Minimize uses of lazy initialization by adding explicit initialization functions.

src/platform-posix.cc

Index: src/platform-posix.cc
diff --git a/src/platform-posix.cc b/src/platform-posix.cc
index 59066ea39ee117c36234507bc0a35315dbdfed9c..66316594c8ce3fdfe90cc4fd296f08325b653eb5 100644
--- a/src/platform-posix.cc
+++ b/src/platform-posix.cc
@@ -147,15 +147,6 @@ UNARY_MATH_FUNCTION(sqrt, CreateSqrtFunction())
 #undef MATH_FUNCTION
 
 
-void MathSetup() {
-  init_fast_sin_function();
-  init_fast_cos_function();
-  init_fast_tan_function();
-  init_fast_log_function();
-  init_fast_sqrt_function();
-}
-
-
 double OS::nan_value() {
   // NAN from math.h is defined in C99 and not in POSIX.
   return NAN;
@@ -313,20 +304,11 @@ int OS::VSNPrintF(Vector<char> str,
 
 #if defined(V8_TARGET_ARCH_IA32)
 static OS::MemCopyFunction memcopy_function = NULL;
-static LazyMutex memcopy_function_mutex = LAZY_MUTEX_INITIALIZER;
 // Defined in codegen-ia32.cc.
 OS::MemCopyFunction CreateMemCopyFunction();
 
 // Copy memory area to disjoint memory area.
 void OS::MemCopy(void* dest, const void* src, size_t size) {
-  if (memcopy_function == NULL) {
-    ScopedLock lock(memcopy_function_mutex.Pointer());
-    if (memcopy_function == NULL) {
-      OS::MemCopyFunction temp = CreateMemCopyFunction();
-      MemoryBarrier();
-      memcopy_function = temp;
-    }
-  }
   // Note: here we rely on dependent reads being ordered. This is true
   // on all architectures we currently support.
   (*memcopy_function)(dest, src, size);
@@ -336,6 +318,18 @@ void OS::MemCopy(void* dest, const void* src, size_t size) {
 }
 #endif  // V8_TARGET_ARCH_IA32
 
+
+void POSIXPostSetUp() {
+#if defined(V8_TARGET_ARCH_IA32)
+  memcopy_function = CreateMemCopyFunction();
+#endif
+  init_fast_sin_function();
+  init_fast_cos_function();
+  init_fast_tan_function();
+  init_fast_log_function();
+  init_fast_sqrt_function();
+}
+
 // ----------------------------------------------------------------------------
 // POSIX string support.
 //