Add mod function to core.

The `mod` function is a pair function with `%`, or te remainder
function and is distinct from it. This is taken from common lisp.

src/core/asm.c

@@ -108,6 +108,7 @@ static const JanetInstructionDef janet_ops[] = {
     {"mkstu", JOP_MAKE_STRUCT},
     {"mktab", JOP_MAKE_TABLE},
     {"mktup", JOP_MAKE_TUPLE},
+    {"mod", JOP_MODULO},
     {"movf", JOP_MOVE_FAR},
     {"movn", JOP_MOVE_NEAR},
     {"mul", JOP_MULTIPLY},
@@ -121,6 +122,7 @@ static const JanetInstructionDef janet_ops[] = {
     {"pusha", JOP_PUSH_ARRAY},
     {"put", JOP_PUT},
     {"puti", JOP_PUT_INDEX},
+    {"rem", JOP_REMAINDER},
     {"res", JOP_RESUME},
     {"ret", JOP_RETURN},
     {"retn", JOP_RETURN_NIL},

src/core/bytecode.c

@@ -41,6 +41,8 @@ enum JanetInstructionType janet_instructions[JOP_INSTRUCTION_COUNT] = {
     JINT_SSS, /* JOP_MULTIPLY, */
     JINT_SSI, /* JOP_DIVIDE_IMMEDIATE, */
     JINT_SSS, /* JOP_DIVIDE, */
+    JINT_SSS, /* JOP_MODULO, */
+    JINT_SSS, /* JOP_REMAINDER, */
     JINT_SSS, /* JOP_BAND, */
     JINT_SSS, /* JOP_BOR, */
     JINT_SSS, /* JOP_BXOR, */

src/core/cfuns.c

@@ -115,6 +115,12 @@ static JanetSlot do_get(JanetFopts opts, JanetSlot *args) {
 static JanetSlot do_next(JanetFopts opts, JanetSlot *args) {
     return opreduce(opts, args, JOP_NEXT, janet_wrap_nil());
 }
+static JanetSlot do_modulo(JanetFopts opts, JanetSlot *args) {
+    return opreduce(opts, args, JOP_MODULO, janet_wrap_nil());
+}
+static JanetSlot do_remainder(JanetFopts opts, JanetSlot *args) {
+    return opreduce(opts, args, JOP_REMAINDER, janet_wrap_nil());
+}
 static JanetSlot do_put(JanetFopts opts, JanetSlot *args) {
     if (opts.flags & JANET_FOPTS_DROP) {
         janetc_emit_sss(opts.compiler, JOP_PUT, args[0], args[1], args[2], 0);
@@ -287,7 +293,9 @@ static const JanetFunOptimizer optimizers[] = {
     {NULL, do_neq},
     {fixarity2, do_propagate},
     {fixarity2, do_get},
-    {fixarity2, do_next}
+    {fixarity2, do_next},
+    {fixarity2, do_modulo},
+    {fixarity2, do_remainder},
 };
 
 const JanetFunOptimizer *janetc_funopt(uint32_t flags) {

src/core/compile.h

@@ -58,6 +58,8 @@
 #define JANET_FUN_PROP 26
 #define JANET_FUN_GET 27
 #define JANET_FUN_NEXT 28
+#define JANET_FUN_MODULO 29
+#define JANET_FUN_REMAINDER 30
 
 /* Compiler typedefs */
 typedef struct JanetCompiler JanetCompiler;

src/core/corelib.c

@@ -931,6 +931,14 @@ static const uint32_t next_asm[] = {
     JOP_NEXT | (1 << 24),
     JOP_RETURN
 };
+static const uint32_t modulo_asm[] = {
+    JOP_MODULO | (1 << 24),
+    JOP_RETURN
+};
+static const uint32_t remainder_asm[] = {
+    JOP_REMAINDER | (1 << 24),
+    JOP_RETURN
+};
 #endif /* ifdef JANET_BOOTSTRAP */
 
 /*
@@ -973,6 +981,14 @@ static void janet_load_libs(JanetTable *env) {
 
 JanetTable *janet_core_env(JanetTable *replacements) {
     JanetTable *env = (NULL != replacements) ? replacements : janet_table(0);
+    janet_quick_asm(env, JANET_FUN_MODULO,
+                    "mod", 2, 2, 2, 2, modulo_asm, sizeof(modulo_asm),
+                    JDOC("(mod dividend divisor)\n\n"
+                         "Returns the modulo of dividend / divisor."));
+    janet_quick_asm(env, JANET_FUN_REMAINDER,
+                    "%", 2, 2, 2, 2, remainder_asm, sizeof(remainder_asm),
+                    JDOC("(% dividend divisor)\n\n"
+                         "Returns the remainder of dividend / divisor."));
     janet_quick_asm(env, JANET_FUN_NEXT,
                     "next", 2, 2, 2, 2, next_asm, sizeof(next_asm),
                     JDOC("(next ds &opt key)\n\n"

src/core/inttypes.c

@@ -202,7 +202,7 @@ static Janet cfun_it_##type##_##name(int32_t argc, Janet *argv) { \
     janet_arity(argc, 2, -1); \
     T *box = janet_abstract(&it_##type##_type, sizeof(T)); \
     *box = janet_unwrap_##type(argv[0]); \
-    for (int i = 1; i < argc; i++) \
+    for (int32_t i = 1; i < argc; i++) \
         *box oper##= janet_unwrap_##type(argv[i]); \
     return janet_wrap_abstract(box); \
 } \
@@ -221,7 +221,7 @@ static Janet cfun_it_##type##_##name(int32_t argc, Janet *argv) { \
     janet_arity(argc, 2, -1);                       \
     T *box = janet_abstract(&it_##type##_type, sizeof(T)); \
     *box = janet_unwrap_##type(argv[0]); \
-    for (int i = 1; i < argc; i++) { \
+    for (int32_t i = 1; i < argc; i++) { \
       T value = janet_unwrap_##type(argv[i]); \
       if (value == 0) janet_panic("division by zero"); \
       *box oper##= value; \
@@ -245,7 +245,7 @@ static Janet cfun_it_##type##_##name(int32_t argc, Janet *argv) { \
     janet_arity(argc, 2, -1);                       \
     T *box = janet_abstract(&it_##type##_type, sizeof(T)); \
     *box = janet_unwrap_##type(argv[0]); \
-    for (int i = 1; i < argc; i++) { \
+    for (int32_t i = 1; i < argc; i++) { \
       T value = janet_unwrap_##type(argv[i]); \
       if (value == 0) janet_panic("division by zero"); \
       if ((value == -1) && (*box == INT64_MIN)) janet_panic("INT64_MIN divided by -1"); \
@@ -274,14 +274,43 @@ static Janet cfun_it_##type##_##name(int32_t argc, Janet *argv) { \
     return janet_wrap_boolean(v1 oper v2); \
 }
 
+static Janet cfun_it_s64_mod(int32_t argc, Janet *argv) {
+    janet_arity(argc, 2, -1);
+    int64_t *box = janet_abstract(&it_s64_type, sizeof(int64_t));
+    *box = janet_unwrap_s64(argv[0]);
+    for (int32_t i = 1; i < argc; i++) {
+        int64_t value = janet_unwrap_s64(argv[i]);
+        if (value == 0) janet_panic("division by zero");
+        int64_t x = *box % value;
+        if (x < 0) {
+            x = (*box < 0) ? x - *box : x + *box;
+        }
+        *box = x;
+    }
+    return janet_wrap_abstract(box);
+}
+
+static Janet cfun_it_s64_modi(int32_t argc, Janet *argv) {
+    janet_fixarity(argc, 2);
+    int64_t *box = janet_abstract(&it_s64_type, sizeof(int64_t));
+    int64_t op1 = janet_unwrap_s64(argv[0]);
+    int64_t op2 = janet_unwrap_s64(argv[1]);
+    int64_t x = op1 % op2;
+    if (x < 0) {
+        x = (op1 < 0) ? x - op1 : x + op1;
+    }
+    *box = x;
+    return janet_wrap_abstract(box);
+}
+
 OPMETHOD(int64_t, s64, add, +)
 OPMETHOD(int64_t, s64, sub, -)
 OPMETHODINVERT(int64_t, s64, subi, -)
 OPMETHOD(int64_t, s64, mul, *)
 DIVMETHOD_SIGNED(int64_t, s64, div, /)
-DIVMETHOD_SIGNED(int64_t, s64, mod, %)
+DIVMETHOD_SIGNED(int64_t, s64, rem, %)
 DIVMETHODINVERT_SIGNED(int64_t, s64, divi, /)
-DIVMETHODINVERT_SIGNED(int64_t, s64, modi, %)
+DIVMETHODINVERT_SIGNED(int64_t, s64, remi, %)
 OPMETHOD(int64_t, s64, and, &)
 OPMETHOD(int64_t, s64, or, |)
 OPMETHOD(int64_t, s64, xor, ^)
@@ -328,8 +357,10 @@ static JanetMethod it_s64_methods[] = {
     {"r*", cfun_it_s64_mul},
     {"/", cfun_it_s64_div},
     {"r/", cfun_it_s64_divi},
-    {"%", cfun_it_s64_mod},
+    {"mod", cfun_it_s64_mod},
-    {"r%", cfun_it_s64_modi},
+    {"rmod", cfun_it_s64_modi},
+    {"%", cfun_it_s64_rem},
+    {"r%", cfun_it_s64_remi},
     {"<", cfun_it_s64_lt},
     {">", cfun_it_s64_gt},
     {"<=", cfun_it_s64_le},
@@ -357,6 +388,8 @@ static JanetMethod it_u64_methods[] = {
     {"r*", cfun_it_u64_mul},
     {"/", cfun_it_u64_div},
     {"r/", cfun_it_u64_divi},
+    {"mod", cfun_it_u64_mod},
+    {"rmod", cfun_it_u64_modi},
     {"%", cfun_it_u64_mod},
     {"r%", cfun_it_u64_modi},
     {"<", cfun_it_u64_lt},

src/core/math.c

@@ -223,13 +223,6 @@ static Janet janet_srand(int32_t argc, Janet *argv) {
     return janet_wrap_nil();
 }
 
-static Janet janet_remainder(int32_t argc, Janet *argv) {
-    janet_fixarity(argc, 2);
-    double x = janet_getnumber(argv, 0);
-    double y = janet_getnumber(argv, 1);
-    return janet_wrap_number(fmod(x, y));
-}
-
 #define JANET_DEFINE_MATHOP(name, fop)\
 static Janet janet_##name(int32_t argc, Janet *argv) {\
     janet_fixarity(argc, 1); \
@@ -281,11 +274,6 @@ static Janet janet_not(int32_t argc, Janet *argv) {
 }
 
 static const JanetReg math_cfuns[] = {
-    {
-        "%", janet_remainder,
-        JDOC("(% dividend divisor)\n\n"
-             "Returns the remainder of dividend / divisor.")
-    },
     {
         "not", janet_not,
         JDOC("(not x)\n\nReturns the boolean inverse of x.")

src/core/vm.c

@@ -305,6 +305,8 @@ static JanetSignal run_vm(JanetFiber *fiber, Janet in) {
         &&label_JOP_MULTIPLY,
         &&label_JOP_DIVIDE_IMMEDIATE,
         &&label_JOP_DIVIDE,
+        &&label_JOP_MODULO,
+        &&label_JOP_REMAINDER,
         &&label_JOP_BAND,
         &&label_JOP_BOR,
         &&label_JOP_BXOR,
@@ -545,8 +547,6 @@ static JanetSignal run_vm(JanetFiber *fiber, Janet in) {
         &&label_unknown_op,
         &&label_unknown_op,
         &&label_unknown_op,
-        &&label_unknown_op,
-        &&label_unknown_op,
         &&label_unknown_op
     };
 #endif
@@ -642,6 +642,39 @@ static JanetSignal run_vm(JanetFiber *fiber, Janet in) {
     VM_OP(JOP_DIVIDE)
     vm_binop( /);
 
+    VM_OP(JOP_MODULO)
+    {
+        Janet op1 = stack[B];
+        Janet op2 = stack[C];
+        if (janet_checktype(op1, JANET_NUMBER) && janet_checktype(op2, JANET_NUMBER)) {
+            double x1 = janet_unwrap_number(op1);
+            double x2 = janet_unwrap_number(op2);
+            double intres = x2 * floor(x1 / x2);
+            stack[A] = janet_wrap_number(x1 - intres);
+            vm_pcnext();
+        } else {
+            vm_commit();
+            stack[A] = janet_binop_call("mod", "rmod", op1, op2);
+            vm_checkgc_pcnext();
+        }
+    }
+
+    VM_OP(JOP_REMAINDER)
+    {
+        Janet op1 = stack[B];
+        Janet op2 = stack[C];
+        if (janet_checktype(op1, JANET_NUMBER) && janet_checktype(op2, JANET_NUMBER)) {
+            double x1 = janet_unwrap_number(op1);
+            double x2 = janet_unwrap_number(op2);
+            stack[A] = janet_wrap_number(fmod(x1, x2));
+            vm_pcnext();
+        } else {
+            vm_commit();
+            stack[A] = janet_binop_call("%", "r%", op1, op2);
+            vm_checkgc_pcnext();
+        }
+    }
+
     VM_OP(JOP_BAND)
     vm_bitop(&);
 

src/include/janet.h

@@ -1024,6 +1024,8 @@ enum JanetOpCode {
     JOP_MULTIPLY,
     JOP_DIVIDE_IMMEDIATE,
     JOP_DIVIDE,
+    JOP_MODULO,
+    JOP_REMAINDER,
     JOP_BAND,
     JOP_BOR,
     JOP_BXOR,