Reland merged out changes in D75026944

Summary:
I accidentally overwrote my changes in v3 of the above mentioned diff with the v4 version which merged out some of my intended edits.

Update the corresponding files with the right version of the code.

Reviewed By: vassilmladenov

Differential Revision: D76614862

fbshipit-source-id: 3cc038d44f1616bbce4bc32803428205c2469f83

Author: Niharika Devanathan

hphp/hack/src/hackc/assemble/assemble.rs

@@ -513,17 +513,15 @@ fn assemble_method(token_iter: &mut Lexer<'_>, adata: &AdataMap) -> Result<hhbc:
     })
 }
 
+fn parse_bool(token_iter: &mut Lexer<'_>) -> Result<bool> {
+    let tok = token_iter.expect(Token::is_identifier)?;
+    let id = tok.as_str()?;
+    let b = id.parse()?;
+    Ok(b)
+}
+
 fn assemble_single_tparam_info(token_iter: &mut Lexer<'_>) -> Result<TParamInfo> {
-    parse!(token_iter, "[" <name:assemble_class_name()> "," <num:num> "]");
-    let shadows_class_tparam = match num.into_number() {
-        Ok(b"0") => false,
-        Ok(b"1") => true,
-        _ => {
-            return Err(
-                token_iter.error(r#"Non "0"/"1" string in tparam info shadows class tparam"#)
-            );
-        }
-    };
+    parse!(token_iter, "[" <name:assemble_class_name()> <shadows_class_tparam:parse_bool> "]");
     Ok(TParamInfo {
         name,
         shadows_class_tparam,

hphp/hack/src/hackc/bytecode_printer/print.rs

@@ -535,13 +535,9 @@ fn print_tparam_info(w: &mut dyn Write, tparam_info: &[TParamInfo]) -> Result<()
         "<{}> ",
         fmt_separated(
             ",",
-            tparam_info.iter().map(|t| {
-                format!(
-                    "[{},{}]",
-                    t.name.as_str(),
-                    if t.shadows_class_tparam { 1 } else { 0 }
-                )
-            })
+            tparam_info
+                .iter()
+                .map(|t| { format!("[{} {}]", t.name.as_str(), t.shadows_class_tparam) })
         )
     )
 }

hphp/hack/src/hackc/ir/assemble/parse.rs

@@ -571,12 +571,7 @@ pub(crate) fn parse_readonly(tokenizer: &mut Tokenizer<'_>) -> Result<ReadonlyOp
 }
 
 pub(crate) fn parse_single_tparam_info(tokenizer: &mut Tokenizer<'_>) -> Result<TParamInfo> {
-    parse!(tokenizer, "[" <name:parse_class_name> "," <shadows:id> "]");
-    let shadows_class_tparam = match shadows.identifier() {
-        "0" => false,
-        "1" => true,
-        _ => return Err(shadows.bail("Unexpected token when parsing TParamInfo")),
-    };
+    parse!(tokenizer, "[" <name:parse_class_name> <shadows_class_tparam:parse_bool> "]");
     Ok(TParamInfo {
         name,
         shadows_class_tparam,
@@ -824,6 +819,12 @@ pub(crate) fn parse_usize(tokenizer: &mut Tokenizer<'_>) -> Result<usize> {
     Ok(i)
 }
 
+pub(crate) fn parse_bool(tokenizer: &mut Tokenizer<'_>) -> Result<bool> {
+    let t = tokenizer.expect_any_identifier()?;
+    let b = t.identifier().parse()?;
+    Ok(b)
+}
+
 pub(crate) fn parse_user_id(tokenizer: &mut Tokenizer<'_>) -> Result<(Vec<u8>, TokenLoc)> {
     let t = tokenizer.expect_any_token()?;
     let tloc = t.loc().clone();

hphp/hack/src/hackc/ir/print/formatters.rs

@@ -175,9 +175,9 @@ impl Display for FmtTParamInfo<'_> {
         let FmtTParamInfo(tpi) = *self;
         write!(
             f,
-            "[{},{}]",
+            "[{} {}]",
             FmtIdentifierId(tpi.name.as_bytes_id()),
-            if tpi.shadows_class_tparam { "1" } else { "0" }
+            tpi.shadows_class_tparam
         )
     }
 }

hphp/runtime/vm/as.cpp

@@ -2359,9 +2359,9 @@ std::vector<LowStringPtr> parse_tparam_names(AsmState& as) {
 }
 
 /*
- * directive-function : upper-bound-list attribute-list ?line-range type-info
- *                      identifier
- *                      parameter-list function-flags '{' function-body
+ * directive-function : attribute-list ?line-range tparam-names type-info
+ *                      identifier parameter-list function-flags '{'
+ *                      function-body
  *                    ;
  */
 void parse_function(AsmState& as) {
@@ -2410,9 +2410,9 @@ void parse_function(AsmState& as) {
 }
 
 /*
- * directive-method : shadowed-tparam-list upper-bound-list attribute-list
- *                      ?line-range tparam-names type-info identifier
- *                      parameter-list function-flags '{' function-body
+ * directive-method : attribute-list ?line-range tparam-names type-info
+ *                    identifier parameter-list function-flags '{'
+ *                    function-body
  *                  ;
  */
 void parse_method(AsmState& as) {
@@ -2785,9 +2785,8 @@ void parse_class_body(AsmState& as) {
 }
 
 /*
- * directive-class : upper-bound-list ?"top" attribute-list identifier
- *                   ?line-range extension-clause implements-clause '{'
- *                   class-body
+ * directive-class : attribute-list identifier ?line-range tparam-names
+ *                   extension-clause implements-clause '{' class-body
  *                 ;
  *
  * extension-clause : empty

hphp/runtime/vm/reified-generics.cpp

@@ -84,7 +84,7 @@ extractSizeAndPosFromReifiedAttribute(
       assertx(isIntType(v.m_type));
       if (k.m_data.num == 0) {
         len = (size_t) v.m_data.num;
-        assertx(len == typeParamNames.size());
+        always_assert(len == typeParamNames.size());
       } else {
         if (k.m_data.num % 3 == 1) {
           // This is the reified generic index