Remove the bogus exit status from _exit_with_stack_teardown.

It should always be 0, and there's no reason to pass a constant in as
an argument.

Change-Id: I92ac59b718a18e298bd7c52821af447f9181ca2a

libc/arch-aarch64/bionic/_exit_with_stack_teardown.S

@@ -26,17 +26,15 @@
  * SUCH DAMAGE.
  */
 
-#include <asm/unistd.h>
-#include <machine/asm.h>
+#include <private/bionic_asm.h>
 
-// void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status)
+// void _exit_with_stack_teardown(void* stackBase, size_t stackSize)
 ENTRY(_exit_with_stack_teardown)
-  mov     w28, w2
   mov w8, __NR_munmap
   svc #0
   // If munmap failed, we ignore the failure and exit anyway.
 
-  sxtw    x0, w28
+  mov x0, #0
   mov w8, __NR_exit
   svc #0
   // The exit syscall does not return.

libc/arch-arm/bionic/_exit_with_stack_teardown.S

@@ -26,17 +26,15 @@
  * SUCH DAMAGE.
  */
 
-#include <machine/asm.h>
-#include <asm/unistd.h>
+#include <private/bionic_asm.h>
 
-// void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status)
+// void _exit_with_stack_teardown(void* stackBase, size_t stackSize)
 ENTRY(_exit_with_stack_teardown)
-    mov     lr, r2
   ldr r7, =__NR_munmap
   swi #0
   // If munmap failed, we ignore the failure and exit anyway.
 
-    mov     r0, lr
+  mov r0, #0
   ldr r7, =__NR_exit
   swi #0
   // The exit syscall does not return.

libc/arch-mips/bionic/_exit_with_stack_teardown.S

@@ -30,21 +30,19 @@
 
 	.text
 
-// void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status)
+// void _exit_with_stack_teardown(void* stackBase, size_t stackSize)
 
 	.type	_exit_with_stack_teardown, @function
 	.global	_exit_with_stack_teardown
 	.align	4
 	.ent	_exit_with_stack_teardown
 _exit_with_stack_teardown:
-	move	$s0,$a2		/* preserve status for exit() call */
-
-	li	$v0,__NR_munmap
+	li	$v0, __NR_munmap
 	syscall
 	// If munmap failed, we ignore the failure and exit anyway.
 
-	move	$a0,$s0
-	li	$v0,__NR_exit
+	move	$a0, 0
+	li	$v0, __NR_exit
 	syscall
         // The exit syscall does not return.
 	.end	_exit_with_stack_teardown

libc/arch-x86/bionic/_exit_with_stack_teardown.S

@@ -1,20 +1,15 @@
-#include <asm/unistd.h>
-#include <machine/asm.h>
+#include <private/bionic_asm.h>
 
-// void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status)
+// void _exit_with_stack_teardown(void* stackBase, size_t stackSize)
 ENTRY(_exit_with_stack_teardown)
   // We can trash registers because this function never returns.
-    // We can also take advantage of the fact that the linux syscall trap
-    // handler saves all the registers, so we don't need a stack to keep
-    // the status argument for exit while doing the munmap.
   mov 4(%esp), %ebx             // stackBase
   mov 8(%esp), %ecx             // stackSize
-    mov     12(%esp), %edx            // Also copy 'status' off the stack we're about to unmap.
   mov $__NR_munmap, %eax
   int $0x80
   // If munmap failed, we ignore the failure and exit anyway.
 
-    mov     %edx, %ebx                // status
+  mov $0, %ebx                  // status
   movl $__NR_exit, %eax
   int $0x80
   // The exit syscall does not return.

libc/arch-x86_64/bionic/_exit_with_stack_teardown.S

@@ -26,19 +26,15 @@
  * SUCH DAMAGE.
  */
 
-#include <asm/unistd.h>
-#include <machine/asm.h>
+#include <private/bionic_asm.h>
 
-// void _exit_with_stack_teardown(void* stackBase, size_t stackSize, int status)
+// void _exit_with_stack_teardown(void* stackBase, size_t stackSize)
 ENTRY(_exit_with_stack_teardown)
-    // We take advantage of the fact that the linux syscall trap
-    // handler saves all the registers, so we don't need to save
-    // the status argument for exit(2) while doing the munmap(2).
   mov $__NR_munmap, %eax
   syscall
   // If munmap failed, we ignore the failure and exit anyway.
 
-    mov     %rdx, %rdi        // status
+  mov $0, %rdi
   mov $__NR_exit, %eax
   syscall
   // The exit syscall does not return.

libc/bionic/pthread_exit.cpp

@@ -34,7 +34,7 @@
 
 #include "pthread_internal.h"
 
-extern "C" void _exit_with_stack_teardown(void*, size_t, int);
+extern "C" void _exit_with_stack_teardown(void*, size_t);
 extern "C" void __exit(int);
 extern "C" int __set_tid_address(int*);
 
@@ -125,7 +125,7 @@ void pthread_exit(void* return_value) {
     sigfillset(&mask);
     sigprocmask(SIG_SETMASK, &mask, NULL);
 
-    _exit_with_stack_teardown(stack_base, stack_size, 0);
+    _exit_with_stack_teardown(stack_base, stack_size);
   }
 
   // NOTREACHED, but we told the compiler this function is noreturn, and it doesn't believe us.