Damage control array alignment change to COH only

dragonwell-project · Jun 11, 2024 · 3482e5b · 3482e5b
1 parent 0fa2d16
commit 3482e5b
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Showing 6 changed files with 19 additions and 18 deletions.
diff --git a/src/hotspot/share/oops/arrayOop.hpp b/src/hotspot/share/oops/arrayOop.hpp
@@ -96,7 +96,8 @@ class arrayOopDesc : public oopDesc {
   // Returns the offset of the first element.
   static int base_offset_in_bytes(BasicType type) {
     size_t hs = header_size_in_bytes();
-    return (int)(element_type_should_be_aligned(type) ? align_up(hs, BytesPerLong) : hs);
+    // When we are not using UseCompactObjectHeaders, revert back to a more conservative alignment.
+    return (int)((!UseCompactObjectHeaders || element_type_should_be_aligned(type)) ? align_up(hs, BytesPerLong) : hs);
   }
 
   // Returns the address of the first element. The elements in the array will not

diff --git a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/oops/Array.java b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/oops/Array.java
@@ -110,7 +110,7 @@ public long getObjectSize() {
 
   public static long baseOffsetInBytes(BasicType type) {
     long typeSizeInBytes = headerSizeInBytes();
-    if (elementTypeShouldBeAligned(type)) {
+    if (!VM.getVM().isCompactObjectHeadersEnabled() || elementTypeShouldBeAligned(type)) {
       VM vm = VM.getVM();
       return vm.alignUp(typeSizeInBytes, vm.getVM().getHeapWordSize());
     } else {

diff --git a/test/hotspot/gtest/oops/test_arrayOop.cpp b/test/hotspot/gtest/oops/test_arrayOop.cpp
@@ -105,17 +105,17 @@ TEST_VM(arrayOopDesc, base_offset) {
     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT),  16);
     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),   16);
   } else {
-    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BOOLEAN), 20);
-    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BYTE),    20);
-    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_SHORT),   20);
-    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_CHAR),    20);
-    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_INT),     20);
-    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_FLOAT),   20);
+    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BOOLEAN), 24);
+    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_BYTE),    24);
+    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_SHORT),   24);
+    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_CHAR),    24);
+    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_INT),     24);
+    EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_FLOAT),   24);
     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_LONG),    24);
     EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_DOUBLE),  24);
     if (UseCompressedOops) {
-      EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 20);
-      EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  20);
+      EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 24);
+      EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  24);
     } else {
       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_OBJECT), 24);
       EXPECT_EQ(arrayOopDesc::base_offset_in_bytes(T_ARRAY),  24);

diff --git a/test/hotspot/gtest/oops/test_objArrayOop.cpp b/test/hotspot/gtest/oops/test_objArrayOop.cpp
@@ -32,16 +32,16 @@ TEST_VM(objArrayOop, osize) {
   } x[] = {
 //    ObjAligInB, UseCCP, UseCoops, UseCOH, object size in heap words
 #ifdef _LP64
-    { 8,          false,  false,    false,  4 },  // 20 byte header, 8 byte oops
-    { 8,          false,  true,     false,  3 },  // 20 byte header, 4 byte oops
+    { 8,          false,  false,    false,  4 },  // 24 byte header, 8 byte oops
+    { 8,          false,  true,     false,  4 },  // 24 byte header, 4 byte oops
     { 8,          true,   false,    false,  3 },  // 16 byte header, 8 byte oops
     { 8,          true,   true,     false,  3 },  // 16 byte header, 4 byte oops
-    { 16,         false,  false,    false,  4 },  // 20 byte header, 8 byte oops, 16-byte align
-    { 16,         false,  true,     false,  4 },  // 20 byte header, 4 byte oops, 16-byte align
+    { 16,         false,  false,    false,  4 },  // 24 byte header, 8 byte oops, 16-byte align
+    { 16,         false,  true,     false,  4 },  // 24 byte header, 4 byte oops, 16-byte align
     { 16,         true,   false,    false,  4 },  // 16 byte header, 8 byte oops, 16-byte align
     { 16,         true,   true,     false,  4 },  // 16 byte header, 4 byte oops, 16-byte align
-    { 256,        false,  false,    false,  32 }, // 20 byte header, 8 byte oops, 256-byte align
-    { 256,        false,  true,     false,  32 }, // 20 byte header, 4 byte oops, 256-byte align
+    { 256,        false,  false,    false,  32 }, // 24 byte header, 8 byte oops, 256-byte align
+    { 256,        false,  true,     false,  32 }, // 24 byte header, 4 byte oops, 256-byte align
     { 256,        true,   false,    false,  32 }, // 16 byte header, 8 byte oops, 256-byte align
     { 256,        true,   true,     false,  32 }, // 16 byte header, 4 byte oops, 256-byte align
     { 8,          false,  false,    true,   3 },  // 16 byte header, 8 byte oops

diff --git a/test/hotspot/jtreg/runtime/FieldLayout/BaseOffsets.java b/test/hotspot/jtreg/runtime/FieldLayout/BaseOffsets.java
@@ -96,7 +96,7 @@ static class LIClass {
             LONG_ARRAY_OFFSET = 16;
         } else {
             INT_OFFSET = 16;
-            INT_ARRAY_OFFSET = 20;
+            INT_ARRAY_OFFSET = 24;
             LONG_ARRAY_OFFSET = 24;
         }
     }

diff --git a/test/jdk/java/lang/instrument/GetObjectSizeIntrinsicsTest.java b/test/jdk/java/lang/instrument/GetObjectSizeIntrinsicsTest.java
@@ -315,7 +315,7 @@ public class GetObjectSizeIntrinsicsTest extends ASimpleInstrumentationTestCase
     static final int LARGE_OBJ_ARRAY_SIZE = (4096/(int)REF_SIZE)*1024*1024 + 1024;
 
     static final boolean CCP = WhiteBox.getWhiteBox().getBooleanVMFlag("UseCompressedClassPointers");
-    static final int ARRAY_HEADER_SIZE = CCP ? 16 : (Platform.is64bit() ? 20 : 16);
+    static final int ARRAY_HEADER_SIZE = CCP ? 16 : (Platform.is64bit() ? 24 : 16);
 
     final String mode;