[clang] [Clang][Interp] Implement constexpr vector unary operators +, -, ~, ! (PR #105996)

[Timm Baeder via cfe-commits]

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@@ -5312,6 +5314,149 @@ bool Compiler<Emitter>::VisitComplexUnaryOperator(const UnaryOperator *E) {
   return true;
 }
 
+template <class Emitter>
+bool Compiler<Emitter>::VisitVectorUnaryOp(const UnaryOperator *E) {
+  const Expr *SubExpr = E->getSubExpr();
+  assert(SubExpr->getType()->isVectorType());
+
+  if (DiscardResult)
+    return this->discard(SubExpr);
+
+  std::optional<PrimType> ResT = classify(E);
+  auto prepareResult = [=]() -> bool {
+    if (!ResT && !Initializing) {
+      std::optional<unsigned> LocalIndex = allocateLocal(SubExpr);
+      if (!LocalIndex)
+        return false;
+      return this->emitGetPtrLocal(*LocalIndex, E);
+    }
+
+    return true;
+  };
+
+  // The offset of the temporary, if we created one.
+  unsigned SubExprOffset = ~0u;
+  auto createTemp = [=, &SubExprOffset]() -> bool {
+    SubExprOffset = this->allocateLocalPrimitive(SubExpr, PT_Ptr, true, false);
+    if (!this->visit(SubExpr))
+      return false;
+    return this->emitSetLocal(PT_Ptr, SubExprOffset, E);
+  };
+
+  const auto *VecT = SubExpr->getType()->getAs<VectorType>();
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tbaederr wrote:

The convention is that things ending in `T` are `PrimType`s. Call this `VT` or `VecTy`.

https://github.com/llvm/llvm-project/pull/105996