Inline simple printers (easier inline testing)

- Inlines simple constant print functions (makes it easier to test
inlining side effects in a simple manner)
- This also confirms that FPushObjMethodD inlining is working as expected

hphp/runtime/vm/jit/irtranslator.cpp

@@ -1138,6 +1138,17 @@ bool shouldIRInline(const Func* curFunc,
     return atRet();
   };
 
+  // Constants that can be printed without an InterpOne.
+  auto simplePrintConstant = [&]() -> bool {
+    switch (current) {
+    case OpFalse: case OpInt: case OpString: case OpTrue: case OpNull:
+      next();
+      return true;
+    default:
+      return false;
+    }
+  };
+
   resetCursor();
 
   ////////////
@@ -1178,7 +1189,7 @@ bool shouldIRInline(const Func* curFunc,
   }
 
   /*
-   * Continuation allocation functions that take no arguments.
+   * Continuation allocation functions.
    */
   resetCursor();
   if (current == OpCreateCont) {
@@ -1207,6 +1218,14 @@ bool shouldIRInline(const Func* curFunc,
     return accept("$this instanceof D");
   }
 
+  // E.g. String; Print; PopC; Null; RetC
+  // Useful primarily for debugging.
+  resetCursor();
+  if (simplePrintConstant() && nextIf(OpPrint) && nextIf(OpPopC) &&
+      simpleCell() && cellManipRet()) {
+    return accept("constant printer");
+  }
+
   return refuse("unknown kind of function");
 }
 

hphp/runtime/vm/jit/tracebuilder.cpp

@@ -129,8 +129,6 @@ void TraceBuilder::trackDefInlineFP(IRInstruction* inst) {
    *
    * We set m_thisIsAvailable to true on any object method, because we
    * just don't inline calls to object methods with a null $this.
-   *
-   * Static methods probably broken #2490252.
    */
   m_fpValue         = calleeFP;
   m_spValue         = calleeSP;

hphp/test/slow/ir_inlining/static_with_destructor.php

@@ -0,0 +1,15 @@
+<?php
+
+class A {
+  function __destruct() {
+    print "destructor\n";
+  }
+
+  static function printer() { print "static\n"; }
+}
+
+function main() {
+  (new A())->printer();
+}
+
+main();

hphp/test/slow/ir_inlining/static_with_destructor.php.expect

@@ -0,0 +1,2 @@
+destructor
+static