diff --git a/input.c b/input.c
index 0d45f94..baf835c 100644
--- a/input.c
+++ b/input.c
@@ -1,7 +1,12 @@
 ident_
 i1dent
 i\uffffent
-i\UFFfFaaAadent
+i\UFFfFaaAadent // comment
+
+/*
+multi
+line
+comment */
 
 123
 0707
@@ -72,4 +77,4 @@ L"\uffFF\xff"
 ? : ; ...
 = *= /= %= += -= <<=
 , # ##
-<: :> <% %> %: %:%:
\ No newline at end of file
+<: :> <% %> %: %:%:
diff --git a/main.c b/main.c
index 309852e..383485d 100644
--- a/main.c
+++ b/main.c
@@ -37,6 +37,22 @@ struct token {
     char *end; // one past end
 };
 
+static unsigned long long
+usec_now(void)
+{
+    struct timespec tp = { 0 };
+    clock_gettime(CLOCK_MONOTONIC_RAW, &tp);
+    unsigned long long now = tp.tv_sec * 1000000ULL + tp.tv_nsec / 1000ULL;
+    return(now);
+}
+
+static inline void
+advance(struct str *s, int by)
+{
+    s->text += by;
+    s->size -= by;
+}
+
 static int
 nondigit(struct str s)
 {
@@ -159,23 +175,19 @@ integer_suffix(struct str s)
     int sym = 0;
     
     if ((sym = unsigned_suffix(s))) {
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         
         int ll = long_long_suffix(s);
-        
         if (ll) {
             return(sym + ll);
         }
         
         return(sym + long_suffix(s));
     } else if ((sym = long_long_suffix(s))) {
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         return(sym + unsigned_suffix(s));
     } else if ((sym = long_suffix(s))) {
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         return(sym + unsigned_suffix(s));
     }
     
@@ -206,20 +218,16 @@ octal_escape_sequence(struct str s)
     int start = s.size;
     
     if (s.size && s.text[0] == '\\') {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         if (octal_digit(s)) {
-            s.text++;
-            s.size--;
+            advance(&s, 1);
             
             if (octal_digit(s)) {
-                s.text++;
-                s.size--;
+                advance(&s, 1);
                 
                 if (octal_digit(s)) {
-                    s.text++;
-                    s.size--;
+                    advance(&s, 1);
                 }
             }
             
@@ -237,17 +245,14 @@ hexadecimal_escape_sequence(struct str s)
     
     if (s.size >= 2) {
         if (s.text[0] == '\\' && s.text[1] == 'x') {
-            s.text += 2;
-            s.size -= 2;
+            advance(&s, 2);
             
             if (hexadecimal_digit(s)) {
-                s.text++;
-                s.size--;
+                advance(&s, 1);
                 
                 for (;;) {
                     if (hexadecimal_digit(s)) {
-                        s.text++;
-                        s.size--;
+                        advance(&s, 1);
                     } else {
                         break;
                     }
@@ -266,14 +271,11 @@ hex_quad(struct str s)
 {
     if (s.size >= 4) {
         if (hexadecimal_digit(s)) {
-            s.text++;
-            s.size--;
+            advance(&s, 1);
             if (hexadecimal_digit(s)) {
-                s.text++;
-                s.size--;
+                advance(&s, 1);
                 if (hexadecimal_digit(s)) {
-                    s.text++;
-                    s.size--;
+                    advance(&s, 1);
                     if (hexadecimal_digit(s)) {
                         return(4);
                     }
@@ -293,19 +295,16 @@ universal_character_name(struct str s)
     
     if (s.text[0] == '\\') {
         if (s.text[1] == 'u') {
-            s.text += 2;
-            s.size -= 2;
+            advance(&s, 2);
             int hq = hex_quad(s);
             if (hq) {
                 return(2 + hq);
             }
         } else if (s.text[1] == 'U') {
-            s.text += 2;
-            s.size -= 2;
+            advance(&s, 2);
             int hq1 = hex_quad(s);
             if (hq1) {
-                s.text += hq1;
-                s.size -= hq1;
+                advance(&s, hq1);
                 int hq2 = hex_quad(s);
                 if (hq2) {
                     return(2 + hq1 + hq2);
@@ -336,15 +335,13 @@ identifier(struct str s)
     int in = identifier_nondigit(s);
     
     if (in) {
-        s.text += in;
-        s.size -= in;
+        advance(&s, in);
         
         int sym = 0;
         
         for (;;) {
             if ((sym = identifier_nondigit(s)) || (sym = digit(s))) {
-                s.text += sym;
-                s.size -= sym;
+                advance(&s, sym);
             } else {
                 break;
             }
@@ -362,13 +359,11 @@ decimal_constant(struct str s)
     int start = s.size;
     
     if (nonzero_digit(s)) {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         for (;;) {
             if (digit(s)) {
-                s.text++;
-                s.size--;
+                advance(&s, 1);
             } else {
                 break;
             }
@@ -387,13 +382,11 @@ octal_constant(struct str s)
     
     if (s.size) {
         if (s.text[0] == '0') {
-            s.text++;
-            s.size--;
+            advance(&s, 1);
             
             for (;;) {
                 if (octal_digit(s)) {
-                    s.text++;
-                    s.size--;
+                    advance(&s, 1);
                 } else {
                     break;
                 }
@@ -413,17 +406,14 @@ hexadecimal_constant(struct str s)
     int hp = hexadecimal_prefix(s);
     
     if (hp) {
-        s.text += hp;
-        s.size -= hp;
+        advance(&s, hp);
         
         if (hexadecimal_digit(s)) {
-            s.text++;
-            s.size--;
+            advance(&s, 1);
             
             for (;;) {
                 if (hexadecimal_digit(s)) {
-                    s.text++;
-                    s.size--;
+                    advance(&s, 1);
                 } else {
                     break;
                 }
@@ -442,8 +432,7 @@ integer_constant(struct str s)
     int sym = 0;
     
     if ((sym = hexadecimal_constant(s)) || (sym = octal_constant(s)) || (sym = decimal_constant(s))) {
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         return(sym + integer_suffix(s));
     }
     
@@ -456,13 +445,11 @@ digit_sequence(struct str s)
     int start = s.size;
     
     if (digit(s)) {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         for (;;) {
             if (digit(s)) {
-                s.text++;
-                s.size--;
+                advance(&s, 1);
             } else {
                 break;
             }
@@ -484,13 +471,10 @@ fractional_constant(struct str s)
     
     if (s.size) {
         if (s.text[0] == '.') {
-            s.text++;
-            s.size--;
+            advance(&s, 1);
             
             int ds2 = digit_sequence(s);
-            
-            s.text += ds2;
-            s.size -= ds2;
+            advance(&s, ds2);
             
             if (ds1 > 0 || ds2 > 0) {
                 return(ds1 + ds2 + 1);
@@ -508,17 +492,14 @@ exponent_part(struct str s)
     
     if (s.size) {
         if (s.text[0] == 'e' || s.text[0] == 'E') {
-            s.text++;
-            s.size--;
+            advance(&s, 1);
             
             int sgn = sign(s);
-            s.text += sgn;
-            s.size -= sgn;
+            advance(&s, sgn);
             
             int ds = digit_sequence(s);
             if (ds) {
-                s.text += ds;
-                s.size -= ds;
+                advance(&s, ds);
                 return(start - s.size);
             }
         }
@@ -532,23 +513,19 @@ decimal_floating_constant(struct str s)
 {
     int sym = 0;
     if ((sym = fractional_constant(s))) {
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         
         int ep = exponent_part(s);
-        s.text += ep;
-        s.size -= ep;
+        advance(&s, ep);
         
         return(sym + ep + floating_suffix(s));
     } else if ((sym = digit_sequence(s))) {
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         
         int ep = 0;
         
         if ((ep = exponent_part(s))) {
-            s.text += ep;
-            s.size -= ep;
+            advance(&s, ep);
             return(sym + ep + floating_suffix(s));
         }
     }
@@ -562,13 +539,11 @@ hexadecimal_digit_sequence(struct str s)
     int start = s.size;
     
     if (hexadecimal_digit(s)) {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         for (;;) {
             if (hexadecimal_digit(s)) {
-                s.text++;
-                s.size--;
+                advance(&s, 1);
             } else {
                 break;
             }
@@ -585,12 +560,10 @@ hexadecimal_fractional_constant(struct str s)
 {
     int hds1 = hexadecimal_digit_sequence(s);
     
-    s.text += hds1;
-    s.size -= hds1;
+    advance(&s, hds1);
     
     if (s.size && s.text[0] == '.') {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         int hds2 = hexadecimal_digit_sequence(s);
         
@@ -608,16 +581,14 @@ binary_exponent_part(struct str s)
     int start = s.size;
     
     if (s.size && (s.text[0] == 'p' || s.text[0] == 'P')) {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         int sgn = sign(s);
-        s.text += sgn;
-        s.size -= sgn;
+        advance(&s, sgn);
         
         int ds = digit_sequence(s);
         if (ds) {
-            s.size -= ds;
+            advance(&s, ds);
             return(start - s.size);
         }
     }
@@ -632,28 +603,23 @@ hexadecimal_floating_constant(struct str s)
     int start = s.size;
     
     if ((hp = hexadecimal_prefix(s))) {
-        s.text += hp;
-        s.size -= hp;
+        advance(&s, hp);
         
         int hfc = 0;
         int hds = 0;
         
         if ((hfc = hexadecimal_fractional_constant(s))) {
-            s.text += hfc;
-            s.size -= hfc;
+            advance(&s, hfc);
             int bep = binary_exponent_part(s);
             if (bep) {
-                s.text += bep;
-                s.size -= bep;
+                advance(&s, bep);
                 return(start - s.size + floating_suffix(s));
             }
         } else if ((hds = hexadecimal_digit_sequence(s))) {
-            s.text += hds;
-            s.size -= hds;
+            advance(&s, hds);
             int bep = binary_exponent_part(s);
             if (bep) {
-                s.text += bep;
-                s.size -= bep;
+                advance(&s, bep);
                 return(start - s.size + floating_suffix(s));
             }
         }
@@ -742,13 +708,11 @@ c_char_sequence(struct str s)
     int sc = 0;
     
     if ((sc = c_char(s))) {
-        s.text += sc;
-        s.size -= sc;
+        advance(&s, sc);
         
         for (;;) {
             if ((sc = c_char(s))) {
-                s.text += sc;
-                s.size -= sc;
+                advance(&s, sc);
             } else {
                 break;
             }
@@ -767,30 +731,25 @@ character_constant(struct str s)
     int ok = 0;
     
     if (s.size && s.text[0] == '\'') {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         ok = 1;
     } else if (s.size >= 2 && s.text[0] == 'L' && s.text[1] == '\'') {
-        s.text += 2;
-        s.size -= 2;
+        advance(&s, 2);
         ok = 1;
     } else if (s.size >= 2 && s.text[0] == 'u' && s.text[1] == '\'') {
-        s.text += 2;
-        s.size -= 2;
+        advance(&s, 2);
         ok = 1;
     } else if (s.size >= 2 && s.text[0] == 'U' && s.text[1] == '\'') {
-        s.text += 2;
-        s.size -= 2;
+        advance(&s, 2);
         ok = 1;
     }
     
     if (ok) {
         int ccs = c_char_sequence(s);
         if (ccs) {
-            s.text += ccs;
-            s.size -= ccs;
+            advance(&s, ccs);
             if (s.size && s.text[0] == '\'') {
-                s.size--;
+                advance(&s, 1);
                 return(start - s.size);
             }
         }
@@ -818,8 +777,7 @@ whitespace(struct str s)
     int start = s.size;
     
     while (s.size && (s.text[0] == ' ' || s.text[0] == '\t' || s.text[0] == '\n' || s.text[0] == '\r')) {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
     }
     
     return(start - s.size);
@@ -849,13 +807,11 @@ s_char_sequence(struct str s)
     int sc = 0;
     
     if ((sc = s_char(s))) {
-        s.text += sc;
-        s.size -= sc;
+        advance(&s, sc);
         
         for (;;) {
             if ((sc = s_char(s))) {
-                s.text += sc;
-                s.size -= sc;
+                advance(&s, sc);
             } else {
                 break;
             }
@@ -890,19 +846,16 @@ string_literal(struct str s)
     int start = s.size;
     
     int ep = encoding_prefix(s);
-    s.text += ep;
-    s.size -= ep;
+    advance(&s, ep);
     
     if (s.size && s.text[0] == '\"') {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         int scs = s_char_sequence(s);
-        s.text += scs;
-        s.size -= scs;
+        advance(&s, scs);
         
         if (s.size && s.text[0] == '\"') {
-            s.size--;
+            advance(&s, 1);
             return(start - s.size);
         }
     }
@@ -974,16 +927,14 @@ static int
 h_char_sequence(struct str s)
 {
     int start = s.size;
-    int sc = 0;
+    int hc = 0;
     
-    if ((sc = h_char(s))) {
-        s.text += sc;
-        s.size -= sc;
+    if ((hc = h_char(s))) {
+        advance(&s, hc);
         
         for (;;) {
-            if ((sc = h_char(s))) {
-                s.text += sc;
-                s.size -= sc;
+            if ((hc = h_char(s))) {
+                advance(&s, hc);
             } else {
                 break;
             }
@@ -999,16 +950,14 @@ static int
 q_char_sequence(struct str s)
 {
     int start = s.size;
-    int sc = 0;
+    int qc = 0;
     
-    if ((sc = q_char(s))) {
-        s.text += sc;
-        s.size -= sc;
+    if ((qc = q_char(s))) {
+        advance(&s, qc);
         
         for (;;) {
-            if ((sc = q_char(s))) {
-                s.text += sc;
-                s.size -= sc;
+            if ((qc = q_char(s))) {
+                advance(&s, qc);
             } else {
                 break;
             }
@@ -1024,13 +973,11 @@ static int
 header_name(struct str s)
 {
     if (s.size && s.text[0] == '<') {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         int hcs = h_char_sequence(s);
         if (hcs) {
-            s.text += hcs;
-            s.size -= hcs;
+            advance(&s, hcs);
             
             if (s.size && s.text[0] == '>') {
                 return(hcs + 2);
@@ -1039,13 +986,11 @@ header_name(struct str s)
     }
     
     if (s.size && s.text[0] == '\"') {
-        s.text++;
-        s.size--;
+        advance(&s, 1);
         
         int qcs = q_char_sequence(s);
         if (qcs) {
-            s.text += qcs;
-            s.size -= qcs;
+            advance(&s, qcs);
             
             if (s.size && s.text[0] == '\"') {
                 return(qcs + 2);
@@ -1064,18 +1009,15 @@ comment(struct str s)
     if (s.size >= 2) {
         if (s.text[0] == '/' && s.text[1] == '/') {
             /* single-line comment */
-            s.text += 2;
-            s.size -= 2;
+            advance(&s, 2);
             
             while (s.size) {
                 if (s.text[0] == '\n') {
-                    s.text++;
-                    s.size--;
+                    advance(&s, 1);
                     break;
                 }
                 
-                s.text++;
-                s.size--;
+                advance(&s, 1);
             }
             
             return(start - s.size);
@@ -1086,13 +1028,11 @@ comment(struct str s)
             
             while (s.size) {
                 if (s.size >= 2 && s.text[0] == '*' && s.text[1] == '/') {
-                    s.text += 2;
-                    s.size -= 2;
+                    advance(&s, 2);
                     break;
                 }
                 
-                s.text++;
-                s.size--;
+                advance(&s, 1);
             }
             
             return(start - s.size);
@@ -1109,8 +1049,7 @@ lex(char *text, int size)
     
     while (s.size) {
         int sym = whitespace(s);
-        s.text += sym;
-        s.size -= sym;
+        advance(&s, sym);
         
         if ((sym = comment(s))) {
             //printf("Comment: ");
@@ -1136,8 +1075,7 @@ lex(char *text, int size)
         //printf("%.*s\n", sym, s.text);
         
         if (sym) {
-            s.text += sym;
-            s.size -= sym;
+            advance(&s, sym);
         } else if (s.size) {
             fprintf(stderr, "Error!\n");
             break;
@@ -1168,22 +1106,17 @@ preprocess(char *data, int size)
 static void
 run(char *data, int size)
 {
-    struct timespec tp = { 0 };
-    
-    clock_gettime(CLOCK_MONOTONIC_RAW, &tp);
-    unsigned long long before = tp.tv_sec * 1000000ULL + tp.tv_nsec / 1000ULL;
-    
-    preprocess(data, size);
-    struct token *tokens = lex(data, size);
-    (void) tokens;
-    
-    clock_gettime(CLOCK_MONOTONIC_RAW, &tp);
-    
-    unsigned long long after = tp.tv_sec * 1000000ULL + tp.tv_nsec / 1000ULL;
+    unsigned long long before = usec_now();
+    {
+        preprocess(data, size);
+        struct token *tokens = lex(data, size);
+        (void) tokens;
+    }
+    unsigned long long after = usec_now();
     
-    unsigned long long dt = after - before;
+    float dt = after - before;
     
-    fprintf(stderr, "%.2fms, %.2fMB/s\n", (float) dt / 1000, (float) size / dt);
+    fprintf(stderr, "%.2fms, %.2fMB/s\n", dt / 1000, size / dt);
 }
 
 int