[llvm-dev] a tagged architecture, the elephant in the undef / poison room

[Peter Lawrence via llvm-dev]

John,
         Here’s what I’m getting at

“Poison” is an attribute of a “value”, not a “value” itself.

“Poison” is an analysis result, and we should think about implementing it as such,
just like we do constant and range analysis.

Turning “poison” into a “value” means all “values” now have in addition to
a bit pattern an extra attribute (IE a tag).


Peter Lawrence.