r252777 - [TLS] move setting tls_guard in tls_init.

[Manman Ren via cfe-commits]

Author: mren
Date: Wed Nov 11 13:19:26 2015
New Revision: 252777

URL: http://llvm.org/viewvc/llvm-project?rev=252777&view=rev
Log:
[TLS] move setting tls_guard in tls_init.

We used to emit the store prior to branch in the entry block. To make it more
efficient, this commit moves it to the init block. We still mark as initialized
before initializing anything else.

Modified:
    cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
    cfe/trunk/test/CodeGenCXX/cxx11-thread-local.cpp
    cfe/trunk/test/OpenMP/threadprivate_codegen.cpp

Modified: cfe/trunk/lib/CodeGen/CGDeclCXX.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDeclCXX.cpp?rev=252777&r1=252776&r2=252777&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDeclCXX.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDeclCXX.cpp Wed Nov 11 13:19:26 2015
@@ -518,14 +518,14 @@ CodeGenFunction::GenerateCXXGlobalInitFu
       llvm::Value *GuardVal = Builder.CreateLoad(Guard);
       llvm::Value *Uninit = Builder.CreateIsNull(GuardVal,
                                                  "guard.uninitialized");
-      // Mark as initialized before initializing anything else. If the
-      // initializers use previously-initialized thread_local vars, that's
-      // probably supposed to be OK, but the standard doesn't say.
-      Builder.CreateStore(llvm::ConstantInt::get(GuardVal->getType(),1), Guard);
       llvm::BasicBlock *InitBlock = createBasicBlock("init");
       ExitBlock = createBasicBlock("exit");
       Builder.CreateCondBr(Uninit, InitBlock, ExitBlock);
       EmitBlock(InitBlock);
+      // Mark as initialized before initializing anything else. If the
+      // initializers use previously-initialized thread_local vars, that's
+      // probably supposed to be OK, but the standard doesn't say.
+      Builder.CreateStore(llvm::ConstantInt::get(GuardVal->getType(),1), Guard);
     }
 
     RunCleanupsScope Scope(*this);

Modified: cfe/trunk/test/CodeGenCXX/cxx11-thread-local.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/cxx11-thread-local.cpp?rev=252777&r1=252776&r2=252777&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/cxx11-thread-local.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/cxx11-thread-local.cpp Wed Nov 11 13:19:26 2015
@@ -173,9 +173,9 @@ void set_anon_i() {
 // CHECK: define {{.*}}@__tls_init()
 // CHECK: load i8, i8* @__tls_guard
 // CHECK: %[[NEED_TLS_INIT:.*]] = icmp eq i8 %{{.*}}, 0
-// CHECK: store i8 1, i8* @__tls_guard
 // CHECK: br i1 %[[NEED_TLS_INIT]],
 // init:
+// CHECK: store i8 1, i8* @__tls_guard
 // CHECK: call void @[[A_INIT]]()
 // CHECK: call void @[[D_INIT]]()
 // CHECK: call void @[[U_M_INIT]]()

Modified: cfe/trunk/test/OpenMP/threadprivate_codegen.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/OpenMP/threadprivate_codegen.cpp?rev=252777&r1=252776&r2=252777&view=diff
==============================================================================
--- cfe/trunk/test/OpenMP/threadprivate_codegen.cpp (original)
+++ cfe/trunk/test/OpenMP/threadprivate_codegen.cpp Wed Nov 11 13:19:26 2015
@@ -939,9 +939,9 @@ int foobar() {
 // CHECK-TLS:      define internal void @__tls_init()
 // CHECK-TLS:      [[GRD:%.*]] = load i8, i8* @__tls_guard
 // CHECK-TLS-NEXT: [[IS_INIT:%.*]] = icmp eq i8 [[GRD]], 0
-// CHECK-TLS-NEXT: store i8 1, i8* @__tls_guard
 // CHECK-TLS-NEXT: br i1 [[IS_INIT]], label %[[INIT_LABEL:[^,]+]], label %[[DONE_LABEL:[^,]+]]{{.*}}
 // CHECK-TLS:      [[INIT_LABEL]]
+// CHECK-TLS-NEXT: store i8 1, i8* @__tls_guard
 // CHECK-TLS:      call void [[GS1_CXX_INIT]]
 // CHECK-TLS-NOT:  call void [[GS2_CXX_INIT]]
 // CHECK-TLS:      call void [[ARR_X_CXX_INIT]]