[AMDGPU] When unifying metadata, add operands to named metadata individually

[kzhuravl]

Summary

This was causing verifier to fail for llvm.ident

[rampitec]

LGTM

lib/Target/AMDGPU/AMDGPUUnifyMetadata.cpp

bool unifyExtensionMD(Module &M, StringRef Name) {
     SmallVector<Metadata *, 4> All;
     for (const auto &MD : NamedMD->operands())
       for (const auto &Op : MD->operands())
         if (std::find(All.begin(), All.end(), Op.get()) == All.end())
           All.push_back(Op.get());
 
     NamedMD->eraseFromParent();
     NamedMD = M.getOrInsertNamedMetadata(Name);
-    NamedMD->addOperand(MDNode::get(M.getContext(), All));
+    for (const auto &MD : All)
+      NamedMD->addOperand(MDNode::get(M.getContext(), MD));
+
     return true;
   }
 };
 
 } // end anonymous namespace
 
 char AMDGPUUnifyMetadata::ID = 0;
 
const char* Exts[] = {
       kOCLMD::UsedExt,
       kOCLMD::UsedOptCoreFeat,
       kOCLMD::CompilerOptions,
       kOCLMD::LLVMIdent
   };
 
   bool Changed = false;
 
-  for (auto &I:Vers)
+  for (auto &I : Vers)
     Changed |= unifyVersionMD(M, I, true);
 
-  for (auto &I:Exts)
+  for (auto &I : Exts)
     Changed |= unifyExtensionMD(M, I);
 
   return Changed;
 }
 
 bool AMDGPUUnifyMetadata::runOnFunction(Function &F) {
   return runOnModule(*F.getParent());
 }

test/CodeGen/AMDGPU/unify-metadata.ll

 ; RUN: opt -mtriple=amdgcn--amdhsa -amdgpu-unify-metadata -S < %s | FileCheck -check-prefix=ALL %s
 
 ; This test check that we have a singe metadata value after linking several
 ; modules for records such as opencl.ocl.version, llvm.ident and similar.
 
 ; ALL-DAG: !opencl.ocl.version = !{![[OCL_VER:[0-9]+]]}
-; ALL-DAG: !llvm.ident = !{![[LLVM_IDENT:[0-9]+]]}
-; ALL-DAG: !opencl.used.extensions = !{![[USED_EXT:[0-9]+]]}
+; ALL-DAG: !llvm.ident = !{![[LLVM_IDENT_0:[0-9]+]], ![[LLVM_IDENT_1:[0-9]+]]}
+; ALL-DAG: !opencl.used.extensions = !{![[USED_EXT_0:[0-9]+]], ![[USED_EXT_1:[0-9]+]], ![[USED_EXT_2:[0-9]+]]}
+
 ; ALL-DAG: ![[OCL_VER]] = !{i32 1, i32 2}
-; ALL-DAG: ![[LLVM_IDENT]] = !{!"clang version 4.0 "}
-; ALL-DAG: ![[USED_EXT]] = !{!"cl_images", !"cl_khr_fp16", !"cl_doubles"}
+; ALL-DAG: ![[LLVM_IDENT_0]] = !{!"clang version 4.0"}
+; ALL-DAG: ![[LLVM_IDENT_1]] = !{!"clang version 4.0 (rLXXXXXX)"}
+; ALL-DAG: ![[USED_EXT_0]] = !{!"cl_images"}
+; ALL-DAG: ![[USED_EXT_1]] = !{!"cl_khr_fp16"}
+; ALL-DAG: ![[USED_EXT_2]] = !{!"cl_doubles"}
 
 define void @test() {
    ret void
 }
 
 !opencl.ocl.version = !{!1, !0, !0, !0}
-!llvm.ident = !{!2, !2, !2, !2}
+!llvm.ident = !{!2, !2, !2, !2, !6}
 !opencl.used.extensions = !{!3, !3, !4, !5}
 
 !0 = !{i32 2, i32 0}
 !1 = !{i32 1, i32 2}
-!2 = !{!"clang version 4.0 "}
+!2 = !{!"clang version 4.0"}
 !3 = !{!"cl_images", !"cl_khr_fp16"}
 !4 = !{!"cl_images", !"cl_doubles"}
 !5 = !{}
+!6 = !{!"clang version 4.0 (rLXXXXXX)"}