Improved -removeassertions ikvmc optimization to remove more code (esp. allow otherwise empty <clinit> methods to be optimized away).

5 files changed, 184 insertions, 42 deletions

diff --git a/openjdk/response.txt b/openjdk/response.txt
index 37e32097..9bc69a05 100644
--- a/openjdk/response.txt
+++ b/openjdk/response.txt
@@ -193,7 +193,7 @@
 }
 {
     -out:IKVM.OpenJDK.Corba.dll
-    -baseaddress:0x57350000
+    -baseaddress:0x57320000
     -recurse:resources.zip/com/sun/corba/*
     -recurse:resources.zip/com/sun/jndi/cosnaming/jndiprovider.properties
     -resource:com/sun/corba/se/impl/logging/LogStrings.properties=@OPENJDK@/build/linux-x86_64-normal-server-release/jdk/classes/com/sun/corba/se/impl/logging/LogStrings.properties
@@ -314,7 +314,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.API.dll
-    -baseaddress:0x57980000
+    -baseaddress:0x57950000
     -resource:META-INF/services/sun.util.spi.XmlPropertiesProvider=@OPENJDK@/jdk/src/share/classes/sun/util/xml/META-INF/services/sun.util.spi.XmlPropertiesProvider
     @OPENJDK@/jaxp/src/javax/xml/*.class
     @OPENJDK@/jaxp/src/javax/xml/datatype/*.class
@@ -349,7 +349,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.XPath.dll
-    -baseaddress:0x57A40000
+    -baseaddress:0x57A10000
     -recurse:resources.zip/com/sun/org/apache/xalan/internal/res/*
     @OPENJDK@/jaxp/src/com/sun/org/apache/xalan/internal/extensions/*.class
     @OPENJDK@/jaxp/src/com/sun/org/apache/xalan/internal/res/*.class
@@ -374,7 +374,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.Parse.dll
-    -baseaddress:0x57DA0000
+    -baseaddress:0x57D70000
     -recurse:resources.zip/com/sun/org/apache/xerces/*
     -recurse:resources.zip/com/sun/org/apache/xml/internal/*
     -recurse:resources.zip/com/sun/xml/internal/stream/*
@@ -437,7 +437,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.Transform.dll
-    -baseaddress:0x58580000
+    -baseaddress:0x58550000
     @OPENJDK@/jaxp/src/com/sun/java_cup/internal/runtime/*.class
     @OPENJDK@/jaxp/src/com/sun/org/apache/bcel/internal/*.class
     @OPENJDK@/jaxp/src/com/sun/org/apache/bcel/internal/classfile/*.class
@@ -461,7 +461,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.Bind.dll
-    -baseaddress:0x589D0000
+    -baseaddress:0x589A0000
     -recurse:resources.zip/javax/xml/bind/*
     -recurse:resources.zip/com/sun/xml/internal/bind/*
     -recurse:resources.zip/com/sun/xml/internal/fastinfoset/*
@@ -520,7 +520,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.WebServices.dll
-    -baseaddress:0x58DF0000
+    -baseaddress:0x58DC0000
     -recurse:resources.zip/com/sun/xml/internal/messaging/*
     -recurse:resources.zip/com/sun/xml/internal/ws/*
     @OPENJDK@/jaxws/src/share/jaxws_classes/com/oracle/webservices/internal/api/*.class
@@ -661,7 +661,7 @@
 }
 {
     -out:IKVM.OpenJDK.XML.Crypto.dll
-    -baseaddress:0x59600000
+    -baseaddress:0x595D0000
     @OPENJDK@/jdk/src/share/classes/com/sun/org/apache/xml/internal/security/*.class
     @OPENJDK@/jdk/src/share/classes/com/sun/org/apache/xml/internal/security/algorithms/*.class
     @OPENJDK@/jdk/src/share/classes/com/sun/org/apache/xml/internal/security/algorithms/implementations/*.class
@@ -697,7 +697,7 @@
 }
 {
     -out:IKVM.OpenJDK.SwingAWT.dll
-    -baseaddress:0x59780000
+    -baseaddress:0x59750000
     -remap:swingawt.xml
     -resource:META-INF/services/sun.java2d.pipe.RenderingEngine=resources/META-INF/services/sun.java2d.pipe.RenderingEngine
     -resource:META-INF/services/sun.java2d.cmm.CMMServiceProvider=@OPENJDK@/jdk/src/share/classes/sun/java2d/cmm/lcms/META-INF/services/sun.java2d.cmm.CMMServiceProvider
@@ -797,14 +797,14 @@
 }
 {
     -out:IKVM.OpenJDK.Charsets.dll
-    -baseaddress:0x5A9B0000
+    -baseaddress:0x5A980000
     -resource:sun/nio/cs/ext/sjis0213.dat=@OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/nio/cs/ext/sjis0213.dat
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/nio/cs/ext/*.class
     @OPENJDK@/jdk/src/share/classes/sun/nio/cs/ext/*.class
 }
 {
     -out:IKVM.OpenJDK.Util.dll
-    -baseaddress:0x5AEC0000
+    -baseaddress:0x5AE90000
     -recurse:resources.zip/com/sun/java/util/jar/pack/intrinsic.properties
     -recurse:resources.zip/sun/launcher/resources/*
     -resource:META-INF/services/java.nio.file.spi.FileSystemProvider=@OPENJDK@/jdk/src/share/demo/nio/zipfs/src/META-INF/services/java.nio.file.spi.FileSystemProvider
@@ -830,7 +830,7 @@
 }
 {
     -out:IKVM.OpenJDK.Text.dll
-    -baseaddress:0x5B190000
+    -baseaddress:0x5B160000
     -recurse:resources.zip/sun/text/resources/*
     @OPENJDK@/jdk/src/share/classes/java/text/*.class
     @OPENJDK@/jdk/src/share/classes/java/text/spi/*.class
@@ -842,7 +842,7 @@
 }
 {
     -out:IKVM.OpenJDK.Security.dll
-    -baseaddress:0x5B340000
+    -baseaddress:0x5B310000
     -remap:security.xml
     sun/security/jgss/wrapper/*.class
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/security/util/*.class
@@ -916,7 +916,7 @@
 }
 {
     -out:IKVM.OpenJDK.Management.dll
-    -baseaddress:0x5BB80000
+    -baseaddress:0x5BB50000
     java/lang/management/*.class
     sun/management/*.class
     rmistubs/org/omg/stub/javax/management/remote/rmi/*.class
@@ -950,7 +950,7 @@
 }
 {
     -out:IKVM.OpenJDK.Misc.dll
-    -baseaddress:0x5BF10000
+    -baseaddress:0x5BEE0000
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/misc/resources/*.class
     @OPENJDK@/corba/src/share/classes/javax/activity/*.class
     @OPENJDK@/jaxws/src/share/jaxws_classes/javax/annotation/*.class
@@ -981,7 +981,7 @@
 }
 {
     -out:IKVM.OpenJDK.Naming.dll
-    -baseaddress:0x5BFD0000
+    -baseaddress:0x5BFA0000
     -recurse:resources.zip/com/sun/jndi/ldap/jndiprovider.properties
     -resource:META-INF/services/sun.net.spi.nameservice.NameServiceDescriptor=@OPENJDK@/jdk/src/share/classes/sun/net/spi/nameservice/dns/META-INF/services/sun.net.spi.nameservice.NameServiceDescriptor
     sun/net/dns/*.class
@@ -1007,7 +1007,7 @@
 }
 {
     -out:IKVM.OpenJDK.Jdbc.dll
-    -baseaddress:0x5C150000
+    -baseaddress:0x5C120000
     -resource:META-INF/services/java.sql.Driver=resources/META-INF/services/java.sql.Driver
     -recurse:resources.zip/com/sun/rowset/*
     -recurse:resources.zip/javax/sql/*
@@ -1024,7 +1024,7 @@
 }
 {
     -out:IKVM.OpenJDK.Remoting.dll
-    -baseaddress:0x5C2D0000
+    -baseaddress:0x5C2A0000
     -recurse:resources.zip/sun/rmi/*
     rmistubs/com/sun/jndi/rmi/registry/*.class
     rmistubs/java/rmi/activation/*.class
@@ -1050,7 +1050,7 @@
 }
 {
     -out:IKVM.OpenJDK.Beans.dll
-    -baseaddress:0x5C420000
+    -baseaddress:0x5C3F0000
     -resource:META-INF/mailcap.default=@OPENJDK@/jaxws/src/share/jaf_classes/META-INF/mailcap.default
     -resource:META-INF/mimetypes.default=@OPENJDK@/jaxws/src/share/jaf_classes/META-INF/mimetypes.default
     @OPENJDK@/jaxws/src/share/jaf_classes/com/sun/activation/registries/*.class
@@ -1066,7 +1066,7 @@
 }
 {
     -out:IKVM.OpenJDK.Media.dll
-    -baseaddress:0x5C510000
+    -baseaddress:0x5C4E0000
     -resource:META-INF/services/javax.print.PrintServiceLookup=@OPENJDK@/jdk/src/windows/classes/sun/print/services/javax.print.PrintServiceLookup
     -resource:META-INF/services/javax.print.StreamPrintServiceFactory=@OPENJDK@/jdk/src/windows/classes/sun/print/services/javax.print.StreamPrintServiceFactory
     -resource:META-INF/services/javax.sound.midi.spi.MidiDeviceProvider=@OPENJDK@/jdk/src/share/classes/com/sun/media/sound/services/javax.sound.midi.spi.MidiDeviceProvider
@@ -1113,7 +1113,7 @@
 }
 {
     -out:IKVM.OpenJDK.Nashorn.dll
-    -baseaddress:0x5C780000
+    -baseaddress:0x5C750000
     -resource:META-INF/services/javax.script.ScriptEngineFactory=@OPENJDK@/nashorn/src/META-INF/services/javax.script.ScriptEngineFactory
     -resource:jdk/nashorn/internal/runtime/resources/version.properties=resources/nashorn/version.properties
     -recurse:@OPENJDK@/nashorn/src/*.js
@@ -1151,7 +1151,7 @@
 }
 {
     -out:IKVM.OpenJDK.Localedata.dll
-    -baseaddress:0x5CCF0000
+    -baseaddress:0x5CCC0000
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/util/resources/*.class
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/util/resources/ar/*.class
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/util/resources/be/*.class
@@ -1252,7 +1252,7 @@
 }
 {
     -out:IKVM.OpenJDK.Cldrdata.dll
-    -baseaddress:0x5D1D0000
+    -baseaddress:0x5D1A0000
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/text/resources/cldr/*.class
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/text/resources/cldr/aa/*.class
     @OPENJDK@/build/linux-x86_64-normal-server-release/jdk/gensrc/sun/text/resources/cldr/af/*.class
diff --git a/runtime/ClassFile.cs b/runtime/ClassFile.cs
index 89e66874..9752fe83 100644
--- a/runtime/ClassFile.cs
+++ b/runtime/ClassFile.cs
@@ -51,6 +51,7 @@ namespace IKVM.Internal
 		LineNumberTable = 2,
 		RelaxedClassNameValidation = 4,
 		TrustedAnnotations = 8,
+		RemoveAssertions = 16,
 	}
 
 	sealed class ClassFile
@@ -68,6 +69,7 @@ namespace IKVM.Internal
 		private const ushort FLAG_LAMBDAFORM_COMPILED = 0x800;
 		private const ushort FLAG_LAMBDAFORM_HIDDEN = 0x1000;
 		private const ushort FLAG_FORCEINLINE = 0x2000;
+		private const ushort FLAG_HAS_ASSERTIONS = 0x4000;
 		private ConstantPoolItemClass[] interfaces;
 		private Field[] fields;
 		private Method[] methods;
@@ -346,6 +348,10 @@ namespace IKVM.Internal
 						{
 							throw new ClassFormatError("{0} (Method \"{1}\" has illegal signature \"{2}\")", Name, name, sig);
 						}
+						if((options & ClassFileParseOptions.RemoveAssertions) != 0 && methods[i].IsClassInitializer)
+						{
+							RemoveAssertionInit(methods[i]);
+						}
 					}
 				}
 				CheckDuplicates<FieldOrMethod>(methods, "Repetitive method name/signature");
@@ -1311,6 +1317,14 @@ namespace IKVM.Internal
 			flags |= FLAG_MASK_INTERNAL;
 		}
 
+		internal bool HasAssertions
+		{
+			get
+			{
+				return (flags & FLAG_HAS_ASSERTIONS) != 0;
+			}
+		}
+
 		internal bool HasInitializedFields
 		{
 			get
@@ -2706,6 +2720,11 @@ namespace IKVM.Internal
 				}
 			}
 
+			internal void PatchConstantValue(object value)
+			{
+				constantValue = value;
+			}
+
 			internal bool IsStaticFinalConstant
 			{
 				get { return (access_flags & (Modifiers.Final | Modifiers.Static)) == (Modifiers.Final | Modifiers.Static) && constantValue != null; }
@@ -3864,5 +3883,123 @@ namespace IKVM.Internal
 			}
 			return null;
 		}
+
+		private void RemoveAssertionInit(Method m)
+		{
+			/* We match the following code sequence:
+			 *   0  ldc <class X>
+			 *   2  invokevirtual <Method java/lang/Class desiredAssertionStatus()Z>
+			 *   5  ifne 12
+			 *   8  iconst_1
+			 *   9  goto 13
+			 *  12  iconst_0
+			 *  13  putstatic <Field <this class> boolean <static final field>>
+			 */
+			ConstantPoolItemFieldref fieldref;
+			Field field;
+			if (m.Instructions[0].NormalizedOpCode == NormalizedByteCode.__ldc && SafeIsConstantPoolClass(m.Instructions[0].Arg1)
+				&& m.Instructions[1].NormalizedOpCode == NormalizedByteCode.__invokevirtual && IsDesiredAssertionStatusMethodref(m.Instructions[1].Arg1)
+				&& m.Instructions[2].NormalizedOpCode == NormalizedByteCode.__ifne && m.Instructions[2].TargetIndex == 5
+				&& m.Instructions[3].NormalizedOpCode == NormalizedByteCode.__iconst && m.Instructions[3].Arg1 == 1
+				&& m.Instructions[4].NormalizedOpCode == NormalizedByteCode.__goto && m.Instructions[4].TargetIndex == 6
+				&& m.Instructions[5].NormalizedOpCode == NormalizedByteCode.__iconst && m.Instructions[5].Arg1 == 0
+				&& m.Instructions[6].NormalizedOpCode == NormalizedByteCode.__putstatic && (fieldref = SafeGetFieldref(m.Instructions[6].Arg1)) != null
+				&& fieldref.Class == Name && fieldref.Signature == "Z"
+				&& (field = GetField(fieldref.Name, fieldref.Signature)) != null
+				&& field.IsStatic && field.IsFinal
+				&& !HasBranchIntoRegion(m.Instructions, 7, m.Instructions.Length, 0, 7)
+				&& !HasStaticFieldWrite(m.Instructions, 7, m.Instructions.Length, field)
+				&& !HasExceptionHandlerInRegion(m.ExceptionTable, 0, 7))
+			{
+				field.PatchConstantValue(true);
+				m.Instructions[0].PatchOpCode(NormalizedByteCode.__goto, 7);
+				flags |= FLAG_HAS_ASSERTIONS;
+			}
+		}
+
+		private bool IsDesiredAssertionStatusMethodref(int cpi)
+		{
+			ConstantPoolItemMethodref method = SafeGetMethodref(cpi) as ConstantPoolItemMethodref;
+			return method != null
+				&& method.Class == "java.lang.Class"
+				&& method.Name == "desiredAssertionStatus"
+				&& method.Signature == "()Z";
+		}
+
+		private static bool HasBranchIntoRegion(Method.Instruction[] instructions, int checkStart, int checkEnd, int regionStart, int regionEnd)
+		{
+			for (int i = checkStart; i < checkEnd; i++)
+			{
+				switch (instructions[i].NormalizedOpCode)
+				{
+					case NormalizedByteCode.__ifeq:
+					case NormalizedByteCode.__ifne:
+					case NormalizedByteCode.__iflt:
+					case NormalizedByteCode.__ifge:
+					case NormalizedByteCode.__ifgt:
+					case NormalizedByteCode.__ifle:
+					case NormalizedByteCode.__if_icmpeq:
+					case NormalizedByteCode.__if_icmpne:
+					case NormalizedByteCode.__if_icmplt:
+					case NormalizedByteCode.__if_icmpge:
+					case NormalizedByteCode.__if_icmpgt:
+					case NormalizedByteCode.__if_icmple:
+					case NormalizedByteCode.__if_acmpeq:
+					case NormalizedByteCode.__if_acmpne:
+					case NormalizedByteCode.__ifnull:
+					case NormalizedByteCode.__ifnonnull:
+					case NormalizedByteCode.__goto:
+					case NormalizedByteCode.__jsr:
+						if (instructions[i].TargetIndex > regionStart && instructions[i].TargetIndex < regionEnd)
+						{
+							return true;
+						}
+						break;
+					case NormalizedByteCode.__tableswitch:
+					case NormalizedByteCode.__lookupswitch:
+						if (instructions[i].DefaultTarget > regionStart && instructions[i].DefaultTarget < regionEnd)
+						{
+							return true;
+						}
+						for (int j = 0; j < instructions[i].SwitchEntryCount; j++)
+						{
+							if (instructions[i].GetSwitchTargetIndex(j) > regionStart && instructions[i].GetSwitchTargetIndex(j) < regionEnd)
+							{
+								return true;
+							}
+						}
+						break;
+				}
+			}
+			return false;
+		}
+
+		private bool HasStaticFieldWrite(Method.Instruction[] instructions, int checkStart, int checkEnd, Field field)
+		{
+			for (int i = checkStart; i < checkEnd; i++)
+			{
+				if (instructions[i].NormalizedOpCode == NormalizedByteCode.__putstatic)
+				{
+					ConstantPoolItemFieldref fieldref = SafeGetFieldref(instructions[i].Arg1);
+					if (fieldref != null && fieldref.Class == Name && fieldref.Name == field.Name && fieldref.Signature == field.Signature)
+					{
+						return true;
+					}
+				}
+			}
+			return false;
+		}
+
+		private static bool HasExceptionHandlerInRegion(Method.ExceptionTableEntry[] entries, int regionStart, int regionEnd)
+		{
+			for (int i = 0; i < entries.Length; i++)
+			{
+				if (entries[i].handlerIndex > regionStart && entries[i].handlerIndex < regionEnd)
+				{
+					return true;
+				}
+			}
+			return false;
+		}
 	}
 }
diff --git a/runtime/ClassLoaderWrapper.cs b/runtime/ClassLoaderWrapper.cs
index 48a60068..d04d05dd 100644
--- a/runtime/ClassLoaderWrapper.cs
+++ b/runtime/ClassLoaderWrapper.cs
@@ -1495,6 +1495,10 @@ namespace IKVM.Internal
 				{
 					cfp |= ClassFileParseOptions.TrustedAnnotations;
 				}
+				if (RemoveAsserts)
+				{
+					cfp |= ClassFileParseOptions.RemoveAssertions;
+				}
 				return cfp;
 #else
 				ClassFileParseOptions cfp = ClassFileParseOptions.LineNumberTable;
diff --git a/runtime/DynamicTypeWrapper.cs b/runtime/DynamicTypeWrapper.cs
index 6b1f19c0..72685c14 100644
--- a/runtime/DynamicTypeWrapper.cs
+++ b/runtime/DynamicTypeWrapper.cs
@@ -1147,7 +1147,20 @@ namespace IKVM.Internal
 				noop = true;
 				for (int i = 0; i < m.Instructions.Length; i++)
 				{
-					NormalizedByteCode bc = m.Instructions[i].NormalizedOpCode;
+					NormalizedByteCode bc;
+					while ((bc = m.Instructions[i].NormalizedOpCode) == NormalizedByteCode.__goto)
+					{
+						int target = m.Instructions[i].TargetIndex;
+						if (target <= i)
+						{
+							// backward branch means we can't do anything
+							noop = false;
+							return false;
+						}
+						// we must skip the unused instructions because the "remove assertions" optimization
+						// uses a goto to remove the (now unused) code
+						i = target;
+					}
 					if (bc == NormalizedByteCode.__getstatic || bc == NormalizedByteCode.__putstatic)
 					{
 						ClassFile.ConstantPoolItemFieldref fld = classFile.SafeGetFieldref(m.Instructions[i].Arg1);
diff --git a/runtime/verifier.cs b/runtime/verifier.cs
index b9c5991a..fdeb809d 100644
--- a/runtime/verifier.cs
+++ b/runtime/verifier.cs
@@ -2572,19 +2572,9 @@ sealed class MethodAnalyzer
 		// Optimization pass
 		if (classLoader.RemoveAsserts)
 		{
-			FieldWrapper assertionsDisabled = null;
-			foreach (FieldWrapper fw in wrapper.GetFields())
-			{
-				// HACK we assume that all compilers use the same name for this field (ecj and javac do)
-				if (fw.Name == "$assertionsDisabled" && fw.Signature == "Z"
-					&& (fw.Modifiers & (IKVM.Attributes.Modifiers.AccessMask | IKVM.Attributes.Modifiers.Final | IKVM.Attributes.Modifiers.Static | IKVM.Attributes.Modifiers.Synthetic))
-						== (IKVM.Attributes.Modifiers.Static | IKVM.Attributes.Modifiers.Final | IKVM.Attributes.Modifiers.Synthetic))
-				{
-					assertionsDisabled = fw;
-					break;
-				}
-			}
-			if (assertionsDisabled != null)
+			// While the optimization is general, in practice it never happens that a getstatic is used on a final field,
+			// so we only look for this if assert initialization has been optimized out.
+			if (classFile.HasAssertions)
 			{
 				// compute branch targets
 				InstructionFlags[] flags = MethodAnalyzer.ComputePartialReachability(codeInfo, method.Instructions, exceptions, 0, false);
@@ -2596,12 +2586,10 @@ sealed class MethodAnalyzer
 						&& instructions[i + 1].TargetIndex > i
 						&& (flags[i + 1] & InstructionFlags.BranchTarget) == 0)
 					{
-						ClassFile.ConstantPoolItemFieldref cpi = classFile.GetFieldref(instructions[i].Arg1);
-						if (cpi.GetField() == assertionsDisabled)
+						ConstantFieldWrapper field = classFile.GetFieldref(instructions[i].Arg1).GetField() as ConstantFieldWrapper;
+						if (field != null && field.FieldTypeWrapper == PrimitiveTypeWrapper.BOOLEAN && (bool)field.GetConstantValue())
 						{
-							// We've found an assertion. We patch the instruction to branch around it so that
-							// the assertion code will be unreachable (and hence optimized away).
-							// Note that the goto will be optimized away later by the code generator (which removes unnecessary branches).
+							// We know the branch will always be taken, so we replace the getstatic/ifne by a goto.
 							instructions[i].PatchOpCode(NormalizedByteCode.__goto, instructions[i + 1].TargetIndex);
 						}
 					}