It looks like this bug is caused by the inliner refusing to inline
across comments (so the actual reproduce code is):
Y = Hp + 4
Z = Y + 1
// comment
R1 = Z
becomes
Z = Hp + 5
// comment
R1 = Z
Maybe from a pretty-printing perspective this might be the right thing to
On 23/03/2011 13:48, Edward Z. Yang wrote:
I made a different change, which, with constant folding, should be just as
good: allocate a new register, so everything is kept in SSA. I've sent
the updated patch.
One infelicity is that the inliner doesn't seem to manage to inline:
Y = Hp + 4
I made a different change, which, with constant folding, should be just as
good: allocate a new register, so everything is kept in SSA. I've sent
the updated patch.
One infelicity is that the inliner doesn't seem to manage to inline:
Y = Hp + 4
Z = Y + 1
R1 = Z
into
R1 = Hp + 5
It occurs to me that this patch kind of generates stupid code when no
tag bit is necessary: it does:
abc = Hp + 4
abc = abc
So one minor adjustment would be to check if the tag bit is zero and
omit the assignment.
Another possibility is to pattern match on the first expression and
fold t
