From ac7fd8737515818d8f089c4b8bc4f41126afae31 Mon Sep 17 00:00:00 2001
From: Raman Budny <budnyjj@gmail.com>
Date: Wed, 20 Nov 2019 17:08:12 +0300
Subject: [PATCH] Force alignment of generated JVM called functions.
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This CL effectively expands the zone of influence of
https://webrtc-review.googlesource.com/64160,
forcing 16-byte stack alignment of generated JNI methods
for the Android x86 platform.

Bug: webrtc:9085
Change-Id: Idc40c00ea3fb52dbbbeac7b58ceda2a9a44733d8
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/159928
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Reviewed-by: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29858}
---
 AUTHORS                                    | 3 ++-
 sdk/android/src/jni/jni_generator_helper.h | 9 +++++++++
 sdk/android/src/jni/jni_helpers.h          | 9 +++++++++
 3 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/AUTHORS b/AUTHORS
index d76148e8d2..df32313b3d 100644
--- a/AUTHORS
+++ b/AUTHORS
@@ -82,6 +82,8 @@ Michel Promonet <michel.promonet.1@gmail.com>
 Min Wang <mingewang@gmail.com>
 Ramprakash Jelari <ennajelari@gmail.com>
 CZ Theng <cz.theng@gmail.com>
+Miguel Paris <mparisdiaz@gmail.com>
+Raman Budny <budnyjj@gmail.com>
 
 &yet LLC <*@andyet.com>
 Agora IO <*@agora.io>
@@ -109,7 +111,6 @@ Videxio AS <*@videxio.com>
 Vidyo, Inc. <*@vidyo.com>
 Vonage Holdings Corp. <*@vonage.com>
 Wire Swiss GmbH <*@wire.com>
-Miguel Paris <mparisdiaz@gmail.com>
 Vewd Software AS <*@vewd.com>
 Highfive, Inc. <*@highfive.com>
 CoSMo Software Consulting, Pte Ltd <*@cosmosoftware.io>
diff --git a/sdk/android/src/jni/jni_generator_helper.h b/sdk/android/src/jni/jni_generator_helper.h
index e6d6f7ef15..a5497e1635 100644
--- a/sdk/android/src/jni/jni_generator_helper.h
+++ b/sdk/android/src/jni/jni_generator_helper.h
@@ -27,7 +27,16 @@
 
 #define BASE_EXPORT
 #define JNI_REGISTRATION_EXPORT __attribute__((visibility("default")))
+
+#if defined(WEBRTC_ARCH_X86)
+// Dalvik JIT generated code doesn't guarantee 16-byte stack alignment on
+// x86 - use force_align_arg_pointer to realign the stack at the JNI
+// boundary. crbug.com/655248
+#define JNI_GENERATOR_EXPORT \
+  __attribute__((force_align_arg_pointer)) extern "C" JNIEXPORT JNICALL
+#else
 #define JNI_GENERATOR_EXPORT extern "C" JNIEXPORT JNICALL
+#endif
 
 #define CHECK_EXCEPTION(jni)        \
   RTC_CHECK(!jni->ExceptionCheck()) \
diff --git a/sdk/android/src/jni/jni_helpers.h b/sdk/android/src/jni/jni_helpers.h
index 38b0d7edf4..7a2f27b99d 100644
--- a/sdk/android/src/jni/jni_helpers.h
+++ b/sdk/android/src/jni/jni_helpers.h
@@ -23,8 +23,17 @@
 
 // Convenience macro defining JNI-accessible methods in the org.webrtc package.
 // Eliminates unnecessary boilerplate and line-wraps, reducing visual clutter.
+#if defined(WEBRTC_ARCH_X86)
+// Dalvik JIT generated code doesn't guarantee 16-byte stack alignment on
+// x86 - use force_align_arg_pointer to realign the stack at the JNI
+// boundary. crbug.com/655248
+#define JNI_FUNCTION_DECLARATION(rettype, name, ...)                    \
+  __attribute__((force_align_arg_pointer)) extern "C" JNIEXPORT rettype \
+      JNICALL Java_org_webrtc_##name(__VA_ARGS__)
+#else
 #define JNI_FUNCTION_DECLARATION(rettype, name, ...) \
   extern "C" JNIEXPORT rettype JNICALL Java_org_webrtc_##name(__VA_ARGS__)
+#endif
 
 namespace webrtc {
 namespace jni {