TableGen: Resolve references when setting value

[arsenm]

Summary

If a record field was used as a template argument,
it wasn't fully evaluated leaving unfolded !ifs.

Fixes bug 30254 reduced testcase as reported.
Unfortunately, tablegen still errors when I remove
the workaround for this bug in the AMDGPU td files
so this might be incomplete.

[arsenm]

ping

[arsenm]

ping

lib/TableGen/TGParser.cpp

if (!BitList.empty()) {
 
     for (unsigned i = 0, e = CurVal->getNumBits(); i != e; ++i)
       if (!NewBits[i])
         NewBits[i] = CurVal->getBit(i);
 
     V = BitsInit::get(NewBits);
   }
 
+  if (!CurMultiClass)
+    V = V->resolveReferences(*CurRec, RV);
+
   if (RV->setValue(V)) {
     std::string InitType;
     if (BitsInit *BI = dyn_cast<BitsInit>(V))
       InitType = (Twine("' of type bit initializer with length ") +
                   Twine(BI->getNumBits())).str();
     return Error(Loc, "Value '" + ValName->getAsUnquotedString() +
                  "' of type '" + RV->getType()->getAsString() +
                  "' is incompatible with initializer '" + V->getAsString() +

test/TableGen/bug30254.td

+// RUN: llvm-tblgen %s | FileCheck %s
+// XFAIL: vg_leak
+
+class Operand {}
+
+def Enum : Operand {
+  int AAA = 1;
+  int BBB = 2;
+}
+
+// CHECK: class getString
+// CHECK-NEXT: string ret = !if(!eq(getString:Selector, 1), "AAA", !if(!eq(getString:Selector, 2), "BBB", ""));
+class getString<int Selector> {
+  string ret =
+    !if(!eq(Selector, Enum.AAA),  "AAA",
+    !if(!eq(Selector, Enum.BBB),  "BBB",
+    ""));
+}
+
+
+class S <int Selector, int SelectorCopy = Selector> {
+  string v1 = getString<Selector>.ret;  // <-- Doesnt resolve!
+  string v2 = getString<SelectorCopy>.ret; // <-- but this resolve!
+}
+
+// Works ok
+
+// CHECK: def C1 {
+// CHECK: int S:SelectorCopy = 1;
+// CHECK: string v1 = "AAA";
+// CHECK: string v2 = "AAA";
+def C1 : S <1>;
+
+// CHECK: def C2 {
+// CHECK: int S:SelectorCopy = 2;
+// CHECK: string v1 = "BBB";
+// CHECK: string v2 = "BBB";
+def C2 : S <2>;
+
+// Incorrect version, S:v1 doesnt resolve to a string
+
+// CHECK: def W1 {
+// CHECK: string v1 = "AAA";
+// CHECK: string v2 = "AAA";
+def W1 : S <Enum.AAA>;
+
+// CHECK: def W2 {
+// CHECK: string v1 = "BBB";
+// CHECK: string v2 = "BBB";
+def W2 : S <Enum.BBB>;