TableGen/CodeGenDAGPatterns: addPredicateFn only once

[nhaehnle]

Summary

The predicate function is added in InlinePatternFragments, no need to
do it here. As a result, all uses of addPredicateFn are located in
InlinePatternFragments.

Test confirmed that there are no changes to generated files when
building all (non-experimental) targets.

Change-Id: I720e42e045ca596eb0aa339fb61adf6fe71034d5

[RKSimon]

Any perf numbers? For instance, on x86 -gen-dag-isel

[nhaehnle]

In D51993#1232208, @RKSimon wrote:

Any perf numbers? For instance, on x86 -gen-dag-isel

No, and I don't see why we'd care. The motivation was purely code cleanup, and I don't see how the performance could get worse.

[RKSimon]

In D51993#1232277, @nhaehnle wrote:

In D51993#1232208, @RKSimon wrote:

Any perf numbers? For instance, on x86 -gen-dag-isel

No, and I don't see why we'd care. The motivation was purely code cleanup, and I don't see how the performance could get worse.

Curiosity - I've been trying very hard to reduce tablegen build times over the past few months.

[hfinkel]

In D51993#1232426, @RKSimon wrote:

In D51993#1232277, @nhaehnle wrote:

In D51993#1232208, @RKSimon wrote:

Any perf numbers? For instance, on x86 -gen-dag-isel

No, and I don't see why we'd care. The motivation was purely code cleanup, and I don't see how the performance could get worse.

Curiosity - I've been trying very hard to reduce tablegen build times over the past few months.

Sounds great. In the mean time, however, I see no reason not to approve this patch. Seems like the performance would only get better.

llvm/trunk/utils/TableGen/CodeGenDAGPatterns.h

public:
   }
   void clearPredicateFns() { PredicateFns.clear(); }
   void setPredicateFns(const std::vector<TreePredicateFn> &Fns) {
     assert(PredicateFns.empty() && "Overwriting non-empty predicate list!");
     PredicateFns = Fns;
   }
   void addPredicateFn(const TreePredicateFn &Fn) {
     assert(!Fn.isAlwaysTrue() && "Empty predicate string!");
-    if (!is_contained(PredicateFns, Fn))
-      PredicateFns.push_back(Fn);
+    assert(!is_contained(PredicateFns, Fn) && "predicate applied recursively");
   }
 
   Record *getTransformFn() const { return TransformFn; }
   void setTransformFn(Record *Fn) { TransformFn = Fn; }
 
   /// getIntrinsicInfo - If this node corresponds to an intrinsic, return the
   /// CodeGenIntrinsic information for it, otherwise return a null pointer.
   const CodeGenIntrinsic *getIntrinsicInfo(const CodeGenDAGPatterns &CDP) const;

llvm/trunk/utils/TableGen/CodeGenDAGPatterns.cpp

for (unsigned j = 0, e = OpsList->getNumArgs(); j != e; ++j) {
       OperandsSet.erase(ArgNameStr);
       Args.push_back(ArgNameStr);
     }
 
     if (!OperandsSet.empty())
       P->error("Operands list does not contain an entry for operand '" +
                *OperandsSet.begin() + "'!");
 
-    // If there is a code init for this fragment, keep track of the fact that
-    // this fragment uses it.
-    TreePredicateFn PredFn(P);
-    if (!PredFn.isAlwaysTrue())
-      for (auto T : P->getTrees())
-        T->addPredicateFn(PredFn);
-
     // If there is a node transformation corresponding to this, keep track of
     // it.
     Record *Transform = Frag->getValueAsDef("OperandTransform");
     if (!getSDNodeTransform(Transform).second.empty())    // not noop xform?
       for (auto T : P->getTrees())
         T->setTransformFn(Transform);
   }