Updated tests to use printsignednumber subroutine from debug.pvvs instead of stdio...

[vvhitespace] / vv_interpreter.c

diff --git a/vv_interpreter.c b/vv_interpreter.c
index ca2f772..b548a50 100644 (file)
--- a/vv_interpreter.c
+++ b/vv_interpreter.c
@@ -15,9 +15,9 @@
 
 #define VERSION 1
 
 
 #define VERSION 1
 

-#define STACKSIZE 1024
-#define HEAPSIZE  1024
-#define RETURNSTACKSIZE 1024
+#define HEAPSIZE        1024    /* Size of heap in words        */
+#define DATASTACKSIZE   1024    /* Size of stack in words       */
+#define RETURNSTACKSIZE 1024    /* Max subroutine call depth    */

 
 void
 print_usage(char ** argv)
 
 void
 print_usage(char ** argv)


@@ -83,19 +83,19 @@ ws_die(size_t * pc, char * msg)
 }
 
 void
 }
 
 void

-stack_push(int32_t ** sp, int32_t word)
+stack_push(int64_t ** sp, int64_t word)

 {
     *((*sp)++) = word;
 }
 
 {
     *((*sp)++) = word;
 }
 

-int32_t
-stack_pop(int32_t ** sp)
+int64_t
+stack_pop(int64_t ** sp)

 {
     return *(--(*sp));
 }
 
 {
     return *(--(*sp));
 }
 

-int32_t
-stack_peek(int32_t ** sp, size_t offset)
+int64_t
+stack_peek(int64_t ** sp, size_t offset)

 /* offset=0 peeks TOS, offset=1 peeks NOS, etc. */
 {
     return *((*sp)-offset-1);
 /* offset=0 peeks TOS, offset=1 peeks NOS, etc. */
 {
     return *((*sp)-offset-1);


@@ -118,35 +118,42 @@ parse_label(uint8_t * code, size_t * pc)
     uint8_t c;
     while ((c = code[(*pc)++]) != '\n') {
         label = label << 1;
     uint8_t c;
     while ((c = code[(*pc)++]) != '\n') {
         label = label << 1;

-        if (c == ' ') label++;
+        if (c == '\t') label++;
+    }
+    return label;
+}
+
+uint16_t
+check_label(size_t * labels, uint16_t label, size_t * pc)
+{
+    if (!labels[label]) {
+        fprintf(stderr, "Trying to process label 0x%X.\n", label);
+        ws_die(pc, "uninitialized label (forgot an include?)");

     }
     }

-    // TODO: Where should I handle attempts to access an unitialized label?
-    //       For now, leave it undefined in a nasal demon sense.

     return label;
 }
 
 void
     return label;
 }
 
 void

-populate_labels(uint32_t * labels, uint8_t * code, size_t code_size)
+populate_labels(size_t * labels, uint8_t * code, size_t code_size)

 {
     size_t cp = 0;
     while (cp <= code_size) {
 {
     size_t cp = 0;
     while (cp <= code_size) {

-        if (code[cp] == '\v') {
+        if (code[cp++] == '\v') {

             uint16_t temp_label = parse_label(code, &cp);
             labels[temp_label] = cp;
         }
             uint16_t temp_label = parse_label(code, &cp);
             labels[temp_label] = cp;
         }

-        cp++;

     }
 }
 
 void
     }
 }
 
 void

-process_imp_stack(uint8_t * code, size_t * pc, int32_t ** sp)
+process_imp_stack(uint8_t * code, size_t * pc, int64_t ** sp)

 {
     switch (next_code_byte(code,pc)) {
         case ' ':
             /* Push number onto TOS. */
             {
                 /* First, pick off the sign */
 {
     switch (next_code_byte(code,pc)) {
         case ' ':
             /* Push number onto TOS. */
             {
                 /* First, pick off the sign */

-                int32_t sign = 0;
+                int64_t sign = 0;

                 switch (next_code_byte(code,pc)) {
                     case ' ' :  sign = 1;                       break;
                     case '\t':  sign = -1;                      break;
                 switch (next_code_byte(code,pc)) {
                     case ' ' :  sign = 1;                       break;
                     case '\t':  sign = -1;                      break;


@@ -155,13 +162,26 @@ process_imp_stack(uint8_t * code, size_t * pc, int32_t ** sp)
 
                 /* Now, construct the number and push to TOS. */
                 /* I'm assuming the numbers are read MSb first. */
 
                 /* Now, construct the number and push to TOS. */
                 /* I'm assuming the numbers are read MSb first. */

-                int32_t temp, number = 0;
+                uint64_t number = 0; /* Unsigned to accomodate magnitude of most negative number. */
+                uint8_t temp;

                 while ((temp = next_code_byte(code,pc)) != '\n') {
                     if (temp == '\v') ws_die(pc, "non-binary digit in number");
                     number <<= 1;
                     if (temp == '\t') number++;
                 }
                 while ((temp = next_code_byte(code,pc)) != '\n') {
                     if (temp == '\v') ws_die(pc, "non-binary digit in number");
                     number <<= 1;
                     if (temp == '\t') number++;
                 }

-                stack_push(sp, number*sign);
+                /* Without temporarily casting to something >64-bit, the most negative */
+                /* number will overflow when performing 'number*sign'. Instead, we     */
+                /* pick off the most negative number as a special case.                */
+                if (number == (1ULL << 63) && sign == -1) {
+                    /* C parses negative integer literals first as signed positive */
+                    /* integer literals, then applying a unary negation operator.  */
+                    /* Thus, the most negative value is unreachable directly.      */
+                    int64_t number_temp = -9223372036854775807LL; /* First store -((2^63)-1)  */
+                    number_temp--;                                /* Now turn it into -(2^63) */
+                    stack_push(sp, number_temp);
+                } else {
+                    stack_push(sp, number*sign);
+                }

             }
             break;
         case '\n':
             }
             break;
         case '\n':


@@ -175,8 +195,8 @@ process_imp_stack(uint8_t * code, size_t * pc, int32_t ** sp)
                         /* Swap TOS and NOS. */
                     case '\t':
                         {
                         /* Swap TOS and NOS. */
                     case '\t':
                         {

-                            int32_t t1 = stack_pop(sp);
-                            int32_t t2 = stack_pop(sp);
+                            int64_t t1 = stack_pop(sp);
+                            int64_t t2 = stack_pop(sp);

                             stack_push(sp, t1);
                             stack_push(sp, t2);
                         }
                             stack_push(sp, t1);
                             stack_push(sp, t2);
                         }


@@ -196,9 +216,9 @@ process_imp_stack(uint8_t * code, size_t * pc, int32_t ** sp)
 }
 
 void
 }
 
 void

-process_imp_arithmetic(uint8_t * code, size_t * pc, int32_t ** sp)
+process_imp_arithmetic(uint8_t * code, size_t * pc, int64_t ** sp)

 {
 {

-    int32_t temp;
+    int64_t temp;

     switch (next_code_byte(code,pc)) {
         case ' ':
             {
     switch (next_code_byte(code,pc)) {
         case ' ':
             {


@@ -233,7 +253,7 @@ process_imp_arithmetic(uint8_t * code, size_t * pc, int32_t ** sp)
                     case '\t':
                         /* Modulo */
                         temp = stack_pop(sp);
                     case '\t':
                         /* Modulo */
                         temp = stack_pop(sp);

-                        stack_push(sp, stack_pop(sp)%temp);
+                        stack_push(sp, llabs(stack_pop(sp) % llabs(temp)));

                         break;
                     default: ws_die(pc, "malformed arithmetic IMP"); break;
                 }
                         break;
                     default: ws_die(pc, "malformed arithmetic IMP"); break;
                 }


@@ -244,9 +264,10 @@ process_imp_arithmetic(uint8_t * code, size_t * pc, int32_t ** sp)
 }
 
 void
 }
 
 void

-process_imp_flowcontrol(uint8_t * code, size_t * pc, int32_t ** sp, uint32_t * labels,
-                        uint32_t ** rsp)
+process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * labels,
+                        size_t ** rsp)

 {
 {

+    size_t temp_pc;

     switch (next_code_byte(code,pc)) {
         case '\n':
             /* Technically another LF is required but we ignore it. */
     switch (next_code_byte(code,pc)) {
         case '\n':
             /* Technically another LF is required but we ignore it. */


@@ -265,15 +286,13 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int32_t ** sp, uint32_t * l
                         break;
                     case '\t':
                         /* Call a subroutine. */
                         break;
                     case '\t':
                         /* Call a subroutine. */

-                        {
-                            size_t temp_pc = labels[parse_label(code, pc)];
-                            *((*rsp)++) = *pc;
-                            *pc = temp_pc;
-                        }
+                        temp_pc = labels[check_label(labels, parse_label(code, pc), pc)];
+                        *((*rsp)++) = *pc;
+                        *pc = temp_pc;

                         break;
                     case '\n':
                         /* Jump unconditionally to a label. */
                         break;
                     case '\n':
                         /* Jump unconditionally to a label. */

-                        *pc = labels[parse_label(code, pc)];
+                        *pc = labels[check_label(labels, parse_label(code, pc), pc)];

                         break;
                     default:
                         ws_die(pc, "malformed flow control IMP");
                         break;
                     default:
                         ws_die(pc, "malformed flow control IMP");


@@ -286,13 +305,13 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int32_t ** sp, uint32_t * l
                 switch (next_code_byte(code,pc)) {
                     case ' ':
                         /* Jump to a label if TOS == 0 */
                 switch (next_code_byte(code,pc)) {
                     case ' ':
                         /* Jump to a label if TOS == 0 */

-                        /* TODO: Does WS pop or peek the TOS? */
-                        if (stack_peek(sp,0) == 0) *pc = labels[parse_label(code, pc)];
+                        temp_pc = labels[check_label(labels, parse_label(code, pc), pc)];
+                        if (stack_pop(sp) == 0) *pc = temp_pc;

                         break;
                     case '\t':
                         /* Jump to a label if TOS < 0. */
                         break;
                     case '\t':
                         /* Jump to a label if TOS < 0. */

-                        /* TODO: Does WS pop or peek the TOS? */
-                        if (stack_peek(sp,0) < 0) *pc = labels[parse_label(code, pc)];
+                        temp_pc = labels[check_label(labels, parse_label(code, pc), pc)];
+                        if (stack_pop(sp) < 0) *pc = temp_pc;

                         break;
                     case '\n':
                         /* Return from subroutine. */
                         break;
                     case '\n':
                         /* Return from subroutine. */


@@ -311,14 +330,14 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int32_t ** sp, uint32_t * l
 }
 
 void
 }
 
 void

-process_imp_heap(uint8_t * code, size_t * pc, int32_t ** sp, int32_t ** hp)
+process_imp_heap(uint8_t * code, size_t * pc, int64_t ** sp, int64_t ** hp)

 {
     switch (next_code_byte(code,pc)) {
         case ' ' :
             /* Store to heap */
             {
 {
     switch (next_code_byte(code,pc)) {
         case ' ' :
             /* Store to heap */
             {

-                int32_t value = stack_pop(sp);
-                int32_t addr = stack_pop(sp);
+                int64_t value = stack_pop(sp);
+                int64_t addr  = stack_pop(sp);

                 *(*hp + addr) = value;
             }
             break;
                 *(*hp + addr) = value;
             }
             break;


@@ -333,15 +352,15 @@ process_imp_heap(uint8_t * code, size_t * pc, int32_t ** sp, int32_t ** hp)
 }
 
 void
 }
 
 void

-process_imp_io(uint8_t * code, size_t * pc, int32_t ** sp, int32_t ** hp)
+process_imp_io(uint8_t * code, size_t * pc, int64_t ** sp, int64_t ** hp)

 {
     switch (next_code_byte(code,pc)) {
         case ' ':
             /* Output */
             {
                 switch (next_code_byte(code,pc)) {
 {
     switch (next_code_byte(code,pc)) {
         case ' ':
             /* Output */
             {
                 switch (next_code_byte(code,pc)) {

-                    case ' ' : /* Output char from TOS  */ printf("%c", stack_pop(sp));     break;
-                    case '\t': /* Output digit from TOS */ printf("%c", stack_pop(sp)+'0'); break;
+                    case ' ' : /* Output char from TOS  */ printf("%c", (uint8_t) stack_pop(sp));     break;
+                    case '\t': /* Output digit from TOS */ printf("%c", (uint8_t) stack_pop(sp)+'0'); break;

                     default  : ws_die(pc, "malformed output IMP");                          break;
                 }
                 fflush(stdout);
                     default  : ws_die(pc, "malformed output IMP");                          break;
                 }
                 fflush(stdout);


@@ -393,7 +412,7 @@ main(int argc, char ** argv)
     }
 
     /*
     }
 
     /*

-     * Read just the VVhitespace source code into memory.
+     * Read just the VVhitespace source code into memory, stripping comment characters.

      * We will use the array indices as addresses for the virtual PC when jumping to labels.
      */
     size_t ws_code_size = 0;
      * We will use the array indices as addresses for the virtual PC when jumping to labels.
      */
     size_t ws_code_size = 0;


@@ -415,17 +434,16 @@ main(int argc, char ** argv)
 
     /*
      * Setup a stack and heap.
 
     /*
      * Setup a stack and heap.

-     * Assume a 32-bit word size.

      */
      */

-    // TODO: Make everything 64-bit.
-    int32_t * hp = malloc(HEAPSIZE*4);
-    int32_t * sp = malloc(STACKSIZE*4);
+    int64_t * hp = malloc(HEAPSIZE*sizeof(int64_t));
+    int64_t * sp = malloc(DATASTACKSIZE*sizeof(int64_t));

 
     /* 
      * Setup the return stack and the label array.
      */
 
     /* 
      * Setup the return stack and the label array.
      */

-    uint32_t * rsp = malloc(RETURNSTACKSIZE*4);
-    uint32_t labels[65536] = {0};
+    size_t * rsp = malloc(RETURNSTACKSIZE*sizeof(size_t));
+    size_t labels[65536] = {0}; /* 65536 = 2^16 => Holds all possible labels.               */
+                                /* Default value of zero indicates an uninitialized label.  */

     populate_labels(labels, ws_code_space, ws_code_size);
 
     /*
     populate_labels(labels, ws_code_space, ws_code_size);
 
     /*


@@ -440,8 +458,6 @@ main(int argc, char ** argv)
             exit(EXIT_FAILURE);
             unset_terminal_mode();
         }
             exit(EXIT_FAILURE);
             unset_terminal_mode();
         }

-// TODO: Have the SIGTERM signal handler and normal term point return the value
-// on TOS so I can do rudimentary automated tests.

 
         /* Decode the IMPs */
         switch (ws_code_space[pc++]) {
 
         /* Decode the IMPs */
         switch (ws_code_space[pc++]) {


@@ -472,13 +488,7 @@ main(int argc, char ** argv)
                     }
                 }
                 break;
                     }
                 }
                 break;

-            default: ws_die(&pc, "unexpected VTab"); break;
+            default: ws_die(&pc, "unexpected byte"); break;

         }
     }
         }
     }

-
-    printf("\n");
-    printf("Program executed.\n");
-
-    exit(EXIT_SUCCESS);
-    unset_terminal_mode();

 }
 }