From 6e8248fdad5fc59306beb286a3089fe401460826 Mon Sep 17 00:00:00 2001
From: Alexey Bataev <a.bataev@hotmail.com>
Date: Thu, 11 Jun 2015 10:53:56 +0000
Subject: [PATCH] [OPENMP] Fox for http://llvm.org/PR23663: OpenMP crash

Destroy RuntimeCleanupScope before generation of termination instruction in parallel loop precondition.

llvm-svn: 239524
---
 clang/lib/CodeGen/CGStmtOpenMP.cpp         | 50 +++++++++++-----------
 clang/test/OpenMP/parallel_for_codegen.cpp | 10 ++++-
 2 files changed, 34 insertions(+), 26 deletions(-)

diff --git a/clang/lib/CodeGen/CGStmtOpenMP.cpp b/clang/lib/CodeGen/CGStmtOpenMP.cpp
index 07fc6e966af6..895baa72a7d3 100644
--- a/clang/lib/CodeGen/CGStmtOpenMP.cpp
+++ b/clang/lib/CodeGen/CGStmtOpenMP.cpp
@@ -647,30 +647,32 @@ static void EmitPrivateLoopCounters(CodeGenFunction &CGF,
 static void emitPreCond(CodeGenFunction &CGF, const OMPLoopDirective &S,
                         const Expr *Cond, llvm::BasicBlock *TrueBlock,
                         llvm::BasicBlock *FalseBlock, uint64_t TrueCount) {
-  CodeGenFunction::OMPPrivateScope PreCondScope(CGF);
-  EmitPrivateLoopCounters(CGF, PreCondScope, S.counters());
-  const VarDecl *IVDecl =
-      cast<VarDecl>(cast<DeclRefExpr>(S.getIterationVariable())->getDecl());
-  bool IsRegistered = PreCondScope.addPrivate(IVDecl, [&]() -> llvm::Value *{
-    // Emit var without initialization.
-    auto VarEmission = CGF.EmitAutoVarAlloca(*IVDecl);
-    CGF.EmitAutoVarCleanups(VarEmission);
-    return VarEmission.getAllocatedAddress();
-  });
-  assert(IsRegistered && "counter already registered as private");
-  // Silence the warning about unused variable.
-  (void)IsRegistered;
-  (void)PreCondScope.Privatize();
-  // Initialize internal counter to 0 to calculate initial values of real
-  // counters.
-  LValue IV = CGF.EmitLValue(S.getIterationVariable());
-  CGF.EmitStoreOfScalar(
-      llvm::ConstantInt::getNullValue(
-          IV.getAddress()->getType()->getPointerElementType()),
-      CGF.EmitLValue(S.getIterationVariable()), /*isInit=*/true);
-  // Get initial values of real counters.
-  for (auto I : S.updates()) {
-    CGF.EmitIgnoredExpr(I);
+  {
+    CodeGenFunction::OMPPrivateScope PreCondScope(CGF);
+    EmitPrivateLoopCounters(CGF, PreCondScope, S.counters());
+    const VarDecl *IVDecl =
+        cast<VarDecl>(cast<DeclRefExpr>(S.getIterationVariable())->getDecl());
+    bool IsRegistered = PreCondScope.addPrivate(IVDecl, [&]() -> llvm::Value *{
+      // Emit var without initialization.
+      auto VarEmission = CGF.EmitAutoVarAlloca(*IVDecl);
+      CGF.EmitAutoVarCleanups(VarEmission);
+      return VarEmission.getAllocatedAddress();
+    });
+    assert(IsRegistered && "counter already registered as private");
+    // Silence the warning about unused variable.
+    (void)IsRegistered;
+    (void)PreCondScope.Privatize();
+    // Initialize internal counter to 0 to calculate initial values of real
+    // counters.
+    LValue IV = CGF.EmitLValue(S.getIterationVariable());
+    CGF.EmitStoreOfScalar(
+        llvm::ConstantInt::getNullValue(
+            IV.getAddress()->getType()->getPointerElementType()),
+        CGF.EmitLValue(S.getIterationVariable()), /*isInit=*/true);
+    // Get initial values of real counters.
+    for (auto I : S.updates()) {
+      CGF.EmitIgnoredExpr(I);
+    }
   }
   // Check that loop is executed at least one time.
   CGF.EmitBranchOnBoolExpr(Cond, TrueBlock, FalseBlock, TrueCount);
diff --git a/clang/test/OpenMP/parallel_for_codegen.cpp b/clang/test/OpenMP/parallel_for_codegen.cpp
index 43bf83269655..6262e761e0da 100644
--- a/clang/test/OpenMP/parallel_for_codegen.cpp
+++ b/clang/test/OpenMP/parallel_for_codegen.cpp
@@ -2,6 +2,7 @@
 // RUN: %clang_cc1 -fopenmp -x c++ -std=c++11 -triple x86_64-unknown-unknown -fexceptions -fcxx-exceptions -emit-pch -o %t %s
 // RUN: %clang_cc1 -fopenmp -x c++ -triple x86_64-unknown-unknown -fexceptions -fcxx-exceptions -std=c++11 -include-pch %t -verify %s -emit-llvm -o - | FileCheck %s
 // RUN: %clang_cc1 -verify -triple x86_64-apple-darwin10 -fopenmp -fexceptions -fcxx-exceptions -gline-tables-only -x c++ -emit-llvm %s -o - | FileCheck %s --check-prefix=TERM_DEBUG
+// RUN: %clang_cc1 -verify -triple x86_64-apple-darwin10 -O1 -fopenmp -emit-llvm %s -o - | FileCheck %s --check-prefix=CLEANUP
 //
 // expected-no-diagnostics
 #ifndef HEADER
@@ -376,6 +377,7 @@ void runtime(float *a, float *b, float *c, float *d) {
 int foo() {return 0;};
 
 // TERM_DEBUG-LABEL: parallel_for
+// CLEANUP: parallel_for
 void parallel_for(float *a) {
 #pragma omp parallel for schedule(static, 5)
   // TERM_DEBUG-NOT: __kmpc_global_thread_num
@@ -388,13 +390,17 @@ void parallel_for(float *a) {
   // TERM_DEBUG:     [[TERM_LPAD]]
   // TERM_DEBUG:     call void @__clang_call_terminate
   // TERM_DEBUG:     unreachable
+  // CLEANUP-NOT: __kmpc_global_thread_num
+  // CLEANUP:     call void @__kmpc_for_static_init_4u({{.+}})
+  // CLEANUP:     call void @__kmpc_for_static_fini({{.+}})
+  // CLEANUP:     call {{.+}} @__kmpc_cancel_barrier({{.+}})
   for (unsigned i = 131071; i <= 2147483647; i += 127)
     a[i] += foo();
 }
 // Check source line corresponds to "#pragma omp parallel for schedule(static, 5)" above:
 // TERM_DEBUG-DAG: [[DBG_LOC_START]] = !DILocation(line: [[@LINE-4]],
-// TERM_DEBUG-DAG: [[DBG_LOC_END]] = !DILocation(line: [[@LINE-16]],
-// TERM_DEBUG-DAG: [[DBG_LOC_CANCEL]] = !DILocation(line: [[@LINE-17]],
+// TERM_DEBUG-DAG: [[DBG_LOC_END]] = !DILocation(line: [[@LINE-20]],
+// TERM_DEBUG-DAG: [[DBG_LOC_CANCEL]] = !DILocation(line: [[@LINE-21]],
 
 #endif // HEADER