From c8443343ef2f6f1e7e11c12fe16eaf9e94b4c7e9 Mon Sep 17 00:00:00 2001
From: Fraser Cormack <fraser@codeplay.com>
Date: Thu, 4 Jul 2024 11:52:56 +0100
Subject: [PATCH] [SYCLLowerIR] Fix warnings when std::moving temporaries
 (#14281)

Moving a temporary variable prevents copy ellision, and by default
produces a compiler warning.

This PR also fixes up the naming of a few nearby variables to better
conform with LLVM (and the surrounding code).
---
 llvm/include/llvm/SYCLLowerIR/ModuleSplitter.h |  6 +++---
 llvm/include/llvm/SYCLLowerIR/Support.h        |  9 +++------
 llvm/lib/SYCLLowerIR/ModuleSplitter.cpp        | 11 +++++------
 llvm/tools/sycl-post-link/sycl-post-link.cpp   |  8 ++++----
 4 files changed, 15 insertions(+), 19 deletions(-)

diff --git a/llvm/include/llvm/SYCLLowerIR/ModuleSplitter.h b/llvm/include/llvm/SYCLLowerIR/ModuleSplitter.h
index 2465bd212b6e0..f4214bb82cecf 100644
--- a/llvm/include/llvm/SYCLLowerIR/ModuleSplitter.h
+++ b/llvm/include/llvm/SYCLLowerIR/ModuleSplitter.h
@@ -237,7 +237,7 @@ class ModuleSplitterBase {
   Module &getInputModule() { return Input.getModule(); }
 
   std::unique_ptr<Module> releaseInputModule() {
-    return std::move(Input.releaseModulePtr());
+    return Input.releaseModulePtr();
   }
 
 public:
@@ -274,9 +274,9 @@ getDeviceCodeSplitter(ModuleDesc &&MD, IRSplitMode Mode, bool IROutputOnly,
                       bool EmitOnlyKernelsAsEntryPoints);
 
 #ifndef NDEBUG
-void dumpEntryPoints(const EntryPointSet &C, const char *msg = "", int Tab = 0);
+void dumpEntryPoints(const EntryPointSet &C, const char *Msg = "", int Tab = 0);
 void dumpEntryPoints(const Module &M, bool OnlyKernelsAreEntryPoints = false,
-                     const char *msg = "", int Tab = 0);
+                     const char *Msg = "", int Tab = 0);
 #endif // NDEBUG
 
 struct SplitModule {
diff --git a/llvm/include/llvm/SYCLLowerIR/Support.h b/llvm/include/llvm/SYCLLowerIR/Support.h
index ef537bbcd8b8d..e41aac7e24c85 100644
--- a/llvm/include/llvm/SYCLLowerIR/Support.h
+++ b/llvm/include/llvm/SYCLLowerIR/Support.h
@@ -22,12 +22,9 @@
   } while (false)
 
 #define CHECK_AND_EXIT(E)                                                      \
-  {                                                                            \
-    Error LocE = std::move(E);                                                 \
-    if (LocE) {                                                                \
-      logAllUnhandledErrors(std::move(LocE), WithColor::error(errs()));        \
-      exit(1);                                                                 \
-    }                                                                          \
+  if (Error LocE = E) {                                                        \
+    logAllUnhandledErrors(std::move(LocE), WithColor::error(errs()));          \
+    exit(1);                                                                   \
   }
 
 namespace llvm {
diff --git a/llvm/lib/SYCLLowerIR/ModuleSplitter.cpp b/llvm/lib/SYCLLowerIR/ModuleSplitter.cpp
index 68104e85e4362..d9a11cd4a85b4 100644
--- a/llvm/lib/SYCLLowerIR/ModuleSplitter.cpp
+++ b/llvm/lib/SYCLLowerIR/ModuleSplitter.cpp
@@ -1154,8 +1154,8 @@ SmallVector<ModuleDesc, 2> splitByESIMD(ModuleDesc &&MD,
   }
 
   if (EntryPointGroups.size() == 1) {
-    Result.emplace_back(std::move(MD.releaseModulePtr()),
-                        std::move(EntryPointGroups[0]), MD.Props);
+    Result.emplace_back(MD.releaseModulePtr(), std::move(EntryPointGroups[0]),
+                        MD.Props);
     return Result;
   }
 
@@ -1164,8 +1164,7 @@ SmallVector<ModuleDesc, 2> splitByESIMD(ModuleDesc &&MD,
     if (Group.isEsimd()) {
       // For ESIMD module, we use full call graph of all entry points and all
       // ESIMD functions.
-      Result.emplace_back(
-          std::move(extractESIMDSubModule(MD, std::move(Group), CG)));
+      Result.emplace_back(extractESIMDSubModule(MD, std::move(Group), CG));
     } else {
       // For non-ESIMD module we only use non-ESIMD functions. Additional filter
       // is needed, because there could be uses of ESIMD functions from
@@ -1173,9 +1172,9 @@ SmallVector<ModuleDesc, 2> splitByESIMD(ModuleDesc &&MD,
       // modules are expected to be linked back together after ESIMD functions
       // were processed and therefore it is fine to return an "incomplete"
       // module here.
-      Result.emplace_back(std::move(extractCallGraph(
+      Result.emplace_back(extractCallGraph(
           MD, std::move(Group), CG,
-          [=](const Function *F) -> bool { return !isESIMDFunction(*F); })));
+          [=](const Function *F) -> bool { return !isESIMDFunction(*F); }));
     }
   }
 
diff --git a/llvm/tools/sycl-post-link/sycl-post-link.cpp b/llvm/tools/sycl-post-link/sycl-post-link.cpp
index 252f070652c4c..6760b2b1c6f7e 100644
--- a/llvm/tools/sycl-post-link/sycl-post-link.cpp
+++ b/llvm/tools/sycl-post-link/sycl-post-link.cpp
@@ -432,10 +432,10 @@ module_split::ModuleDesc link(module_split::ModuleDesc &&MD1,
   std::vector<std::string> Names;
   MD1.saveEntryPointNames(Names);
   MD2.saveEntryPointNames(Names);
-  bool link_error = llvm::Linker::linkModules(
-      MD1.getModule(), std::move(MD2.releaseModulePtr()));
+  bool LinkError =
+      llvm::Linker::linkModules(MD1.getModule(), MD2.releaseModulePtr());
 
-  if (link_error) {
+  if (LinkError) {
     error(" error when linking SYCL and ESIMD modules");
   }
   module_split::ModuleDesc Res(MD1.releaseModulePtr(), std::move(Names));
@@ -491,7 +491,7 @@ processSpecConstantsWithDefaultValues(const module_split::ModuleDesc &MD) {
          "This property should be true since the presence of SpecConsts "
          "has been checked before the run of the pass");
   NewModuleDesc->rebuildEntryPoints();
-  return std::move(NewModuleDesc);
+  return NewModuleDesc;
 }
 
 constexpr int MAX_COLUMNS_IN_FILE_TABLE = 3;