From 7684ddaf52dcd793d118eab22c8ffafc0b955373 Mon Sep 17 00:00:00 2001 From: Fernando Nasser Date: Thu, 23 Mar 2000 20:19:13 +0000 Subject: Thu Mar 22 14:57:00 2000 Fernando Nasser * libc/sys/arm/syscalls.c (do_AngelSWI): Prevent registers with valid information to be clobbered by an Angel C library support syscall. --- newlib/libc/sys/arm/syscalls.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'newlib/libc') diff --git a/newlib/libc/sys/arm/syscalls.c b/newlib/libc/sys/arm/syscalls.c index fb190e11b..2fb2ae1fd 100644 --- a/newlib/libc/sys/arm/syscalls.c +++ b/newlib/libc/sys/arm/syscalls.c @@ -103,8 +103,13 @@ do_AngelSWI (int reason, void * arg) asm volatile ("mov r0, %1; mov r1, %2; swi %a3; mov %0, r0" : "=r" (value) /* Outputs */ : "r" (reason), "r" (arg), "i" (AngelSWI) /* Inputs */ - : "r0", "r1", "lr" + : "r0", "r1", "r2", "r3", "ip", "lr", "memory" /* Clobbers r0 and r1, and lr if in supervisor mode */); + /* Accordingly to page 13-77 of ARM DUI 0040D other registers + can also be clobbered. Some memory positions may also be + changed by a system call, so they should not be kept in + registers. Note: we are assuming the manual is right and + Angel is respecting the APCS */ return value; } #endif /* ARM_RDI_MONITOR */ -- cgit v1.2.3