[llvm] r321257 - [Support] Remove MemoryBuffer::getNewUninitMemBuffer

Pavel Labath via llvm-commits llvm-commits at lists.llvm.org
Thu Dec 21 03:27:21 PST 2017


Author: labath
Date: Thu Dec 21 03:27:21 2017
New Revision: 321257

URL: http://llvm.org/viewvc/llvm-project?rev=321257&view=rev
Log:
[Support] Remove MemoryBuffer::getNewUninitMemBuffer

There is nothing useful that can be done with a read-only uninitialized
buffer without const_casting its contents to initialize it. A better
solution is to obtain a writable buffer
(WritableMemoryBuffer::getNewUninitMemBuffer), and then convert it to a
read-only buffer after initialization. All callers of this function have
already been updated to do this, so this function is now unused.

Modified:
    llvm/trunk/include/llvm/Support/MemoryBuffer.h
    llvm/trunk/lib/Support/MemoryBuffer.cpp
    llvm/trunk/unittests/Support/MemoryBufferTest.cpp

Modified: llvm/trunk/include/llvm/Support/MemoryBuffer.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/MemoryBuffer.h?rev=321257&r1=321256&r2=321257&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/MemoryBuffer.h (original)
+++ llvm/trunk/include/llvm/Support/MemoryBuffer.h Thu Dec 21 03:27:21 2017
@@ -123,15 +123,6 @@ public:
   static std::unique_ptr<MemoryBuffer>
   getNewMemBuffer(size_t Size, StringRef BufferName = "");
 
-  /// Allocate a new MemoryBuffer of the specified size that is not initialized.
-  /// Note that the caller should initialize the memory allocated by this
-  /// method. The memory is owned by the MemoryBuffer object.
-  //
-  // TODO: Remove this and migrate callers to
-  //   WritableMemoryBuffer::getNewUninitMemBuffer
-  static std::unique_ptr<MemoryBuffer>
-  getNewUninitMemBuffer(size_t Size, const Twine &BufferName = "");
-
   /// Read all of stdin into a file buffer, and return it.
   static ErrorOr<std::unique_ptr<MemoryBuffer>> getSTDIN();
 
@@ -199,6 +190,9 @@ public:
   getFileSlice(const Twine &Filename, uint64_t MapSize, uint64_t Offset,
                bool IsVolatile = false);
 
+  /// Allocate a new MemoryBuffer of the specified size that is not initialized.
+  /// Note that the caller should initialize the memory allocated by this
+  /// method. The memory is owned by the MemoryBuffer object.
   static std::unique_ptr<WritableMemoryBuffer>
   getNewUninitMemBuffer(size_t Size, const Twine &BufferName = "");
 

Modified: llvm/trunk/lib/Support/MemoryBuffer.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Support/MemoryBuffer.cpp?rev=321257&r1=321256&r2=321257&view=diff
==============================================================================
--- llvm/trunk/lib/Support/MemoryBuffer.cpp (original)
+++ llvm/trunk/lib/Support/MemoryBuffer.cpp Thu Dec 21 03:27:21 2017
@@ -140,17 +140,12 @@ MemoryBuffer::getMemBufferCopy(StringRef
 }
 
 std::unique_ptr<MemoryBuffer>
-MemoryBuffer::getNewUninitMemBuffer(size_t Size, const Twine &BufferName) {
-  return WritableMemoryBuffer::getNewUninitMemBuffer(Size, BufferName);
-}
-
-std::unique_ptr<MemoryBuffer>
 MemoryBuffer::getNewMemBuffer(size_t Size, StringRef BufferName) {
-  std::unique_ptr<MemoryBuffer> SB = getNewUninitMemBuffer(Size, BufferName);
+  auto SB = WritableMemoryBuffer::getNewUninitMemBuffer(Size, BufferName);
   if (!SB)
     return nullptr;
-  memset(const_cast<char*>(SB->getBufferStart()), 0, Size);
-  return SB;
+  memset(SB->getBufferStart(), 0, Size);
+  return std::move(SB);
 }
 
 ErrorOr<std::unique_ptr<MemoryBuffer>>

Modified: llvm/trunk/unittests/Support/MemoryBufferTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Support/MemoryBufferTest.cpp?rev=321257&r1=321256&r2=321257&view=diff
==============================================================================
--- llvm/trunk/unittests/Support/MemoryBufferTest.cpp (original)
+++ llvm/trunk/unittests/Support/MemoryBufferTest.cpp Thu Dec 21 03:27:21 2017
@@ -104,15 +104,15 @@ TEST_F(MemoryBufferTest, copy) {
 
 TEST_F(MemoryBufferTest, make_new) {
   // 0-sized buffer
-  OwningBuffer Zero(MemoryBuffer::getNewUninitMemBuffer(0));
+  OwningBuffer Zero(WritableMemoryBuffer::getNewUninitMemBuffer(0));
   EXPECT_TRUE(nullptr != Zero.get());
 
   // uninitialized buffer with no name
-  OwningBuffer One(MemoryBuffer::getNewUninitMemBuffer(321));
+  OwningBuffer One(WritableMemoryBuffer::getNewUninitMemBuffer(321));
   EXPECT_TRUE(nullptr != One.get());
 
   // uninitialized buffer with name
-  OwningBuffer Two(MemoryBuffer::getNewUninitMemBuffer(123, "bla"));
+  OwningBuffer Two(WritableMemoryBuffer::getNewUninitMemBuffer(123, "bla"));
   EXPECT_TRUE(nullptr != Two.get());
 
   // 0-initialized buffer with no name




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