[llvm] TableGen: Split RuntimeLibcallsEmitter into separate utility header (PR #166583)

[Rahul Joshi via llvm-commits]

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@@ -0,0 +1,93 @@
+//===- RuntimeLibcalls.cpp ------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "RuntimeLibcalls.h"
+#include "llvm/TableGen/Error.h"
+
+using namespace llvm;
+
+RuntimeLibcalls::RuntimeLibcalls(const RecordKeeper &Records) {
+  ArrayRef<const Record *> AllRuntimeLibcalls =
+      Records.getAllDerivedDefinitions("RuntimeLibcall");
+
+  RuntimeLibcallDefList.reserve(AllRuntimeLibcalls.size());
+
+  size_t CallTypeEnumVal = 0;
+  for (const Record *RuntimeLibcallDef : AllRuntimeLibcalls) {
+    RuntimeLibcallDefList.emplace_back(RuntimeLibcallDef, CallTypeEnumVal++);
+    Def2RuntimeLibcall[RuntimeLibcallDef] = &RuntimeLibcallDefList.back();
+  }
+
+  for (RuntimeLibcall &LibCall : RuntimeLibcallDefList)
+    Def2RuntimeLibcall[LibCall.getDef()] = &LibCall;
+
+  ArrayRef<const Record *> AllRuntimeLibcallImplsRaw =
+      Records.getAllDerivedDefinitions("RuntimeLibcallImpl");
+
+  SmallVector<const Record *, 1024> AllRuntimeLibcallImpls(
+      AllRuntimeLibcallImplsRaw);
+
+  // Sort by libcall impl name and secondarily by the enum name.
+  sort(AllRuntimeLibcallImpls, [](const Record *A, const Record *B) {
+    return std::pair(A->getValueAsString("LibCallFuncName"), A->getName()) <
+           std::pair(B->getValueAsString("LibCallFuncName"), B->getName());
+  });
+
+  RuntimeLibcallImplDefList.reserve(AllRuntimeLibcallImpls.size());
+
+  size_t LibCallImplEnumVal = 1;
+  for (const Record *LibCallImplDef : AllRuntimeLibcallImpls) {
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jurahul wrote:

nit: use enumerate here?

https://github.com/llvm/llvm-project/pull/166583