From e395327a7c523e0736c1cb0bc5997f43232c3a47 Mon Sep 17 00:00:00 2001
From: Andrew Hsieh <andrewhsieh@google.com>
Date: Wed, 25 Jul 2012 15:39:00 -0700
Subject: [PATCH] Add comments about why "call" instead of "jump" is used.

Related CL: https://android-review.googlesource.com/#/c/38651

Change-Id: I425e06f08fda90501a686c7e437d4e70fc1e4a1b
---
 ndk/platforms/android-3/arch-arm/src/crtbegin_dynamic.S  | 1 +
 ndk/platforms/android-3/arch-arm/src/crtbegin_static.S   | 1 +
 ndk/platforms/android-9/arch-mips/src/crtbegin_dynamic.S | 1 +
 ndk/platforms/android-9/arch-mips/src/crtbegin_static.S  | 1 +
 4 files changed, 4 insertions(+)

diff --git a/ndk/platforms/android-3/arch-arm/src/crtbegin_dynamic.S b/ndk/platforms/android-3/arch-arm/src/crtbegin_dynamic.S
index ec6d482d8..c7c9f6d55 100644
--- a/ndk/platforms/android-3/arch-arm/src/crtbegin_dynamic.S
+++ b/ndk/platforms/android-3/arch-arm/src/crtbegin_dynamic.S
@@ -53,6 +53,7 @@ _start:
 	ldr	r2, =main
 	adr	r3, 1f
 	ldr	r4, =__libc_init
+# Use blx intead of bx so stack unwinding past __libc_init can terminate at _start
 	blx	r4
 	mov	r0, #0
 	bx	r0
diff --git a/ndk/platforms/android-3/arch-arm/src/crtbegin_static.S b/ndk/platforms/android-3/arch-arm/src/crtbegin_static.S
index d9d12a786..62ed4bbcc 100644
--- a/ndk/platforms/android-3/arch-arm/src/crtbegin_static.S
+++ b/ndk/platforms/android-3/arch-arm/src/crtbegin_static.S
@@ -53,6 +53,7 @@ _start:
 	ldr	r2, =main
 	adr	r3, 1f
 	ldr	r4, =__libc_init
+# Use blx intead of bx so stack unwinding past __libc_init can terminate at _start
 	blx	r4
 	mov	r0, #0
 	bx	r0
diff --git a/ndk/platforms/android-9/arch-mips/src/crtbegin_dynamic.S b/ndk/platforms/android-9/arch-mips/src/crtbegin_dynamic.S
index 28f8fd551..be42fb227 100644
--- a/ndk/platforms/android-9/arch-mips/src/crtbegin_dynamic.S
+++ b/ndk/platforms/android-9/arch-mips/src/crtbegin_dynamic.S
@@ -64,6 +64,7 @@ _start:
 	la	$a3, 1f
 	subu	$sp, 32
 	la	$t9, __libc_init
+# Use jalr intead of jr so stack unwinding past __libc_init can terminate at _start
 	jalr	$t9
 	move	$t9, $0
 	j	$t9
diff --git a/ndk/platforms/android-9/arch-mips/src/crtbegin_static.S b/ndk/platforms/android-9/arch-mips/src/crtbegin_static.S
index 893863c17..58bab827f 100644
--- a/ndk/platforms/android-9/arch-mips/src/crtbegin_static.S
+++ b/ndk/platforms/android-9/arch-mips/src/crtbegin_static.S
@@ -64,6 +64,7 @@ _start:
 	la	$a3, 1f
 	subu	$sp, 32
 	la	$t9, __libc_init
+# Use jalr intead of jr so stack unwinding past __libc_init can terminate at _start
 	jalr	$t9
 	move	$t9, $0
 	j	$t9