restore the previous change and apply this correction.

[AZero13]

There was a mistake in my comment: IsLive is equivalent to !LPR.available. Please restore the previous change and apply this correction.

Done!

[kparzysz]

Please remove IsLive, LGTM with that change.

[AZero13]

Please remove IsLive, LGTM with that change.

I tried but then tests started failing, so I cannot do that.

[kparzysz]

I tried but then tests started failing, so I cannot do that.

The IsLive function checks if the register is in use (i.e. live). We then use it to set the kill flag on it: if the register is not live, then the use of it that we see (we're going backwards here) is the last one, so it's a kill. The available function in LiveRegUnits does exactly what IsLive is doing here. In this context "available" means "not in use", i.e. not live.

Is you replace the use of IsLive with !available it should work.

[AZero13]

I tried but then tests started failing, so I cannot do that.

The IsLive function checks if the register is in use (i.e. live). We then use it to set the kill flag on it: if the register is not live, then the use of it that we see (we're going backwards here) is the last one, so it's a kill. The available function in LiveRegUnits does exactly what IsLive is doing here. In this context "available" means "not in use", i.e. not live.

Is you replace the use of IsLive with !available it should work.

Done! @kparzysz

[kparzysz]

LGTM