PHP NorthWest 'All The Jumps' talk

jump-phpnw16.xml

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+<?xml version="1.0" encoding="utf-8"?>
+<presentation css="10gen-strict.css">
+<topic>PHP</topic>
+<title>It's All About the Jumps</title>
+<event>PHP North West 2016</event>
+<location>Manchester, UK</location>
+<date>October 1st, 2016</date>
+<speaker>Derick Rethans</speaker>
+<email>derick@php.net</email>
+<twitter>derickr</twitter>
+<joindin>https://joind.in/18836</joindin>
+
+<slide>slides/mongodb/title.xml</slide>
+<slide>slides/mongodb/me.xml</slide>
+
+<slide>slides/internals/title-agenda.xml</slide>
+
+<slide>slides/internals/title-stages.xml</slide>
+<!-- INTRODUCTION
+Compile stages:
+Parse script
+Create AST
+Convert to opcodes
+Run the code
+Opcache for caching
+-->
+<slide>slides/internals/stages.xml</slide>
+
+<!-- STAGES
+Parse
+- Show parser rules
+- Show "compiler" rules
+-->
+
+<slide>slides/internals/title-parsing.xml</slide>
+<slide>slides/internals/parse-state-machine.xml</slide>
+<slide>slides/internals/parse-tokenization.xml</slide>
+<slide>slides/internals/scanner.xml</slide>
+<slide>slides/internals/scanner-rules.xml</slide>
+<slide>slides/internals/ast.xml</slide>
+<slide>slides/internals/ast1.xml</slide>
+<slide>slides/internals/scanner-ast.xml</slide>
+<slide>slides/internals/scanner-ast2.xml</slide>
+<slide>slides/internals/bytecode0.xml</slide>
+<slide>slides/internals/bytecode½.xml</slide>
+<slide>slides/internals/bytecode1.xml</slide>
+
+<slide>slides/internals/jumps.xml</slide>
+
+<!--
+AST
+- Show AST for various control structures
+
+Opcodes
+- Show AST for the same control structures
+-->
+
+<slide>slides/internals/jumps-if.xml</slide>
+<slide>slides/internals/jumps-if-else.xml</slide>
+
+<slide>slides/internals/rings.xml</slide>
+<slide>slides/internals/jumps-for.xml</slide>
+<slide>slides/internals/jumps-for-rewritten.xml</slide>
+<slide>slides/internals/jumps-while.xml</slide>
+<slide>slides/internals/jumps-do-while.xml</slide>
+<slide>slides/internals/jumps-foreach.xml</slide>
+<slide>slides/internals/jumps-complex.xml</slide>
+<slide>slides/internals/loops.xml</slide>
+<slide>slides/internals/jumps-complex-dot.xml</slide>
+
+<!--
+Try/Catch nonsense
+- FASTCALL/FASTRET
+-->
+<slide>slides/internals/catch.xml</slide>
+<slide>slides/internals/jumps-try-catch.xml</slide>
+
+<!--
+Dead code analysis
+- Show how Xdebug does it through VLD
+-->
+<slide>slides/internals/deadcode.xml</slide>
+<slide>slides/internals/deadcode-vld.xml</slide>
+
+<!--
+Path analysis
+- Branch and Path
+-->
+<slide>slides/internals/branches.xml</slide>
+<slide>slides/xdebug/vld-path-2-paths.xml</slide>
+<slide>slides/xdebug/vld-path-4-code.xml</slide>
+<slide>slides/xdebug/vld-path-4-output.xml</slide>
+
+<slide>slides/xdebug/vld-path-3-code.xml</slide>
+<slide>slides/xdebug/vld-path-3-output.xml</slide>
+<slide>slides/xdebug/vld-path-3-paths.xml</slide>
+
+<!-- Conclusion
+
+Code -> Tokens -> AST -> opode
+
+Transformation of control structures
+
+Useful implementations 
+
+-->
+<slide>slides/internals/recap.xml</slide>
+<slide>slides/internals/recap-content.xml</slide>
+
+
+
+<slide>slides/mongodb/questions.xml</slide>
+
+<slide>slides/mongodb/resources.xml</slide>
+
+</presentation>

slides/internals/ast.xml

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+<slide style="title">
+<title>Abstract Syntax Tree</title>
+<image align="center" filename="abstract-tree.jpg" attr=""/>
+</slide>

slides/internals/ast1.xml

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+<slide>
+<title>Abstract Syntax Tree</title>
+
+<list>
+    <bullet>An AST describes the structure of the parser script</bullet>
+    <bullet>Each node is a language construct</bullet>
+    <bullet>Nested structures are represented through a tree</bullet>
+    <bullet>Not all the original information from the original source code is kept</bullet>
+    <bullet>The *php-ast* extension on Nikita Popov's (nikic) GitHub account can visualize them</bullet>
+    <bullet>Optimisations are possible by modifications of the tree</bullet>
+</list>
+</slide>

slides/internals/branches.xml

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+<slide style="title">
+<title>Branch Analysis</title>
+<image align="center" filename="branches.jpg" attr="Sergey Kochkarev - https://www.flickr.com/photos/skochkar/24747666840/ - Public Domain"/>
+</slide>

slides/internals/bytecode0.xml

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+<slide style="title">
+<title>Byte Code</title>
+<image align="center" filename="bytecode.jpg" attr=""/>
+</slide>

slides/internals/bytecode1.xml

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+<slide>
+<title>AST is converted to bytecode</title>
+
+<example inline="1">
+1: AST_METHOD
+    flags: MODIFIER_PUBLIC (256)
+    name: |00dd00|__construct|
+    params: AST_PARAM_LIST
+        0: AST_PARAM
+            name: |0000dd|"name"|
+    stmts: AST_STMT_LIST
+        0: |dd00dd|AST_ASSIGN|
+            var: |00dddd|AST_PROP|
+                expr: AST_VAR
+                    name: |00dddd|"this"|
+                prop: |00dddd|"name"|
+            expr: AST_VAR
+                name: |0000dd|"name"|
+</example>
+<br/>
+<example inline="1">
+compiled vars:  |0000dd|!0 = $name|
+line     #* E I O op                           fetch          ext  return  operands
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+   8     0  E >   EXT_NOP                                                  
+         1        RECV                                             |0000dd|!0|      
+  10     2        EXT_STMT                                                 
+         3        |dd00dd|ASSIGN||00dddd|_OBJ|                                               |00dddd|'name'|
+         4        |dd00dd|OP_DATA|                                                  |0000dd|!0|
+  11     5        EXT_STMT                                                 
+         6      > RETURN                                                   null
+</example>
+</slide>

slides/internals/bytecode½.xml

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+<slide>
+<title>Byte Code</title>
+
+<list>
+    <bullet>In PHP also called Opcodes</bullet>
+    <bullet>Each function, method, or main body is represented by an Oparray</bullet>
+    <bullet>Each Oparray contains Opcodes with instructions for the Zend Engine</bullet>
+    <bullet>The Zend Engine executes each opcode in turn</bullet>
+    <bullet>Very similar to Assembler instructions</bullet>
+    <bullet>You can visualize them with the PECL *vld* extension</bullet>
+</list>
+</slide>

slides/internals/catch.xml

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+<slide style="title">
+<title>Exceptions (Try/Catch)</title>
+<image align="center" filename="catch.jpg" attr="Soggydan Benenovitch (https://www.flickr.com/photos/38518750@N00/4858510277)"/>
+</slide>

slides/internals/deadcode-vld.xml

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+<slide>
+<title>Dead Code</title>
+
+<image align="right" filename="deadcode.png"/>
+
+<example inline="1">&amp;lt;?php
+if ( $a &amp;lt; 42 ) {
+	echo "fourty";
+	return;
+	*echo "two";*
+}
+</example>
+
+<example inline="1">
+line   #* E I O op             return  operands
+   2   0  E >   IS_SMALLER     ~1      !0, 42
+       1      > JMPZ                   ~1, ->5
+   3   2    >   ECHO                   'fourty'
+   4   3      > RETURN                 null
+   5   *4\*       ECHO                   'two'*
+       5    > > RETURN                 1
+</example>
+
+<list>
+<bullet>Follow all branches</bullet>
+<bullet>Find unreached opcodes</bullet>
+</list>
+</slide>

slides/internals/deadcode.xml

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+<slide style="title">
+<title>Dead Code</title>
+<image align="center" filename="rosetta.jpg" attr="Cristian Bortes - https://www.flickr.com/photos/bortescristian/2931856207 - CC-BY"/>
+</slide>

slides/internals/jumps-complex-dot.xml

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+<slide>
+<title>Complex Loops</title>
+
+<image align="right" filename="complex-dot.png"/>
+
+<example inline="1">&amp;lt;?php
+$a = [ 2.7, 4.9 ];
+|dd0000|foreach ( $a as $key => $value )| {
+	|00dd00|if ( $value &amp;lt; 3 ) {|
+		echo $key;
+	} else {
+		|0000dd|if ( $key > 0 ) {|
+			echo $value;
+		}
+	}
+}
+</example>
+
+<example inline="1">
+line     #* E I O op            return  operands
+   2     0  E >   ASSIGN                !0, &amp;lt;array>
+   3     1      > |dd0000|FE_RESET_R    $4      !0, ->12|
+         2    > > |dd0000|FE_FETCH_R    ~5      $4, !1, ->12|
+         3    >   |dd0000|ASSIGN                !2, ~5|
+   4     4        |00dd00|IS_SMALLER    ~7      !1, 3|
+         5      > |00dd00|JMPZ                  ~7, ->8|
+   5     6    >   ECHO                  !2
+         7      > |00dd00|JMP                   ->11|
+   7     8    >   |0000dd|IS_SMALLER    ~8      0, !2|
+         9      > |0000dd|JMPZ                  ~8, ->11|
+   8    10    >   ECHO                  !1
+        11    > > |dd0000|JMP                   ->2|
+        12    >   |dd0000|FE_FREE               $4|
+        13      > RETURN                1
+</example>
+</slide>

slides/internals/jumps-complex.xml

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+<slide>
+<title>Complex Loops</title>
+
+<example inline="1">&amp;lt;?php
+$a = [ 2.7, 4.9 ];
+foreach ( $a as $key => $value ) {
+	if ( $value &amp;lt; 3 ) {
+		echo $key;
+	} else {
+		if ( $key > 0 ) {
+			echo $value;
+		}
+	}
+}
+</example>
+
+<example inline="1">line     #* E I O op                           fetch          ext  return  operands
+   2     0  E >   ASSIGN                                                   !0, &amp;lt;array>
+   3     1      > FE_RESET_R                                       $4      !0, ->12
+         2    > > FE_FETCH_R                                       ~5      $4, !1, ->12
+         3    >   ASSIGN                                                   !2, ~5
+   4     4        IS_SMALLER                                       ~7      !1, 3
+         5      > JMPZ                                                     ~7, ->8
+   5     6    >   ECHO                                                     !2
+         7      > JMP                                                      ->11
+   7     8    >   IS_SMALLER                                       ~8      0, !2
+         9      > JMPZ                                                     ~8, ->11
+   8    10    >   ECHO                                                     !1
+        11    > > JMP                                                      ->2
+        12    >   FE_FREE                                                  $4
+        13      > RETURN                                                   1
+</example>
+</slide>

slides/internals/jumps-do-while.xml

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+<slide>
+<title>DO .. WHILE</title>
+
+<example inline="1">&amp;lt;?php
+|dd0000|$i = 10;|
+do {
+    |0000dd|echo $i;|
+} while ( |00dd00|--$i| );
+</example>
+
+<example inline="1">compiled vars:  !0 = $i
+line     #* E I O op                           fetch          ext  return  operands
+   2     0  E >   EXT_STMT                                                 
+         1        |dd0000|ASSIGN                                                   !0, 10|
+   3     2        NOP                                                      
+   4     3    >   EXT_STMT                                                 
+         4        |0000dd|ECHO                                                     !0|
+   5     5        |00dd00|PRE_DEC                                          $2      !0|
+         6      > |00dd00|JMPNZ                                                    $2, ->3|
+         7    > > RETURN                                                   1
+</example>
+</slide>

slides/internals/jumps-for-rewritten.xml

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+<slide>
+<title>FOR (rewritten)</title>
+
+<example inline="1">
+for ( |dd0000|$i = 0|; |00dd00|$i &amp;lt; 42|; |0000dd|++$i| ) {
+    |dd00dd|echo $i;|
+}
+</example>
+
+<example inline="1">
+	|dd0000|$i = 0;|
+	goto COND;
+STMT:
+	|dd00dd|echo $i;|
+	|0000dd|++$i;|
+COND:
+	|00dd00|$_ = $i &amp;lt; 42;|
+	|00dd00|if ( ! $_ ) {|
+		|00dd00|goto STMT;|
+	|00dd00|}|
+</example>
+
+<example inline="1">compiled vars:  !0 = $i
+line     #* E I O op                           fetch          ext  return  operands
+   2     0  E >   EXT_STMT                                                 
+         1        |dd0000|ASSIGN                                                   !0, 0|
+         2      > |dd0000|JMP                                                      ->6|
+   4     3    >   |dd00dd|EXT_STMT                                                 |
+         4        |dd00dd|ECHO                                                     !0|
+   2     5        |0000dd|PRE_INC                                                  !0|
+         6    >   |00dd00|IS_SMALLER                                       ~3      !0, 42|
+         7        |00dd00|EXT_STMT                                                 |
+         8      > |00dd00|JMPNZ                                                    ~3, ->3|
+         9    > > RETURN                                                   1
+</example>
+</slide>

slides/internals/jumps-for.xml

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+<slide>
+<title>FOR</title>
+
+<table class="two">
+<tr>
+
+<td>
+<example inline="1">
+&amp;lt;?php
+for ( |dd0000|$i = 0|; |00dd00|$i &amp;lt; 42|; |0000dd|++$i| ) {
+    |dd00dd|echo $i;|
+}
+</example>
+</td>
+
+<td>
+<example inline="1">
+        |dd0000|init: AST_EXPR_LIST|
+            0: AST_ASSIGN
+                var: AST_VAR
+                    name: "i"
+                expr: 0
+        |00dd00|cond: AST_EXPR_LIST|
+            0: AST_BINARY_OP
+                flags: BINARY_IS_SMALLER (19)
+                left: AST_VAR
+                    name: "i"
+                right: 42
+        |0000dd|loop: AST_EXPR_LIST|
+            0: AST_PRE_INC
+                var: AST_VAR
+                    name: "i"
+        |dd00dd|stmts: …|</example>
+</td>
+</tr></table>
+
+<example inline="1">compiled vars:  !0 = $i
+line     #* E I O op                           fetch          ext  return  operands
+   2     0  E >   EXT_STMT                                                 
+         1        |dd0000|ASSIGN                                                   !0, 0|
+         2      > |dd0000|JMP                                                      ->6|
+   4     3    >   |dd00dd|EXT_STMT                                                 |
+         4        |dd00dd|ECHO                                                     !0|
+   2     5        |0000dd|PRE_INC                                                  !0|
+         6    >   |00dd00|IS_SMALLER                                       ~3      !0, 42|
+         7        |00dd00|EXT_STMT                                                 |
+         8      > |00dd00|JMPNZ                                                    ~3, ->3|
+         9    > > RETURN                                                   1
+</example>
+</slide>

slides/internals/jumps-foreach.xml

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+<slide>
+<title>FOREACH</title>
+
+<example inline="1">&amp;lt;?php
+|dd0000|$a = [ 2.7, 4.9 ];|
+|00dd00|foreach ( $a as $key => $value )| {
+    echo $key, $value;
+}
+</example>
+
+<example inline="1">
+compiled vars:  !0 = $a, !1 = $value, !2 = $key
+line     #* E I O op                           fetch          ext  return  operands
+   2     0  E >   EXT_STMT                                                 
+         1        |dd0000|ASSIGN                                                   !0, &amp;lt;array>|
+   3     2        EXT_STMT                                                 
+         3      > |00dd00|FE_RESET_R                                       $4      !0,| |dd00dd|->11|
+         *4*    > > |00dd00|FE_FETCH_R                                       ~5      $4, !1,| |dd00dd|->11|
+         5    >   |00dd00|ASSIGN                                                   !2, ~5|
+   4     6        EXT_STMT                                                 
+         7        ECHO                                                     !2
+         8        EXT_STMT                                                 
+         9        ECHO                                                     !1
+        10      > *JMP                                                      ->4*
+        |dd00dd|11    >   FE_FREE                                                  $4|
+        12      > RETURN                                                   1
+</example>
+</slide>

slides/internals/jumps-if-else.xml

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+<slide>
+<title>IF with ELSE</title>
+
+<table class="two">
+<tr>
+
+<td>
+<example inline="1">
+if ( |0000dd|$a| == |00dd00|3.1415926| ) {
+    echo "Circles";
+} else {
+    echo "Squares";
+}
+</example>
+</td>
+
+<td>
+<example inline="1">AST_STMT_LIST
+    0: AST_IF
+        0: AST_IF_ELEM
+            cond: AST_BINARY_OP
+                flags: BINARY_IS_EQUAL (17)
+                left: AST_VAR
+                    name: "a"
+                right: 3.1415926
+            stmts: AST_STMT_LIST
+                0: AST_ECHO
+                    expr: "Circles"
+        1: AST_IF_ELEM
+            cond: null
+            stmts: AST_STMT_LIST
+                0: AST_ECHO
+                    expr: "Squares"</example>
+</td>
+</tr></table>
+
+<example inline="1">
+compiled vars:  |0000dd|!0 = $a|
+line     #* E I O op            return  operands
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+   2     0  E >   EXT_STMT              
+         1        IS_EQUAL      ~1      |0000dd|!0|, 3.14159
+         2      > *JMPZ*                  ~1, ->|00dddd|6|
+   3     3    >   EXT_STMT              
+         4        ECHO                  'Circles'
+         5      > *JMP*                   ->|00dddd|8|
+   5     |00dddd|6|    >   EXT_STMT              
+         7        ECHO                  'Squares'
+         |00dddd|8|    > > RETURN                1
+</example>
+</slide>

slides/internals/jumps-if.xml

@@ -0,0 +1,36 @@
+<slide>
+<title>IF</title>
+
+<example inline="1">
+if ( |0000dd|$a| == |00dd00|42| )
+{
+    echo "To life, the universe, and everything.\n";
+}
+</example>
+
+<example inline="1">
+AST_STMT_LIST
+    0: AST_IF
+        0: AST_IF_ELEM
+            cond: AST_BINARY_OP
+                flags: BINARY_IS_EQUAL (17)
+                left: AST_VAR
+                    |0000dd|name: "a"|
+                right: |00dd00|42|
+            stmts: AST_STMT_LIST
+                0: AST_ECHO
+                    expr: "To life, the universe, and everything.
+</example>
+
+<example inline="1">
+compiled vars:  |0000dd|!0 = $a|
+line     #* E I O op            return  operands
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+   2     0  E >   EXT_STMT              
+         1        IS_EQUAL      |dd0000|~1|      |0000dd|!0|, |00dd00|42|
+         2      > *JMPZ*                  |dd0000|~1|, ->|00dddd|5|
+   4     3    >   EXT_STMT              
+         4        ECHO                  'To+life%2C+the+universe%2C+and+everything.%0A'
+         |00dddd|5|    > > RETURN                1
+</example>
+</slide>

slides/internals/jumps-try-catch.xml

@@ -0,0 +1,33 @@
+<slide>
+<title>TRY … CATCH … FINALLY</title>
+
+<example inline="1">&amp;lt;?php
+try {
+    echo "in try";
+} *catch* ( Exception1 $e ) {
+    echo "exception 1 thrown";
+} *catch* ( Exception2 $e ) {
+    echo "exception 2 thrown";
+|00dd00|} finally {|
+    |0000dd|echo "in finally";|
+}
+echo "after";
+</example>
+
+<example inline="1">
+line     #* E I O op            return  operands
+   3     0  E >   ECHO                  'in+try'
+         1      > JMP                   |00dd00|->7|
+   4     2  *E > > CATCH*                 'Exception1', !0, |dd00dd|->5|
+   5     3    >   ECHO                  'exception+1+thrown'
+         4      > JMP                   |00dd00|->7|
+   6     |dd00dd|5|  *E > > CATCH*                 'Exception2', !0
+   7     6    >   ECHO                  'exception+2+thrown'
+   8     |00dd00|7    > > FAST_CALL|             ->9
+         8    > > JMP                   ->11
+   9     |0000dd|9    >   ECHO                  'in+finally'|
+        |0000dd|10      > FAST_RET|              
+  11    11    >   ECHO                  'after'
+        12      > RETURN                1
+</example>
+</slide>

slides/internals/jumps-while.xml

@@ -0,0 +1,23 @@
+<slide>
+<title>WHILE</title>
+
+<example inline="1">&amp;lt;?php
+|dd0000|$i = 10;|
+*while* ( |00dd00|--$i| ) {
+    |0000dd|echo $i;|
+}
+</example>
+
+<example inline="1">compiled vars:  !0 = $i
+line     #* E I O op                           fetch          ext  return  operands
+   2     0  E >   EXT_STMT                                                 
+         1        |dd0000|ASSIGN                                                   !0, 10|
+   3     2        EXT_STMT                                                 
+         3      > *JMP*                                                      ->|dd00dd|6|
+   4     4    >   EXT_STMT                                                 
+         5        |0000dd|ECHO                                                     !0|
+   3     |dd00dd|6|    >   |00dd00|PRE_DEC                                          $2      !0|
+         7      > |00dd00|JMPNZ                                                    $2, ->4|
+         8    > > RETURN                                                   1
+</example>
+</slide>

slides/internals/jumps.xml

@@ -0,0 +1,4 @@
+<slide style="title">
+<title>Jumps</title>
+<image align="center" filename="jumps.jpg" attr="Thor-Wiggo Skille (http://www.nfk.no/Artikkel.aspx?AId=25071&amp;back=1&amp;MId1=4557&amp;MId2=&amp;MId3=&amp;)"/>
+</slide>

slides/internals/loops.xml

@@ -0,0 +1,4 @@
+<slide style="title">
+<title>Complex Loops</title>
+<image align="center" filename="loops.png" attr="http://xkcd.com/657"/>
+</slide>

slides/internals/parse-state-machine.xml

@@ -0,0 +1,17 @@
+<slide>
+<title>Tokenization</title>
+
+<list>
+    <bullet>It's a big state machine starting with %INITIAL%</bullet>
+    <bullet>States: %INITIAL%, %ST_IN_SCRIPTING%, %ST_DOUBLE_QUOTES%, %ST_NOWDOC%…</bullet>
+    <bullet>Tokens can change the state:
+        <example><![CDATA[<INITIAL>"<?php"([ \t]|{NEWLINE}) {
+    HANDLE_NEWLINE(yytext[yyleng-1]);
+    BEGIN(ST_IN_SCRIPTING);
+    RETURN_TOKEN(T_OPEN_TAG);
+} ]]></example>
+    </bullet>
+    <bullet>No *meaning* is given to these tokens</bullet>
+    <bullet>PHP comes with a *tokenizer* extension</bullet>
+</list>
+</slide>

slides/internals/parse-tokenization.xml

@@ -0,0 +1,49 @@
+<slide>
+<title>Tokenization</title>
+
+<div effect="fade-out">
+<blurb>Example script:</blurb>
+<example inline="1"><![CDATA[&lt;?php
+namespace DramIO;
+class Whisky
+{
+    private $name;
+
+    public function __construct( $name )
+    {
+        $this->name = $name;
+    }
+
+    public function drink()
+    {
+        echo "Drinking {$this->name}\n";
+    }
+}
+?>]]></example>
+</div>
+
+<div effect="fade-in">
+<blurb>Example script:</blurb>
+<example inline="1"><![CDATA[&lt;?php
+namespace DramIO;
+class Whisky
+{
+    private $name;
+
+    public function __construct($name)
+    {
+        $this->name = $name;␃]]></example>
+<blurb>In tokens:</blurb>
+<example inline="1"><![CDATA[*T_OPEN_TAG* &lt;?php
+*T_NAMESPACE* |777777|T_WS| *T_NS_SEPARATOR* *T_STRING* DramIO ; |777777|T_WS| 
+*T_CLASS* |777777|T_WS| *T_NS_SEPARATOR* *T_STRING* Whisky |777777|T_WS|
+{ |777777|T_WS| 
+    *T_PRIVATE* |777777|T_WS| *T_VARIABLE* $name ; |777777|T_WS| 
+
+    *T_PUBLIC* |777777|T_WS| *T_FUNCTION* |777777|T_WS| *T_STRING* __construct ( *T_VARIABLE* $name ) |777777|T_WS| 
+    { |777777|T_WS| 
+       *T_VARIABLE* $this *T_OBJECT_OPERATOR* -> *T_STRING* name |777777|T_WS| = |777777|T_WS| *T_VARIABLE* $name ;
+    ]]></example>
+</div>
+
+</slide>

slides/internals/recap-content.xml

@@ -0,0 +1,18 @@
+<slide>
+<title>Recap</title>
+
+<list>
+	<bullet>Stages:<br/>Code → Tokens → Parsing → AST → Byte Code</bullet>
+	<bullet>All looping structures are jumps</bullet>
+	<bullet>Code analysis for Fun and Profit</bullet>
+</list>
+
+<break/>
+<blurb>*Tools*</blurb>
+<list>
+	<bullet>PHP's tokenizer: http://php.net/tokenizer</bullet>
+	<bullet>Nikita's AST extension: https://github.com/nikic/php-ast</bullet>
+	<bullet>VLD: https://pecl.php.net/vld</bullet>
+</list>
+
+</slide>

slides/internals/recap.xml

@@ -0,0 +1,4 @@
+<slide style="title">
+<title>Recap</title>
+<image align="center" filename="recap.jpg" attr="Jens Johnsson - https://www.pexels.com/photo/mountains-nature-arrow-guide-66100/ - CC0"/>
+</slide>

slides/internals/rings.xml

@@ -0,0 +1,4 @@
+<slide style="title">
+<title>Rings</title>
+<image align="center" filename="ring.png" attr="© OpenStreetMap contributors"/>
+</slide>

slides/internals/scanner-ast.xml

@@ -0,0 +1,327 @@
+<slide>
+<title>Abstract Syntax Tree</title>
+
+<blurb>Raw output from %ast\parse_code% function:</blurb>
+<example>
+object(ast\Node)#1 (4) {
+  ["kind"]=>
+  int(133)
+  ["flags"]=>
+  int(0)
+  ["lineno"]=>
+  int(1)
+  ["children"]=>
+  array(2) {
+    [0]=>
+    object(ast\Node)#2 (4) {
+      ["kind"]=>
+      int(257)
+      ["flags"]=>
+      int(0)
+      ["lineno"]=>
+      int(2)
+      ["children"]=>
+      array(1) {
+        ["name"]=>
+        object(ast\Node)#3 (4) {
+          ["kind"]=>
+          int(2048)
+          ["flags"]=>
+          int(2)
+          ["lineno"]=>
+          int(2)
+          ["children"]=>
+          array(1) {
+            ["name"]=>
+            string(6) "DramIO"
+          }
+        }
+      }
+    }
+    [1]=>
+    object(ast\Node\Decl)#4 (7) {
+      ["kind"]=>
+      int(69)
+      ["flags"]=>
+      int(0)
+      ["lineno"]=>
+      int(4)
+      ["children"]=>
+      array(3) {
+        ["extends"]=>
+        NULL
+        ["implements"]=>
+        NULL
+        ["stmts"]=>
+        object(ast\Node)#5 (4) {
+          ["kind"]=>
+          int(133)
+          ["flags"]=>
+          int(0)
+          ["lineno"]=>
+          int(5)
+          ["children"]=>
+          array(3) {
+            [0]=>
+            object(ast\Node)#6 (4) {
+              ["kind"]=>
+              int(139)
+              ["flags"]=>
+              int(1024)
+              ["lineno"]=>
+              int(6)
+              ["children"]=>
+              array(1) {
+                [0]=>
+                object(ast\Node)#7 (4) {
+                  ["kind"]=>
+                  int(774)
+                  ["flags"]=>
+                  int(0)
+                  ["lineno"]=>
+                  int(6)
+                  ["children"]=>
+                  array(2) {
+                    ["name"]=>
+                    string(4) "name"
+                    ["default"]=>
+                    NULL
+                  }
+                }
+              }
+            }
+            [1]=>
+            object(ast\Node\Decl)#8 (7) {
+              ["kind"]=>
+              int(68)
+              ["flags"]=>
+              int(256)
+              ["lineno"]=>
+              int(8)
+              ["children"]=>
+              array(4) {
+                ["params"]=>
+                object(ast\Node)#9 (4) {
+                  ["kind"]=>
+                  int(137)
+                  ["flags"]=>
+                  int(0)
+                  ["lineno"]=>
+                  int(8)
+                  ["children"]=>
+                  array(1) {
+                    [0]=>
+                    object(ast\Node)#10 (4) {
+                      ["kind"]=>
+                      int(773)
+                      ["flags"]=>
+                      int(0)
+                      ["lineno"]=>
+                      int(8)
+                      ["children"]=>
+                      array(3) {
+                        ["type"]=>
+                        NULL
+                        ["name"]=>
+                        string(4) "name"
+                        ["default"]=>
+                        NULL
+                      }
+                    }
+                  }
+                }
+                ["uses"]=>
+                NULL
+                ["stmts"]=>
+                object(ast\Node)#11 (4) {
+                  ["kind"]=>
+                  int(133)
+                  ["flags"]=>
+                  int(0)
+                  ["lineno"]=>
+                  int(9)
+                  ["children"]=>
+                  array(1) {
+                    [0]=>
+                    object(ast\Node)#12 (4) {
+                      ["kind"]=>
+                      int(517)
+                      ["flags"]=>
+                      int(0)
+                      ["lineno"]=>
+                      int(10)
+                      ["children"]=>
+                      array(2) {
+                        ["var"]=>
+                        object(ast\Node)#13 (4) {
+                          ["kind"]=>
+                          int(513)
+                          ["flags"]=>
+                          int(0)
+                          ["lineno"]=>
+                          int(10)
+                          ["children"]=>
+                          array(2) {
+                            ["expr"]=>
+                            object(ast\Node)#14 (4) {
+                              ["kind"]=>
+                              int(256)
+                              ["flags"]=>
+                              int(0)
+                              ["lineno"]=>
+                              int(10)
+                              ["children"]=>
+                              array(1) {
+                                ["name"]=>
+                                string(4) "this"
+                              }
+                            }
+                            ["prop"]=>
+                            string(4) "name"
+                          }
+                        }
+                        ["expr"]=>
+                        object(ast\Node)#15 (4) {
+                          ["kind"]=>
+                          int(256)
+                          ["flags"]=>
+                          int(0)
+                          ["lineno"]=>
+                          int(10)
+                          ["children"]=>
+                          array(1) {
+                            ["name"]=>
+                            string(4) "name"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                ["returnType"]=>
+                NULL
+              }
+              ["endLineno"]=>
+              int(11)
+              ["name"]=>
+              string(11) "__construct"
+              ["docComment"]=>
+              NULL
+            }
+            [2]=>
+            object(ast\Node\Decl)#16 (7) {
+              ["kind"]=>
+              int(68)
+              ["flags"]=>
+              int(256)
+              ["lineno"]=>
+              int(13)
+              ["children"]=>
+              array(4) {
+                ["params"]=>
+                object(ast\Node)#17 (4) {
+                  ["kind"]=>
+                  int(137)
+                  ["flags"]=>
+                  int(0)
+                  ["lineno"]=>
+                  int(13)
+                  ["children"]=>
+                  array(0) {
+                  }
+                }
+                ["uses"]=>
+                NULL
+                ["stmts"]=>
+                object(ast\Node)#18 (4) {
+                  ["kind"]=>
+                  int(133)
+                  ["flags"]=>
+                  int(0)
+                  ["lineno"]=>
+                  int(14)
+                  ["children"]=>
+                  array(1) {
+                    [0]=>
+                    object(ast\Node)#19 (4) {
+                      ["kind"]=>
+                      int(282)
+                      ["flags"]=>
+                      int(0)
+                      ["lineno"]=>
+                      int(15)
+                      ["children"]=>
+                      array(1) {
+                        ["expr"]=>
+                        object(ast\Node)#20 (4) {
+                          ["kind"]=>
+                          int(131)
+                          ["flags"]=>
+                          int(0)
+                          ["lineno"]=>
+                          int(15)
+                          ["children"]=>
+                          array(3) {
+                            [0]=>
+                            string(9) "Drinking "
+                            [1]=>
+                            object(ast\Node)#21 (4) {
+                              ["kind"]=>
+                              int(513)
+                              ["flags"]=>
+                              int(0)
+                              ["lineno"]=>
+                              int(15)
+                              ["children"]=>
+                              array(2) {
+                                ["expr"]=>
+                                object(ast\Node)#22 (4) {
+                                  ["kind"]=>
+                                  int(256)
+                                  ["flags"]=>
+                                  int(0)
+                                  ["lineno"]=>
+                                  int(15)
+                                  ["children"]=>
+                                  array(1) {
+                                    ["name"]=>
+                                    string(4) "this"
+                                  }
+                                }
+                                ["prop"]=>
+                                string(4) "name"
+                              }
+                            }
+                            [2]=>
+                            string(1) "
+"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                ["returnType"]=>
+                NULL
+              }
+              ["endLineno"]=>
+              int(16)
+              ["name"]=>
+              string(5) "drink"
+              ["docComment"]=>
+              NULL
+            }
+          }
+        }
+      }
+      ["endLineno"]=>
+      int(17)
+      ["name"]=>
+      string(6) "Whisky"
+      ["docComment"]=>
+      NULL
+    }
+  }
+}
+</example>
+</slide>

slides/internals/scanner-ast2.xml

@@ -0,0 +1,88 @@
+<slide>
+<title>Abstract Syntax Tree (formatted)</title>
+
+<div effect="fade-out">
+<example inline="1">AST_STMT_LIST
+    0: AST_CONST
+        …
+    1: *AST_CLASS*
+        flags: 0
+        name: Whisky
+        extends: null
+        implements: null
+        stmts: AST_STMT_LIST
+            0: AST_PROP_DECL
+                flags: MODIFIER_PRIVATE (1024)
+                0: AST_PROP_ELEM
+                    name: "name"
+                    default: null
+            1: *AST_METHOD*
+                flags: *MODIFIER_PUBLIC* (256)
+                name: *__construct*
+                params: AST_PARAM_LIST
+                    0: AST_PARAM
+                        flags: 0
+                        type: null
+                        name: "name"
+                        default: null
+                uses: null
+                *stmts: AST_STMT_LIST*
+                    0: AST_ASSIGN
+                        var: AST_PROP
+                            expr: AST_VAR
+                                name: "this"
+                            prop: "name"
+                        expr: AST_VAR
+                            name: "name"
+                returnType: null
+            2: AST_METHOD
+                flags: MODIFIER_PUBLIC (256)
+                name: drink
+                params: AST_PARAM_LIST
+                uses: null
+                stmts: AST_STMT_LIST
+                    0: AST_ECHO
+                        expr: AST_ENCAPS_LIST
+                            0: "Drinking "
+                            1: AST_PROP
+                                expr: AST_VAR
+                                    name: "this"
+                                prop: "name"
+                            2: "
+                            "
+                returnType: null</example>
+</div>
+
+<div effect="fade-in">
+<example inline="1">
+|0000dd|public| function |00dd00|__construct|( |0000dd|$name| )
+{
+    |00dddd|$this->name| |dd00dd|=| |ff0000|$name|
+}
+</example>
+
+<br/>
+
+<example inline="1">
+1: AST_METHOD
+    flags: MODIFIER_PUBLIC (256)
+    name: |00dd00|__construct|
+    params: AST_PARAM_LIST
+        0: AST_PARAM
+            flags: 0
+            type: null
+            name: |0000dd|"name"|
+            default: null
+    uses: null
+    stmts: AST_STMT_LIST
+        0: |dd00dd|AST_ASSIGN|
+            var: |00dddd|AST_PROP|
+                expr: AST_VAR
+                    name: |00dddd|"this"|
+                prop: |00dddd|"name"|
+            expr: AST_VAR
+                name: |ff0000|"name"|
+    returnType: null
+</example>
+</div>
+</slide>

slides/internals/scanner-rules.xml

@@ -0,0 +1,30 @@
+<slide>
+<title>Scanner Rules</title>
+
+<list>
+    <bullet>Gives Meaning to Tokens</bullet>
+    <bullet>Constructs AST through Rules:
+<example inline="1">class_declaration_statement:
+        class_modifiers T_CLASS |dd00dd|{ $&amp;lt;num>$ = CG(zend_lineno); }|
+        T_STRING extends_from implements_list backup_doc_comment '{' class_statement_list '}'
+            { $$ = *zend_ast_create_decl*(ZEND_AST_CLASS, $1, $&amp;lt;num>3, $7, *zend_ast_get_str*($4), $5, $6, $9, NULL); }
+    |
+…
+;
+</example>
+    <example inline="1">
+  case 167:
+#line 493 "/home/derick/dev/php/php-src.git/Zend/zend_language_parser.y"
+    |dd00dd|{ (yyval.num) = CG(zend_lineno); }|
+    break;
+
+  case 168:
+#line 495 "/home/derick/dev/php/php-src.git/Zend/zend_language_parser.y"
+    { (yyval.ast) = *zend_ast_create_decl*(ZEND_AST_CLASS, (yyvsp[(1) - (10)].num), (yyvsp[(3) - (10)].num), (yyvsp[(7) - (10)].str), *zend_ast_get_str*((yyvsp[(4) - (10)].ast)), (yyvsp[(5) - (10)].ast), (yyvsp[(6) - (10)].ast), (yyvsp[(9) - (10)].ast), NULL); }
+    break;
+    </example>
+
+</bullet>
+</list>
+</slide>
+

slides/internals/scanner.xml

@@ -0,0 +1,31 @@
+<slide>
+<title>Scanner Rules</title>
+
+<example inline="1">top_statement:
+        statement                           { $$ = $1; }
+    |   function_declaration_statement      { $$ = $1; }
+    |   |0000dd|class_declaration_statement|         { $$ = $1; }
+    |   trait_declaration_statement         { $$ = $1; }
+…
+;
+
+|0000dd|class_declaration_statement|:
+        |dd00dd|class_modifiers| T_CLASS { $&amp;lt;num>$ = CG(zend_lineno); }
+        T_STRING extends_from implements_list backup_doc_comment '{' class_statement_list '}'
+            { $$ = *zend_ast_create_decl*(ZEND_AST_CLASS, $1, $&amp;lt;num>3, $7, *zend_ast_get_str*($4), $5, $6, $9, NULL); }
+    |   T_CLASS { $&amp;lt;num>$ = CG(zend_lineno); }
+        T_STRING extends_from implements_list backup_doc_comment '{' class_statement_list '}'
+            { $$ = *zend_ast_create_decl*(ZEND_AST_CLASS, 0, $&amp;lt;num>2, $6, *zend_ast_get_str*($3), $4, $5, $8, NULL); }
+;
+
+|dd00dd|class_modifiers|:
+        |00dddd|class_modifier|                  { $$ = $1; }
+    |   |dd00dd|class_modifiers| |00dddd|class_modifier|  { $$ = *zend_add_class_modifier*($1, $2); }
+;
+
+|00dddd|class_modifier|:
+        T_ABSTRACT      { $$ = ZEND_ACC_EXPLICIT_ABSTRACT_CLASS; }
+    |   T_FINAL         { $$ = ZEND_ACC_FINAL; }
+;
+</example>
+</slide>

slides/internals/stages.xml

@@ -0,0 +1,54 @@
+<slide>
+<title style="center">Stages</title>
+
+<break lines="2"/>
+<div effect="fade-out">
+	<div class="center">
+	<blurb>Parse Script</blurb>
+	<blurb>Create Logical Representation</blurb>
+	<blurb>Create Executable Code</blurb>
+	<blurb>Execute Bytecode</blurb>
+	</div>
+</div>
+
+<div effect="fade-in-out">
+	<div class="center">
+	<blurb>*Parse Script*</blurb>
+	<blurb class="small">Convert code into Tokens</blurb><br/>
+	<blurb>Create Logical Representation</blurb>
+	<blurb>Create Executable Code</blurb>
+	<blurb>Execute Bytecode</blurb>
+	</div>
+</div>
+
+<div effect="fade-in-out">
+	<div class="center">
+	<blurb>Parse Script</blurb><br/>
+	<blurb>*Create Logical Representation*</blurb>
+	<blurb class="small">Convert Tokens into Abstract Syntax Tree (AST)</blurb><br/>
+	<blurb>Create Executable Code</blurb>
+	<blurb>Execute Bytecode</blurb>
+	</div>
+</div>
+
+<div effect="fade-in-out">
+	<div class="center">
+	<blurb>Parse Script</blurb>
+	<blurb>Create Logical Representation</blurb><br/>
+	<blurb>*Create Executable Code*</blurb>
+	<blurb class="small">Convert AST into Opcodes (Bytecode)</blurb><br/>
+	<blurb>Execute Bytecode</blurb>
+	</div>
+</div>
+
+<div effect="fade-in">
+	<div class="center">
+	<blurb>Parse Script</blurb>
+	<blurb>Create Logical Representation</blurb>
+	<blurb>Create Executable Code</blurb><br/>
+	<blurb>*Execute Bytecode*</blurb>
+	<blurb class="small">Run the Opcodes with the Zend Engine</blurb><br/>
+	</div>
+</div>
+
+</slide>

slides/internals/title-agenda.xml

@@ -0,0 +1,9 @@
+<slide>
+<title>Agenda</title>
+
+<list>
+	<bullet>Stages</bullet>
+	<bullet>Conversion Stages</bullet>
+	<bullet>Conclusion</bullet>
+</list>
+</slide>

slides/internals/title-parsing.xml

@@ -0,0 +1,4 @@
+<slide style="title">
+<title>Parsing</title>
+<image align="center" filename="tokens.jpg" attr="$1LENCE D00600D at English Wikipedia"/>
+</slide>

slides/internals/title-stages.xml

@@ -0,0 +1,4 @@
+<slide style="title">
+<title>Stages</title>
+<image align="center" filename="stages.jpg" attr=""/>
+</slide>

slides/mongodb/me.xml

@@ -6,7 +6,7 @@
 
 	<blurb>Derick Rethans</blurb>
 	<list>
-		<bullet>I'm *Dutch/British* living in London</bullet>
+		<bullet>I'm ---Dutch/British--- European, living in London</bullet>
 		<bullet>One of the PHP/HHVM *MongoDB* driver maintainers</bullet>
 		<bullet>Author of the PHP debugger tool *Xdebug*, PHP's Date/Time/Timezone support, and a bunch of other PHP extensions</bullet>
 		<bullet>I ♥🌍 maps, I ♥🍺 beer, I ♥🥃  whisky</bullet>

templates/default/div.ezt

@@ -1,7 +1,7 @@
 {use $node, $pres}
 {var $class = get_attribute( $node, 'class' )}
 {var $effect = get_attribute( $node, 'effect' )}
-<div{if $effect} class='effect-{$effect}'{/if}{if $class} class="{$class}"{/if}>
+<div{if $effect || $class} class='{/if}{if $effect}effect-{$effect}{/if} {if $class}{literal} {/literal}{$class}{/if} {if $effect || $class}'{/if}>
 {foreach $node->childNodes as $child}
 	{if is_set( $child->tagName )}
 		{include $child->tagName . '.ezt' send $child as $node, $pres}