Re^2: Why isn't return removed from optree?

I don't think you can avoid that, but I'm not completely certain.

You might have to remove the pushmark along with the return. When you do that, you get exactly the same opcode tree as if you hadn't used the return keyword, so it's obviously safe.

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Re^3: Why isn't return removed from optree? by ikegami (Patriarch) on Dec 29, 2008 at 08:45 UTC
Ah-ha! I found a situation where `return` can't simply be omitted. >perl -MO=Concise,f -e"sub f { return ($x,$y) }" main::f: 6 <1> leavesub[1 ref] K/REFC,1 ->(end) - <@> lineseq KP ->6 1 <;> nextstate(main 1 -e:1) v ->2 5 <@> return KP ->6 2 <0> pushmark s ->3 - <1> ex-rv2sv sK/1 ->4 3 <#> gvsv[x] s ->4 - <1> ex-rv2sv sK/1 ->5 4 <#> gvsv[y] s ->5 -e syntax OK >perl -MO=Concise,f -e"sub f { ($x,$y) }" main::f: 6 <1> leavesub[1 ref] K/REFC,1 ->(end) - <@> lineseq KP ->6 1 <;> nextstate(main 1 -e:1) v ->2 5 <@> list KP ->6 2 <0> pushmark s ->3 - <1> ex-rv2sv sK/1 ->4 3 <#> gvsv[x] s ->4 - <1> ex-rv2sv sK/1 ->5 4 <#> gvsv[y] s ->5 -e syntax OK [download] That gives me something to look at.	[reply] [d/l] [select]
Re^4: Why isn't return removed from optree? by merlyn (Sage) on Dec 29, 2008 at 11:17 UTC
But how are they different? Those both do exactly the same thing in both a scalar and list context, as far as I could tell. -- Randal L. Schwartz, Perl hacker	[reply]
Re^5: Why isn't return removed from optree? by ikegami (Patriarch) on Dec 29, 2008 at 20:33 UTC
Are you suggesting that the optimizer should replace the `return` with `list`? I don't remember seeing it replace one op for another except in constant folding.	[reply] [d/l] [select]