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authorStefan Agner <stefan@agner.ch>2019-03-23 12:10:44 +0100
committerRussell King <rmk+kernel@armlinux.org.uk>2019-04-23 17:20:52 +0100
commitfe09d9c641f2064390afabdf436fe09b35e075ff (patch)
treef905c12b7edcc44017eeee55e2fc4a4b28848a67 /arch/arm/include/asm/uaccess.h
parenta6c9e96bf86b8aa86d8696b7887e52c2e95bac0f (diff)
ARM: 8852/1: uaccess: use unified assembler language syntax
Convert the conditional infix to a postfix to make sure this inline assembly is unified syntax. Since gcc assumes non-unified syntax when emitting ARM instructions, make sure to define the syntax as unified. This allows to use LLVM's integrated assembler. Additionally, for GCC ".syntax unified" for inline assembly. When compiling non-Thumb2 GCC always emits a ".syntax divided" at the beginning of the inline assembly which makes the assembler fail. Since GCC 5 there is the -masm-syntax-unified GCC option which make GCC assume unified syntax asm and hence emits ".syntax unified" even in ARM mode. However, the option is broken since GCC version 6 (see GCC PR88648 [1]). Work around by adding ".syntax unified" as part of the inline assembly. [0] https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html#index-masm-syntax-unified [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88648 Signed-off-by: Stefan Agner <stefan@agner.ch> Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Diffstat (limited to 'arch/arm/include/asm/uaccess.h')
-rw-r--r--arch/arm/include/asm/uaccess.h3
1 files changed, 2 insertions, 1 deletions
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h
index dff49845eb87..d49ce8f48be3 100644
--- a/arch/arm/include/asm/uaccess.h
+++ b/arch/arm/include/asm/uaccess.h
@@ -112,10 +112,11 @@ static inline void __user *__uaccess_mask_range_ptr(const void __user *ptr,
unsigned long tmp;
asm volatile(
+ " .syntax unified\n"
" sub %1, %3, #1\n"
" subs %1, %1, %0\n"
" addhs %1, %1, #1\n"
- " subhss %1, %1, %2\n"
+ " subshs %1, %1, %2\n"
" movlo %0, #0\n"
: "+r" (safe_ptr), "=&r" (tmp)
: "r" (size), "r" (current_thread_info()->addr_limit)