Bug 736012 - Unwind current frame on failure to enter jit code from loop header (r=bhackett)

--HG--
extra : rebase_source : 5dcfb53368a6f816b44d26cf43b564f1525d74bb

js/src/jit-test/tests/basic/testBug736012.js

@@ -0,0 +1,8 @@
+evaluate("\
+function fatty() {\
+    try { fatty(); } catch (e) {\
+        for each (foo in [1]) {}\
+    }\
+}\
+fatty();\
+");

js/src/jsinterp.cpp

@@ -463,7 +463,7 @@ js::RunScript(JSContext *cx, JSScript *script, StackFrame *fp)
         return false;
 
     if (status == mjit::Compile_Okay)
-        return mjit::JaegerShot(cx, false);
+        return mjit::JaegerStatusToSuccess(mjit::JaegerShot(cx, false));
 #endif
 
     return Interpret(cx, fp);
@@ -1744,8 +1744,9 @@ check_backedge:
         void *ncode =
             script->nativeCodeForPC(regs.fp()->isConstructing(), regs.pc);
         JS_ASSERT(ncode);
-        mjit::JaegerStatus status =
-            mjit::JaegerShotAtSafePoint(cx, ncode, true);
+        mjit::JaegerStatus status = mjit::JaegerShotAtSafePoint(cx, ncode, true);
+        if (status == mjit::Jaeger_ThrowBeforeEnter)
+            goto error;
         CHECK_PARTIAL_METHODJIT(status);
         interpReturnOK = (status == mjit::Jaeger_Returned);
         if (entryFrame != regs.fp())
@@ -2728,7 +2729,7 @@ BEGIN_CASE(JSOP_FUNCALL)
         if (status == mjit::Compile_Okay) {
             mjit::JaegerStatus status = mjit::JaegerShot(cx, true);
             CHECK_PARTIAL_METHODJIT(status);
-            interpReturnOK = (status == mjit::Jaeger_Returned);
+            interpReturnOK = mjit::JaegerStatusToSuccess(status);
             CHECK_INTERRUPT_HANDLER();
             goto jit_return;
         }

js/src/methodjit/MethodJIT.cpp

@@ -1106,7 +1106,7 @@ CheckStackAndEnterMethodJIT(JSContext *cx, StackFrame *fp, void *code, bool part
 
     Value *stackLimit = cx->stack.space().getStackLimit(cx, REPORT_ERROR);
     if (!stackLimit)
-        return Jaeger_Throwing;
+        return Jaeger_ThrowBeforeEnter;
 
     return EnterMethodJIT(cx, fp, code, stackLimit, partial);
 }

js/src/methodjit/MethodJIT.h

@@ -454,9 +454,23 @@ enum JaegerStatus
      * The trap has been reinstalled, but should not execute again when
      * resuming execution.
      */
-    Jaeger_UnfinishedAtTrap = 3
+    Jaeger_UnfinishedAtTrap = 3,
+
+    /*
+     * An exception was thrown before entering jit code, so the caller should
+     * 'goto error'.
+     */
+    Jaeger_ThrowBeforeEnter = 4
 };
 
+static inline bool
+JaegerStatusToSuccess(JaegerStatus status)
+{
+    JS_ASSERT(status != Jaeger_Unfinished);
+    JS_ASSERT(status != Jaeger_UnfinishedAtTrap);
+    return status == Jaeger_Returned;
+}
+
 /*
  * Method JIT compartment data. Currently, there is exactly one per
  * JS compartment. It would be safe for multiple JS compartments to