tisc

commit 6f1aff702d759ee876ac0d7b2a7b65a1bd4cb93b
parent 98ae81c0dc0fbf77f21282c1f439b51888b793bb
Author: Paul Longtine <paul@nanner.co>
Date:   Fri Dec 19 18:27:19 2014

add the thing

Diffstat:
 tisc.c | 226 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 226 insertions(+), 0 deletions(-)
diff --git a/tisc.c b/tisc.c
@@ -0,0 +1,226 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#define MAXSYMBOLS   1000
+#define MAXSYMBOLLEN 100
+#define MAXLINELEN   100
+#define MAX_INSTYPES 4
+
+/*
+ OP CODE SPEC
+  4 bit integers cut in half,
+  LSB is postfix, MSB is prefix (or C)
+
+ C B A OP when OP < 3 otherwise:
+ OPB A OP
+*/
+
+#define ADD  0
+#define NAND 1
+#define OR   2
+#define CIN  2
+#define LLI  3
+#define LUI  7
+#define EXT  11 // extended instructions
+#define CMP  15
+
+char symbols[MAXSYMBOLS][MAXSYMBOLLEN];
+int  addresses[MAXSYMBOLS];
+int  validSymbols = 0;
+
+char *formats[MAX_INSTYPES][8] =
+{
+	// 0 arg instructions
+	{
+		"push",
+		"pop",
+		"pcr",
+		NULL
+	},
+	// 1 arg instructions
+	{
+		"lli",
+		"lui",
+		"jmp",
+		"lb",
+		"sb",
+		"sp",
+		".fill",
+		NULL
+	},
+	// 2 arg instructions
+	{
+		"cmp",
+		NULL
+	},
+	// 3 arg instructions
+	{
+		"add",
+		"nand",
+		"or",
+		"cin",
+		NULL
+	}
+};
+
+/* char *parse -> parses file and sets label, opcode, and args
+   accordingly */
+char *parse(FILE *file, char *line, char **label, char **opcode,
+            char **arg0, char **arg1, char **arg2)
+{
+	char *str, *first;
+	str = fgets(line, MAXLINELEN, file);
+	if (str != NULL)
+	{
+		first = strtok(line, " \t\n");
+		if (first == NULL || first[0] == '#')
+		{
+			return parse(file, line, label, opcode, arg0, arg1, arg2);
+		} else if (first[strlen(first) - 1] == ':')
+		{
+			*label = first;
+			*opcode = strtok(NULL, " \t\n");
+			first[strlen(first) - 1] = '\0';
+		} else
+		{
+			*label = NULL;
+			*opcode = first;
+		}
+		*arg0 = strtok(NULL, " \t\n");
+		*arg1 = strtok(NULL, " \t\n");
+		*arg2 = strtok(NULL, " \t\n");
+	}
+	
+	return(str);
+}
+
+int labelext(const char *label)
+{
+	int i, status = 0;
+
+	for (i = 0; i < validSymbols; i++)
+		if (strcmp(symbols[i], label) == 0) status = 1;
+
+	return status;
+}
+
+int validins(int op, int format, const char *opcode, char *arg[])
+{
+	int status = 0;
+	if (strcmp(formats[format][op], opcode) == 0)
+	{
+		status = 1;
+		if (!(format == 0 && arg[0] == NULL && arg[1] == NULL && arg[2] == NULL ||
+		      format == 1 && arg[0] != NULL && arg[1] == NULL && arg[2] == NULL ||
+		      format == 2 && arg[0] != NULL && arg[1] != NULL && arg[2] == NULL ||
+		      format == 3 && arg[0] != NULL && arg[1] != NULL && arg[2] != NULL ))
+		{
+			status = 2;
+		}
+	}
+
+	return status;
+}
+
+/* int preprocess -> 1st pass over file, links symbols to address
+   and reports syntax errors, fails if returns -1 */
+int preprocess(int address, char *label, char *opcode,
+               char *arg0, char *arg1, char *arg2)
+{
+	int i,op;
+	int status = 0;
+
+	// arguement check
+	for (i = 0; i < MAX_INSTYPES; i++)
+	{
+		for (op = 0; formats[i][op] != NULL; op++)
+		{
+			char *args[3] = {arg0, arg2, arg2};
+			if (status == 0) status = validins(op, i, opcode, args);
+		}
+	}
+	switch (status)
+	{
+		case 0:
+			printf("Error:%i: instruction '%s' does not exist\n",address, opcode);
+			status = 1;
+		case 2:
+			printf("Error:%i: not enough arguements for '%s'\n",address, opcode);
+			status = 1;
+	}
+
+	//duplicate label check
+	if (label != NULL)
+	{
+		if (labelext(label) == 1)
+		{
+			printf("Error:%i: label exists '%s'\n",address, label);
+		} else
+		{
+			strcpy(symbols[validSymbols], label);
+			addresses[validSymbols] = address;
+			validSymbols++;
+		}
+	}
+
+	return status;
+}
+/* int process -> 2nd pass over file, instrutions are turned into
+   machine code with symbols filled in as adresses, 
+   fails if returns -1 */
+int process(int address, FILE *outfile, char *label, char *opcode,
+            char *arg0, char *arg1, char *arg2)
+{
+	return 0;
+}
+
+int main(int argc, char *argv[])
+{
+	if (argc != 3)
+	{
+		fprintf(stderr, "error useage: %s <assembly-code-file> <machine-code-file> \n", argv[0]);
+		exit(1);
+	}
+
+	char *input,  *output;
+	FILE *inputf, *outputf;
+	char *labels, *opcodes, *args0, *args1, *args2;
+	char lines[MAXLINELEN+1];
+	
+	int address = 0;
+
+	input = argv[1];
+	output = argv[2];
+
+	inputf = fopen(input, "r");
+	if (inputf == NULL)
+	{
+		fprintf(stderr, "Error opening file '%s'", input);
+		exit(1);
+	}
+	outputf = fopen(output, "w");
+	if (outputf == NULL)
+	{
+		fprintf(stderr, "Error opening file '%s'", output);
+		exit(1);
+	}
+
+	while (parse(inputf, lines, &labels, &opcodes, &args0, &args1, &args2) != NULL)
+	{
+		if (preprocess(address, labels, opcodes, args0, args1, args2) == 0) exit(1);
+		address++;
+	}
+
+	rewind(inputf);
+	address = 0;
+
+	while (parse(inputf, lines, &labels, &opcodes, &args0, &args1, &args2) != NULL)
+	{
+		if (process(address, outputf, labels, opcodes, args0, args1, args2) == 0) exit(1);
+		address++;
+	}
+	fclose(inputf);
+	fclose(outputf);
+	return 1;
+}