1 files changed, 0 insertions, 162 deletions
diff --git a/arch/riscv/usr/basics.c b/arch/riscv/usr/basics.c
deleted file mode 100644
index 1d822c3..0000000
--- a/arch/riscv/usr/basics.c
+++ /dev/null
@@ -1,162 +0,0 @@
-#include <assert.h>
-#include <stdbool.h>
-#include <stdio.h>
-#include <stdint.h>
-#include <string.h>
-
-/*
- * Returns the factorial for the given unsigned 64-bit integer.
- *
- * Implemented in factorial.S
- */
-int factorial(uint64_t n);
-
-void test_factorial(void)
-{
-	assert(factorial(0) == 0);
-	assert(factorial(1) == 1);
-	assert(factorial(2) == 2);
-	assert(factorial(3) == 6);
-	assert(factorial(4) == 24);
-
-	printf("factorial:\t\tOK\n");
-}
-
-/*
- * Returns a pointer with the same given string but reversed. Note that the
- * string cannot be in read-only space since the reversal is done in-place.
- *
- * Implemented in string.S
- */
-char *reverse_string(char *str);
-
-void test_reverse_string(void)
-{
-	assert(reverse_string(NULL) == NULL);
-	assert(strlen(reverse_string("")) == 0);
-
-	char s1[] = "This is a string.";
-	assert(strcmp(reverse_string(s1), ".gnirts a si sihT") == 0);
-
-	char s2[] = ".";
-	assert(strcmp(reverse_string(s2), ".") == 0);
-
-	printf("reverse_string:\t\tOK\n");
-}
-
-/*
- * Returns true if the given string is a palindrome, false otherwise.
- *
- * Implemented in string.S
- */
-bool is_palindrome(char *str);
-
-void test_is_palindrome(void)
-{
-	assert(is_palindrome(NULL) == 0);
-	assert(is_palindrome("") == 0);
-	assert(is_palindrome("aba") == 1);
-	assert(is_palindrome("aaa") == 1);
-	assert(is_palindrome("This is a a si sihT") == 1);
-
-	printf("is_palindrome:\t\tOK\n");
-}
-
-/*
- * This function computes the following: ((a + b) * b) + b. Don't try to make
- * sense of it, that's the computation I ended up while messing with RISC-V
- * floating point instructions. Anyways, with this in mind, it will return if
- * the computed value is greater than 10.
- *
- * Implemented in float.S
- */
-bool greater_than_ten(double a, uint64_t b);
-
-void test_greater_than_ten(void)
-{
-	assert(!greater_than_ten(2.3, 1)); // 4.3
-	assert(greater_than_ten(2.3, 2)); // 10.6
-
-	printf("greater_than_ten:\tOK\n");
-}
-
-/*
- * Atomically add the integer pointed by `a` with the given `value`.
- * this is a function, I've checked that the assembly produced by GCC on a
- * decent optimization level actually inlines this.
- */
-static inline void atomic_add(uint64_t *a, uint64_t value)
-{
-	/*
-	 * The execution is a mere `amoadd` instruction, but it will set on `t0` the
-	 * result. If it fails (e.g. the address was already being used), then `t0 =
-	 * 0` and `beqz` will instruct it to try again.
-	 *
-	 * Note that on the board I'm using the 'Zawrs' extension is not available.
-	 * Otherwise I could have re-arranged to code to something like this:
-	 *
-	 *     amoadd.d t0, %1, %0
-	 *     bnez t0, .Latomic_add_done
-	 *     wrs.nto
-	 *  .Latomic_add_done:
-	 *
-	 * This is an extra instruction but it saves on power if the memory address
-	 * happens to be used at access time.
-	 *
-	 * As for the 'A' RISC-V specific constraint, it means "An address that is
-	 * held in a general-purpose register". GCC will then do the magic and
-	 * convert it to `amoadd.d t0, a1, (a0)` or something like that. Note that
-	 * we have to pass the '+' constraint modifier because the address will be
-	 * both read and written atomically.
-	 *
-	 * See: https://gcc.gnu.org/onlinedocs/gcc/Machine-Constraints.html.
-	 */
-	asm volatile(".Latomic_add_retry:\n\t"
-				 "amoadd.d t0, %1, %0\n\t"
-				 "beqz t0, .Latomic_add_retry"
-				 : "+A"(*a)
-				 : "r"(value)
-				 : "t0", "memory");
-}
-
-void test_atomic_add(void)
-{
-	uint64_t i = 4;
-
-	atomic_add(&i, 0);
-	assert(i == 4);
-
-	atomic_add(&i, 2);
-	assert(i == 6);
-
-	printf("atomic_add:\t\tOK\n");
-}
-
-extern int mstrcmp(const char *s1, const char *s2);
-
-void test_mstrcmp(void)
-{
-	char *strings[] = {
-		"hello", "", "iello", "helloa", "contammusaaquellhomedegranarditquetantissimerra",
-	};
-
-	for (uint64_t i = 0; i < 1000000000; i++) {
-		assert(mstrcmp(strings[0], strings[0]) == 0);
-		assert(mstrcmp(strings[0], strings[1]) > 0);
-		assert(mstrcmp(strings[0], strings[2]) < 0);
-		assert(mstrcmp(strings[0], strings[3]) < 0);
-		assert(mstrcmp(strings[0], strings[4]) > 0);
-	}
-
-	printf("mstrcmp:\t\tOK\n");
-}
-
-int main()
-{
-	test_factorial();
-	test_reverse_string();
-	test_is_palindrome();
-	test_greater_than_ten();
-	test_atomic_add();
-	test_mstrcmp();
-}