# HG changeset patch
# User Benjamin Bouvier <benj@benj.me>
# Date 1518454634 -3600
# Node ID cdb66b98f4bc7f6550dea2056e60715ea311425d
# Parent  d590eaeb2063c2285eead9cd431e7c66928b137d
Bug 1437499: Commonize CalledFromJitExitFrameLayout and use it for wasm too; r=jandem

MozReview-Commit-ID: LP2VUYNkQTJ

diff --git a/js/src/jit-test/tests/wasm/regress/ion-error-gc-fakeexitframe.js b/js/src/jit-test/tests/wasm/regress/ion-error-gc-fakeexitframe.js
new file mode 100644
--- /dev/null
+++ b/js/src/jit-test/tests/wasm/regress/ion-error-gc-fakeexitframe.js
@@ -0,0 +1,81 @@
+var lfLogBuffer = `
+//corefuzz-dcd-endofdata
+for (var i = 0; gczeal(4,10); g(buffer))
+  assertEq(assignParameterGetElement(42), 17);
+//corefuzz-dcd-endofdata
+//corefuzz-dcd-endofdata
+//corefuzz-dcd-endofdata
+g = newGlobal();
+g.parent = this
+g.eval("Debugger(parent).onExceptionUnwind=(function(){})")
+`;
+lfLogBuffer = lfLogBuffer.split('\n');
+
+gcPreserveCode();
+
+var letext =`(module
+  (type $type0 (func (param i32 i64)))
+  (type $type1 (func (param i32) (result i64)))
+  (type $type2 (func (result i32)))
+  (memory 1)
+  (export "store" $func0)
+  (export "load" $func1)
+  (export "assert_0" $func2)
+  (func $func0 (param $var0 i32) (param $var1 i64)
+    get_local $var0
+    get_local $var1
+    i64.store16 offset=16
+  )
+  (func $func1 (param $var0 i32) (result i64)
+    get_local $var0
+    i64.load16_s offset=16
+  )
+  (func $func2 (result i32)
+    i32.const 65519
+    i64.const -32768
+    call $func0
+    i32.const 1
+  )
+  (data (i32.const 0)
+    "\\00\\01\\02\\03\\04\\05\\06\\07\\08\t\n\\0b\\0c\\0d\\0e\\0f"
+  )
+  (data (i32.const 16)
+    "\\f0\\f1\\f2\\f3\\f4\\f5\\f6\\f7\\f8\\f9\\fa\\fb\\fc\\fd\\fe\\ff"
+  )
+)`;
+
+var binary = wasmTextToBinary(letext);
+var module = new WebAssembly.Module(binary);
+
+var lfCodeBuffer = "";
+while (true) {
+    var line = lfLogBuffer.shift();
+    if (line == null) {
+        break;
+    } else if (line == "//corefuzz-dcd-endofdata") {
+        processCode(lfCodeBuffer);
+    } else {
+        lfCodeBuffer += line + "\n";
+    }
+}
+
+if (lfCodeBuffer) processCode(lfCodeBuffer);
+
+function processCode(code) {
+    evaluate(code);
+    while (true) {
+        imports = {}
+        try {
+            instance = new WebAssembly.Instance(module, imports);
+            break;
+        } catch (exc) {}
+    }
+    for (let descriptor of WebAssembly.Module.exports(module)) {
+        switch (descriptor.kind) {
+            case "function":
+                try {
+                    print(instance.exports[descriptor.name]())
+                } catch (exc1) {}
+        }
+    }
+}
diff --git a/js/src/jit/JitFrames.cpp b/js/src/jit/JitFrames.cpp
--- a/js/src/jit/JitFrames.cpp
+++ b/js/src/jit/JitFrames.cpp
@@ -874,18 +874,17 @@ TraceThisAndArguments(JSTracer* trc, con
     if (!CalleeTokenIsFunction(layout->calleeToken()))
         return;
 
     size_t nargs = layout->numActualArgs();
     size_t nformals = 0;
 
     JSFunction* fun = CalleeTokenToFunction(layout->calleeToken());
     if (frame.type() != JitFrame_JSJitToWasm &&
-        !frame.isExitFrameLayout<LazyLinkExitFrameLayout>() &&
-        !frame.isExitFrameLayout<InterpreterStubExitFrameLayout>() &&
+        !frame.isExitFrameLayout<CalledFromJitExitFrameLayout>() &&
         !fun->nonLazyScript()->mayReadFrameArgsDirectly())
     {
         nformals = fun->nargs();
     }
 
     size_t newTargetOffset = Max(nargs, fun->nargs());
 
     Value* argv = layout->argv();
@@ -1171,26 +1170,18 @@ TraceJitExitFrame(JSTracer* trc, const J
             Value* vp = method->vp();
             TraceRootRange(trc, len, vp, "ion-dom-args");
         } else {
             TraceRoot(trc, dom->vp(), "ion-dom-args");
         }
         return;
     }
 
-    if (frame.isExitFrameLayout<LazyLinkExitFrameLayout>()) {
-        auto* layout = frame.exitFrame()->as<LazyLinkExitFrameLayout>();
-        JitFrameLayout* jsLayout = layout->jsFrame();
-        jsLayout->replaceCalleeToken(TraceCalleeToken(trc, jsLayout->calleeToken()));
-        TraceThisAndArguments(trc, frame, jsLayout);
-        return;
-    }
-
-    if (frame.isExitFrameLayout<InterpreterStubExitFrameLayout>()) {
-        auto* layout = frame.exitFrame()->as<InterpreterStubExitFrameLayout>();
+    if (frame.isExitFrameLayout<CalledFromJitExitFrameLayout>()) {
+        auto* layout = frame.exitFrame()->as<CalledFromJitExitFrameLayout>();
         JitFrameLayout* jsLayout = layout->jsFrame();
         jsLayout->replaceCalleeToken(TraceCalleeToken(trc, jsLayout->calleeToken()));
         TraceThisAndArguments(trc, frame, jsLayout);
         return;
     }
 
     if (frame.isBareExit()) {
         // Nothing to trace. Fake exit frame pushed for VM functions with
diff --git a/js/src/jit/JitFrames.h b/js/src/jit/JitFrames.h
--- a/js/src/jit/JitFrames.h
+++ b/js/src/jit/JitFrames.h
@@ -821,75 +821,69 @@ ExitFrameLayout::as<IonDOMExitFrameLayou
 struct IonDOMMethodExitFrameLayoutTraits {
     static const size_t offsetOfArgcFromArgv =
         offsetof(IonDOMMethodExitFrameLayout, argc_) -
         offsetof(IonDOMMethodExitFrameLayout, argv_);
 };
 
 // Cannot inherit implementation since we need to extend the top of
 // ExitFrameLayout.
-class LazyLinkExitFrameLayout
+class CalledFromJitExitFrameLayout
 {
   protected: // silence clang warning about unused private fields
     ExitFooterFrame footer_;
     JitFrameLayout exit_;
 
   public:
-    static ExitFrameType Type() { return ExitFrameType::LazyLink; }
-
     static inline size_t Size() {
-        return sizeof(LazyLinkExitFrameLayout);
-    }
-
-    inline JitFrameLayout* jsFrame() {
-        return &exit_;
-    }
-    static size_t offsetOfExitFrame() {
-        return offsetof(LazyLinkExitFrameLayout, exit_);
-    }
-};
-
-template <>
-inline LazyLinkExitFrameLayout*
-ExitFrameLayout::as<LazyLinkExitFrameLayout>()
-{
-    MOZ_ASSERT(is<LazyLinkExitFrameLayout>());
-    uint8_t* sp = reinterpret_cast<uint8_t*>(this);
-    sp -= LazyLinkExitFrameLayout::offsetOfExitFrame();
-    return reinterpret_cast<LazyLinkExitFrameLayout*>(sp);
-}
-
-class InterpreterStubExitFrameLayout
-{
-  protected: // silence clang warning about unused private fields
-    ExitFooterFrame footer_;
-    JitFrameLayout exit_;
-
-  public:
-    static ExitFrameType Type() { return ExitFrameType::InterpreterStub; }
-
-    static inline size_t Size() {
-        return sizeof(InterpreterStubExitFrameLayout);
+        return sizeof(CalledFromJitExitFrameLayout);
     }
     inline JitFrameLayout* jsFrame() {
         return &exit_;
     }
     static size_t offsetOfExitFrame() {
-        return offsetof(InterpreterStubExitFrameLayout, exit_);
+        return offsetof(CalledFromJitExitFrameLayout, exit_);
     }
 };
 
-template <>
-inline InterpreterStubExitFrameLayout*
-ExitFrameLayout::as<InterpreterStubExitFrameLayout>()
+class LazyLinkExitFrameLayout : public CalledFromJitExitFrameLayout
+{
+  public:
+    static ExitFrameType Type() { return ExitFrameType::LazyLink; }
+};
+
+class InterpreterStubExitFrameLayout : public CalledFromJitExitFrameLayout
+{
+  public:
+    static ExitFrameType Type() { return ExitFrameType::InterpreterStub; }
+};
+
+class WasmExitFrameLayout : CalledFromJitExitFrameLayout
 {
-    MOZ_ASSERT(is<InterpreterStubExitFrameLayout>());
+  public:
+    static ExitFrameType Type() { return ExitFrameType::WasmJitEntry; }
+};
+
+template<>
+inline bool
+ExitFrameLayout::is<CalledFromJitExitFrameLayout>()
+{
+    return is<InterpreterStubExitFrameLayout>() ||
+           is<LazyLinkExitFrameLayout>() ||
+           is<WasmExitFrameLayout>();
+}
+
+template <>
+inline CalledFromJitExitFrameLayout*
+ExitFrameLayout::as<CalledFromJitExitFrameLayout>()
+{
+    MOZ_ASSERT(is<CalledFromJitExitFrameLayout>());
     uint8_t* sp = reinterpret_cast<uint8_t*>(this);
-    sp -= InterpreterStubExitFrameLayout::offsetOfExitFrame();
-    return reinterpret_cast<InterpreterStubExitFrameLayout*>(sp);
+    sp -= CalledFromJitExitFrameLayout::offsetOfExitFrame();
+    return reinterpret_cast<CalledFromJitExitFrameLayout*>(sp);
 }
 
 class ICStub;
 
 class JitStubFrameLayout : public CommonFrameLayout
 {
     // Info on the stack
     //