Merge pull request #2559 from mozilla/incoming

Incoming

Author: pcwalton

src/libcore/str.rs

@@ -592,7 +592,22 @@ Section: Comparing strings
 */
 
 #[doc = "Bytewise string equality"]
-pure fn eq(&&a: str, &&b: str) -> bool { a == b }
+pure fn eq(&&a: str, &&b: str) -> bool {
+    // FIXME: This should just be "a == b" but that calls into the shape code
+    // :(
+    let a_len = a.len();
+    let b_len = b.len();
+    if a_len != b_len { ret false; }
+    let mut end = uint::min(a_len, b_len);
+
+    let mut i = 0u;
+    while i < end {
+        if a[i] != b[i] { ret false; }
+        i += 1u;
+    }
+
+    ret true;
+}
 
 #[doc = "Bytewise less than or equal"]
 pure fn le(&&a: str, &&b: str) -> bool { a <= b }
@@ -1861,11 +1876,11 @@ impl extensions for str {
 
     Alphanumeric characters are determined by `char::is_alphanumeric`
     "]
-    #[inlune]
+    #[inline]
     fn is_alphanumeric() -> bool { is_alphanumeric(self) }
     #[inline]
     #[doc ="Returns the size in bytes not counting the null terminator"]
-    fn len() -> uint { len(self) }
+    pure fn len() -> uint { len(self) }
     #[doc = "
     Returns a slice of the given string from the byte range [`begin`..`end`)
 

src/libsyntax/parse/parser.rs

@@ -70,7 +70,9 @@ class parser {
     let mut token: token::token;
     let mut span: span;
     let mut last_span: span;
-    let buffer: dvec<{tok: token::token, span: span}>;
+    let mut buffer: [mut {tok: token::token, span: span}]/4;
+    let mut buffer_start: int;
+    let mut buffer_end: int;
     let mut restriction: restriction;
     let reader: reader;
     let keywords: hashmap<str, ()>;
@@ -86,7 +88,14 @@ class parser {
         self.token = tok0.tok;
         self.span = span0;
         self.last_span = span0;
-        self.buffer = dvec::dvec();
+        self.buffer = [mut
+            {tok: tok0.tok, span: span0},
+            {tok: tok0.tok, span: span0},
+            {tok: tok0.tok, span: span0},
+            {tok: tok0.tok, span: span0}
+        ]/4;
+        self.buffer_start = 0;
+        self.buffer_end = 0;
         self.restriction = UNRESTRICTED;
         self.reader = rdr;
         self.keywords = token::keyword_table();
@@ -98,12 +107,13 @@ class parser {
 
     fn bump() {
         self.last_span = self.span;
-        if self.buffer.len() == 0u {
+        if self.buffer_start == self.buffer_end {
             let next = lexer::next_token(self.reader);
             self.token = next.tok;
             self.span = mk_sp(next.chpos, self.reader.chpos);
         } else {
-            let next = self.buffer.shift();
+            let next = self.buffer[self.buffer_start];
+            self.buffer_start = (self.buffer_start + 1) & 3;
             self.token = next.tok;
             self.span = next.span;
         }
@@ -112,13 +122,21 @@ class parser {
         self.token = next;
         self.span = mk_sp(lo, hi);
     }
+    fn buffer_length() -> int {
+        if self.buffer_start <= self.buffer_end {
+            ret self.buffer_end - self.buffer_start;
+        }
+        ret (4 - self.buffer_start) + self.buffer_end;
+    }
     fn look_ahead(distance: uint) -> token::token {
-        while self.buffer.len() < distance {
+        let dist = distance as int;
+        while self.buffer_length() < dist {
             let next = lexer::next_token(self.reader);
             let sp = mk_sp(next.chpos, self.reader.chpos);
-            self.buffer.push({tok: next.tok, span: sp});
+            self.buffer[self.buffer_end] = {tok: next.tok, span: sp};
+            self.buffer_end = (self.buffer_end + 1) & 3;
         }
-        ret self.buffer[distance - 1u].tok;
+        ret copy self.buffer[(self.buffer_start + dist - 1) & 3].tok;
     }
     fn fatal(m: str) -> ! {
         self.sess.span_diagnostic.span_fatal(copy self.span, m)