diff -r 000000000000 -r 6474c204b198 js/src/jit/IonSpewer.h
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit/IonSpewer.h	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,205 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef jit_IonSpewer_h
+#define jit_IonSpewer_h
+
+#include "mozilla/DebugOnly.h"
+
+#include <stdarg.h>
+
+#include "jit/C1Spewer.h"
+#include "jit/JSONSpewer.h"
+#include "js/RootingAPI.h"
+
+namespace js {
+namespace jit {
+
+// New channels may be added below.
+#define IONSPEW_CHANNEL_LIST(_)             \
+    /* Used to abort SSA construction */    \
+    _(Abort)                                \
+    /* Information about compiled scripts */\
+    _(Scripts)                              \
+    /* Information during MIR building */   \
+    _(Logs)                                 \
+    /* Info about failing to log script */  \
+    _(MIR)                                  \
+    /* Information during alias analysis */ \
+    _(Alias)                                \
+    /* Information during GVN */            \
+    _(GVN)                                  \
+    /* Information during Range analysis */ \
+    _(Range)                                \
+    /* Information during LICM */           \
+    _(LICM)                                 \
+    /* Information during regalloc */       \
+    _(RegAlloc)                             \
+    /* Information during inlining */       \
+    _(Inlining)                             \
+    /* Information during codegen */        \
+    _(Codegen)                              \
+    /* Information during bailouts */       \
+    _(Bailouts)                             \
+    /* Information during OSI */            \
+    _(Invalidate)                           \
+    /* Debug info about snapshots */        \
+    _(Snapshots)                            \
+    /* Generated inline cache stubs */      \
+    _(InlineCaches)                         \
+    /* Debug info about safepoints */       \
+    _(Safepoints)                           \
+    /* Debug info about Pools*/             \
+    _(Pools)                                \
+    /* Calls to js::jit::Trace() */         \
+    _(Trace)                                \
+    /* Debug info about the I$ */           \
+    _(CacheFlush)                           \
+                                            \
+    /* BASELINE COMPILER SPEW */            \
+                                            \
+    /* Aborting Script Compilation. */      \
+    _(BaselineAbort)                        \
+    /* Script Compilation. */               \
+    _(BaselineScripts)                      \
+    /* Detailed op-specific spew. */        \
+    _(BaselineOp)                           \
+    /* Inline caches. */                    \
+    _(BaselineIC)                           \
+    /* Inline cache fallbacks. */           \
+    _(BaselineICFallback)                   \
+    /* OSR from Baseline => Ion. */         \
+    _(BaselineOSR)                          \
+    /* Bailouts. */                         \
+    _(BaselineBailouts)                     \
+    /* Debug Mode On Stack Recompile . */   \
+    _(BaselineDebugModeOSR)
+
+
+enum IonSpewChannel {
+#define IONSPEW_CHANNEL(name) IonSpew_##name,
+    IONSPEW_CHANNEL_LIST(IONSPEW_CHANNEL)
+#undef IONSPEW_CHANNEL
+    IonSpew_Terminator
+};
+
+
+// The IonSpewer is only available on debug builds.
+// None of the global functions have effect on non-debug builds.
+static const int NULL_ID = -1;
+
+#ifdef DEBUG
+
+class IonSpewer
+{
+  private:
+    MIRGraph *graph;
+    JS::HandleScript function;
+    C1Spewer c1Spewer;
+    JSONSpewer jsonSpewer;
+    bool inited_;
+
+  public:
+    IonSpewer()
+      : graph(nullptr), function(NullPtr()), inited_(false)
+    { }
+
+    // File output is terminated safely upon destruction.
+    ~IonSpewer();
+
+    bool init();
+    void beginFunction(MIRGraph *graph, JS::HandleScript);
+    bool isSpewingFunction() const;
+    void spewPass(const char *pass);
+    void spewPass(const char *pass, LinearScanAllocator *ra);
+    void endFunction();
+};
+
+void IonSpewNewFunction(MIRGraph *graph, JS::HandleScript function);
+void IonSpewPass(const char *pass);
+void IonSpewPass(const char *pass, LinearScanAllocator *ra);
+void IonSpewEndFunction();
+
+void CheckLogging();
+extern FILE *IonSpewFile;
+void IonSpew(IonSpewChannel channel, const char *fmt, ...);
+void IonSpewStart(IonSpewChannel channel, const char *fmt, ...);
+void IonSpewCont(IonSpewChannel channel, const char *fmt, ...);
+void IonSpewFin(IonSpewChannel channel);
+void IonSpewHeader(IonSpewChannel channel);
+bool IonSpewEnabled(IonSpewChannel channel);
+void IonSpewVA(IonSpewChannel channel, const char *fmt, va_list ap);
+void IonSpewStartVA(IonSpewChannel channel, const char *fmt, va_list ap);
+void IonSpewContVA(IonSpewChannel channel, const char *fmt, va_list ap);
+
+void EnableChannel(IonSpewChannel channel);
+void DisableChannel(IonSpewChannel channel);
+void EnableIonDebugLogging();
+
+#else
+
+static inline void IonSpewNewFunction(MIRGraph *graph, JS::HandleScript function)
+{ }
+static inline void IonSpewPass(const char *pass)
+{ }
+static inline void IonSpewPass(const char *pass, LinearScanAllocator *ra)
+{ }
+static inline void IonSpewEndFunction()
+{ }
+
+static inline void CheckLogging()
+{ }
+static FILE *const IonSpewFile = nullptr;
+static inline void IonSpew(IonSpewChannel, const char *fmt, ...)
+{ }
+static inline void IonSpewStart(IonSpewChannel channel, const char *fmt, ...)
+{ }
+static inline void IonSpewCont(IonSpewChannel channel, const char *fmt, ...)
+{ }
+static inline void IonSpewFin(IonSpewChannel channel)
+{ }
+
+static inline void IonSpewHeader(IonSpewChannel channel)
+{ }
+static inline bool IonSpewEnabled(IonSpewChannel channel)
+{ return false; }
+static inline void IonSpewVA(IonSpewChannel channel, const char *fmt, va_list ap)
+{ }
+
+static inline void EnableChannel(IonSpewChannel)
+{ }
+static inline void DisableChannel(IonSpewChannel)
+{ }
+static inline void EnableIonDebugLogging()
+{ }
+
+#endif /* DEBUG */
+
+template <IonSpewChannel Channel>
+class AutoDisableSpew
+{
+    mozilla::DebugOnly<bool> enabled_;
+
+  public:
+    AutoDisableSpew()
+      : enabled_(IonSpewEnabled(Channel))
+    {
+        DisableChannel(Channel);
+    }
+
+    ~AutoDisableSpew()
+    {
+#ifdef DEBUG
+        if (enabled_)
+            EnableChannel(Channel);
+#endif
+    }
+};
+
+} /* ion */
+} /* js */
+
+#endif /* jit_IonSpewer_h */