armclang: adding toolchain/armclang.h header

The armclang.h includes the toolchain/llvm.h header.

Also it redifines the __GENERIC_SECTION and Z_GENERIC_SECTION so that
they includes the `used` attribute which is needed by armlink.

Signed-off-by: Torsten Rasmussen <[email protected]>

Author: tejlmand

include/toolchain.h

@@ -42,6 +42,8 @@
 #include <toolchain/xcc.h>
 #elif defined(__CCAC__)
 #include <toolchain/mwdt.h>
+#elif defined(__ARMCOMPILER_VERSION)
+#include <toolchain/armclang.h>
 #elif defined(__llvm__)
 #include <toolchain/llvm.h>
 #elif defined(__GNUC__) || (defined(_LINKER) && defined(__GCC_LINKER_CMD__))

include/toolchain/armclang.h

@@ -0,0 +1,23 @@
+/*
+ * Copyright (c) 2021 Nordic Semiconductor ASA
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef ZEPHYR_INCLUDE_TOOLCHAIN_ARMCLANG_H_
+#define ZEPHYR_INCLUDE_TOOLCHAIN_ARMCLANG_H_
+
+
+#include <toolchain/llvm.h>
+
+/*
+ * To reuse as much as possible from the llvm.h header we only redefine the
+ * __GENERIC_SECTION and Z_GENERIC_SECTION macros here to include the `used` keyword.
+ */
+#undef __GENERIC_SECTION
+#undef Z_GENERIC_SECTION
+
+#define __GENERIC_SECTION(segment) __attribute__((section(STRINGIFY(segment)), used))
+#define Z_GENERIC_SECTION(segment) __GENERIC_SECTION(segment)
+
+#endif /* ZEPHYR_INCLUDE_TOOLCHAIN_ARMCLANG_H_ */