/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Inlined native functions. These definitions replace interpreted or
* native implementations at runtime; "intrinsic" might be a better word.
*/
#include "Dalvik.h"
#include <math.h>
#ifdef HAVE__MEMCMP16
/* hand-coded assembly implementation, available on some platforms */
//#warning "trying memcmp16"
//#define CHECK_MEMCMP16
/* "count" is in 16-bit units */
extern u4 __memcmp16(const u2* s0, const u2* s1, size_t count);
#endif
/*
* Some notes on "inline" functions.
*
* These are NOT simply native implementations. A full method definition
* must still be provided. Depending on the flags passed into the VM
* at runtime, the original or inline version may be selected by the
* DEX optimizer.
*
* PLEASE DO NOT use this as the default location for native methods.
* The difference between this and an "internal native" static method
* call on a 200MHz ARM 9 is roughly 370ns vs. 700ns. The code here
* "secretly replaces" the other method, so you can't avoid having two
* implementations. Since the DEX optimizer mode can't be known ahead
* of time, both implementations must be correct and complete.
*
* The only stuff that really needs to be here are methods that
* are high-volume or must be low-overhead, e.g. certain String/Math
* methods and some java.util.concurrent.atomic operations.
*
* Normally, a class is loaded and initialized the first time a static
* method is invoked. This property is NOT preserved here. If you need
* to access a static field in a class, you must ensure initialization
* yourself (cheap/easy way is to check the resolved-methods table, and
* resolve the method if it hasn't been).
*
* DO NOT replace "synchronized" methods. We do not support method
* synchronization here.
*
* Remember that these functions are executing while the thread is in
* the "RUNNING" state, not the "NATIVE" state. If you perform a blocking
* operation you can stall the entire VM if the GC or debugger wants to
* suspend the thread. Since these are arguably native implementations
* rather than VM internals, prefer NATIVE to VMWAIT if you want to change
* the thread state.
*
* Always write results to 32-bit or 64-bit fields in "pResult", e.g. do
* not write boolean results to pResult->z. The interpreter expects
* 32 or 64 bits to be set.
*
* Inline op methods return "false" if an exception was thrown, "true" if
* everything went well.
*
* DO NOT provide implementations of methods that can be overridden by a
* subclass, as polymorphism does not work correctly. For safety you should
* only provide inline functions for classes/methods declared "final".
*
* It's best to avoid inlining the overridden version of a method. For
* example, String.hashCode() is inherited from Object.hashCode(). Code
* calling String.hashCode() through an Object reference will run the
* "slow" version, while calling it through a String reference gets
* the inlined version. It's best to have just one version unless there
* are clear performance gains.
*
* Because the actual method is not called, debugger breakpoints on these
* methods will not happen. (TODO: have the code here find the original
* method and call it when the debugger is active.) Additional steps have
* been taken to allow method profiling to produce correct results.
*/
/*
* ===========================================================================
* org.apache.harmony.dalvik.NativeTestTarget
* ===========================================================================
*/
/*
* public static void emptyInlineMethod
*
* This exists only for benchmarks.
*/
static bool org_apache_harmony_dalvik_NativeTestTarget_emptyInlineMethod(
u4 arg0, u4 arg1, u4 arg2, u4 arg3, JValue* pResult)
{
// do nothing
return true;
}
/*
* ===========================================================================
* java.lang.String
* ===========================================================================
*/
/*
* public char charAt(int index)
*/
static bool javaLangString_charAt(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
int count, offset;
ArrayObject* chars;
/* null reference check on "this" */
if (!dvmValidateObject((Object*) arg0))
return false;
//LOGI("String.charAt this=0x%08x index=%d\n", arg0, arg1);
count = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_COUNT);
if ((s4) arg1 < 0 || (s4) arg1 >= count) {
dvmThrowException("Ljava/lang/StringIndexOutOfBoundsException;", NULL);
return false;
} else {
offset = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_OFFSET);
chars = (ArrayObject*)
dvmGetFieldObject((Object*) arg0, STRING_FIELDOFF_VALUE);
pResult->i = ((const u2*) chars->contents)[arg1 + offset];
return true;
}
}
#ifdef CHECK_MEMCMP16
/*
* Utility function when we're evaluating alternative implementations.
*/
static void badMatch(StringObject* thisStrObj, StringObject* compStrObj,
int expectResult, int newResult, const char* compareType)
{
ArrayObject* thisArray;
ArrayObject* compArray;
const char* thisStr;
const char* compStr;
int thisOffset, compOffset, thisCount, compCount;
thisCount =
dvmGetFieldInt((Object*) thisStrObj, STRING_FIELDOFF_COUNT);
compCount =
dvmGetFieldInt((Object*) compStrObj, STRING_FIELDOFF_COUNT);
thisOffset =
dvmGetFieldInt((Object*) thisStrObj, STRING_FIELDOFF_OFFSET);
compOffset =
dvmGetFieldInt((Object*) compStrObj, STRING_FIELDOFF_OFFSET);
thisArray = (ArrayObject*)
dvmGetFieldObject((Object*) thisStrObj, STRING_FIELDOFF_VALUE);
compArray = (ArrayObject*)
dvmGetFieldObject((Object*) compStrObj, STRING_FIELDOFF_VALUE);
thisStr = dvmCreateCstrFromString(thisStrObj);
compStr = dvmCreateCstrFromString(compStrObj);
LOGE("%s expected %d got %d\n", compareType, expectResult, newResult);
LOGE(" this (o=%d l=%d) '%s'\n", thisOffset, thisCount, thisStr);
LOGE(" comp (o=%d l=%d) '%s'\n", compOffset, compCount, compStr);
dvmPrintHexDumpEx(ANDROID_LOG_INFO, LOG_TAG,
((const u2*) thisArray->contents) + thisOffset, thisCount*2,
kHexDumpLocal);
dvmPrintHexDumpEx(ANDROID_LOG_INFO, LOG_TAG,
((const u2*) compArray->contents) + compOffset, compCount*2,
kHexDumpLocal);
dvmAbort();
}
#endif
/*
* public int compareTo(String s)
*/
static bool javaLangString_compareTo(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
/*
* Null reference check on "this". Normally this is performed during
* the setup of the virtual method call. We need to do it before
* anything else. While we're at it, check out the other string,
* which must also be non-null.
*/
if (!dvmValidateObject((Object*) arg0) ||
!dvmValidateObject((Object*) arg1))
{
return false;
}
/* quick test for comparison with itself */
if (arg0 == arg1) {
pResult->i = 0;
return true;
}
/*
* This would be simpler and faster if we promoted StringObject to
* a full representation, lining up the C structure fields with the
* actual object fields.
*/
int thisCount, thisOffset, compCount, compOffset;
ArrayObject* thisArray;
ArrayObject* compArray;
const u2* thisChars;
const u2* compChars;
int i, minCount, countDiff;
thisCount = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_COUNT);
compCount = dvmGetFieldInt((Object*) arg1, STRING_FIELDOFF_COUNT);
countDiff = thisCount - compCount;
minCount = (countDiff < 0) ? thisCount : compCount;
thisOffset = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_OFFSET);
compOffset = dvmGetFieldInt((Object*) arg1, STRING_FIELDOFF_OFFSET);
thisArray = (ArrayObject*)
dvmGetFieldObject((Object*) arg0, STRING_FIELDOFF_VALUE);
compArray = (ArrayObject*)
dvmGetFieldObject((Object*) arg1, STRING_FIELDOFF_VALUE);
thisChars = ((const u2*) thisArray->contents) + thisOffset;
compChars = ((const u2*) compArray->contents) + compOffset;
#ifdef HAVE__MEMCMP16
/*
* Use assembly version, which returns the difference between the
* characters. The annoying part here is that 0x00e9 - 0xffff != 0x00ea,
* because the interpreter converts the characters to 32-bit integers
* *without* sign extension before it subtracts them (which makes some
* sense since "char" is unsigned). So what we get is the result of
* 0x000000e9 - 0x0000ffff, which is 0xffff00ea.
*/
int otherRes = __memcmp16(thisChars, compChars, minCount);
# ifdef CHECK_MEMCMP16
for (i = 0; i < minCount; i++) {
if (thisChars[i] != compChars[i]) {
pResult->i = (s4) thisChars[i] - (s4) compChars[i];
if (pResult->i != otherRes) {
badMatch((StringObject*) arg0, (StringObject*) arg1,
pResult->i, otherRes, "compareTo");
}
return true;
}
}
# endif
if (otherRes != 0) {
pResult->i = otherRes;
return true;
}
#else
/*
* Straightforward implementation, examining 16 bits at a time. Compare
* the characters that overlap, and if they're all the same then return
* the difference in lengths.
*/
for (i = 0; i < minCount; i++) {
if (thisChars[i] != compChars[i]) {
pResult->i = (s4) thisChars[i] - (s4) compChars[i];
return true;
}
}
#endif
pResult->i = countDiff;
return true;
}
/*
* public boolean equals(Object anObject)
*/
static bool javaLangString_equals(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
/*
* Null reference check on "this".
*/
if (!dvmValidateObject((Object*) arg0))
return false;
/* quick test for comparison with itself */
if (arg0 == arg1) {
pResult->i = true;
return true;
}
/*
* See if the other object is also a String.
*
* str.equals(null) is expected to return false, presumably based on
* the results of the instanceof test.
*/
if (arg1 == 0 || ((Object*) arg0)->clazz != ((Object*) arg1)->clazz) {
pResult->i = false;
return true;
}
/*
* This would be simpler and faster if we promoted StringObject to
* a full representation, lining up the C structure fields with the
* actual object fields.
*/
int thisCount, thisOffset, compCount, compOffset;
ArrayObject* thisArray;
ArrayObject* compArray;
const u2* thisChars;
const u2* compChars;
int i;
/* quick length check */
thisCount = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_COUNT);
compCount = dvmGetFieldInt((Object*) arg1, STRING_FIELDOFF_COUNT);
if (thisCount != compCount) {
pResult->i = false;
return true;
}
thisOffset = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_OFFSET);
compOffset = dvmGetFieldInt((Object*) arg1, STRING_FIELDOFF_OFFSET);
thisArray = (ArrayObject*)
dvmGetFieldObject((Object*) arg0, STRING_FIELDOFF_VALUE);
compArray = (ArrayObject*)
dvmGetFieldObject((Object*) arg1, STRING_FIELDOFF_VALUE);
thisChars = ((const u2*) thisArray->contents) + thisOffset;
compChars = ((const u2*) compArray->contents) + compOffset;
#ifdef HAVE__MEMCMP16
pResult->i = (__memcmp16(thisChars, compChars, thisCount) == 0);
# ifdef CHECK_MEMCMP16
int otherRes = (memcmp(thisChars, compChars, thisCount * 2) == 0);
if (pResult->i != otherRes) {
badMatch((StringObject*) arg0, (StringObject*) arg1,
otherRes, pResult->i, "equals-1");
}
# endif
#else
/*
* Straightforward implementation, examining 16 bits at a time. The
* direction of the loop doesn't matter, and starting at the end may
* give us an advantage when comparing certain types of strings (e.g.
* class names).
*
* We want to go forward for benchmarks against __memcmp16 so we get a
* meaningful comparison when the strings don't match (could also test
* with palindromes).
*/
//for (i = 0; i < thisCount; i++)
for (i = thisCount-1; i >= 0; --i)
{
if (thisChars[i] != compChars[i]) {
pResult->i = false;
return true;
}
}
pResult->i = true;
#endif
return true;
}
/*
* public int length()
*/
static bool javaLangString_length(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
//LOGI("String.length this=0x%08x pResult=%p\n", arg0, pResult);
/* null reference check on "this" */
if (!dvmValidateObject((Object*) arg0))
return false;
pResult->i = dvmGetFieldInt((Object*) arg0, STRING_FIELDOFF_COUNT);
return true;
}
/*
* Determine the index of the first character matching "ch". The string
* to search is described by "chars", "offset", and "count".
*
* The "ch" parameter is allowed to be > 0xffff. Our Java-language
* implementation does not currently handle this, so neither do we.
*
* The "start" parameter must be clamped to [0..count].
*
* Returns -1 if no match is found.
*/
static inline int indexOfCommon(Object* strObj, int ch, int start)
{
//if ((ch & 0xffff) != ch) /* 32-bit code point */
// return -1;
/* pull out the basic elements */
ArrayObject* charArray =
(ArrayObject*) dvmGetFieldObject(strObj, STRING_FIELDOFF_VALUE);
const u2* chars = (const u2*) charArray->contents;
int offset = dvmGetFieldInt(strObj, STRING_FIELDOFF_OFFSET);
int count = dvmGetFieldInt(strObj, STRING_FIELDOFF_COUNT);
//LOGI("String.indexOf(0x%08x, 0x%04x, %d) off=%d count=%d\n",
// (u4) strObj, ch, start, offset, count);
/* factor out the offset */
chars += offset;
if (start < 0)
start = 0;
#if 0
/* 16-bit loop, simple */
while (start < count) {
if (chars[start] == ch)
return start;
start++;
}
#else
/* 16-bit loop, slightly better on ARM */
const u2* ptr = chars + start;
const u2* endPtr = chars + count;
while (ptr < endPtr) {
if (*ptr++ == ch)
return (ptr-1) - chars;
}
#endif
return -1;
}
/*
* public int indexOf(int c)
*
* Scan forward through the string for a matching character.
*/
static bool javaLangString_indexOf_I(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
/* null reference check on "this" */
if (!dvmValidateObject((Object*) arg0))
return false;
pResult->i = indexOfCommon((Object*) arg0, arg1, 0);
return true;
}
/*
* public int indexOf(int c, int start)
*
* Scan forward through the string for a matching character.
*/
static bool javaLangString_indexOf_II(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
/* null reference check on "this" */
if (!dvmValidateObject((Object*) arg0))
return false;
pResult->i = indexOfCommon((Object*) arg0, arg1, arg2);
return true;
}
/*
* ===========================================================================
* java.lang.Math
* ===========================================================================
*/
/*
* public static int abs(int)
*/
static bool javaLangMath_abs_int(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
s4 val = (s4) arg0;
pResult->i = (val >= 0) ? val : -val;
return true;
}
/*
* public static long abs(long)
*/
static bool javaLangMath_abs_long(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
union {
u4 arg[2];
s8 ll;
} convert;
convert.arg[0] = arg0;
convert.arg[1] = arg1;
s8 val = convert.ll;
pResult->j = (val >= 0) ? val : -val;
return true;
}
/*
* public static float abs(float)
*/
static bool javaLangMath_abs_float(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
union {
u4 arg;
float ff;
} convert;
/* clear the sign bit; assumes a fairly common fp representation */
convert.arg = arg0 & 0x7fffffff;
pResult->f = convert.ff;
return true;
}
/*
* public static double abs(double)
*/
static bool javaLangMath_abs_double(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
union {
u4 arg[2];
s8 ll;
double dd;
} convert;
/* clear the sign bit in the (endian-dependent) high word */
convert.arg[0] = arg0;
convert.arg[1] = arg1;
convert.ll &= 0x7fffffffffffffffULL;
pResult->d = convert.dd;
return true;
}
/*
* public static int min(int)
*/
static bool javaLangMath_min_int(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
pResult->i = ((s4) arg0 < (s4) arg1) ? arg0 : arg1;
return true;
}
/*
* public static int max(int)
*/
static bool javaLangMath_max_int(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
pResult->i = ((s4) arg0 > (s4) arg1) ? arg0 : arg1;
return true;
}
/*
* public static double sqrt(double)
*
* With ARM VFP enabled, gcc turns this into an fsqrtd instruction, followed
* by an fcmpd of the result against itself. If it doesn't match (i.e.
* it's NaN), the libm sqrt() is invoked.
*/
static bool javaLangMath_sqrt(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
union {
u4 arg[2];
double dd;
} convert;
convert.arg[0] = arg0;
convert.arg[1] = arg1;
pResult->d = sqrt(convert.dd);
return true;
}
/*
* public static double cos(double)
*/
static bool javaLangMath_cos(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
union {
u4 arg[2];
double dd;
} convert;
convert.arg[0] = arg0;
convert.arg[1] = arg1;
pResult->d = cos(convert.dd);
return true;
}
/*
* public static double sin(double)
*/
static bool javaLangMath_sin(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult)
{
union {
u4 arg[2];
double dd;
} convert;
convert.arg[0] = arg0;
convert.arg[1] = arg1;
pResult->d = sin(convert.dd);
return true;
}
/*
* ===========================================================================
* Infrastructure
* ===========================================================================
*/
/*
* Table of methods.
*
* The DEX optimizer uses the class/method/signature string fields to decide
* which calls it can trample. The interpreter just uses the function
* pointer field.
*
* IMPORTANT: you must update DALVIK_VM_BUILD in DalvikVersion.h if you make
* changes to this table.
*
* NOTE: If present, the JIT will also need to know about changes
* to this table. Update the NativeInlineOps enum in InlineNative.h and
* the dispatch code in compiler/codegen/<target>/Codegen.c.
*/
const InlineOperation gDvmInlineOpsTable[] = {
{ org_apache_harmony_dalvik_NativeTestTarget_emptyInlineMethod,
"Lorg/apache/harmony/dalvik/NativeTestTarget;",
"emptyInlineMethod", "()V" },
{ javaLangString_charAt,
"Ljava/lang/String;", "charAt", "(I)C" },
{ javaLangString_compareTo,
"Ljava/lang/String;", "compareTo", "(Ljava/lang/String;)I" },
{ javaLangString_equals,
"Ljava/lang/String;", "equals", "(Ljava/lang/Object;)Z" },
{ javaLangString_indexOf_I,
"Ljava/lang/String;", "indexOf", "(I)I" },
{ javaLangString_indexOf_II,
"Ljava/lang/String;", "indexOf", "(II)I" },
{ javaLangString_length,
"Ljava/lang/String;", "length", "()I" },
{ javaLangMath_abs_int,
"Ljava/lang/Math;", "abs", "(I)I" },
{ javaLangMath_abs_long,
"Ljava/lang/Math;", "abs", "(J)J" },
{ javaLangMath_abs_float,
"Ljava/lang/Math;", "abs", "(F)F" },
{ javaLangMath_abs_double,
"Ljava/lang/Math;", "abs", "(D)D" },
{ javaLangMath_min_int,
"Ljava/lang/Math;", "min", "(II)I" },
{ javaLangMath_max_int,
"Ljava/lang/Math;", "max", "(II)I" },
{ javaLangMath_sqrt,
"Ljava/lang/Math;", "sqrt", "(D)D" },
{ javaLangMath_cos,
"Ljava/lang/Math;", "cos", "(D)D" },
{ javaLangMath_sin,
"Ljava/lang/Math;", "sin", "(D)D" },
};
/*
* Allocate some tables.
*/
bool dvmInlineNativeStartup(void)
{
#ifdef WITH_PROFILER
gDvm.inlinedMethods =
(Method**) calloc(NELEM(gDvmInlineOpsTable), sizeof(Method*));
if (gDvm.inlinedMethods == NULL)
return false;
#endif
return true;
}
/*
* Free generated tables.
*/
void dvmInlineNativeShutdown(void)
{
#ifdef WITH_PROFILER
free(gDvm.inlinedMethods);
#endif
}
/*
* Get a pointer to the inlineops table.
*/
const InlineOperation* dvmGetInlineOpsTable(void)
{
return gDvmInlineOpsTable;
}
/*
* Get the number of entries in the inlineops table.
*/
int dvmGetInlineOpsTableLength(void)
{
return NELEM(gDvmInlineOpsTable);
}
/*
* Make an inline call for the "debug" interpreter, used when the debugger
* or profiler is active.
*/
bool dvmPerformInlineOp4Dbg(u4 arg0, u4 arg1, u4 arg2, u4 arg3,
JValue* pResult, int opIndex)
{
Thread* self = dvmThreadSelf();
bool result;
assert(opIndex >= 0 && opIndex < NELEM(gDvmInlineOpsTable));
#ifdef WITH_PROFILER
/*
* Populate the methods table on first use. It's possible the class
* hasn't been resolved yet, so we need to do the full "calling the
* method for the first time" routine. (It's probably okay to skip
* the access checks.)
*
* Currently assuming that we're only inlining stuff loaded by the
* bootstrap class loader. This is a safe assumption for many reasons.
*/
Method* method = gDvm.inlinedMethods[opIndex];
if (method == NULL) {
ClassObject* clazz;
clazz = dvmFindClassNoInit(
gDvmInlineOpsTable[opIndex].classDescriptor, NULL);
if (clazz == NULL) {
LOGW("Warning: can't find class '%s'\n", clazz->descriptor);
goto skip_prof;
}
method = dvmFindDirectMethodByDescriptor(clazz,
gDvmInlineOpsTable[opIndex].methodName,
gDvmInlineOpsTable[opIndex].methodSignature);
if (method == NULL)
method = dvmFindVirtualMethodByDescriptor(clazz,
gDvmInlineOpsTable[opIndex].methodName,
gDvmInlineOpsTable[opIndex].methodSignature);
if (method == NULL) {
LOGW("Warning: can't find method %s.%s %s\n",
clazz->descriptor,
gDvmInlineOpsTable[opIndex].methodName,
gDvmInlineOpsTable[opIndex].methodSignature);
goto skip_prof;
}
gDvm.inlinedMethods[opIndex] = method;
IF_LOGV() {
char* desc = dexProtoCopyMethodDescriptor(&method->prototype);
LOGV("Registered for profile: %s.%s %s\n",
method->clazz->descriptor, method->name, desc);
free(desc);
}
}
TRACE_METHOD_ENTER(self, method);
result = (*gDvmInlineOpsTable[opIndex].func)(arg0, arg1, arg2, arg3,
pResult);
TRACE_METHOD_EXIT(self, method);
return result;
skip_prof:
#endif
return (*gDvmInlineOpsTable[opIndex].func)(arg0, arg1, arg2, arg3, pResult);
}