[PATCH 12/16] ARM: Simplify condition checks in swp_handler

[Marc Zyngier]

We now check the validity of the condition code before calling
the UNDEF handlers, so we can simplify swp_handler by only
checking for ARM_OPCODE_CONDTEST_UNCOND, which indicates that
this is not a SWP instruction.

Signed-off-by: Marc Zyngier <marc.zyng...@arm.com>
---
 arch/arm/kernel/swp_emulate.c | 15 ++-------------
 1 file changed, 2 insertions(+), 13 deletions(-)

diff --git a/arch/arm/kernel/swp_emulate.c b/arch/arm/kernel/swp_emulate.c
index 3bda08bee674..2683c559e0ff 100644
--- a/arch/arm/kernel/swp_emulate.c
+++ b/arch/arm/kernel/swp_emulate.c
@@ -179,20 +179,9 @@ static int swp_handler(struct pt_regs *regs, unsigned int 
instr)
 
        perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, regs->ARM_pc);
 
-       res = arm_check_condition(instr, regs->ARM_cpsr);
-       switch (res) {
-       case ARM_OPCODE_CONDTEST_PASS:
-               break;
-       case ARM_OPCODE_CONDTEST_FAIL:
-               /* Condition failed - return to next instruction */
-               regs->ARM_pc += 4;
-               return 0;
-       case ARM_OPCODE_CONDTEST_UNCOND:
-               /* If unconditional encoding - not a SWP, undef */
+       /* If unconditional encoding - not a SWP, undef */
+       if (arm_check_condition(instr, regs->ARM_cpsr) == 
ARM_OPCODE_CONDTEST_UNCOND)
                return -EFAULT;
-       default:
-               return -EINVAL;
-       }
 
        if (current->pid != previous_pid) {
                pr_debug("\"%s\" (%ld) uses deprecated SWP{B} instruction\n",
-- 
2.11.0