From 4fb96e5105cec4a3eb19a2b7997600b086bac32f Mon Sep 17 00:00:00 2001 From: Xingbo Jiang Date: Mon, 20 Aug 2018 23:13:31 -0700 Subject: [PATCH] [SPARK-25114][CORE] Fix RecordBinaryComparator when subtraction between two words is divisible by Integer.MAX_VALUE. ## What changes were proposed in this pull request? https://github.com/apache/spark/pull/22079#discussion_r209705612 It is possible for two objects to be unequal and yet we consider them as equal with this code, if the long values are separated by Int.MaxValue. This PR fixes the issue. ## How was this patch tested? Add new test cases in `RecordBinaryComparatorSuite`. Closes #22101 from jiangxb1987/fix-rbc. Authored-by: Xingbo Jiang Signed-off-by: Xiao Li --- .../sql/execution/RecordBinaryComparator.java | 26 ++++---- .../sort/RecordBinaryComparatorSuite.java | 66 +++++++++++++++++++ 2 files changed, 81 insertions(+), 11 deletions(-) diff --git a/sql/catalyst/src/main/java/org/apache/spark/sql/execution/RecordBinaryComparator.java b/sql/catalyst/src/main/java/org/apache/spark/sql/execution/RecordBinaryComparator.java index bb77b5bf6de2a..40c2cc806e87a 100644 --- a/sql/catalyst/src/main/java/org/apache/spark/sql/execution/RecordBinaryComparator.java +++ b/sql/catalyst/src/main/java/org/apache/spark/sql/execution/RecordBinaryComparator.java @@ -22,12 +22,10 @@ public final class RecordBinaryComparator extends RecordComparator { - // TODO(jiangxb) Add test suite for this. @Override public int compare( Object leftObj, long leftOff, int leftLen, Object rightObj, long rightOff, int rightLen) { int i = 0; - int res = 0; // If the arrays have different length, the longer one is larger. if (leftLen != rightLen) { @@ -40,27 +38,33 @@ public int compare( // check if stars align and we can get both offsets to be aligned if ((leftOff % 8) == (rightOff % 8)) { while ((leftOff + i) % 8 != 0 && i < leftLen) { - res = (Platform.getByte(leftObj, leftOff + i) & 0xff) - - (Platform.getByte(rightObj, rightOff + i) & 0xff); - if (res != 0) return res; + final int v1 = Platform.getByte(leftObj, leftOff + i) & 0xff; + final int v2 = Platform.getByte(rightObj, rightOff + i) & 0xff; + if (v1 != v2) { + return v1 > v2 ? 1 : -1; + } i += 1; } } // for architectures that support unaligned accesses, chew it up 8 bytes at a time if (Platform.unaligned() || (((leftOff + i) % 8 == 0) && ((rightOff + i) % 8 == 0))) { while (i <= leftLen - 8) { - res = (int) ((Platform.getLong(leftObj, leftOff + i) - - Platform.getLong(rightObj, rightOff + i)) % Integer.MAX_VALUE); - if (res != 0) return res; + final long v1 = Platform.getLong(leftObj, leftOff + i); + final long v2 = Platform.getLong(rightObj, rightOff + i); + if (v1 != v2) { + return v1 > v2 ? 1 : -1; + } i += 8; } } // this will finish off the unaligned comparisons, or do the entire aligned comparison // whichever is needed. while (i < leftLen) { - res = (Platform.getByte(leftObj, leftOff + i) & 0xff) - - (Platform.getByte(rightObj, rightOff + i) & 0xff); - if (res != 0) return res; + final int v1 = Platform.getByte(leftObj, leftOff + i) & 0xff; + final int v2 = Platform.getByte(rightObj, rightOff + i) & 0xff; + if (v1 != v2) { + return v1 > v2 ? 1 : -1; + } i += 1; } diff --git a/sql/core/src/test/java/test/org/apache/spark/sql/execution/sort/RecordBinaryComparatorSuite.java b/sql/core/src/test/java/test/org/apache/spark/sql/execution/sort/RecordBinaryComparatorSuite.java index a19ddbdbadba2..97f3dc588ecc5 100644 --- a/sql/core/src/test/java/test/org/apache/spark/sql/execution/sort/RecordBinaryComparatorSuite.java +++ b/sql/core/src/test/java/test/org/apache/spark/sql/execution/sort/RecordBinaryComparatorSuite.java @@ -253,4 +253,70 @@ public void testBinaryComparatorForNullColumns() throws Exception { assert(compare(0, 0) == 0); assert(compare(0, 1) > 0); } + + @Test + public void testBinaryComparatorWhenSubtractionIsDivisibleByMaxIntValue() throws Exception { + int numFields = 1; + + UnsafeRow row1 = new UnsafeRow(numFields); + byte[] data1 = new byte[100]; + row1.pointTo(data1, computeSizeInBytes(numFields * 8)); + row1.setLong(0, 11); + + UnsafeRow row2 = new UnsafeRow(numFields); + byte[] data2 = new byte[100]; + row2.pointTo(data2, computeSizeInBytes(numFields * 8)); + row2.setLong(0, 11L + Integer.MAX_VALUE); + + insertRow(row1); + insertRow(row2); + + assert(compare(0, 1) < 0); + } + + @Test + public void testBinaryComparatorWhenSubtractionCanOverflowLongValue() throws Exception { + int numFields = 1; + + UnsafeRow row1 = new UnsafeRow(numFields); + byte[] data1 = new byte[100]; + row1.pointTo(data1, computeSizeInBytes(numFields * 8)); + row1.setLong(0, Long.MIN_VALUE); + + UnsafeRow row2 = new UnsafeRow(numFields); + byte[] data2 = new byte[100]; + row2.pointTo(data2, computeSizeInBytes(numFields * 8)); + row2.setLong(0, 1); + + insertRow(row1); + insertRow(row2); + + assert(compare(0, 1) < 0); + } + + @Test + public void testBinaryComparatorWhenOnlyTheLastColumnDiffers() throws Exception { + int numFields = 4; + + UnsafeRow row1 = new UnsafeRow(numFields); + byte[] data1 = new byte[100]; + row1.pointTo(data1, computeSizeInBytes(numFields * 8)); + row1.setInt(0, 11); + row1.setDouble(1, 3.14); + row1.setInt(2, -1); + row1.setLong(3, 0); + + UnsafeRow row2 = new UnsafeRow(numFields); + byte[] data2 = new byte[100]; + row2.pointTo(data2, computeSizeInBytes(numFields * 8)); + row2.setInt(0, 11); + row2.setDouble(1, 3.14); + row2.setInt(2, -1); + row2.setLong(3, 1); + + insertRow(row1); + insertRow(row2); + + assert(compare(0, 1) < 0); + } }