From 456c9968e51cc015f803cca1063703fbbc6fe958 Mon Sep 17 00:00:00 2001 From: "Duncan P. N. Exon Smith" Date: Sun, 27 Mar 2016 23:00:59 +0000 Subject: Support: Implement StreamingMemoryObject::getPointer The implementation is fairly obvious. This is preparation for using some blobs in bitcode. For clarity (and perhaps future-proofing?), I moved the call to JumpToBit in BitstreamCursor::readRecord ahead of calling MemoryObject::getPointer, since JumpToBit can theoretically (a) read bytes, which (b) invalidates the blob pointer. This isn't strictly necessary the two memory objects we have: - The return of RawMemoryObject::getPointer is valid until the memory object is destroyed. - StreamingMemoryObject::getPointer is valid until the next chunk is read from the stream. Since the JumpToBit call is only going ahead to a word boundary, we'll never load another chunk. However, reordering makes it clear by inspection that the blob returned by BitstreamCursor::readRecord will be valid. I added some tests for StreamingMemoryObject::getPointer and BitstreamCursor::readRecord. llvm-svn: 264549 --- .../Support/StreamingMemoryObjectTest.cpp | 26 ++++++++++++++++++++++ 1 file changed, 26 insertions(+) (limited to 'llvm/unittests/Support/StreamingMemoryObjectTest.cpp') diff --git a/llvm/unittests/Support/StreamingMemoryObjectTest.cpp b/llvm/unittests/Support/StreamingMemoryObjectTest.cpp index 261f2144..836dfa9 100644 --- a/llvm/unittests/Support/StreamingMemoryObjectTest.cpp +++ b/llvm/unittests/Support/StreamingMemoryObjectTest.cpp @@ -24,6 +24,21 @@ class NullDataStreamer : public DataStreamer { } }; +class BufferStreamer : public DataStreamer { + StringRef Buffer; + +public: + BufferStreamer(StringRef Buffer) : Buffer(Buffer) {} + size_t GetBytes(unsigned char *OutBuffer, size_t Length) override { + if (Length >= Buffer.size()) + Length = Buffer.size(); + + std::copy(Buffer.begin(), Buffer.begin() + Length, OutBuffer); + Buffer = Buffer.drop_front(Length); + return Length; + } +}; + TEST(StreamingMemoryObjectTest, isValidAddress) { auto DS = make_unique(); StreamingMemoryObject O(std::move(DS)); @@ -39,4 +54,15 @@ TEST(StreamingMemoryObjectTest, setKnownObjectSize) { EXPECT_EQ(8u, O.readBytes(Buf, 16, 16)); } +TEST(StreamingMemoryObjectTest, getPointer) { + uint8_t InputBuffer[] = {0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07}; + StreamingMemoryObject O(make_unique(StringRef( + reinterpret_cast(InputBuffer), sizeof(InputBuffer)))); + + EXPECT_TRUE(std::equal(InputBuffer + 1, InputBuffer + 2, O.getPointer(1, 2))); + EXPECT_TRUE(std::equal(InputBuffer + 3, InputBuffer + 7, O.getPointer(3, 4))); + EXPECT_TRUE(std::equal(InputBuffer + 4, InputBuffer + 8, O.getPointer(4, 5))); + EXPECT_TRUE(std::equal(InputBuffer, InputBuffer + 8, O.getPointer(0, 20))); +} + } // end namespace -- cgit v1.1