[clang] 4faf3fc - [NFC][CLANG] Fix coverity remarks about large copy by values

[via cfe-commits]

Author: Manna, Soumi
Date: 2023-04-28T12:17:10-07:00
New Revision: 4faf3fcf3fb253cb3e68d6ae7b124e7a39f9ccff

URL: https://github.com/llvm/llvm-project/commit/4faf3fcf3fb253cb3e68d6ae7b124e7a39f9ccff
DIFF: https://github.com/llvm/llvm-project/commit/4faf3fcf3fb253cb3e68d6ae7b124e7a39f9ccff.diff

LOG: [NFC][CLANG] Fix coverity remarks about large copy by values

Reported By Static Analyzer Tool, Coverity:

Big parameter passed by value
Copying large values is inefficient, consider passing by reference; Low, medium, and high size thresholds for detection can be adjusted.

1. Inside "CodeGenModule.cpp" file, in clang::CodeGen::CodeGenModule::EmitBackendOptionsMetadata(clang::CodeGenOptions): A very large function call parameter exceeding the high threshold is passed by value.

pass_by_value: Passing parameter CodeGenOpts of type clang::CodeGenOptions const (size 2168 bytes) by value, which exceeds the high threshold of 512 bytes.

2. Inside "SemaType.cpp" file, in IsNoDerefableChunk(clang::DeclaratorChunk): A large function call parameter exceeding the low threshold is passed by value.

pass_by_value: Passing parameter Chunk of type clang::DeclaratorChunk (size 176 bytes) by value, which exceeds the low threshold of 128 bytes.

3. Inside "CGNonTrivialStruct.cpp" file, in <unnamed>::getParamAddrs<1ull, <0ull...>>(std::integer_sequence<unsigned long long, T2...>, std::array<clang::CharUnits, T1>, clang::CodeGen::FunctionArgList, clang::CodeGen::CodeGenFunction *): A large function call parameter exceeding the low threshold is passed by value.

.i. pass_by_value: Passing parameter Args of type clang::CodeGen::FunctionArgList (size 144 bytes) by value, which exceeds the low threshold of 128 bytes.

4. Inside "CGGPUBuiltin.cpp" file, in <unnamed>::containsNonScalarVarargs(clang::CodeGen::CodeGenFunction *, clang::CodeGen::CallArgList): A very large function call parameter exceeding the high threshold is passed by value.

i. pass_by_value: Passing parameter Args of type clang::CodeGen::CallArgList (size 1176 bytes) by value, which exceeds the high threshold of 512 bytes.

Reviewed By: tahonermann

Differential Revision: https://reviews.llvm.org/D149163

Added: 
    

Modified: 
    clang/lib/CodeGen/CGGPUBuiltin.cpp
    clang/lib/CodeGen/CGNonTrivialStruct.cpp
    clang/lib/CodeGen/CodeGenModule.cpp
    clang/lib/CodeGen/CodeGenModule.h
    clang/lib/Sema/SemaType.cpp

Removed: 
    


################################################################################
diff  --git a/clang/lib/CodeGen/CGGPUBuiltin.cpp b/clang/lib/CodeGen/CGGPUBuiltin.cpp
index 1183c2d7b5437..8451ebebfc0b7 100644
--- a/clang/lib/CodeGen/CGGPUBuiltin.cpp
+++ b/clang/lib/CodeGen/CGGPUBuiltin.cpp
@@ -125,7 +125,7 @@ packArgsIntoNVPTXFormatBuffer(CodeGenFunction *CGF, const CallArgList &Args) {
   }
 }
 
-bool containsNonScalarVarargs(CodeGenFunction *CGF, CallArgList Args) {
+bool containsNonScalarVarargs(CodeGenFunction *CGF, const CallArgList &Args) {
   return llvm::any_of(llvm::drop_begin(Args), [&](const CallArg &A) {
     return !A.getRValue(*CGF).isScalar();
   });

diff  --git a/clang/lib/CodeGen/CGNonTrivialStruct.cpp b/clang/lib/CodeGen/CGNonTrivialStruct.cpp
index a10e51b8cb441..98378e1386414 100644
--- a/clang/lib/CodeGen/CGNonTrivialStruct.cpp
+++ b/clang/lib/CodeGen/CGNonTrivialStruct.cpp
@@ -323,7 +323,7 @@ static const CGFunctionInfo &getFunctionInfo(CodeGenModule &CGM,
 template <size_t N, size_t... Ints>
 static std::array<Address, N> getParamAddrs(std::index_sequence<Ints...> IntSeq,
                                             std::array<CharUnits, N> Alignments,
-                                            FunctionArgList Args,
+                                            const FunctionArgList &Args,
                                             CodeGenFunction *CGF) {
   return std::array<Address, N>{
       {Address(CGF->Builder.CreateLoad(CGF->GetAddrOfLocalVar(Args[Ints])),

diff  --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index b8c45bc226ee1..367f802253e01 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -990,7 +990,7 @@ void CodeGenModule::EmitOpenCLMetadata() {
 }
 
 void CodeGenModule::EmitBackendOptionsMetadata(
-    const CodeGenOptions CodeGenOpts) {
+    const CodeGenOptions &CodeGenOpts) {
   if (getTriple().isRISCV()) {
     getModule().addModuleFlag(llvm::Module::Min, "SmallDataLimit",
                               CodeGenOpts.SmallDataLimit);

diff  --git a/clang/lib/CodeGen/CodeGenModule.h b/clang/lib/CodeGen/CodeGenModule.h
index 64c2902572376..0a0fdc89202f1 100644
--- a/clang/lib/CodeGen/CodeGenModule.h
+++ b/clang/lib/CodeGen/CodeGenModule.h
@@ -1711,7 +1711,7 @@ class CodeGenModule : public CodeGenTypeCache {
 
   /// Emit the module flag metadata used to pass options controlling the
   /// the backend to LLVM.
-  void EmitBackendOptionsMetadata(const CodeGenOptions CodeGenOpts);
+  void EmitBackendOptionsMetadata(const CodeGenOptions &CodeGenOpts);
 
   /// Emits OpenCL specific Metadata e.g. OpenCL version.
   void EmitOpenCLMetadata();

diff  --git a/clang/lib/Sema/SemaType.cpp b/clang/lib/Sema/SemaType.cpp
index be44803947501..7fdfadd9a34d2 100644
--- a/clang/lib/Sema/SemaType.cpp
+++ b/clang/lib/Sema/SemaType.cpp
@@ -4553,7 +4553,7 @@ static bool hasOuterPointerLikeChunk(const Declarator &D, unsigned endIndex) {
   return false;
 }
 
-static bool IsNoDerefableChunk(DeclaratorChunk Chunk) {
+static bool IsNoDerefableChunk(const DeclaratorChunk &Chunk) {
   return (Chunk.Kind == DeclaratorChunk::Pointer ||
           Chunk.Kind == DeclaratorChunk::Array);
 }