--- a/js/src/Makefile.in
+++ b/js/src/Makefile.in
@@ -315,30 +315,33 @@ ifeq (mips, $(findstring mips,$(TARGET_C
 CPPSRCS +=	TrampolineMIPS.cpp
 endif
 #
 # END enclude sources for the method JIT
 #############################################
 
 endif
 
-# For architectures without YARR JIT, PCRE is faster than the YARR
-# interpreter (bug 684559).
-
 ifeq (,$(filter arm% sparc %86 x86_64 mips%,$(TARGET_CPU)))
 
-VPATH +=        $(srcdir)/yarr/pcre \
+VPATH +=	$(srcdir)/assembler \
+		$(srcdir)/assembler/wtf \
+		$(srcdir)/assembler/jit \
+		$(srcdir)/yarr \
 		$(NULL)
 
-CPPSRCS += \
-                pcre_compile.cpp \
-                pcre_exec.cpp \
-                pcre_tables.cpp \
-                pcre_xclass.cpp \
-                pcre_ucp_searchfuncs.cpp \
+CPPSRCS +=	ExecutableAllocator.cpp \
+		ExecutableAllocatorPosix.cpp \
+		OSAllocatorOS2.cpp \
+		OSAllocatorPosix.cpp \
+		OSAllocatorWin.cpp \
+		PageBlock.cpp \
+		YarrInterpreter.cpp \
+		YarrPattern.cpp \
+		YarrSyntaxChecker.cpp \
 		$(NULL)
 else
 
 ###############################################
 # BEGIN include sources for the Nitro assembler
 #
 
 ENABLE_YARR_JIT = 1

--- a/js/src/assembler/jit/ExecutableAllocator.h
+++ b/js/src/assembler/jit/ExecutableAllocator.h
@@ -462,18 +462,16 @@ public:
             : "r" (code), "r" (reinterpret_cast<char*>(code) + size)
             : "r0", "r1", "r2");
     }
 #elif WTF_CPU_SPARC
     static void cacheFlush(void* code, size_t size)
     {
         sync_instruction_memory((caddr_t)code, size);
     }
-#else
-    #error "The cacheFlush support is missing on this platform."
 #endif
 
 private:
 
 #if ENABLE_ASSEMBLER_WX_EXCLUSIVE
     static void reprotectRegion(void*, size_t, ProtectionSetting);
 #endif
 

--- a/js/src/vm/RegExpObject-inl.h
+++ b/js/src/vm/RegExpObject-inl.h
@@ -132,26 +132,28 @@ RegExpObject::setMultiline(bool enabled)
 }
 
 inline void
 RegExpObject::setSticky(bool enabled)
 {
     setSlot(STICKY_FLAG_SLOT, BooleanValue(enabled));
 }
 
+#if ENABLE_YARR_JIT
 /* This function should be deleted once bad Android platforms phase out. See bug 604774. */
 inline bool
 detail::RegExpCode::isJITRuntimeEnabled(JSContext *cx)
 {
 #if defined(ANDROID) && defined(JS_METHODJIT)
     return cx->methodJitEnabled;
 #else
     return true;
 #endif
 }
+#endif
 
 inline bool
 RegExpToShared(JSContext *cx, JSObject &obj, RegExpGuard *g)
 {
     JS_ASSERT(ObjectClassIs(obj, ESClass_RegExp, cx));
     if (obj.isRegExp())
         return obj.asRegExp().getShared(cx, g);
     return Proxy::regexp_toShared(cx, &obj, g);

--- a/js/src/vm/RegExpObject.cpp
+++ b/js/src/vm/RegExpObject.cpp
@@ -163,17 +163,16 @@ MatchPairs::checkAgainst(size_t inputLen
             continue;
         JS_ASSERT(size_t(p.limit) <= inputLength);
     }
 #endif
 }
 
 /* detail::RegExpCode */
 
-#if ENABLE_YARR_JIT
 void
 RegExpCode::reportYarrError(JSContext *cx, TokenStream *ts, ErrorCode error)
 {
     switch (error) {
       case JSC::Yarr::NoError:
         JS_NOT_REACHED("Called reportYarrError with value for no error");
         return;
 #define COMPILE_EMSG(__code, __msg)                                                              \
@@ -195,73 +194,36 @@ RegExpCode::reportYarrError(JSContext *c
       COMPILE_EMSG(QuantifierTooLarge, JSMSG_BAD_QUANTIFIER);
       COMPILE_EMSG(EscapeUnterminated, JSMSG_TRAILING_SLASH);
 #undef COMPILE_EMSG
       default:
         JS_NOT_REACHED("Unknown Yarr error code");
     }
 }
 
-#else /* !ENABLE_YARR_JIT */
-
-void
-RegExpCode::reportPCREError(JSContext *cx, int error)
-{
-#define REPORT(msg_) \
-    JS_ReportErrorFlagsAndNumberUC(cx, JSREPORT_ERROR, js_GetErrorMessage, NULL, msg_); \
-    return
-    switch (error) {
-      case -2: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      case 0: JS_NOT_REACHED("Precondition violation: an error must have occurred.");
-      case 1: REPORT(JSMSG_TRAILING_SLASH);
-      case 2: REPORT(JSMSG_TRAILING_SLASH);
-      case 3: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      case 4: REPORT(JSMSG_BAD_QUANTIFIER);
-      case 5: REPORT(JSMSG_BAD_QUANTIFIER);
-      case 6: REPORT(JSMSG_BAD_CLASS_RANGE);
-      case 7: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      case 8: REPORT(JSMSG_BAD_CLASS_RANGE);
-      case 9: REPORT(JSMSG_BAD_QUANTIFIER);
-      case 10: REPORT(JSMSG_UNMATCHED_RIGHT_PAREN);
-      case 11: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      case 12: REPORT(JSMSG_UNMATCHED_RIGHT_PAREN);
-      case 13: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      case 14: REPORT(JSMSG_MISSING_PAREN);
-      case 15: REPORT(JSMSG_BAD_BACKREF);
-      case 16: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      case 17: REPORT(JSMSG_REGEXP_TOO_COMPLEX);
-      default:
-        JS_NOT_REACHED("Precondition violation: unknown PCRE error code.");
-    }
-#undef REPORT
-}
-
-#endif /* ENABLE_YARR_JIT */
-
 bool
 RegExpCode::compile(JSContext *cx, JSLinearString &pattern, unsigned *parenCount, RegExpFlag flags)
 {
-#if ENABLE_YARR_JIT
     /* Parse the pattern. */
     ErrorCode yarrError;
     YarrPattern yarrPattern(pattern, bool(flags & IgnoreCaseFlag), bool(flags & MultilineFlag),
                             &yarrError);
     if (yarrError) {
         reportYarrError(cx, NULL, yarrError);
         return false;
     }
     *parenCount = yarrPattern.m_numSubpatterns;
 
     /*
      * The YARR JIT compiler attempts to compile the parsed pattern. If
      * it cannot, it informs us via |codeBlock.isFallBack()|, in which
      * case we have to bytecode compile it.
      */
 
-#ifdef JS_METHODJIT
+#if ENABLE_YARR_JIT && defined(JS_METHODJIT)
     if (isJITRuntimeEnabled(cx) && !yarrPattern.m_containsBackreferences) {
         JSC::ExecutableAllocator *execAlloc = cx->runtime->getExecutableAllocator(cx);
         if (!execAlloc) {
             js_ReportOutOfMemory(cx);
             return false;
         }
 
         JSGlobalData globalData(execAlloc);
@@ -272,58 +234,41 @@ RegExpCode::compile(JSContext *cx, JSLin
 #endif
 
     WTF::BumpPointerAllocator *bumpAlloc = cx->runtime->getBumpPointerAllocator(cx);
     if (!bumpAlloc) {
         js_ReportOutOfMemory(cx);
         return false;
     }
 
+#if ENABLE_YARR_JIT
     codeBlock.setFallBack(true);
+#endif
     byteCode = byteCompile(yarrPattern, bumpAlloc).get();
     return true;
-#else /* !defined(ENABLE_YARR_JIT) */
-    int error = 0;
-    compiled = jsRegExpCompile(pattern.chars(), pattern.length(),
-                  ignoreCase() ? JSRegExpIgnoreCase : JSRegExpDoNotIgnoreCase,
-                  multiline() ? JSRegExpMultiline : JSRegExpSingleLine,
-                  parenCount, &error);
-    if (error) {
-        reportPCREError(cx, error);
-        return false;
-    }
-    return true;
-#endif
 }
 
 RegExpRunStatus
 RegExpCode::execute(JSContext *cx, const jschar *chars, size_t length, size_t start,
                     int *output, size_t outputCount)
 {
     int result;
 #if ENABLE_YARR_JIT
     (void) cx; /* Unused. */
     if (codeBlock.isFallBack())
         result = JSC::Yarr::interpret(byteCode, chars, start, length, output);
     else
         result = JSC::Yarr::execute(codeBlock, chars, start, length, output);
 #else
-    result = jsRegExpExecute(cx, compiled, chars, length, start, output, outputCount);
+    result = JSC::Yarr::interpret(byteCode, chars, start, length, output);
 #endif
 
     if (result == -1)
         return RegExpRunStatus_Success_NotFound;
 
-#if !ENABLE_YARR_JIT
-    if (result < 0) {
-        reportPCREError(cx, result);
-        return RegExpRunStatus_Error;
-    }
-#endif
-
     JS_ASSERT(result >= 0);
     return RegExpRunStatus_Success;
 }
 
 /* RegExpObject */
 
 static void
 regexp_trace(JSTracer *trc, JSObject *obj)

--- a/js/src/vm/RegExpObject.h
+++ b/js/src/vm/RegExpObject.h
@@ -47,20 +47,18 @@
 #include "jscntxt.h"
 #include "jsobj.h"
 
 #include "js/TemplateLib.h"
 
 #include "yarr/Yarr.h"
 #if ENABLE_YARR_JIT
 #include "yarr/YarrJIT.h"
+#endif
 #include "yarr/YarrSyntaxChecker.h"
-#else
-#include "yarr/pcre/pcre.h"
-#endif
 
 /*
  * JavaScript Regular Expressions
  *
  * There are several engine concepts associated with a single logical regexp:
  *
  *   RegExpObject - The JS-visible object whose .[[Class]] equals "RegExp"
  *
@@ -108,78 +106,61 @@ class RegExpObjectBuilder
 
 JSObject *
 CloneRegExpObject(JSContext *cx, JSObject *obj, JSObject *proto);
 
 namespace detail {
 
 class RegExpCode
 {
-#if ENABLE_YARR_JIT
     typedef JSC::Yarr::BytecodePattern BytecodePattern;
     typedef JSC::Yarr::ErrorCode ErrorCode;
+    typedef JSC::Yarr::YarrPattern YarrPattern;
+#if ENABLE_YARR_JIT
     typedef JSC::Yarr::JSGlobalData JSGlobalData;
     typedef JSC::Yarr::YarrCodeBlock YarrCodeBlock;
-    typedef JSC::Yarr::YarrPattern YarrPattern;
 
     /* Note: Native code is valid only if |codeBlock.isFallBack() == false|. */
     YarrCodeBlock   codeBlock;
+#endif
     BytecodePattern *byteCode;
-#else
-    JSRegExp        *compiled;
-#endif
 
   public:
     RegExpCode()
       :
 #if ENABLE_YARR_JIT
         codeBlock(),
+#endif
         byteCode(NULL)
-#else
-        compiled(NULL)
-#endif
     { }
 
     ~RegExpCode() {
 #if ENABLE_YARR_JIT
         codeBlock.release();
+#endif
         if (byteCode)
             Foreground::delete_<BytecodePattern>(byteCode);
-#else
-        if (compiled)
-            jsRegExpFree(compiled);
-#endif
     }
 
     static bool checkSyntax(JSContext *cx, TokenStream *tokenStream, JSLinearString *source) {
-#if ENABLE_YARR_JIT
         ErrorCode error = JSC::Yarr::checkSyntax(*source);
         if (error == JSC::Yarr::NoError)
             return true;
 
         reportYarrError(cx, tokenStream, error);
         return false;
-#else
-# error "Syntax checking not implemented for !ENABLE_YARR_JIT"
-#endif
     }
 
 #if ENABLE_YARR_JIT
     static inline bool isJITRuntimeEnabled(JSContext *cx);
+#endif
     static void reportYarrError(JSContext *cx, TokenStream *ts, JSC::Yarr::ErrorCode error);
-#else
-    static void reportPCREError(JSContext *cx, int error);
-#endif
 
     static size_t getOutputSize(size_t pairCount) {
-#if ENABLE_YARR_JIT
         return pairCount * 2;
-#else
-        return pairCount * 3; /* Should be x2, but PCRE has... needs. */
-#endif
     }
 
     bool compile(JSContext *cx, JSLinearString &pattern, unsigned *parenCount, RegExpFlag flags);
 
 
     RegExpRunStatus
     execute(JSContext *cx, const jschar *chars, size_t length, size_t start,
             int *output, size_t outputCount);

--- a/js/src/yarr/wtfbridge.h
+++ b/js/src/yarr/wtfbridge.h
@@ -44,19 +44,17 @@
  * WTF compatibility layer. This file provides various type and data
  * definitions for use by Yarr.
  */
 
 #include "jsstr.h"
 #include "jsprvtd.h"
 #include "vm/String.h"
 #include "assembler/wtf/Platform.h"
-#if ENABLE_YARR_JIT
 #include "assembler/jit/ExecutableAllocator.h"
-#endif
 
 namespace JSC { namespace Yarr {
 
 /*
  * Basic type definitions.
  */
 
 typedef jschar UChar;