[llvm] [ObjectYAML][NFC] Hoist ContiguousBlobAccumulator into a shared header (PR #207306)

[Haohai Wen via llvm-commits]

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@@ -0,0 +1,72 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file implements the ContiguousBlobAccumulator methods declared in
+/// ContiguousBlobAccumulator.h.
+///
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ObjectYAML/ContiguousBlobAccumulator.h"
+#include "llvm/ObjectYAML/YAML.h"
+#include "llvm/Support/Errc.h"
+#include "llvm/Support/LEB128.h"
+#include "llvm/Support/MathExtras.h"
+#include <cassert>
+#include <cstring>
+
+using namespace llvm;
+using namespace llvm::yaml;
+
+bool ContiguousBlobAccumulator::checkLimit(uint64_t Size) {
+  if (!ReachedLimitErr && getOffset() + Size <= MaxSize)
+    return true;
+  if (!ReachedLimitErr)
+    ReachedLimitErr = createStringError(errc::invalid_argument,
+                                        "reached the output size limit");
+  return false;
+}
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HaohaiWen wrote:

Off must be <= MaxSize.
Just need to be    if (!ReachedLimitErr && Size <= MaxSize - Off)

https://github.com/llvm/llvm-project/pull/207306