Ruby: Split basic blocks around constant conditionals

[hvitved]

In cases such as

if x or y
    foo
else
    bar

we have a CFG that looks like

graph TD;

xvar(x);
yvar(y);
foo(foo);
bar(bar);
orfalse("or [false]");
ortrue("or [true]");

xvar-- false -->yvar;
xvar-- true -->ortrue;
yvar-- false -->orfalse;
yvar-- true -->ortrue;

ortrue-- true -->foo;
orfalse-- false -->bar;

Loading

In order to record the fact that x or y true-controls foo (resp. false-controls bar), we need to make sure that a new basic block is started at both foo and bar; that is, we split the existing basic blocks into two.

[aibaars]

Looks good to me.

[aibaars]

Let's use a different name in the else clause to make it easier to validate the expected output.

Suggested change

	foo
	bar

[aibaars]

Also add a test case for and and perhaps not as well.

[hvitved]

@aibaars : Comments addressed, and DCA looks fine.

[aibaars]

LGTM