Move non-function-specific macro outside of function definition
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/library/constant_time_impl.h b/library/constant_time_impl.h
index 111b9af..ab39397 100644
--- a/library/constant_time_impl.h
+++ b/library/constant_time_impl.h
@@ -115,6 +115,28 @@
#endif
}
+/*
+ * Selecting unified syntax is needed for gcc, and harmless on clang.
+ *
+ * This is needed because on Thumb 1, condition flags are always set, so
+ * e.g. "negs" is supported but "neg" is not (on Thumb 2, both exist).
+ *
+ * Under Thumb 1 unified syntax, only the "negs" form is accepted, and
+ * under divided syntax, only the "neg" form is accepted. clang only
+ * supports unified syntax.
+ *
+ * On Thumb 2 and Arm, both compilers are happy with the "s" suffix,
+ * although we don't actually care about setting the flags.
+ *
+ * For gcc, restore divided syntax afterwards - otherwise old versions of gcc
+ * seem to apply unified syntax globally, which breaks other asm code.
+ */
+#if !defined(__clang__)
+#define RESTORE_ASM_SYNTAX ".syntax divided \n\t"
+#else
+#define RESTORE_ASM_SYNTAX
+#endif
+
/* Convert a number into a condition in constant time. */
static inline mbedtls_ct_condition_t mbedtls_ct_bool(mbedtls_ct_uint_t x)
{
@@ -140,28 +162,6 @@
return (mbedtls_ct_condition_t) x;
#elif defined(MBEDTLS_CT_ARM_ASM) && defined(MBEDTLS_CT_SIZE_32)
uint32_t s;
- /*
- * Selecting unified syntax is needed for gcc, and harmless on clang.
- *
- * This is needed because on Thumb 1, condition flags are always set, so
- * e.g. "negs" is supported but "neg" is not (on Thumb 2, both exist).
- *
- * Under Thumb 1 unified syntax, only the "negs" form is accepted, and
- * under divided syntax, only the "neg" form is accepted. clang only
- * supports unified syntax.
- *
- * On Thumb 2 and Arm, both compilers are happy with the "s" suffix,
- * although we don't actually care about setting the flags.
- *
- * For gcc, restore divided syntax afterwards - otherwise old versions of gcc
- * seem to apply unified syntax globally, which breaks other asm code.
- */
-#if !defined(__clang__)
-#define RESTORE_ASM_SYNTAX ".syntax divided \n\t"
-#else
-#define RESTORE_ASM_SYNTAX
-#endif
-
asm volatile (".syntax unified \n\t"
"negs %[s], %[x] \n\t"
"orrs %[x], %[x], %[s] \n\t"