From 05b4af7078f846aea6bc1e51fea1f38aa2a41803 Mon Sep 17 00:00:00 2001
From: Owen Anderson <resistor@mac.com>
Date: Thu, 14 Oct 2010 17:26:06 +0000
Subject: [PATCH] Apparently MSVC doesn't support thread-safe static local
 initialization.  Roll our own solution instead.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116489 91177308-0d34-0410-b5e6-96231b3b80d8
---
 include/llvm/PassSupport.h | 46 +++++++++++++++++++++++-----------------------
 1 file changed, 23 insertions(+), 23 deletions(-)

diff --git a/include/llvm/PassSupport.h b/include/llvm/PassSupport.h
index e0e4e8a6133..a81af56cea9 100644
--- a/include/llvm/PassSupport.h
+++ b/include/llvm/PassSupport.h
@@ -24,7 +24,7 @@
 #include "Pass.h"
 #include "llvm/PassRegistry.h"
 #include "llvm/InitializePasses.h"
-#include "llvm/Support/Compiler.h"
+#include "llvm/System/Atomic.h"
 #include <vector>
 
 namespace llvm {
@@ -137,10 +137,10 @@ private:
     return PI; \
   } \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
-    ATTRIBUTE_USED \
-    static void* initialized = initialize##passName##PassOnce(Registry); \
-  } \
-  static RegisterPass<passName> passName ## _info(arg, name, cfg, analysis);
+    static sys::cas_flag initialized = 0; \
+    sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
+    if (old_val == 0) initialize##passName##PassOnce(Registry); \
+  }
 
 #define INITIALIZE_PASS_BEGIN(passName, arg, name, cfg, analysis) \
   static void* initialize##passName##PassOnce(PassRegistry &Registry) {
@@ -157,10 +157,10 @@ private:
     return PI; \
   } \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
-    ATTRIBUTE_USED \
-    static void* initialized = initialize##passName##PassOnce(Registry); \
-  } \
-  static RegisterPass<passName> passName ## _info(arg, name, cfg, analysis);
+    static sys::cas_flag initialized = 0; \
+    sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
+    if (old_val == 0) initialize##passName##PassOnce(Registry); \
+  }
 
 template<typename PassName>
 Pass *callDefaultCtor() { return new PassName(); }
@@ -244,10 +244,11 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
     return AI; \
   } \
   void llvm::initialize##agName##AnalysisGroup(PassRegistry &Registry) { \
-    ATTRIBUTE_USED static void* initialized = \
-      initialize##agName##AnalysisGroupOnce(Registry); \
-  } \
-  static RegisterAnalysisGroup<agName> agName##_info (name);
+    static sys::cas_flag initialized = 0; \
+    sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
+    if (old_val == 0) initialize##agName##AnalysisGroupOnce(Registry); \
+  }
+
 
 #define INITIALIZE_AG_PASS(passName, agName, arg, name, cfg, analysis, def) \
   static void* initialize##passName##PassOnce(PassRegistry &Registry) { \
@@ -260,11 +261,11 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
     return AI; \
   } \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
-    ATTRIBUTE_USED \
-    static void* initialized = initialize##passName##PassOnce(Registry); \
-  } \
-  static RegisterPass<passName> passName ## _info(arg, name, cfg, analysis); \
-  static RegisterAnalysisGroup<agName, def> passName ## _ag(passName ## _info);
+    static sys::cas_flag initialized = 0; \
+    sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
+    if (old_val == 0) initialize##passName##PassOnce(Registry); \
+  }
+
 
 #define INITIALIZE_AG_PASS_BEGIN(passName, agName, arg, n, cfg, analysis, def) \
   static void* initialize##passName##PassOnce(PassRegistry &Registry) {
@@ -279,11 +280,10 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
     return AI; \
   } \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) { \
-    ATTRIBUTE_USED \
-    static void* initialized = initialize##passName##PassOnce(Registry); \
-  } \
-  static RegisterPass<passName> passName ## _info(arg, n, cfg, analysis); \
-  static RegisterAnalysisGroup<agName, def> passName ## _ag(passName ## _info);
+    static sys::cas_flag initialized = 0; \
+    sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0); \
+    if (old_val == 0) initialize##passName##PassOnce(Registry); \
+  }
 
 //===---------------------------------------------------------------------------
 /// PassRegistrationListener class - This class is meant to be derived from by
-- 
2.11.0