[llvm] [RISCV]Add support for resolving encoding conflicts among vendor specific CSRs (PR #96174)

[Craig Topper via llvm-commits]

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@@ -452,55 +461,80 @@ void SearchableTableEmitter::emitLookupFunction(const GenericTable &Table,
   OS << "  auto Idx = std::lower_bound(Table.begin(), Table.end(), Key,\n";
   OS << "    [](const " << IndexTypeName << " &LHS, const KeyType &RHS) {\n";
 
-  for (const auto &Field : Index.Fields) {
-    if (isa<StringRecTy>(Field.RecType)) {
-      OS << "      int Cmp" << Field.Name << " = StringRef(LHS." << Field.Name
-         << ").compare(RHS." << Field.Name << ");\n";
-      OS << "      if (Cmp" << Field.Name << " < 0) return true;\n";
-      OS << "      if (Cmp" << Field.Name << " > 0) return false;\n";
-    } else if (Field.Enum) {
-      // Explicitly cast to unsigned, because the signedness of enums is
-      // compiler-dependent.
-      OS << "      if ((unsigned)LHS." << Field.Name << " < (unsigned)RHS."
-         << Field.Name << ")\n";
-      OS << "        return true;\n";
-      OS << "      if ((unsigned)LHS." << Field.Name << " > (unsigned)RHS."
-         << Field.Name << ")\n";
-      OS << "        return false;\n";
-    } else {
-      OS << "      if (LHS." << Field.Name << " < RHS." << Field.Name << ")\n";
-      OS << "        return true;\n";
-      OS << "      if (LHS." << Field.Name << " > RHS." << Field.Name << ")\n";
-      OS << "        return false;\n";
+  auto emitComparator = [&]() {
+    for (const auto &Field : Index.Fields) {
+      if (isa<StringRecTy>(Field.RecType)) {
+        OS << "      int Cmp" << Field.Name << " = StringRef(LHS." << Field.Name
+           << ").compare(RHS." << Field.Name << ");\n";
+        OS << "      if (Cmp" << Field.Name << " < 0) return true;\n";
+        OS << "      if (Cmp" << Field.Name << " > 0) return false;\n";
+      } else if (Field.Enum) {
+        // Explicitly cast to unsigned, because the signedness of enums is
+        // compiler-dependent.
+        OS << "      if ((unsigned)LHS." << Field.Name << " < (unsigned)RHS."
+           << Field.Name << ")\n";
+        OS << "        return true;\n";
+        OS << "      if ((unsigned)LHS." << Field.Name << " > (unsigned)RHS."
+           << Field.Name << ")\n";
+        OS << "        return false;\n";
+      } else {
+        OS << "      if (LHS." << Field.Name << " < RHS." << Field.Name
+           << ")\n";
+        OS << "        return true;\n";
+        OS << "      if (LHS." << Field.Name << " > RHS." << Field.Name
+           << ")\n";
+        OS << "        return false;\n";
+      }
     }
-  }
 
-  OS << "      return false;\n";
-  OS << "    });\n\n";
+    OS << "      return false;\n";
+    OS << "    });\n\n";
+  };
+  emitComparator();
 
   OS << "  if (Idx == Table.end()";
 
   for (const auto &Field : Index.Fields)
     OS << " ||\n      Key." << Field.Name << " != Idx->" << Field.Name;
-  OS << ")\n    return nullptr;\n";
 
-  if (IsPrimary)
+  if (UseListArg) {
+    OS << ")\n    return;\n\n";
+    OS << "  auto UpperBound = std::upper_bound(Table.begin(), Table.end(), "
+          "Key,\n";
+    OS << "    [](const KeyType &LHS, const " << IndexTypeName << " &RHS) {\n";
+    emitComparator();
+    OS << "  while(Idx != UpperBound){\n";
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topperc wrote:

Need space after `while` and before `{`

https://github.com/llvm/llvm-project/pull/96174