From 585bedfb6aa642e344191ecc14c794a982f4fd3f Mon Sep 17 00:00:00 2001
From: Jacob Bramley <Jacob.Bramley@arm.com>
Date: Mon, 18 May 2009 01:32:10 -0400
Subject: [PATCH] Bug 490838 -  TraceMonkey: Improve epilogue efficiency for
 ARM. r=vlad

---
 js/src/nanojit/NativeARM.cpp | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/js/src/nanojit/NativeARM.cpp b/js/src/nanojit/NativeARM.cpp
index 874b86409e52..d5faf56d3afd 100644
--- a/js/src/nanojit/NativeARM.cpp
+++ b/js/src/nanojit/NativeARM.cpp
@@ -164,10 +164,11 @@ Assembler::nFragExit(LInsp guard)
 NIns*
 Assembler::genEpilogue()
 {
-    BX(LR); // return
-
-    RegisterMask savingMask = rmask(FP) | rmask(LR);
+    // On ARMv5+, loading directly to PC correctly handles interworking.
+    // Note that we don't support anything older than ARMv5.
+    NanoAssert(AvmCore::config.arch >= 5);
 
+    RegisterMask savingMask = rmask(FP) | rmask(PC);
     if (!_thisfrag->lirbuf->explicitSavedRegs)
         for (int i = 0; i < NumSavedRegs; ++i)
             savingMask |= rmask(savedRegs[i]);