Print string contents for "this" references

The changes reflect the feature request #20878. Print string contents for this references. Also, print address for string arguments and returns. Closes: #20878 Signed-off-by: Nick Kamal <[email protected]>
eclipse-openj9 · Feb 4, 2025 · c8eb717 · c8eb717
1 parent 0ab22ee
commit c8eb717
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Showing 2 changed files with 41 additions and 6 deletions.
diff --git a/runtime/rastrace/method_trace.c b/runtime/rastrace/method_trace.c
@@ -172,6 +172,10 @@ traceMethodEnter(J9VMThread *thr, J9Method *method, void *receiverAddress, UDATA
 	J9UTF8* methodName = J9ROMMETHOD_NAME(J9_ROM_METHOD_FROM_RAM_METHOD(method));
 	J9UTF8* methodSignature = J9ROMMETHOD_SIGNATURE(J9_ROM_METHOD_FROM_RAM_METHOD(method));
 	UDATA modifiers = J9_ROM_METHOD_FROM_RAM_METHOD(method)->modifiers;
+	j9object_t receiver = *(j9object_t*)receiverAddress;
+	J9Class* receiverClazz = J9OBJECT_CLAZZ(thr, receiver);
+	J9JavaVM *vm = thr->javaVM;
+	const unsigned int maxStringLength = RAS_GLOBAL_FROM_JAVAVM(maxStringLength, vm);
 
 	if (isCompiled) {
 		if (modifiers & J9AccStatic) {
@@ -193,8 +197,6 @@ traceMethodEnter(J9VMThread *thr, J9Method *method, void *receiverAddress, UDATA
 				Trc_MethodArgumentsS(thr, traceMethodArguments(thr, methodSignature, (UDATA*)receiverAddress, buf, buf + sizeof(buf)));
 			}
 		} else {
-			j9object_t receiver = *(j9object_t*)receiverAddress;
-			J9Class* receiverClazz = J9OBJECT_CLAZZ(thr, receiver);
 			J9UTF8* receiverClassName = J9ROMCLASS_CLASSNAME(receiverClazz->romClass);
 
 			if (modifiers & J9AccNative) {
@@ -205,14 +207,45 @@ traceMethodEnter(J9VMThread *thr, J9Method *method, void *receiverAddress, UDATA
 
 			if (doParameters) {
 				Trc_MethodArguments(
-						thr, 
+						thr,
 						(U_32)J9UTF8_LENGTH(receiverClassName),
 						J9UTF8_DATA(receiverClassName),
 						receiver,
 						traceMethodArguments(thr, methodSignature, (UDATA*)receiverAddress - 1, buf, buf + sizeof(buf)));
 			}
 		}
 	}
+
+	if ((receiverClazz == J9VMJAVALANGSTRING_OR_NULL(vm))
+		&& (0 != maxStringLength)
+		&& !J9UTF8_LITERAL_EQUALS(J9UTF8_DATA(methodName), J9UTF8_LENGTH(methodName), "<init>")
+	) {
+		PORT_ACCESS_FROM_VMC(thr);
+		char utf8Buffer[RAS_MAX_STRING_LENGTH_LIMIT + 1];
+		char outputString[RAS_MAX_STRING_LENGTH_LIMIT + 1];
+		UDATA utf8Length = 0;
+
+		char *utf8String = vm->internalVMFunctions->copyStringToUTF8WithMemAlloc(
+				thr,
+				receiver,
+				0,
+				"",
+				0,
+				utf8Buffer,
+				sizeof(utf8Buffer),
+				&utf8Length);
+		if (NULL == utf8String) {
+			j9str_printf(outputString, RAS_MAX_STRING_LENGTH_LIMIT + 1, "(String)@%p - <Memory allocation error>", receiver);
+		} else if (utf8Length > maxStringLength) {
+			j9str_printf(outputString, RAS_MAX_STRING_LENGTH_LIMIT + 1, "(String)@%p - \"%.*s\"...", receiver, (U_32)maxStringLength, utf8String);
+		} else {
+			j9str_printf(outputString, RAS_MAX_STRING_LENGTH_LIMIT + 1, "(String)@%p - \"%.*s\"", receiver, (U_32)utf8Length, utf8String);
+		}
+		Trc_MethodEntryStr(thr, J9UTF8_LENGTH(className), J9UTF8_DATA(className), J9UTF8_LENGTH(methodName), J9UTF8_DATA(methodName), J9UTF8_LENGTH(methodSignature), J9UTF8_DATA(methodSignature), J9UTF8_LENGTH(outputString), outputString);
+		if (utf8Buffer != utf8String) {
+			j9mem_free_memory(utf8String);
+		}
+	}
 }
 
 /**************************************************************************
@@ -496,11 +529,11 @@ traceMethodArgObject(J9VMThread *thr, UDATA* arg0EA, char* cursor, UDATA length)
 					&utf8Length);
 
 			if (NULL == utf8String) {
-				j9str_printf(cursor, length, "(String)<Memory allocation error>");
+				j9str_printf(cursor, length, "(String)@%p - <Memory allocation error>", object);
 			} else if (utf8Length > maxStringLength) {
-				j9str_printf(cursor, length, "(String)\"%.*s\"...", (U_32)maxStringLength, utf8String);
+				j9str_printf(cursor, length, "(String)@%p - \"%.*s\"...", object, (U_32)maxStringLength, utf8String);
 			} else {
-				j9str_printf(cursor, length, "(String)\"%.*s\"", (U_32)utf8Length, utf8String);
+				j9str_printf(cursor, length, "(String)@%p - \"%.*s\"", object, (U_32)utf8Length, utf8String);
 			}
 
 			if (utf8Buffer != utf8String) {

diff --git a/runtime/rastrace/mt.tdf b/runtime/rastrace/mt.tdf
@@ -59,3 +59,5 @@ TraceExit-Exception=Trc_MethodExitNXS Overhead=1 Level=5 Group=throw,nativeMetho
 
 TraceEvent=Trc_MethodReturn Overhead=1 Level=5 Group=methodArguments Template="return value: %s"
 TraceEvent=Trc_MethodException Overhead=1 Level=5 Group=methodArguments Template="exception: %s"
+
+TraceEntry=Trc_MethodEntryStr Overhead=1 Level=5 Template="%.*s.%.*s%.*s, this = %.*s"
Original file line number	Diff line number	Diff line change
Expand Up		@@ -59,3 +59,5 @@ TraceExit-Exception=Trc_MethodExitNXS Overhead=1 Level=5 Group=throw,nativeMetho

		TraceEvent=Trc_MethodReturn Overhead=1 Level=5 Group=methodArguments Template="return value: %s"
		TraceEvent=Trc_MethodException Overhead=1 Level=5 Group=methodArguments Template="exception: %s"

		TraceEntry=Trc_MethodEntryStr Overhead=1 Level=5 Template="%.s.%.s%.s, this = %.s"