From e3a7c6a9da89b96f2b7026e71d8e3beb1f5bd140 Mon Sep 17 00:00:00 2001 From: TC Wan Date: Fri, 17 Dec 2010 09:58:02 +0800 Subject: store user mode next instruction address in r15 slot Keep Next Instruction Address in User Mode R15 stack frame slot. --- Debugger/undef_handler.S | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'Debugger/undef_handler.S') diff --git a/Debugger/undef_handler.S b/Debugger/undef_handler.S index 61b8a5d..34154f7 100644 --- a/Debugger/undef_handler.S +++ b/Debugger/undef_handler.S @@ -35,7 +35,8 @@ undef_handler: On entry, LR_undef points to one instruction past the UNDEF instruction */ ldr sp, =__debugger_stack__ - stmfd sp, {r0-r15}^ /* Save workspace, user mode's pc via 'S' flag */ + stmfd sp, {r0-r15}^ /* Save workspace, user mode's pc via 'S' flag, R15: placeholder */ + str lr, [sp, #-4] /* Keep User's Next Instr Pointer (in UNDEF SP) in user mode R15 */ sub sp, sp, #(4*16) /* Need to manually update SP(undef) */ mrs r1, spsr /* Copy SPSR to r0 */ tst r1, #CPSR_THUMB /* Check for Thumb Mode */ -- cgit v1.2.3