From e0e8ae754cc7653fcff489a0e229adbbb49fde6c Mon Sep 17 00:00:00 2001 From: Patrick Oppenlander Date: Thu, 1 Aug 2019 14:34:59 +1000 Subject: in arm cancellation point asm, don't unnecessarily preserve link register The only reason we needed to preserve the link register was because we were using a branch-link instruction to branch to __cp_cancel. Replacing this with a branch means we can avoid the save/restore as the link register is no longer modified. --- src/thread/arm/syscall_cp.s | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/src/thread/arm/syscall_cp.s b/src/thread/arm/syscall_cp.s index a5730c08..e607dd42 100644 --- a/src/thread/arm/syscall_cp.s +++ b/src/thread/arm/syscall_cp.s @@ -11,19 +11,19 @@ .type __syscall_cp_asm,%function __syscall_cp_asm: mov ip,sp - stmfd sp!,{r4,r5,r6,r7,lr} + stmfd sp!,{r4,r5,r6,r7} __cp_begin: ldr r0,[r0] cmp r0,#0 - blne __cp_cancel + bne __cp_cancel mov r7,r1 mov r0,r2 mov r1,r3 ldmfd ip,{r2,r3,r4,r5,r6} svc 0 __cp_end: - ldmfd sp!,{r4,r5,r6,r7,lr} + ldmfd sp!,{r4,r5,r6,r7} bx lr __cp_cancel: - ldmfd sp!,{r4,r5,r6,r7,lr} + ldmfd sp!,{r4,r5,r6,r7} b __cancel -- cgit v1.2.1