C# BlobBuilder.WriteSByte方法代码示例

        private static void WriteFakeILWithBranches(BlobBuilder builder, ControlFlowBuilder branchBuilder, int size)
        {
            Assert.Equal(0, builder.Count);

            const byte filling = 0x01;
            int ilOffset = 0;
            foreach (var branch in branchBuilder.Branches)
            {
                builder.WriteBytes(filling, branch.ILOffset - ilOffset);

                Assert.Equal(branch.ILOffset, builder.Count);
                builder.WriteByte((byte)branch.OpCode);

                int operandSize = branch.OpCode.GetBranchOperandSize();
                if (operandSize == 1)
                {
                    builder.WriteSByte(-1);
                }
                else
                {
                    builder.WriteInt32(-1);
                }

                ilOffset = branch.ILOffset + sizeof(byte) + operandSize;
            }

            builder.WriteBytes(filling, size - ilOffset);
            Assert.Equal(size, builder.Count);
        }

        internal void FixupBranches(BlobBuilder srcBuilder, BlobBuilder dstBuilder)
        {
            int srcOffset = 0;
            var branch = _branches[0];
            int branchIndex = 0;
            int blobOffset = 0;
            foreach (Blob blob in srcBuilder.GetBlobs())
            {
                Debug.Assert(blobOffset == 0 || blobOffset == 1 && blob.Buffer[blobOffset - 1] == 0xff);

                while (true)
                {
                    // copy bytes preceding the next branch, or till the end of the blob:
                    int chunkSize = Math.Min(branch.ILOffset - srcOffset, blob.Length - blobOffset);
                    dstBuilder.WriteBytes(blob.Buffer, blobOffset, chunkSize);
                    srcOffset += chunkSize;
                    blobOffset += chunkSize;

                    // there is no branch left in the blob:
                    if (blobOffset == blob.Length)
                    {
                        blobOffset = 0;
                        break;
                    }

                    Debug.Assert(blob.Buffer[blobOffset] == branch.ShortOpCode && (blobOffset + 1 == blob.Length || blob.Buffer[blobOffset + 1] == 0xff));
                    srcOffset += sizeof(byte) + sizeof(sbyte);

                    // write actual branch instruction:
                    int branchDistance;
                    if (branch.IsShortBranchDistance(_labels, out branchDistance))
                    {
                        dstBuilder.WriteByte(branch.ShortOpCode);
                        dstBuilder.WriteSByte((sbyte)branchDistance);
                    }
                    else
                    {
                        dstBuilder.WriteByte((byte)((ILOpCode)branch.ShortOpCode).GetLongBranch());
                        dstBuilder.WriteInt32(branchDistance);
                    }

                    // next branch:
                    branchIndex++;
                    if (branchIndex == _branches.Count)
                    {
                        branch = new BranchInfo(int.MaxValue, default(LabelHandle), 0);
                    }
                    else
                    {
                        branch = _branches[branchIndex];
                    }

                    // the branch starts at the very end and its operand is in the next blob:
                    if (blobOffset == blob.Length - 1)
                    {
                        blobOffset = 1;
                        break;
                    }

                    // skip fake branch instruction:
                    blobOffset += sizeof(byte) + sizeof(sbyte);
                }
            }
        }

        internal static void WriteConstant(BlobBuilder writer, object value)
        {
            if (value == null)
            {
                // The encoding of Type for the nullref value for FieldInit is ELEMENT_TYPE_CLASS with a Value of a 32-bit.
                writer.WriteUInt32(0);
                return;
            }

            var type = value.GetType();
            if (type.GetTypeInfo().IsEnum)
            {
                type = Enum.GetUnderlyingType(type);
            }

            if (type == typeof(bool))
            {
                writer.WriteBoolean((bool)value);
            }
            else if (type == typeof(int))
            {
                writer.WriteInt32((int)value);
            }
            else if (type == typeof(string))
            {
                writer.WriteUTF16((string)value);
            }
            else if (type == typeof(byte))
            {
                writer.WriteByte((byte)value);
            }
            else if (type == typeof(char))
            {
                writer.WriteUInt16((char)value);
            }
            else if (type == typeof(double))
            {
                writer.WriteDouble((double)value);
            }
            else if (type == typeof(short))
            {
                writer.WriteInt16((short)value);
            }
            else if (type == typeof(long))
            {
                writer.WriteInt64((long)value);
            }
            else if (type == typeof(sbyte))
            {
                writer.WriteSByte((sbyte)value);
            }
            else if (type == typeof(float))
            {
                writer.WriteSingle((float)value);
            }
            else if (type == typeof(ushort))
            {
                writer.WriteUInt16((ushort)value);
            }
            else if (type == typeof(uint))
            {
                writer.WriteUInt32((uint)value);
            }
            else if (type == typeof(ulong))
            {
                writer.WriteUInt64((ulong)value);
            }
            else
            {
                // TODO: message
                throw new ArgumentException();
            }
        }

        public void WritePrimitive()
        {
            var writer = new BlobBuilder(17);

            writer.WriteUInt32(0x11223344);
            writer.WriteUInt16(0x5566);
            writer.WriteByte(0x77);
            writer.WriteUInt64(0x8899aabbccddeeff);
            writer.WriteInt32(-1);
            writer.WriteInt16(-2);
            writer.WriteSByte(-3);
            writer.WriteBoolean(true);
            writer.WriteBoolean(false);
            writer.WriteInt64(unchecked((long)0xfedcba0987654321));
            writer.WriteDateTime(new DateTime(0x1112223334445556));
            writer.WriteDecimal(102030405060.70m);
            writer.WriteDouble(double.NaN);
            writer.WriteSingle(float.NegativeInfinity);

            var guid = new Guid("01020304-0506-0708-090A-0B0C0D0E0F10");
            writer.WriteBytes(guid.ToByteArray());
            writer.WriteGuid(guid);

            AssertEx.Equal(new byte[]
            {
                0x44, 0x33, 0x22, 0x11,
                0x66, 0x55,
                0x77,
                0xff, 0xee, 0xdd, 0xcc, 0xbb, 0xaa, 0x99, 0x88,
                0xff, 0xff, 0xff, 0xff,
                0xfe, 0xff,
                0xfd,
                0x01,
                0x00,
                0x21, 0x43, 0x65, 0x87, 0x09, 0xBA, 0xDC, 0xFE,
                0x56, 0x55, 0x44, 0x34, 0x33, 0x22, 0x12, 0x11,
                0x02, 0xD6, 0xE0, 0x9A, 0x94, 0x47, 0x09, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
                0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xF8, 0xFF,
                0x00, 0x00, 0x80, 0xFF,
                0x04, 0x03, 0x02, 0x01, 0x06, 0x05, 0x08, 0x07, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10,
                0x04, 0x03, 0x02, 0x01, 0x06, 0x05, 0x08, 0x07, 0x09, 0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F, 0x10
            }, writer.ToArray());
        }

        /// <exception cref="InvalidOperationException" />
        internal void CopyCodeAndFixupBranches(BlobBuilder srcBuilder, BlobBuilder dstBuilder)
        {
            var branch = _branches[0];
            int branchIndex = 0;

            // offset within the source builder
            int srcOffset = 0;
            
            // current offset within the current source blob
            int srcBlobOffset = 0;

            foreach (Blob srcBlob in srcBuilder.GetBlobs())
            {
                Debug.Assert(
                    srcBlobOffset == 0 || 
                    srcBlobOffset == 1 && srcBlob.Buffer[0] == 0xff ||
                    srcBlobOffset == 4 && srcBlob.Buffer[0] == 0xff && srcBlob.Buffer[1] == 0xff && srcBlob.Buffer[2] == 0xff && srcBlob.Buffer[3] == 0xff);

                while (true)
                {
                    // copy bytes preceding the next branch, or till the end of the blob:
                    int chunkSize = Math.Min(branch.ILOffset - srcOffset, srcBlob.Length - srcBlobOffset);
                    dstBuilder.WriteBytes(srcBlob.Buffer, srcBlobOffset, chunkSize);
                    srcOffset += chunkSize;
                    srcBlobOffset += chunkSize;

                    // there is no branch left in the blob:
                    if (srcBlobOffset == srcBlob.Length)
                    {
                        srcBlobOffset = 0;
                        break;
                    }

                    Debug.Assert(srcBlob.Buffer[srcBlobOffset] == (byte)branch.OpCode);

                    int operandSize = branch.OpCode.GetBranchOperandSize();
                    bool isShortInstruction = operandSize == 1;

                    // Note: the 4B operand is contiguous since we wrote it via BlobBuilder.WriteInt32()
                    Debug.Assert(
                        srcBlobOffset + 1 == srcBlob.Length || 
                        (isShortInstruction ? 
                           srcBlob.Buffer[srcBlobOffset + 1] == 0xff :
                           BitConverter.ToUInt32(srcBlob.Buffer, srcBlobOffset + 1) == 0xffffffff));

                    // write branch opcode:
                    dstBuilder.WriteByte(srcBlob.Buffer[srcBlobOffset]);

                    // write branch operand:
                    int branchDistance;
                    bool isShortDistance = branch.IsShortBranchDistance(_labels, out branchDistance);

                    if (isShortInstruction && !isShortDistance)
                    {
                        // We could potentially implement algortihm that automatically fixes up the branch instructions as well to accomodate bigger distances,
                        // however an optimal algorithm would be rather complex (something like: calculate topological ordering of crossing branch instructions 
                        // and then use fixed point to eliminate cycles). If the caller doesn't care about optimal IL size they can use long branches whenever the 
                        // distance is unknown upfront. If they do they probably already implement more sophisticad algorithm for IL layout optimization already. 
                        throw new InvalidOperationException(SR.Format(SR.DistanceBetweenInstructionAndLabelTooBig, branch.OpCode, srcOffset, branchDistance));
                    }

                    if (isShortInstruction)
                    {
                        dstBuilder.WriteSByte((sbyte)branchDistance);
                    }
                    else
                    {
                        dstBuilder.WriteInt32(branchDistance);
                    }

                    srcOffset += sizeof(byte) + operandSize;

                    // next branch:
                    branchIndex++;
                    if (branchIndex == _branches.Count)
                    {
                        branch = new BranchInfo(int.MaxValue, default(LabelHandle), 0);
                    }
                    else
                    {
                        branch = _branches[branchIndex];
                    }

                    // the branch starts at the very end and its operand is in the next blob:
                    if (srcBlobOffset == srcBlob.Length - 1)
                    {
                        srcBlobOffset = operandSize;
                        break;
                    }

                    // skip fake branch instruction:
                    srcBlobOffset += sizeof(byte) + operandSize;
                }
            }
        }