add: sqrt, neg instructions, fix: pushing register with value 0

Makefile

@@ -7,7 +7,7 @@ OBJ = $(SRC:.c=.o)
 NAME = pasm
 CC = gcc
 CFLAGS = -Wall -Wextra -Wpedantic -Iinclude -s -Os -fno-ident -fno-asynchronous-unwind-tables
-CLIBS =
+CLIBS = -lm
 
 all:	$(NAME)
 

docs/documentation.md

@@ -71,6 +71,8 @@ The syntax is very close to x86 Intel Assembly. Here is a list of the operands a
 | **sub** a1, a2   | Substract a2 from a1  | no            |
 | **mul** a1, a2   | Multiplies a2 with a1 | no            |
 | **div** a1, a2   | Divides a2 from a1    | no            |
+| **sqrt** a1      | computes sqrt(a1)     | no            |
+| **neg** a1       | a1 = -a1              | no            |
 | **and** a1, a2   | Performs a bitwise AND between a1 and a2. Stores the result in eax. | yes |
 | **xor** a1, a2   | Performs a XOR opration between a1 and a2. Stores the result in eax.| yes |
 | **mov** a1, a2   | Moves the value stored in a2 in a1 | no |

src/instructions.c

@@ -1,6 +1,7 @@
 #include "instructions.h"
 #include "interpreter_states.h"
 #include "api.h"
+#include <math.h>
 #include <string.h>
 #include <stdlib.h>
 
@@ -25,7 +26,7 @@ bool check_args(s_arguments *args, int num_in_first, int num_args) {
 	return false;
     }
 
-    if ((!is_num(args->arg2) && !is_reg(args->arg2))) {
+    if ((!is_num(args->arg2) && !is_reg(args->arg2)) && num_args == 2) {
 	state->last_check_args_code = ARG2_WRONG;
 	return false;
     }
@@ -189,6 +190,23 @@ void add() {
     *get_reg(state->args->arg1) += get_value(state->args->arg2);
 }
 
+
+void _sqrt() {
+    if (!check_args(state->args, 0, 1)) {
+	return;
+    }
+
+    *get_reg(state->args->arg1) = sqrt(get_value(state->args->arg1));
+}
+
+void neg() {
+    if (!check_args(state->args, 0, 1)) {
+	return;
+    }
+
+    *get_reg(state->args->arg1) = -get_value(state->args->arg1);
+}
+
 void mul() {
     if (!check_args(state->args, 0, 2)) {
 	return;
@@ -230,7 +248,7 @@ void push() {
     }
     
     int value = get_value(state->args->arg1);
-    if (value == 0) {
+    if (value == 0 && !is_reg(state->args->arg1)) {
 	if (state->args->arg1[0] == '\\') {
 	    switch (state->args->arg1[1]) {
 		case 'n':

src/instructions.h

@@ -11,6 +11,7 @@ typedef struct command_s {
 bool is_reg(char* arg);
 bool check_args(s_arguments *args, int num_in_first, int num_args);
 int* get_reg(char* arg);
+int get_value(char* arg);
 
 void add();
 void sub();
@@ -29,6 +30,8 @@ void ret();
 void pop();
 void push();
 void call();
+void neg();
+void _sqrt();
 void _and();
 void _xor();
 void end();
@@ -51,6 +54,8 @@ static const command_t command_map[] = {
     {.command = "pop", .fptr = pop},
     {.command = "push", .fptr = push},
     {.command = "call", .fptr = call},
+    {.command = "sqrt", .fptr = _sqrt},
+    {.command = "neg", .fptr = neg},
     {.command = "and", .fptr = _and},
     {.command = "xor", .fptr = _xor},
     {.command = "end", .fptr = end},