vixl32: do not use D14 as a temporary.

D14 is a callee-save register, which means we would need to
save it in the prologue, but at the point we're using it
the prologue has already been generated.

bug: 35977033
test: m ART_USE_VIXL_ARM_BACKEND=true test-art-target
Change-Id: Id7340ad9e87a9e527ce0989f45aae0b3a0963206

5 files changed, 110 insertions, 0 deletions

diff --git a/test/642-fp-callees/expected.txt b/test/642-fp-callees/expected.txt
new file mode 100644
index 0000000000..77a1486479
--- /dev/null
+++ b/test/642-fp-callees/expected.txt
@@ -0,0 +1,2 @@
+JNI_OnLoad called
+Done
diff --git a/test/642-fp-callees/fp_callees.cc b/test/642-fp-callees/fp_callees.cc
new file mode 100644
index 0000000000..600f9690eb
--- /dev/null
+++ b/test/642-fp-callees/fp_callees.cc
@@ -0,0 +1,71 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+#include "base/casts.h"
+#include "base/logging.h"
+#include "jni.h"
+
+namespace art {
+
+// Make the array volatile, which is apparently making the C compiler
+// use FP registers in the method below.
+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 };
+
+extern "C" JNIEXPORT void JNICALL Java_Main_holdFpTemporaries(JNIEnv* env, jclass cls) {
+  jmethodID mid = env->GetStaticMethodID(cls, "caller", "(IIJ)V");
+  CHECK(mid != nullptr);
+  // Load values from the arrays, which will be loaded in callee-save FP registers.
+  double a = array[0];
+  double b = array[1];
+  double c = array[2];
+  double d = array[3];
+  double e = array[4];
+  double f = array[5];
+  double g = array[6];
+  double h = array[7];
+  double i = array[8];
+  double j = array[9];
+  double k = array[10];
+  double l = array[11];
+  env->CallStaticVoidMethod(cls, mid, 1, 1, 1L);
+  // Load it in a temporary to please C compiler with bit_cast.
+  double temp = array[0];
+  CHECK_EQ(bit_cast<int64_t>(a), bit_cast<int64_t>(temp));
+  temp = array[1];
+  CHECK_EQ(bit_cast<int64_t>(b), bit_cast<int64_t>(temp));
+  temp = array[2];
+  CHECK_EQ(bit_cast<int64_t>(c), bit_cast<int64_t>(temp));
+  temp = array[3];
+  CHECK_EQ(bit_cast<int64_t>(d), bit_cast<int64_t>(temp));
+  temp = array[4];
+  CHECK_EQ(bit_cast<int64_t>(e), bit_cast<int64_t>(temp));
+  temp = array[5];
+  CHECK_EQ(bit_cast<int64_t>(f), bit_cast<int64_t>(temp));
+  temp = array[6];
+  CHECK_EQ(bit_cast<int64_t>(g), bit_cast<int64_t>(temp));
+  temp = array[7];
+  CHECK_EQ(bit_cast<int64_t>(h), bit_cast<int64_t>(temp));
+  temp = array[8];
+  CHECK_EQ(bit_cast<int64_t>(i), bit_cast<int64_t>(temp));
+  temp = array[9];
+  CHECK_EQ(bit_cast<int64_t>(j), bit_cast<int64_t>(temp));
+  temp = array[10];
+  CHECK_EQ(bit_cast<int64_t>(k), bit_cast<int64_t>(temp));
+  temp = array[11];
+  CHECK_EQ(bit_cast<int64_t>(l), bit_cast<int64_t>(temp));
+}
+
+}  // namespace art
diff --git a/test/642-fp-callees/info.txt b/test/642-fp-callees/info.txt
new file mode 100644
index 0000000000..d3e4bdac50
--- /dev/null
+++ b/test/642-fp-callees/info.txt
@@ -0,0 +1,2 @@
+Regression test for vixl32 backend, which used to incorrectly
+use D14 as a temporary register.
diff --git a/test/642-fp-callees/src/Main.java b/test/642-fp-callees/src/Main.java
new file mode 100644
index 0000000000..fa57c93eda
--- /dev/null
+++ b/test/642-fp-callees/src/Main.java
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2017 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.
+ */
+
+public class Main {
+  public static void main(String[] args) {
+    System.loadLibrary(args[0]);
+    holdFpTemporaries();
+    System.out.println("Done");
+  }
+
+  public static void caller(int a, int b, long c) {
+    $noinline$callee(a, b, c);
+  }
+
+  // This method is "no inline", in order to generate the
+  // bad floating point use at the call site.
+  public static void $noinline$callee(int a, int b, long c) {
+  }
+
+  public native static void holdFpTemporaries();
+}
diff --git a/test/Android.bp b/test/Android.bp
index 594cce2a6e..9911af0b03 100644
--- a/test/Android.bp
+++ b/test/Android.bp
@@ -336,6 +336,7 @@ cc_defaults {
         "596-monitor-inflation/monitor_inflation.cc",
         "597-deopt-new-string/deopt.cc",
         "626-const-class-linking/clear_dex_cache_types.cc",
+        "642-fp-callees/fp_callees.cc",
     ],
     shared_libs: [
         "libbacktrace",