linker: use UTIL_LISTIFY macro for dealing with .a files

Signed-off-by: Anas Nashif <anas.nashif@intel.com>

include/linker/linker-defs.h

@@ -21,6 +21,7 @@
 
 #include <toolchain.h>
 #include <linker/sections.h>
+#include <misc/util.h>
 
 /* include platform dependent linker-defs */
 #ifdef CONFIG_X86
@@ -102,9 +103,24 @@
 		__shell_cmd_end = .;
 
 #ifdef CONFIG_APPLICATION_MEMORY
-#define KERNEL_INPUT_SECTION(sect)	libzephyr.a (sect) kernel/lib.a (sect)
+
+#ifndef NUM_KERNEL_OBJECT_FILES
+#error "Expected NUM_KERNEL_OBJECT_FILES to be defined"
+#elif NUM_KERNEL_OBJECT_FILES > 19
+#error "Max supported kernel objects is 19."
+/* TODO: Using the preprocessor to do this was a mistake. Rewrite to
+   scale better. e.g. by aggregating the kernel objects into two
+   archives like KBuild did.*/
+#endif
+
+#define X(i, j)  KERNEL_OBJECT_FILE_##i (j)
+#define Y(i, j) *KERNEL_OBJECT_FILE_##i
+
+#define KERNEL_INPUT_SECTION(sect) \
+    UTIL_LISTIFY(NUM_KERNEL_OBJECT_FILES, X, sect)
 #define APP_INPUT_SECTION(sect)	\
-	*(EXCLUDE_FILE (*libzephyr.a *kernel/lib.a) sect)
+    *(EXCLUDE_FILE (UTIL_LISTIFY(NUM_KERNEL_OBJECT_FILES, Y, ~)) sect)
+
 #else
 #define KERNEL_INPUT_SECTION(sect)	*(sect)
 #define APP_INPUT_SECTION(sect)		*(sect)

include/misc/util.h

@@ -172,6 +172,136 @@ static inline s64_t arithmetic_shift_right(s64_t value, u8_t shift)
  */
 #define _IS_ENABLED3(ignore_this, val, ...) val
 
+/**
+ * Macros for doing code-generation with the preprocessor.
+ *
+ * Generally it is better to generate code with the preprocessor than
+ * to copy-paste code or to generate code with the build system /
+ * python script's etc.
+ *
+ * http://stackoverflow.com/a/12540675
+ */
+#define UTIL_EMPTY(...)
+#define UTIL_DEFER(...) __VA_ARGS__ UTIL_EMPTY()
+#define UTIL_OBSTRUCT(...) __VA_ARGS__ UTIL_DEFER(UTIL_EMPTY)()
+#define UTIL_EXPAND(...) __VA_ARGS__
+
+#define UTIL_EVAL(...)  UTIL_EVAL1(UTIL_EVAL1(UTIL_EVAL1(__VA_ARGS__)))
+#define UTIL_EVAL1(...) UTIL_EVAL2(UTIL_EVAL2(UTIL_EVAL2(__VA_ARGS__)))
+#define UTIL_EVAL2(...) UTIL_EVAL3(UTIL_EVAL3(UTIL_EVAL3(__VA_ARGS__)))
+#define UTIL_EVAL3(...) UTIL_EVAL4(UTIL_EVAL4(UTIL_EVAL4(__VA_ARGS__)))
+#define UTIL_EVAL4(...) UTIL_EVAL5(UTIL_EVAL5(UTIL_EVAL5(__VA_ARGS__)))
+#define UTIL_EVAL5(...) __VA_ARGS__
+
+#define UTIL_CAT(a, ...) UTIL_PRIMITIVE_CAT(a, __VA_ARGS__)
+#define UTIL_PRIMITIVE_CAT(a, ...) a##__VA_ARGS__
+
+#define UTIL_INC(x) UTIL_PRIMITIVE_CAT(UTIL_INC_, x)
+#define UTIL_INC_0 1
+#define UTIL_INC_1 2
+#define UTIL_INC_2 3
+#define UTIL_INC_3 4
+#define UTIL_INC_4 5
+#define UTIL_INC_5 6
+#define UTIL_INC_6 7
+#define UTIL_INC_7 8
+#define UTIL_INC_8 9
+#define UTIL_INC_9 10
+#define UTIL_INC_10 11
+#define UTIL_INC_11 12
+#define UTIL_INC_12 13
+#define UTIL_INC_13 14
+#define UTIL_INC_14 15
+#define UTIL_INC_15 16
+#define UTIL_INC_16 17
+#define UTIL_INC_17 18
+#define UTIL_INC_18 19
+#define UTIL_INC_19 19
+
+#define UTIL_DEC(x) UTIL_PRIMITIVE_CAT(UTIL_DEC_, x)
+#define UTIL_DEC_0 0
+#define UTIL_DEC_1 0
+#define UTIL_DEC_2 1
+#define UTIL_DEC_3 2
+#define UTIL_DEC_4 3
+#define UTIL_DEC_5 4
+#define UTIL_DEC_6 5
+#define UTIL_DEC_7 6
+#define UTIL_DEC_8 7
+#define UTIL_DEC_9 8
+#define UTIL_DEC_10 9
+#define UTIL_DEC_11 10
+#define UTIL_DEC_12 11
+#define UTIL_DEC_13 12
+#define UTIL_DEC_14 13
+#define UTIL_DEC_15 14
+#define UTIL_DEC_16 15
+#define UTIL_DEC_17 16
+#define UTIL_DEC_18 17
+#define UTIL_DEC_19 18
+
+#define UTIL_CHECK_N(x, n, ...) n
+#define UTIL_CHECK(...) UTIL_CHECK_N(__VA_ARGS__, 0,)
+
+#define UTIL_NOT(x) UTIL_CHECK(UTIL_PRIMITIVE_CAT(UTIL_NOT_, x))
+#define UTIL_NOT_0 ~, 1,
+
+#define UTIL_COMPL(b) UTIL_PRIMITIVE_CAT(UTIL_COMPL_, b)
+#define UTIL_COMPL_0 1
+#define UTIL_COMPL_1 0
+
+#define UTIL_BOOL(x) UTIL_COMPL(UTIL_NOT(x))
+
+#define UTIL_IIF(c) UTIL_PRIMITIVE_CAT(UTIL_IIF_, c)
+#define UTIL_IIF_0(t, ...) __VA_ARGS__
+#define UTIL_IIF_1(t, ...) t
+
+#define UTIL_IF(c) UTIL_IIF(UTIL_BOOL(c))
+
+#define UTIL_EAT(...)
+#define UTIL_EXPAND(...) __VA_ARGS__
+#define UTIL_WHEN(c) UTIL_IF(c)(UTIL_EXPAND, UTIL_EAT)
+
+#define UTIL_REPEAT(count, macro, ...)			    \
+	UTIL_WHEN(count)				    \
+	(						    \
+		UTIL_OBSTRUCT(UTIL_REPEAT_INDIRECT) ()	    \
+		(					    \
+			UTIL_DEC(count), macro, __VA_ARGS__ \
+		)					    \
+		UTIL_OBSTRUCT(macro)			    \
+		(					    \
+			UTIL_DEC(count), __VA_ARGS__	    \
+		)					    \
+	)
+#define UTIL_REPEAT_INDIRECT() UTIL_REPEAT
+
+/**
+ * Generates a sequence of code.
+ * Useful for generating code like;
+ *
+ * NRF_PWM0, NRF_PWM1, NRF_PWM2,
+ *
+ * @arg LEN: The length of the sequence. Must be defined and less than
+ * 20.
+ *
+ * @arg F(i, F_ARG): A macro function that accepts two arguments.
+ *  F is called repeatedly, the first argument
+ *  is the index in the sequence, and the second argument is the third
+ *  argument given to UTIL_LISTIFY.
+ *
+ * Example:
+ *
+ *    \#define FOO(i, _) NRF_PWM ## i ,
+ *    { UTIL_LISTIFY(PWM_COUNT, FOO) }
+ *    // The above two lines will generate the below:
+ *    { NRF_PWM0 , NRF_PWM1 , }
+ *
+ * @note Calling UTIL_LISTIFY with undefined arguments has undefined
+ * behaviour.
+ */
+#define UTIL_LISTIFY(LEN, F, F_ARG) UTIL_EVAL(UTIL_REPEAT(LEN, F, F_ARG))
+
 #ifdef __cplusplus
 }
 #endif