# HG changeset patch
# User Stefan Anzinger <stefan.anzinger@gmail.com>
# Date 1408988516 25200
# Node ID c01648e414100e775ec2855d65f38d17b5612cc1
# Parent  41c00b10bfce4fbdcfe1ef83085a535bd1be016d
[SPARC] Implement UnsafeArrayCopy for aligned memory access

diff -r 41c00b10bfce -r c01648e41410 graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/UnsafeArrayCopySnippets.java
--- a/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/UnsafeArrayCopySnippets.java	Mon Aug 25 10:35:40 2014 -0700
+++ b/graal/com.oracle.graal.hotspot/src/com/oracle/graal/hotspot/replacements/UnsafeArrayCopySnippets.java	Mon Aug 25 10:41:56 2014 -0700
@@ -223,25 +223,48 @@
         int log2ElementSize = (layoutHelper >> layoutHelperLog2ElementSizeShift()) & layoutHelperLog2ElementSizeMask();
         int headerSize = (layoutHelper >> layoutHelperHeaderSizeShift()) & layoutHelperHeaderSizeMask();
 
+        Unsigned vectorSize = Word.unsigned(VECTOR_SIZE);
         Unsigned srcOffset = Word.unsigned(srcPos).shiftLeft(log2ElementSize).add(headerSize);
         Unsigned destOffset = Word.unsigned(destPos).shiftLeft(log2ElementSize).add(headerSize);
         Unsigned destStart = destOffset;
-        Unsigned sizeInBytes = Word.unsigned(length).shiftLeft(log2ElementSize);
         Unsigned destEnd = destOffset.add(Word.unsigned(length).shiftLeft(log2ElementSize));
 
-        Unsigned nonVectorBytes = sizeInBytes.unsignedRemainder(Word.unsigned(VECTOR_SIZE));
+        Unsigned destVectorEnd = null;
+        Unsigned nonVectorBytes = null;
+        Unsigned sizeInBytes = Word.unsigned(length).shiftLeft(log2ElementSize);
+        if (supportsUnalignedMemoryAccess) {
+            nonVectorBytes = sizeInBytes.unsignedRemainder(vectorSize);
+            destVectorEnd = destEnd;
+        } else {
+            boolean inPhase = srcOffset.and((int) VECTOR_SIZE - 1).equal(destOffset.and((int) VECTOR_SIZE - 1));
+            boolean hasAtLeastOneVector = sizeInBytes.aboveOrEqual(vectorSize);
+            // We must have at least one full vector, otherwise we must copy each byte separately
+            if (hasAtLeastOneVector && inPhase) { // If in phase, we can vectorize
+                nonVectorBytes = vectorSize.subtract(destStart.unsignedRemainder(vectorSize));
+            } else { // fallback is byte-wise
+                nonVectorBytes = sizeInBytes;
+            }
+            destVectorEnd = destEnd.subtract(destEnd.unsignedRemainder(vectorSize));
+        }
+
         Unsigned destNonVectorEnd = destStart.add(nonVectorBytes);
-
         while (destOffset.belowThan(destNonVectorEnd)) {
             ObjectAccess.writeByte(dest, destOffset, ObjectAccess.readByte(src, srcOffset, ANY_LOCATION), ANY_LOCATION);
             destOffset = destOffset.add(1);
             srcOffset = srcOffset.add(1);
         }
-        while (destOffset.belowThan(destEnd)) {
+        // Unsigned destVectorEnd = destEnd.subtract(destEnd.unsignedRemainder(8));
+        while (destOffset.belowThan(destVectorEnd)) {
             ObjectAccess.writeWord(dest, destOffset, ObjectAccess.readWord(src, srcOffset, ANY_LOCATION), ANY_LOCATION);
             destOffset = destOffset.add(wordSize());
             srcOffset = srcOffset.add(wordSize());
         }
+        // Do the last bytes each when it is required to have absolute alignment.
+        while (!supportsUnalignedMemoryAccess && destOffset.belowThan(destEnd)) {
+            ObjectAccess.writeByte(dest, destOffset, ObjectAccess.readByte(src, srcOffset, ANY_LOCATION), ANY_LOCATION);
+            destOffset = destOffset.add(1);
+            srcOffset = srcOffset.add(1);
+        }
     }
 
     public static class Templates extends AbstractTemplates {