The current arch implementation of memcpy cannot be called from thumb code, because it does not use bx instructions on return. This patch addresses that. Note, that this patch does not touch the hot loop of memcpy, so performance is not affected.
Tested on MXS (arm926ejs) with and without thumb-mode enabled.
Signed-off-by: Klaus Goger klaus.goger@theobroma-systems.com Signed-off-by: Christoph Muellner christoph.muellner@theobroma-systems.com
---
Changes in v3: None Changes in v2: - added memcpy patch to the series
arch/arm/lib/memcpy.S | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/arch/arm/lib/memcpy.S b/arch/arm/lib/memcpy.S index 588b3f8971..9e9a193c2a 100644 --- a/arch/arm/lib/memcpy.S +++ b/arch/arm/lib/memcpy.S @@ -62,7 +62,7 @@ #endif ENTRY(memcpy) cmp r0, r1 - moveq pc, lr + bxeq lr
enter r4, lr
@@ -150,7 +150,8 @@ ENTRY(memcpy) str1b r0, r4, cs, abort=21f str1b r0, ip, cs, abort=21f
- exit r4, pc + exit r4, lr + bx lr
9: rsb ip, ip, #4 cmp ip, #2 @@ -259,7 +260,8 @@ ENTRY(memcpy) .endm
.macro copy_abort_end - ldmfd sp!, {r4, pc} + ldmfd sp!, {r4, lr} + bx lr .endm
ENDPROC(memcpy)