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| author | Szabolcs Nagy <nsz@port70.net> | 2018-08-24 23:11:59 +0000 |
|---|---|---|
| committer | Rich Felker <dalias@aerifal.cx> | 2018-08-28 17:08:14 -0400 |
| commit | 056f9d818eaf1dbe9e9d63b64b109fd9b608fa36 (patch) | |
| tree | c6b94b438e17f8618275279f62fc56c30052408a | |
| parent | cdbbcfb8f5d748f17694a5cc404af4b9381ff95f (diff) | |
| download | musl-056f9d818eaf1dbe9e9d63b64b109fd9b608fa36.tar.gz | |
rewrite __aeabi_read_tp in asm
__aeabi_read_tp used to call c code, but that was incorrect as the
arm runtime abi specifies special pcs for this function: it is only
allowed to clobber r0, ip, lr and cpsr.
maintainer's note: the old code explicitly saved and restored all
general-purpose registers which are call-clobbered in the normal
calling convention, so it's unlikely that any real-world compilers
produced code that could break. however theoretically they could have
chosen to use floating point registers, in which case the caller's
values of those registers would be clobbered.
| -rw-r--r-- | src/thread/arm/__aeabi_read_tp.s | 10 | ||||
| -rw-r--r-- | src/thread/arm/__aeabi_read_tp_c.c | 8 |
2 files changed, 6 insertions, 12 deletions
diff --git a/src/thread/arm/__aeabi_read_tp.s b/src/thread/arm/__aeabi_read_tp.s index 9d0cd311..2585620c 100644 --- a/src/thread/arm/__aeabi_read_tp.s +++ b/src/thread/arm/__aeabi_read_tp.s @@ -2,7 +2,9 @@ .global __aeabi_read_tp .type __aeabi_read_tp,%function __aeabi_read_tp: - push {r1,r2,r3,lr} - bl __aeabi_read_tp_c - pop {r1,r2,r3,lr} - bx lr + ldr r0,1f + add r0,r0,pc + ldr r0,[r0] +2: bx r0 + .align 2 +1: .word __a_gettp_ptr - 2b diff --git a/src/thread/arm/__aeabi_read_tp_c.c b/src/thread/arm/__aeabi_read_tp_c.c deleted file mode 100644 index 0c56d613..00000000 --- a/src/thread/arm/__aeabi_read_tp_c.c +++ /dev/null @@ -1,8 +0,0 @@ -#include "pthread_impl.h" -#include <stdint.h> - -__attribute__((__visibility__("hidden"))) -void *__aeabi_read_tp_c(void) -{ - return TP_ADJ(__pthread_self()); -} |