d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Ensure we align the stack to 8 bytes in rtld.

Browse Source 
This is not strictly required with the current ABI but will be when we
switch to the ARM EABI. The aapcs requires the stack to be 4 byte aligned
at all times and 8 byte aligned when calling a public subroutine where the
current ABI only requires sp to be a multiple of 4.
This commit is contained in:
Andrew Turner 2012-08-04 05:30:20 +00:00
parent d0ec68d41c
commit 782b05f96b
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=239031
1 changed files with 4 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
libexec/rtld-elf/arm/rtld_start.S
View File

@ -37,6 +37,8 @@ __FBSDID("$FreeBSD$");
.globl .rtld_start
.type .rtld_start,%function
.rtld_start:
mov r6, sp /* save the stack pointer */
bic sp, sp, #7 /* align the stack pointer */
sub sp, sp, #8 /* make room for obj_main & exit proc */
mov r4, r0 /* save ps_strings */
ldr sl, .L2
@ -52,13 +54,13 @@ __FBSDID("$FreeBSD$");
bl _rtld_relocate_nonplt_self
mov r1, sp
add r2, sp, #4
add r0, sp, #8
mov r0, r6 /* load the sp the kernel gave us */
bl _rtld /* call the shared loader */
mov r3, r0 /* save entry point */
ldr r2, [sp, #0] /* r2 = cleanup */
ldr r1, [sp, #4] /* r1 = obj_main */
add sp, sp, #8 /* restore stack */
mov sp, r6 /* restore stack */
mov r0, r4 /* restore ps_strings */
mov pc, r3 /* jump to the entry point */
.L2: