Revert "[LPM] Replace the CALL_ONCE_... macro in the legacy pass manager with the new llvm::call_once facility."

Fallback path doesn't compile. This reverts commit r271652.

llvm-svn: 271657

2 files changed, 26 insertions, 20 deletions

diff --git a/llvm/include/llvm/CodeGen/Passes.h b/llvm/include/llvm/CodeGen/Passes.h
index 7fb08496425..1e01d66a2ce 100644
--- a/llvm/include/llvm/CodeGen/Passes.h
+++ b/llvm/include/llvm/CodeGen/Passes.h
@@ -377,10 +377,8 @@ namespace llvm {
   Registry.registerPass(*PI, true);                                            \
   return PI;                                                                   \
   }                                                                            \
-  LLVM_DEFINE_ONCE_FLAG(Initialize##passName##PassFlag);                       \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) {              \
-    call_once(Initialize##passName##PassFlag, initialize##passName##PassOnce,  \
-              std::ref(Registry));                                             \
+    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce)                   \
   }
 
 /// This initializer registers TargetMachine constructor, so the pass being
diff --git a/llvm/include/llvm/PassSupport.h b/llvm/include/llvm/PassSupport.h
index 2965f463f51..f205c001f53 100644
--- a/llvm/include/llvm/PassSupport.h
+++ b/llvm/include/llvm/PassSupport.h
@@ -26,13 +26,31 @@
 #include "llvm/PassInfo.h"
 #include "llvm/PassRegistry.h"
 #include "llvm/Support/Atomic.h"
-#include "llvm/Support/Threading.h"
-#include <functional>
 
 namespace llvm {
 
 class TargetMachine;
 
+#define CALL_ONCE_INITIALIZATION(function)                                     \
+  static volatile sys::cas_flag initialized = 0;                               \
+  sys::cas_flag old_val = sys::CompareAndSwap(&initialized, 1, 0);             \
+  if (old_val == 0) {                                                          \
+    function(Registry);                                                        \
+    sys::MemoryFence();                                                        \
+    TsanIgnoreWritesBegin();                                                   \
+    TsanHappensBefore(&initialized);                                           \
+    initialized = 2;                                                           \
+    TsanIgnoreWritesEnd();                                                     \
+  } else {                                                                     \
+    sys::cas_flag tmp = initialized;                                           \
+    sys::MemoryFence();                                                        \
+    while (tmp != 2) {                                                         \
+      tmp = initialized;                                                       \
+      sys::MemoryFence();                                                      \
+    }                                                                          \
+  }                                                                            \
+  TsanHappensAfter(&initialized);
+
 #define INITIALIZE_PASS(passName, arg, name, cfg, analysis)                    \
   static void *initialize##passName##PassOnce(PassRegistry &Registry) {        \
     PassInfo *PI = new PassInfo(                                               \
@@ -41,10 +59,8 @@ class TargetMachine;
     Registry.registerPass(*PI, true);                                          \
     return PI;                                                                 \
   }                                                                            \
-  LLVM_DEFINE_ONCE_FLAG(Initialize##passName##PassFlag);                       \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) {              \
-    call_once(Initialize##passName##PassFlag, initialize##passName##PassOnce,  \
-              std::ref(Registry));                                             \
+    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce)                   \
   }
 
 #define INITIALIZE_PASS_BEGIN(passName, arg, name, cfg, analysis)              \
@@ -61,10 +77,8 @@ class TargetMachine;
   Registry.registerPass(*PI, true);                                            \
   return PI;                                                                   \
   }                                                                            \
-  LLVM_DEFINE_ONCE_FLAG(Initialize##passName##PassFlag);                       \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) {              \
-    call_once(Initialize##passName##PassFlag, initialize##passName##PassOnce,  \
-              std::ref(Registry));                                             \
+    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce)                   \
   }
 
 #define INITIALIZE_PASS_WITH_OPTIONS(PassName, Arg, Name, Cfg, Analysis)       \
@@ -152,10 +166,8 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
     Registry.registerAnalysisGroup(&agName::ID, 0, *AI, false, true);          \
     return AI;                                                                 \
   }                                                                            \
-  LLVM_DEFINE_ONCE_FLAG(Initialize##agName##AnalysisGroupFlag);                \
   void llvm::initialize##agName##AnalysisGroup(PassRegistry &Registry) {       \
-    call_once(Initialize##agName##AnalysisGroupFlag,                           \
-              initialize##agName##AnalysisGroupOnce, std::ref(Registry));      \
+    CALL_ONCE_INITIALIZATION(initialize##agName##AnalysisGroupOnce)            \
   }
 
 #define INITIALIZE_AG_PASS(passName, agName, arg, name, cfg, analysis, def)    \
@@ -172,10 +184,8 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
                                    true);                                      \
     return AI;                                                                 \
   }                                                                            \
-  LLVM_DEFINE_ONCE_FLAG(Initialize##passName##PassFlag);                       \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) {              \
-    call_once(Initialize##passName##PassFlag, initialize##passName##PassOnce,  \
-              std::ref(Registry));                                             \
+    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce)                   \
   }
 
 #define INITIALIZE_AG_PASS_BEGIN(passName, agName, arg, n, cfg, analysis, def) \
@@ -193,10 +203,8 @@ struct RegisterAnalysisGroup : public RegisterAGBase {
   Registry.registerAnalysisGroup(&agName::ID, &passName::ID, *AI, def, true);  \
   return AI;                                                                   \
   }                                                                            \
-  LLVM_DEFINE_ONCE_FLAG(Initialize##passName##PassFlag);                       \
   void llvm::initialize##passName##Pass(PassRegistry &Registry) {              \
-    call_once(Initialize##passName##PassFlag, initialize##passName##PassOnce,  \
-              std::ref(Registry));                                             \
+    CALL_ONCE_INITIALIZATION(initialize##passName##PassOnce)                   \
   }
 
 //===---------------------------------------------------------------------------