[OPENMP]Allow to redefine entry for the variables definitions.

If the variable was declared and marked as declare target, a new offload
entry with size 0 is created. But if later a definition is created and
marked as declare target, this definition is not added to the entry set
and the definition remains not mapped to the target. Patch fixes this
problem allowing to redefine the size and linkage for
previously registered declaration.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@355960 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/CGOpenMPRuntime.cpp

@@ -3760,14 +3760,29 @@ void CGOpenMPRuntime::OffloadEntriesInfoManagerTy::
            "Entry not initialized!");
     assert((!Entry.getAddress() || Entry.getAddress() == Addr) &&
            "Resetting with the new address.");
-    if (Entry.getAddress() && hasDeviceGlobalVarEntryInfo(VarName))
+    if (Entry.getAddress() && hasDeviceGlobalVarEntryInfo(VarName)) {
+      if (Entry.getVarSize().isZero()) {
+        Entry.setVarSize(VarSize);
+        Entry.setLinkage(Linkage);
+      }
       return;
-    Entry.setAddress(Addr);
+    }
     Entry.setVarSize(VarSize);
     Entry.setLinkage(Linkage);
+    Entry.setAddress(Addr);
   } else {
-    if (hasDeviceGlobalVarEntryInfo(VarName))
+    if (hasDeviceGlobalVarEntryInfo(VarName)) {
+      auto &Entry = OffloadEntriesDeviceGlobalVar[VarName];
+      assert(Entry.isValid() && Entry.getFlags() == Flags &&
+             "Entry not initialized!");
+      assert((!Entry.getAddress() || Entry.getAddress() == Addr) &&
+             "Resetting with the new address.");
+      if (Entry.getVarSize().isZero()) {
+        Entry.setVarSize(VarSize);
+        Entry.setLinkage(Linkage);
+      }
       return;
+    }
     OffloadEntriesDeviceGlobalVar.try_emplace(
         VarName, OffloadingEntriesNum, Addr, VarSize, Flags, Linkage);
     ++OffloadingEntriesNum;

test/OpenMP/declare_target_codegen.cpp

@@ -17,6 +17,7 @@
 // CHECK-NOT: @{{hhh|ggg|fff|eee}} =
 // CHECK-DAG: @aaa = external global i32,
 // CHECK-DAG: @bbb = global i32 0,
+// CHECK-DAG: weak constant %struct.__tgt_offload_entry { i8* bitcast (i32* @bbb to i8*),
 // CHECK-DAG: @ccc = external global i32,
 // CHECK-DAG: @ddd = global i32 0,
 // CHECK-DAG: @hhh_decl_tgt_link_ptr = common global i32* null
@@ -31,24 +32,35 @@
 // CHECK-DAG: [[STAT:@.+stat]] = internal global %struct.S zeroinitializer,
 // CHECK-DAG: [[STAT_REF:@.+]] = internal constant %struct.S* [[STAT]]
 // CHECK-DAG: @out_decl_target = global i32 0,
-// CHECK-DAG: @llvm.used = appending global [6 x i8*] [i8* bitcast (void ()* @__omp_offloading__{{.+}}_globals_l[[@LINE+69]]_ctor to i8*), i8* bitcast (void ()* @__omp_offloading__{{.+}}_stat_l[[@LINE+70]]_ctor to i8*),
+// CHECK-DAG: @llvm.used = appending global [6 x i8*] [i8* bitcast (void ()* @__omp_offloading__{{.+}}_globals_l[[@LINE+80]]_ctor to i8*), i8* bitcast (void ()* @__omp_offloading__{{.+}}_stat_l[[@LINE+81]]_ctor to i8*),
 // CHECK-DAG: @llvm.compiler.used = appending global [1 x i8*] [i8* bitcast (%struct.S** [[STAT_REF]] to i8*)],
 
 // CHECK-DAG: define {{.*}}i32 @{{.*}}{{foo|bar|baz2|baz3|FA|f_method}}{{.*}}()
 // CHECK-DAG: define {{.*}}void @{{.*}}TemplateClass{{.*}}(%class.TemplateClass* %{{.*}})
 // CHECK-DAG: define {{.*}}i32 @{{.*}}TemplateClass{{.*}}f_method{{.*}}(%class.TemplateClass* %{{.*}})
-// CHECK-DAG: define {{.*}}void @__omp_offloading__{{.*}}_globals_l[[@LINE+63]]_ctor()
+// CHECK-DAG: define {{.*}}void @__omp_offloading__{{.*}}_globals_l[[@LINE+74]]_ctor()
 
 #ifndef HEADER
 #define HEADER
 
+#pragma omp declare target
+extern int bbb;
+#pragma omp end declare target
+#pragma omp declare target
+extern int bbb;
+#pragma omp end declare target
+
 #pragma omp declare target
 extern int aaa;
 int bbb = 0;
 extern int ccc;
 int ddd = 0;
 #pragma omp end declare target
 
+#pragma omp declare target
+extern int bbb;
+#pragma omp end declare target
+
 extern int eee;
 int fff = 0;
 extern int ggg;