[PATCH] ARM: alignment: Use is_wide_instruction() to check wide instruction

From: Yingjoe Chen
Date: Fri Apr 10 2015 - 10:06:04 EST



I first notice the comment is incorrect, then I realize there's another
macro which do exactly the same thing.
Tested with hand written userspace program with a few wide instructions
to make sure this still work as expect.

8<-------------------------------------------------
do_alignment() is using locally added IS_T32() macro to check if an
instruction is a Thumb-2 32 bit instruction. The macro
is_wide_instruction() is doing the same thing, with slightly faster
implementation.
Change to use is_wide_instruction() in do_alignment() and remove
IS_T32().

Signed-off-by: Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx>
---
arch/arm/mm/alignment.c | 6 +-----
1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/arm/mm/alignment.c b/arch/arm/mm/alignment.c
index 2c0c541..f8e82f5 100644
--- a/arch/arm/mm/alignment.c
+++ b/arch/arm/mm/alignment.c
@@ -71,10 +71,6 @@

#define BAD_INSTR 0xdeadc0de

-/* Thumb-2 32 bit format per ARMv7 DDI0406A A6.3, either f800h,e800h,f800h */
-#define IS_T32(hi16) \
- (((hi16) & 0xe000) == 0xe000 && ((hi16) & 0x1800))
-
static unsigned long ai_user;
static unsigned long ai_sys;
static void *ai_sys_last_pc;
@@ -770,7 +766,7 @@ do_alignment(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
tinstr = __mem_to_opcode_thumb16(tinstr);
if (!fault) {
if (cpu_architecture() >= CPU_ARCH_ARMv7 &&
- IS_T32(tinstr)) {
+ is_wide_instruction(tinstr)) {
/* Thumb-2 32-bit */
u16 tinst2 = 0;
fault = probe_kernel_address(ptr + 1, tinst2);
--
1.8.1.1.dirty

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