Improving and enhancing integer literal scanning in selfie

selfie.c

@@ -232,6 +232,7 @@ uint64_t SIZEOFUINT = 8; // size of target-dependent unsigned integer in byt
 uint64_t SIZEOFUINTSTAR = 8; // size of target-dependent pointer to unsigned integer in bytes
 
 uint64_t UINT_MAX; // maximum numerical value of target-dependent unsigned integer
+uint64_t INT_MIN; // minimum numerical value of target-dependent signed integer
 
 uint64_t WORDSIZE = 8; // target-dependent word size in bytes
 uint64_t WORDSIZEINBITS = 64; // WORDSIZE * 8
@@ -331,6 +332,7 @@ void init_library() {
  SIZEOFUINT = sizeof(uint64_t);
  SIZEOFUINTSTAR = sizeof(uint64_t*);
  UINT_MAX = UINT64_MAX;
+ INT_MIN = INT64_MIN;
  WORDSIZE = sizeof(uint64_t);
  WORDSIZEINBITS = WORDSIZE * 8;
 
@@ -2541,9 +2543,8 @@ void init_target() {
  if (IS64BITSYSTEM) {
  SIZEOFUINT = sizeof(uint64_t);
  SIZEOFUINTSTAR = sizeof(uint64_t*);
-
- UINT_MAX = UINT64_MAX;
-
+ UINT_MAX = UINT64_MAX;
+ INT_MIN = INT64_MIN;
  WORDSIZE = sizeof(uint64_t);
  WORDSIZEINBITS = WORDSIZE * 8;
 
@@ -2564,17 +2565,15 @@ void init_target() {
  if (IS64BITSYSTEM) {
  SIZEOFUINT = SINGLEWORDSIZE;
  SIZEOFUINTSTAR = SINGLEWORDSIZE;
-
- UINT_MAX = two_to_the_power_of(SINGLEWORDSIZEINBITS) - 1;
-
- WORDSIZE = SINGLEWORDSIZE;
+ UINT_MAX = two_to_the_power_of(SINGLEWORDSIZEINBITS) - 1;
+ INT_MIN = two_to_the_power_of(SINGLEWORDSIZEINBITS - 1);
+ WORDSIZE = SINGLEWORDSIZE;
  } else {
  SIZEOFUINT = sizeof(uint64_t);
  SIZEOFUINTSTAR = sizeof(uint64_t*);
-
- UINT_MAX = UINT64_MAX;
-
- WORDSIZE = sizeof(uint64_t);
+ UINT_MAX = UINT64_MAX;
+ INT_MIN = INT64_MIN;
+ WORDSIZE = sizeof(uint64_t);
  }
 
  WORDSIZEINBITS = WORDSIZE * 8;
@@ -2874,6 +2873,7 @@ uint64_t atoi(char* s) {
  uint64_t i;
  uint64_t n;
  uint64_t c;
+ uint64_t sign;
 
  // the conversion of the ASCII string in s to its
  // numerical value n begins with the leftmost digit in s
@@ -2886,6 +2886,16 @@ uint64_t atoi(char* s) {
  // bit shifting since memory access can only be done at word granularity
  c = load_character(s, i);
 
+ // only used by console argument scanner
+ if (c == '-') {
+ sign = 1;
+
+ i = i + 1;
+
+ c = load_character(s, i);
+ } else
+ sign = 0;
+
  // loop until s is terminated
  while (c != 0) {
  // the numerical value of ASCII-encoded decimal digits
@@ -2901,19 +2911,19 @@ uint64_t atoi(char* s) {
  // assert: s contains a decimal number
 
  // use base 10 but detect wrap around
- if (n < UINT_MAX / 10)
+ if (n < UINT64_MAX / 10)
  n = n * 10 + c;
- else if (n == UINT_MAX / 10)
- if (c <= UINT_MAX % 10)
+ else if (n == UINT64_MAX / 10)
+ if (c <= UINT64_MAX % 10)
  n = n * 10 + c;
  else {
- // s contains a decimal number larger than UINT_MAX
+ // s contains a decimal number larger than UINT64_MAX
  printf("%s: cannot convert out-of-bound number %s\n", selfie_name, s);
 
  exit(EXITCODE_SCANNERERROR);
  }
  else {
- // s contains a decimal number larger than UINT_MAX
+ // s contains a decimal number larger than UINT64_MAX
  printf("%s: cannot convert out-of-bound number %s\n", selfie_name, s);
 
  exit(EXITCODE_SCANNERERROR);
@@ -2927,7 +2937,17 @@ uint64_t atoi(char* s) {
  c = load_character(s, i);
  }
 
- return n;
+ if (sign)
+ if (n <= INT64_MIN)
+ return -n;
+ else {
+ // s contains a decimal number smaller than INT64_MIN
+ printf("%s: cannot convert out-of-bound number %s\n", selfie_name, s);
+
+ exit(EXITCODE_SCANNERERROR);
+ }
+ else
+ return n;
 }
 
 char* itoa(uint64_t n, char* s, uint64_t b, uint64_t d, uint64_t a) {
@@ -3748,7 +3768,7 @@ void get_symbol() {
  if (integer_is_signed)
  syntax_error_message("signed integer out of bound");
  else
- syntax_error_message("integer out of bound");
+ syntax_error_message("unsigned integer out of bound");
 
  exit(EXITCODE_SCANNERERROR);
  }
@@ -3764,12 +3784,17 @@ void get_symbol() {
 
  literal = atoi(integer);
 
- if (integer_is_signed)
- if (literal > INT64_MIN) {
- syntax_error_message("signed integer out of bound");
+ if (integer_is_signed) {
+ if (literal > INT_MIN) {
+ syntax_error_message("signed integer out of target bound");
+
+ exit(EXITCODE_SCANNERERROR);
+ }
+ } else if (literal > UINT_MAX) {
+ syntax_error_message("unsigned integer out of target bound");
 
-  exit(EXITCODE_SCANNERERROR);
-  }
+ exit(EXITCODE_SCANNERERROR);
+ }
  }
 
  symbol = SYM_INTEGER;