search for: getconstantvregv

...> You’re doing the right thing. > That’s a known limitation that we’ve discussed in https://reviews.llvm.org/D59227 <https://reviews.llvm.org/D59227> but we didn’t really reach a conclusion back them. > Short term, I believe you’re right, we should patch up the GISel emitter to use getConstantVRegVal instead of looking directly for G_CONSTANT. That's not as easy as you make it sound :-) but let's suppose we can recognize enough of the underlying pattern to be able to use getConstantVRegVal() instead of needing to do a direct translation of the SelectionDAG pattern. In the SelectionDA...

...ngs actually work. Namely, any ImmLeaf pattern will fail to match if there is a (TRUNC/ZEXT/SEXT) applied to the constant operand, all of which are commonly created through Legalization. This is due to G_CONSTANT being explicitly looked for by the tablegened code, rather than code that makes use of getConstantVRegVal. Is there supposed to be a constant folding pass before Instruction Selection? CSE does not fold past unaries applied to operands, I'm surely missing a pass somewhere... Thanks, - Alex Davies -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.llv...