public static void GetIndexOfFirstNonAsciiByte_Boundaries()
{
// The purpose of this test is to make sure we're hitting all of the vectorized
// and draining logic correctly both in the SSE2 and in the non-SSE2 enlightened
// code paths. We shouldn't be reading beyond the boundaries we were given.
// The 5 * Vector test should make sure that we're exercising all possible
// code paths across both implementations.
using (BoundedMemory <byte> mem = BoundedMemory.Allocate <byte>(5 * Vector <byte> .Count))
{
Span <byte> bytes = mem.Span;
// First, try it with all-ASCII buffers.
for (int i = 0; i < bytes.Length; i++)
{
bytes[i] &= 0x7F; // make sure each byte (of the pre-populated random data) is ASCII
}
for (int i = bytes.Length; i >= 0; i--)
{
Assert.Equal(i, CallGetIndexOfFirstNonAsciiByte(bytes.Slice(0, i)));
}
// Then, try it with non-ASCII bytes.
for (int i = bytes.Length; i >= 1; i--)
{
bytes[i - 1] = 0x80; // set non-ASCII
Assert.Equal(i - 1, CallGetIndexOfFirstNonAsciiByte(bytes.Slice(0, i)));
}
}
}
public static void GetIndexOfFirstNonAsciiChar_Vector128InnerLoop()
{
// The purpose of this test is to make sure we're identifying the correct
// vector (of the two that we're reading simultaneously) when performing
// the final ASCII drain at the end of the method once we've broken out
// of the inner loop.
//
// Use U+0123 instead of U+0080 for this test because if our implementation
// uses pminuw / pmovmskb incorrectly, U+0123 will incorrectly show up as ASCII,
// causing our test to produce a false negative.
using (BoundedMemory <char> mem = BoundedMemory.Allocate <char>(1024))
{
Span <char> chars = mem.Span;
for (int i = 0; i < chars.Length; i++)
{
chars[i] &= '\u007F'; // make sure each char (of the pre-populated random data) is ASCII
}
// Two vectors have offsets 0 .. 31. We'll go backward to avoid having to
// re-clear the vector every time.
for (int i = 2 * SizeOfVector128 - 1; i >= 0; i--)
{
chars[100 + i * 13] = '\u0123'; // 13 is relatively prime to 32, so it ensures all possible positions are hit
Assert.Equal(100 + i * 13, CallGetIndexOfFirstNonAsciiChar(chars));
}
}
}
public static void GetIndexOfFirstNonAsciiByte_Vector128InnerLoop()
{
// The purpose of this test is to make sure we're identifying the correct
// vector (of the two that we're reading simultaneously) when performing
// the final ASCII drain at the end of the method once we've broken out
// of the inner loop.
using (BoundedMemory <byte> mem = BoundedMemory.Allocate <byte>(1024))
{
Span <byte> bytes = mem.Span;
for (int i = 0; i < bytes.Length; i++)
{
bytes[i] &= 0x7F; // make sure each byte (of the pre-populated random data) is ASCII
}
// Two vectors have offsets 0 .. 31. We'll go backward to avoid having to
// re-clear the vector every time.
for (int i = 2 * SizeOfVector128 - 1; i >= 0; i--)
{
bytes[100 + i * 13] = 0x80; // 13 is relatively prime to 32, so it ensures all possible positions are hit
Assert.Equal(100 + i * 13, CallGetIndexOfFirstNonAsciiByte(bytes));
}
}
}
public static void NarrowUtf16ToAscii_SomeNonAsciiInput()
{
using BoundedMemory <char> utf16Mem = BoundedMemory.Allocate <char>(128);
using BoundedMemory <byte> asciiMem = BoundedMemory.Allocate <byte>(128);
// Fill source with 00 .. 7F.
Span <char> utf16Span = utf16Mem.Span;
for (int i = 0; i < utf16Span.Length; i++)
{
utf16Span[i] = (char)i;
}
// We'll write to the ASCII span.
Span <byte> asciiSpan = asciiMem.Span;
for (int i = utf16Span.Length - 1; i >= 0; i--)
{
RandomNumberGenerator.Fill(asciiSpan); // fill with garbage
// First, keep track of the garbage we wrote to the destination.
// We want to ensure it wasn't overwritten.
byte[] expectedTrailingData = asciiSpan.Slice(i).ToArray();
// Then, set the desired byte as non-ASCII, then check that the workhorse
// correctly saw the data as non-ASCII.
utf16Span[i] = '\u0123'; // use U+0123 instead of U+0080 since it catches inappropriate pmovmskb usage
Assert.Equal(i, CallNarrowUtf16ToAscii(utf16Span, asciiSpan));
// Next, validate that the ASCII data was transcoded properly.
for (int j = 0; j < i; j++)
{
Assert.Equal((ushort)utf16Span[j], (ushort)asciiSpan[j]);
}
// Finally, validate that the trailing data wasn't overwritten with non-ASCII data.
Assert.Equal(expectedTrailingData, asciiSpan.Slice(i).ToArray());
}
}
public static void WidenAsciiToUtf16_SomeNonAsciiInput()
{
using BoundedMemory <byte> asciiMem = BoundedMemory.Allocate <byte>(128);
using BoundedMemory <char> utf16Mem = BoundedMemory.Allocate <char>(128);
// Fill source with 00 .. 7F, then trap future writes.
Span <byte> asciiSpan = asciiMem.Span;
for (int i = 0; i < asciiSpan.Length; i++)
{
asciiSpan[i] = (byte)i;
}
// We'll write to the UTF-16 span.
Span <char> utf16Span = utf16Mem.Span;
for (int i = asciiSpan.Length - 1; i >= 0; i--)
{
RandomNumberGenerator.Fill(MemoryMarshal.Cast <char, byte>(utf16Span)); // fill with garbage
// First, keep track of the garbage we wrote to the destination.
// We want to ensure it wasn't overwritten.
char[] expectedTrailingData = utf16Span.Slice(i).ToArray();
// Then, set the desired byte as non-ASCII, then check that the workhorse
// correctly saw the data as non-ASCII.
asciiSpan[i] |= (byte)0x80;
Assert.Equal(i, CallWidenAsciiToUtf16(asciiSpan, utf16Span));
// Next, validate that the ASCII data was transcoded properly.
for (int j = 0; j < i; j++)
{
Assert.Equal((ushort)asciiSpan[j], (ushort)utf16Span[j]);
}
// Finally, validate that the trailing data wasn't overwritten with non-ASCII data.
Assert.Equal(expectedTrailingData, utf16Span.Slice(i).ToArray());
}
}
private static unsafe void GetIndexOfFirstInvalidUtf8Sequence_Test_Core(byte[] input, int expectedRetVal, int expectedRuneCount, int expectedSurrogatePairCount)
{
// Arrange
using BoundedMemory <byte> boundedMemory = BoundedMemory.AllocateFromExistingData(input);
boundedMemory.MakeReadonly();
// Act
int actualRetVal;
int actualSurrogatePairCount;
int actualRuneCount;
fixed(byte *pInputBuffer = &MemoryMarshal.GetReference(boundedMemory.Span))
{
byte *pFirstInvalidByte = Utf8Utility.GetPointerToFirstInvalidByte(pInputBuffer, input.Length, out int utf16CodeUnitCountAdjustment, out int scalarCountAdjustment);
long ptrDiff = pFirstInvalidByte - pInputBuffer;
Assert.True((ulong)ptrDiff <= (uint)input.Length, "ptrDiff was outside expected range.");
Assert.True(utf16CodeUnitCountAdjustment <= 0, "UTF-16 code unit count adjustment must be 0 or negative.");
Assert.True(scalarCountAdjustment <= 0, "Scalar count adjustment must be 0 or negative.");
actualRetVal = (ptrDiff == input.Length) ? -1 : (int)ptrDiff;
// The last two 'out' parameters are:
// a) The number to be added to the "bytes processed" return value to come up with the total UTF-16 code unit count, and
// b) The number to be added to the "total UTF-16 code unit count" value to come up with the total scalar count.
int totalUtf16CodeUnitCount = (int)ptrDiff + utf16CodeUnitCountAdjustment;
actualRuneCount = totalUtf16CodeUnitCount + scalarCountAdjustment;
// Surrogate pair count is number of UTF-16 code units less the number of scalars.
actualSurrogatePairCount = totalUtf16CodeUnitCount - actualRuneCount;
}
// Assert
Assert.Equal(expectedRetVal, actualRetVal);
Assert.Equal(expectedRuneCount, actualRuneCount);
Assert.Equal(expectedSurrogatePairCount, actualSurrogatePairCount);
}
public static void GetIndexOfFirstNonAsciiChar_Boundaries()
{
// The purpose of this test is to make sure we're hitting all of the vectorized
// and draining logic correctly both in the SSE2 and in the non-SSE2 enlightened
// code paths. We shouldn't be reading beyond the boundaries we were given.
//
// The 5 * Vector test should make sure that we're exercising all possible
// code paths across both implementations. The sizeof(char) is because we're
// specifying element count, but underlying implementation reintepret casts to bytes.
//
// Use U+0123 instead of U+0080 for this test because if our implementation
// uses pminuw / pmovmskb incorrectly, U+0123 will incorrectly show up as ASCII,
// causing our test to produce a false negative.
using (BoundedMemory <char> mem = BoundedMemory.Allocate <char>(5 * Vector <byte> .Count / sizeof(char)))
{
Span <char> chars = mem.Span;
for (int i = 0; i < chars.Length; i++)
{
chars[i] &= '\u007F'; // make sure each char (of the pre-populated random data) is ASCII
}
for (int i = chars.Length; i >= 0; i--)
{
Assert.Equal(i, CallGetIndexOfFirstNonAsciiChar(chars.Slice(0, i)));
}
// Then, try it with non-ASCII bytes.
for (int i = chars.Length; i >= 1; i--)
{
chars[i - 1] = '\u0123'; // set non-ASCII
Assert.Equal(i - 1, CallGetIndexOfFirstNonAsciiChar(chars.Slice(0, i)));
}
}
}
public static void NarrowUtf16ToAscii_AllAsciiInput()
{
using BoundedMemory <char> utf16Mem = BoundedMemory.Allocate <char>(128);
using BoundedMemory <byte> asciiMem = BoundedMemory.Allocate <byte>(128);
// Fill source with 00 .. 7F.
Span <char> utf16Span = utf16Mem.Span;
for (int i = 0; i < utf16Span.Length; i++)
{
utf16Span[i] = (char)i;
}
utf16Mem.MakeReadonly();
// We'll write to the ASCII span.
// We test with a variety of span lengths to test alignment and fallthrough code paths.
Span <byte> asciiSpan = asciiMem.Span;
for (int i = 0; i < utf16Span.Length; i++)
{
asciiSpan.Clear(); // remove any data from previous iteration
// First, validate that the workhorse saw the incoming data as all-ASCII.
Assert.Equal(128 - i, CallNarrowUtf16ToAscii(utf16Span.Slice(i), asciiSpan.Slice(i)));
// Then, validate that the data was transcoded properly.
for (int j = i; j < 128; j++)
{
Assert.Equal((ushort)utf16Span[i], (ushort)asciiSpan[i]);
}
}
}