[llvm] [llubi] Add support for undef values (PR #205602)

[Nikita Popov via llvm-commits]

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@@ -310,30 +342,43 @@ std::optional<AnyValue> Context::evaluateConstantExpression(ConstantExpr *CE) {
       }
     };
 
+    bool Cacheable = LHS->isCacheable() && RHS->isCacheable();
+
     if (CE->getType()->isVectorTy()) {
       auto &LHSVec = LHS->asAggregate();
       auto &RHSVec = RHS->asAggregate();
       std::vector<AnyValue> ResVec;
       ResVec.reserve(LHSVec.size());
       for (const auto &[ScalarLHS, ScalarRHS] : zip(LHSVec, RHSVec))
         ResVec.push_back(ScalarEval(ScalarLHS, ScalarRHS));
-      return std::move(ResVec);
+      return MaterializedConstant(std::move(ResVec), Cacheable);
     }
 
-    return ScalarEval(*LHS, *RHS);
+    return MaterializedConstant(ScalarEval(*LHS, *RHS), Cacheable);
   }
 }
 
-const AnyValue *Context::getConstantValue(Constant *C) {
+const MaterializedConstant *Context::getConstantValue(Constant *C) {
   auto It = ConstCache.find(C);
   if (It != ConstCache.end())
     return &It->second;
 
-  std::optional<AnyValue> Val = getConstantValueImpl(C);
-  if (!Val)
+  MaterializedConstant Val = getConstantValueImpl(C);
+  if (Val.isNone())
     return nullptr;
+  if (!Val.isCacheable()) {
+    assert(NoncacheableConstBuffer.getBytesAllocated() <=
+               1024 * sizeof(MaterializedConstant) &&
+           "");
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nikic wrote:

Empty message?

https://github.com/llvm/llvm-project/pull/205602