1 /*
2  * Copyright (C) 2017 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <android-base/logging.h>
18 
19 #include "base/casts.h"
20 #include "jni.h"
21 
22 namespace art {
23 
24 // Make the array volatile, which is apparently making the C compiler
25 // use FP registers in the method below.
26 volatile double array[] = { 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10.0, 11.0, 12.0 };
27 
Java_Main_holdFpTemporaries(JNIEnv * env,jclass cls)28 extern "C" JNIEXPORT void JNICALL Java_Main_holdFpTemporaries(JNIEnv* env, jclass cls) {
29   jmethodID mid = env->GetStaticMethodID(cls, "caller", "(IIJ)V");
30   CHECK(mid != nullptr);
31   // Load values from the arrays, which will be loaded in callee-save FP registers.
32   double a = array[0];
33   double b = array[1];
34   double c = array[2];
35   double d = array[3];
36   double e = array[4];
37   double f = array[5];
38   double g = array[6];
39   double h = array[7];
40   double i = array[8];
41   double j = array[9];
42   double k = array[10];
43   double l = array[11];
44   env->CallStaticVoidMethod(cls, mid, 1, 1, 1L);
45   // Load it in a temporary to please C compiler with bit_cast.
46   double temp = array[0];
47   CHECK_EQ(bit_cast<int64_t>(a), bit_cast<int64_t>(temp));
48   temp = array[1];
49   CHECK_EQ(bit_cast<int64_t>(b), bit_cast<int64_t>(temp));
50   temp = array[2];
51   CHECK_EQ(bit_cast<int64_t>(c), bit_cast<int64_t>(temp));
52   temp = array[3];
53   CHECK_EQ(bit_cast<int64_t>(d), bit_cast<int64_t>(temp));
54   temp = array[4];
55   CHECK_EQ(bit_cast<int64_t>(e), bit_cast<int64_t>(temp));
56   temp = array[5];
57   CHECK_EQ(bit_cast<int64_t>(f), bit_cast<int64_t>(temp));
58   temp = array[6];
59   CHECK_EQ(bit_cast<int64_t>(g), bit_cast<int64_t>(temp));
60   temp = array[7];
61   CHECK_EQ(bit_cast<int64_t>(h), bit_cast<int64_t>(temp));
62   temp = array[8];
63   CHECK_EQ(bit_cast<int64_t>(i), bit_cast<int64_t>(temp));
64   temp = array[9];
65   CHECK_EQ(bit_cast<int64_t>(j), bit_cast<int64_t>(temp));
66   temp = array[10];
67   CHECK_EQ(bit_cast<int64_t>(k), bit_cast<int64_t>(temp));
68   temp = array[11];
69   CHECK_EQ(bit_cast<int64_t>(l), bit_cast<int64_t>(temp));
70 }
71 
72 }  // namespace art
73