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Subject[PATCH 1/2] tile: fix put_user sparse errors
Use x86's __inttype macro instead of using the typeof(x-x) trick to
generate a suitable integer size type. This avoids a sparse warning
when examining the x-x type with a bitwise type.

Signed-off-by: Chris Metcalf <cmetcalf@ezchip.com>
---
arch/tile/include/asm/uaccess.h | 18 +++++++++---------
1 file changed, 9 insertions(+), 9 deletions(-)

diff --git a/arch/tile/include/asm/uaccess.h b/arch/tile/include/asm/uaccess.h
index b6cde3209b96..b81b24a8489b 100644
--- a/arch/tile/include/asm/uaccess.h
+++ b/arch/tile/include/asm/uaccess.h
@@ -114,14 +114,14 @@ struct exception_table_entry {
extern int fixup_exception(struct pt_regs *regs);

/*
+ * This is a type: either unsigned long, if the argument fits into
+ * that type, or otherwise unsigned long long.
+ */
+#define __inttype(x) \
+ __typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))
+
+/*
* Support macros for __get_user().
- *
- * Implementation note: The "case 8" logic of casting to the type of
- * the result of subtracting the value from itself is basically a way
- * of keeping all integer types the same, but casting any pointers to
- * ptrdiff_t, i.e. also an integer type. This way there are no
- * questionable casts seen by the compiler on an ILP32 platform.
- *
* Note that __get_user() and __put_user() assume proper alignment.
*/

@@ -178,7 +178,7 @@ extern int fixup_exception(struct pt_regs *regs);
"9:" \
: "=r" (ret), "=r" (__a), "=&r" (__b) \
: "r" (ptr), "i" (-EFAULT)); \
- (x) = (__typeof(x))(__typeof((x)-(x))) \
+ (x) = (__force __typeof(x))(__inttype(x)) \
(((u64)__hi32(__a, __b) << 32) | \
__lo32(__a, __b)); \
})
@@ -246,7 +246,7 @@ extern int __get_user_bad(void)
#define __put_user_4(x, ptr, ret) __put_user_asm(sw, x, ptr, ret)
#define __put_user_8(x, ptr, ret) \
({ \
- u64 __x = (__typeof((x)-(x)))(x); \
+ u64 __x = (__force __inttype(x))(x); \
int __lo = (int) __x, __hi = (int) (__x >> 32); \
asm volatile("1: { sw %1, %2; addi %0, %1, 4 }\n" \
"2: { sw %0, %3; movei %0, 0 }\n" \
--
2.1.2


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