From 091969f9b851de13f72c0884541ea47adc391caf Mon Sep 17 00:00:00 2001
From: Sean Stangl <sstangl@mozilla.com>
Date: Tue, 12 Oct 2010 20:08:40 -0400
Subject: [PATCH] Eliminate ImmutableSync on x64. b=601066, r=dvander.

---
 js/src/methodjit/FrameState.cpp    | 35 +++++++++++++++++++++++++++++-
 js/src/methodjit/FrameState.h      |  4 ++++
 js/src/methodjit/ImmutableSync.cpp |  5 +++++
 js/src/methodjit/ImmutableSync.h   |  2 +-
 4 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/js/src/methodjit/FrameState.cpp b/js/src/methodjit/FrameState.cpp
index 30d2f08d75e9..831455c61ea0 100644
--- a/js/src/methodjit/FrameState.cpp
+++ b/js/src/methodjit/FrameState.cpp
@@ -47,7 +47,10 @@ using namespace js::mjit;
 JS_STATIC_ASSERT(sizeof(FrameEntry) % 8 == 0);
 
 FrameState::FrameState(JSContext *cx, JSScript *script, Assembler &masm)
-  : cx(cx), script(script), masm(masm), entries(NULL), reifier(cx, *this),
+  : cx(cx), script(script), masm(masm), entries(NULL),
+#if defined JS_NUNBOX32
+    reifier(cx, *this),
+#endif
     inTryBlock(false)
 {
 }
@@ -78,8 +81,10 @@ FrameState::init(uint32 nargs)
     if (!cursor)
         return false;
 
+#if defined JS_NUNBOX32
     if (!reifier.init(nslots))
         return false;
+#endif
 
     entries = (FrameEntry *)cursor;
     cursor += sizeof(FrameEntry) * nslots;
@@ -414,6 +419,7 @@ FrameState::assertValidRegisterState() const
 }
 #endif
 
+#if defined JS_NUNBOX32
 void
 FrameState::syncFancy(Assembler &masm, Registers avail, FrameEntry *resumeAt,
                       FrameEntry *bottom) const
@@ -427,6 +433,7 @@ FrameState::syncFancy(Assembler &masm, Registers avail, FrameEntry *resumeAt,
         reifier.sync(fe);
     }
 }
+#endif
 
 void
 FrameState::sync(Assembler &masm, Uses uses) const
@@ -489,12 +496,38 @@ FrameState::sync(Assembler &masm, Uses uses) const
             backing = fe->copyOf();
             JS_ASSERT(!backing->isConstant() && !fe->isConstant());
 
+#if defined JS_PUNBOX64
+            if ((!fe->type.synced() && backing->type.inMemory()) ||
+                (!fe->data.synced() && backing->data.inMemory())) {
+    
+                RegisterID syncReg = Registers::ValueReg;
+
+                /* Load the entire Value into syncReg. */
+                if (backing->type.synced() && backing->data.synced()) {
+                    masm.loadValue(addressOf(backing), syncReg);
+                } else if (backing->type.inMemory()) {
+                    masm.loadTypeTag(addressOf(backing), syncReg);
+                    masm.orPtr(backing->data.reg(), syncReg);
+                } else {
+                    JS_ASSERT(backing->data.inMemory());
+                    masm.loadPayload(addressOf(backing), syncReg);
+                    if (backing->isTypeKnown())
+                        masm.orPtr(ImmType(backing->getKnownType()), syncReg);
+                    else
+                        masm.orPtr(backing->type.reg(), syncReg);
+                }
+
+                masm.storeValue(syncReg, addressOf(fe));
+                continue;
+            }
+#elif defined JS_NUNBOX32
             /* Fall back to a slower sync algorithm if load required. */
             if ((!fe->type.synced() && backing->type.inMemory()) ||
                 (!fe->data.synced() && backing->data.inMemory())) {
                 syncFancy(masm, avail, fe, bottom);
                 return;
             }
+#endif
         }
 
         /* If a part still needs syncing, it is either a copy or constant. */
diff --git a/js/src/methodjit/FrameState.h b/js/src/methodjit/FrameState.h
index a858fcf228e5..6f9692380dd7 100644
--- a/js/src/methodjit/FrameState.h
+++ b/js/src/methodjit/FrameState.h
@@ -807,8 +807,10 @@ class FrameState
     inline void swapInTracker(FrameEntry *lhs, FrameEntry *rhs);
     inline uint32 localIndex(uint32 n);
     void pushCopyOf(uint32 index);
+#if defined JS_NUNBOX32
     void syncFancy(Assembler &masm, Registers avail, FrameEntry *resumeAt,
                    FrameEntry *bottom) const;
+#endif
     inline bool tryFastDoubleLoad(FrameEntry *fe, FPRegisterID fpReg, Assembler &masm) const;
     void resetInternalState();
 
@@ -882,7 +884,9 @@ class FrameState
      */
     RegisterState regstate[Assembler::TotalRegisters];
 
+#if defined JS_NUNBOX32
     mutable ImmutableSync reifier;
+#endif
 
     JSPackedBool *closedVars;
     bool eval;
diff --git a/js/src/methodjit/ImmutableSync.cpp b/js/src/methodjit/ImmutableSync.cpp
index 46260aef3029..04d26fdfb4f6 100644
--- a/js/src/methodjit/ImmutableSync.cpp
+++ b/js/src/methodjit/ImmutableSync.cpp
@@ -36,6 +36,9 @@
  * the terms of any one of the MPL, the GPL or the LGPL.
  *
  * ***** END LICENSE BLOCK ***** */
+
+#if defined JS_NUNBOX32
+
 #include "FrameEntry.h"
 #include "FrameState.h"
 #include "FrameState-inl.h"
@@ -270,3 +273,5 @@ ImmutableSync::syncNormal(FrameEntry *fe)
     }
 }
 
+#endif /* JS_NUNBOX32 */
+
diff --git a/js/src/methodjit/ImmutableSync.h b/js/src/methodjit/ImmutableSync.h
index 28234af2f6db..204dbab41891 100644
--- a/js/src/methodjit/ImmutableSync.h
+++ b/js/src/methodjit/ImmutableSync.h
@@ -37,7 +37,7 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-#if !defined jsjaeger_imm_sync_h__ && defined JS_METHODJIT
+#if !defined jsjaeger_imm_sync_h__ && defined JS_METHODJIT && defined JS_NUNBOX32
 #define jsjaeger_imm_sync_h__
 
 #include "methodjit/MachineRegs.h"