Update literals in the grammar reference

Add missing long literal suffix
Add binary integer literals
Introduce IntegerLiteral lexer rule, which is closer to the actual lexer

Issue #KT-22713 Fixed

compiler/frontend/src/org/jetbrains/kotlin/parsing/KotlinExpressionParsing.java

@@ -803,7 +803,6 @@ public class KotlinExpressionParsing extends AbstractKotlinParsing {
      *   : stringTemplate
      *   : NoEscapeString
      *   : IntegerLiteral
-     *   : LongLiteral
      *   : CharacterLiteral
      *   : FloatLiteral
      *   : "null"

grammar/src/expressions.grm

@@ -137,7 +137,6 @@ literalConstant
   : stringTemplate
   : NoEscapeString
   : IntegerLiteral
-  : HexadecimalLiteral
   : CharacterLiteral
   : FloatLiteral
   : "null"

grammar/src/lexical.grm

@@ -2,12 +2,23 @@
 # Lexical structure
 */
 
+[helper]
+LongSuffix
+  : "L"
+  ;
+
+IntegerLiteral
+  : DecimalLiteral LongSuffix?
+  : HexadecimalLiteral LongSuffix?
+  : BinaryLiteral LongSuffix?
+  ;
+
 [helper]
 Digit
   : ["0".."9"]
   ;
 
-IntegerLiteral
+DecimalLiteral
   : Digit
   : Digit (Digit | "_")* Digit
   ;
@@ -22,10 +33,19 @@ HexDigit
   ;
 
 HexadecimalLiteral
-  : "0x" HexDigit
+  : "0" ("x" | "X") HexDigit
-  : "0x" HexDigit (HexDigit | "_")* HexDigit
+  : "0" ("x" | "X") HexDigit (HexDigit | "_")* HexDigit
   ;
 
+[helper]
+BinaryDigit
+  : ("0" | "1")
+  ;
+
+BinaryLiteral
+  : "0" ("b" | "B") BinaryDigit
+  : "0" ("b" | "B") BinaryDigit (BinaryDigit | "_")* BinaryDigit
+
 CharacterLiteral
   : <character as in Java>
   ;