[clang] [X86][Clang] VectorExprEvaluator::VisitCallExpr / InterpretBuiltin - add SSE/AVX VPTEST/VTESTPD/VTESTPS intrinsics to be used in constexpr (PR #160428)

[Simon Pilgrim via cfe-commits]

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@@ -2889,6 +2889,66 @@ static bool interp__builtin_blend(InterpState &S, CodePtr OpPC,
   return true;
 }
 
+static bool interp__builtin_ia32_test_op(
+    InterpState &S, CodePtr OpPC, const CallExpr *Call,
+    llvm::function_ref<bool(const APInt &A, const APInt &B)> Fn) {
+  const Pointer &RHS = S.Stk.pop<Pointer>();
+  const Pointer &LHS = S.Stk.pop<Pointer>();
+
+  assert(LHS.getNumElems() == RHS.getNumElems());
+  assert(LHS.getFieldDesc()->isPrimitiveArray() &&
+         RHS.getFieldDesc()->isPrimitiveArray());
+
+  if (!S.getASTContext().hasSameUnqualifiedType(getElemType(LHS),
+                                                getElemType(RHS)))
+    return false;
+
+  const unsigned SourceLen = LHS.getNumElems();
+  const QualType ElemQT = getElemType(LHS);
+  const OptPrimType ElemPT = S.getContext().classify(ElemQT);
+
+  if (ElemQT->isIntegerType()) {
+    APInt FirstElem;
+    INT_TYPE_SWITCH_NO_BOOL(*ElemPT,
+                            { FirstElem = LHS.elem<T>(0).toAPSInt(); });
+    const unsigned LaneWidth = FirstElem.getBitWidth();
+
+    APInt AWide(LaneWidth * SourceLen, 0);
+    APInt BWide(LaneWidth * SourceLen, 0);
+
+    for (unsigned I = 0; I != SourceLen; ++I) {
+      APInt ALane;
+      APInt BLane;
+      INT_TYPE_SWITCH_NO_BOOL(*ElemPT, {
+        ALane = LHS.elem<T>(I).toAPSInt();
+        BLane = RHS.elem<T>(I).toAPSInt();
+      });
+      AWide.insertBits(ALane, I * LaneWidth);
+      BWide.insertBits(BLane, I * LaneWidth);
+    }
+    pushInteger(S, Fn(AWide, BWide) ? 1 : 0, Call->getType());
+    return true;
+  } else if (ElemQT->isFloatingType()) {
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RKSimon wrote:

(style) break if-else chain that always returns

https://github.com/llvm/llvm-project/pull/160428