[llvm] [IR][Attribute] Add support for intersecting AttributeLists; NFC (PR #109719)

[via llvm-commits]

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@@ -386,4 +389,342 @@ TEST(Attributes, CalleeAttributes) {
   }
 }
 
+TEST(Attributes, SetIntersect) {
+  LLVMContext C0, C1;
+  std::optional<AttributeSet> Res;
+  auto BuildAttr = [&](LLVMContext &C, Attribute::AttrKind Kind, uint64_t Int,
+                       Type *Ty, ConstantRange &CR,
+                       ArrayRef<ConstantRange> CRList) {
+    if (Attribute::isEnumAttrKind(Kind))
+      return Attribute::get(C, Kind);
+    if (Attribute::isTypeAttrKind(Kind))
+      return Attribute::get(C, Kind, Ty);
+    if (Attribute::isIntAttrKind(Kind))
+      return Attribute::get(C, Kind, Int);
+    if (Attribute::isConstantRangeAttrKind(Kind))
+      return Attribute::get(C, Kind, CR);
+    if (Attribute::isConstantRangeListAttrKind(Kind))
+      return Attribute::get(C, Kind, CRList);
+    std::abort();
+  };
+  for (unsigned i = Attribute::AttrKind::None + 1,
+                e = Attribute::AttrKind::EndAttrKinds;
+       i < e; ++i) {
+    Attribute::AttrKind Kind = static_cast<Attribute::AttrKind>(i);
+
+    Attribute::AttrKind Other =
+        Kind == Attribute::NoUndef ? Attribute::NonNull : Attribute::NoUndef;
+    AttributeSet AS0, AS1;
+    AttrBuilder AB0(C0);
+    AttrBuilder AB1(C1);
+    uint64_t V0, V1;
+    V0 = 0;
+    V1 = 0;
+    if (Attribute::intersectWithCustom(Kind)) {
+      switch (Kind) {
+      case Attribute::Alignment:
+        V0 = 2;
+        V1 = 4;
+        break;
+      case Attribute::Memory:
+        V0 = MemoryEffects::readOnly().toIntValue();
+        V1 = MemoryEffects::none().toIntValue();
+        break;
+      case Attribute::NoFPClass:
+        V0 = FPClassTest::fcNan | FPClassTest::fcInf;
+        V1 = FPClassTest::fcNan;
+        break;
+      case Attribute::Range:
+        break;
+      default:
+        ASSERT_FALSE(true);
+      }
+    } else {
+      V0 = (i & 2) + 1;
+      V1 = (2 - (i & 2)) + 1;
+    }
+
+    ConstantRange CR0(APInt(32, 0), APInt(32, 10));
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goldsteinn wrote:

Sorry about that and thank you for the prompt fix.

https://github.com/llvm/llvm-project/pull/109719