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package java.nio;

import jdk.internal.misc.ScopedMemoryAccess;
import jdk.internal.util.ArraysSupport;

Mismatch methods for buffers
/** * Mismatch methods for buffers */
final class BufferMismatch { final static ScopedMemoryAccess SCOPED_MEMORY_ACCESS = ScopedMemoryAccess.getScopedMemoryAccess(); static int mismatch(ByteBuffer a, int aOff, ByteBuffer b, int bOff, int length) { int i = 0; if (length > 7) { if (a.get(aOff) != b.get(bOff)) return 0; i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + aOff, b.base(), b.address + bOff, length, ArraysSupport.LOG2_ARRAY_BYTE_INDEX_SCALE); if (i >= 0) return i; i = length - ~i; } for (; i < length; i++) { if (a.get(aOff + i) != b.get(bOff + i)) return i; } return -1; } static int mismatch(CharBuffer a, int aOff, CharBuffer b, int bOff, int length) { int i = 0; // Ensure only heap or off-heap buffer instances use the // vectorized mismatch. If either buffer is a StringCharBuffer // (order is null) then the slow path is taken if (length > 3 && a.charRegionOrder() == b.charRegionOrder() && a.charRegionOrder() != null && b.charRegionOrder() != null) { if (a.get(aOff) != b.get(bOff)) return 0; i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_CHAR_INDEX_SCALE), b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_CHAR_INDEX_SCALE), length, ArraysSupport.LOG2_ARRAY_CHAR_INDEX_SCALE); if (i >= 0) return i; i = length - ~i; } for (; i < length; i++) { if (a.get(aOff + i) != b.get(bOff + i)) return i; } return -1; } static int mismatch(ShortBuffer a, int aOff, ShortBuffer b, int bOff, int length) { int i = 0; if (length > 3 && a.order() == b.order()) { if (a.get(aOff) != b.get(bOff)) return 0; i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_SHORT_INDEX_SCALE), b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_SHORT_INDEX_SCALE), length, ArraysSupport.LOG2_ARRAY_SHORT_INDEX_SCALE); if (i >= 0) return i; i = length - ~i; } for (; i < length; i++) { if (a.get(aOff + i) != b.get(bOff + i)) return i; } return -1; } static int mismatch(IntBuffer a, int aOff, IntBuffer b, int bOff, int length) { int i = 0; if (length > 1 && a.order() == b.order()) { if (a.get(aOff) != b.get(bOff)) return 0; i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_INT_INDEX_SCALE), b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_INT_INDEX_SCALE), length, ArraysSupport.LOG2_ARRAY_INT_INDEX_SCALE); if (i >= 0) return i; i = length - ~i; } for (; i < length; i++) { if (a.get(aOff + i) != b.get(bOff + i)) return i; } return -1; } static int mismatch(FloatBuffer a, int aOff, FloatBuffer b, int bOff, int length) { int i = 0; if (length > 1 && a.order() == b.order()) { if (Float.floatToRawIntBits(a.get(aOff)) == Float.floatToRawIntBits(b.get(bOff))) { i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_FLOAT_INDEX_SCALE), b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_FLOAT_INDEX_SCALE), length, ArraysSupport.LOG2_ARRAY_FLOAT_INDEX_SCALE); } // Mismatched if (i >= 0) { // Check if mismatch is not associated with two NaN values; and // is not associated with +0 and -0 float av = a.get(aOff + i); float bv = b.get(bOff + i); if (av != bv && (!Float.isNaN(av) || !Float.isNaN(bv))) return i; // Fall back to slow mechanism // ISSUE: Consider looping over vectorizedMismatch adjusting ranges // However, requires that returned value be relative to input ranges i++; } // Matched else { i = length - ~i; } } for (; i < length; i++) { float av = a.get(aOff + i); float bv = b.get(bOff + i); if (av != bv && (!Float.isNaN(av) || !Float.isNaN(bv))) return i; } return -1; } static int mismatch(LongBuffer a, int aOff, LongBuffer b, int bOff, int length) { int i = 0; if (length > 0 && a.order() == b.order()) { if (a.get(aOff) != b.get(bOff)) return 0; i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_LONG_INDEX_SCALE), b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_LONG_INDEX_SCALE), length, ArraysSupport.LOG2_ARRAY_LONG_INDEX_SCALE); return i >= 0 ? i : -1; } for (; i < length; i++) { if (a.get(aOff + i) != b.get(bOff + i)) return i; } return -1; } static int mismatch(DoubleBuffer a, int aOff, DoubleBuffer b, int bOff, int length) { int i = 0; if (length > 0 && a.order() == b.order()) { if (Double.doubleToRawLongBits(a.get(aOff)) == Double.doubleToRawLongBits(b.get(bOff))) { i = SCOPED_MEMORY_ACCESS.vectorizedMismatch(a.scope(), b.scope(), a.base(), a.address + (aOff << ArraysSupport.LOG2_ARRAY_DOUBLE_INDEX_SCALE), b.base(), b.address + (bOff << ArraysSupport.LOG2_ARRAY_DOUBLE_INDEX_SCALE), length, ArraysSupport.LOG2_ARRAY_DOUBLE_INDEX_SCALE); } // Mismatched if (i >= 0) { // Check if mismatch is not associated with two NaN values; and // is not associated with +0 and -0 double av = a.get(aOff + i); double bv = b.get(bOff + i); if (av != bv && (!Double.isNaN(av) || !Double.isNaN(bv))) return i; // Fall back to slow mechanism // ISSUE: Consider looping over vectorizedMismatch adjusting ranges // However, requires that returned value be relative to input ranges i++; } // Matched else { return -1; } } for (; i < length; i++) { double av = a.get(aOff + i); double bv = b.get(bOff + i); if (av != bv && (!Double.isNaN(av) || !Double.isNaN(bv))) return i; } return -1; } }