[CIR][NFC] Fix warnings in ClangIR code (#133134)

This fixes unused variable warnings that have crept into the ClangIR
code. In some cases the variable will be needed later, but all unused
variables are being removed here. They can be reintroduced when they are
needed.

Author: andykaylor

clang/lib/CIR/CodeGen/CIRGenExpr.cpp

@@ -170,7 +170,7 @@ mlir::Value CIRGenFunction::evaluateExprAsBool(const Expr *e) {
   SourceLocation loc = e->getExprLoc();
 
   assert(!cir::MissingFeatures::pgoUse());
-  if (const MemberPointerType *MPT = e->getType()->getAs<MemberPointerType>()) {
+  if (e->getType()->getAs<MemberPointerType>()) {
     cgm.errorNYI(e->getSourceRange(),
                  "evaluateExprAsBool: member pointer type");
     return createDummyValue(getLoc(loc), boolTy);

clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp

@@ -1366,8 +1366,7 @@ mlir::Value ScalarExprEmitter::VisitUnaryExprOrTypeTraitExpr(
   const mlir::Location loc = cgf.getLoc(e->getSourceRange());
   if (auto kind = e->getKind();
       kind == UETT_SizeOf || kind == UETT_DataSizeOf) {
-    if (const VariableArrayType *variableArrTy =
-            cgf.getContext().getAsVariableArrayType(typeToSize)) {
+    if (cgf.getContext().getAsVariableArrayType(typeToSize)) {
       cgf.getCIRGenModule().errorNYI(e->getSourceRange(),
                                      "sizeof operator for VariableArrayType",
                                      e->getStmtClassName());

clang/lib/CIR/CodeGen/CIRGenFunction.h

@@ -243,10 +243,6 @@ class CIRGenFunction : public CIRGenTypeCache {
     // class is upstreamed.
     CIRGenFunction &cgf;
 
-    // Block containing cleanup code for things initialized in this lexical
-    // context (scope).
-    mlir::Block *cleanupBlock = nullptr;
-
     // Points to the scope entry block. This is useful, for instance, for
     // helping to insert allocas before finalizing any recursive CodeGen from
     // switches.

clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp

@@ -126,21 +126,6 @@ static mlir::Value emitToMemory(mlir::ConversionPatternRewriter &rewriter,
   return value;
 }
 
-static mlir::Value
-emitCirAttrToMemory(mlir::Operation *parentOp, mlir::Attribute attr,
-                    mlir::ConversionPatternRewriter &rewriter,
-                    const mlir::TypeConverter *converter,
-                    mlir::DataLayout const &dataLayout) {
-
-  mlir::Value loweredValue =
-      lowerCirAttrAsValue(parentOp, attr, rewriter, converter);
-  if (auto boolAttr = mlir::dyn_cast<cir::BoolAttr>(attr)) {
-    return emitToMemory(rewriter, dataLayout, boolAttr.getType(), loweredValue);
-  }
-
-  return loweredValue;
-}
-
 mlir::LLVM::Linkage convertLinkage(cir::GlobalLinkageKind linkage) {
   using CIR = cir::GlobalLinkageKind;
   using LLVM = mlir::LLVM::Linkage;
@@ -261,7 +246,7 @@ mlir::Value CIRAttrToValue::visitCirAttr(cir::ConstArrayAttr attr) {
   mlir::Location loc = parentOp->getLoc();
   mlir::Value result;
 
-  if (auto zeros = attr.getTrailingZerosNum()) {
+  if (attr.hasTrailingZeros()) {
     mlir::Type arrayTy = attr.getType();
     result = rewriter.create<mlir::LLVM::ZeroOp>(
         loc, converter->convertType(arrayTy));
@@ -1251,13 +1236,12 @@ void ConvertCIRToLLVMPass::runOnOperation() {
   patterns.add<CIRToLLVMStoreOpLowering>(converter, patterns.getContext(), dl);
   patterns.add<CIRToLLVMGlobalOpLowering>(converter, patterns.getContext(), dl);
   patterns.add<CIRToLLVMCastOpLowering>(converter, patterns.getContext(), dl);
-  patterns.add<CIRToLLVMConstantOpLowering>(converter, patterns.getContext(),
-                                            dl);
   patterns.add<
       // clang-format off
                CIRToLLVMBinOpLowering,
                CIRToLLVMBrCondOpLowering,
                CIRToLLVMBrOpLowering,
+               CIRToLLVMConstantOpLowering,
                CIRToLLVMFuncOpLowering,
                CIRToLLVMTrapOpLowering,
                CIRToLLVMUnaryOpLowering

clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.h

@@ -113,13 +113,10 @@ class CIRToLLVMStoreOpLowering
 
 class CIRToLLVMConstantOpLowering
     : public mlir::OpConversionPattern<cir::ConstantOp> {
-  mlir::DataLayout const &dataLayout;
-
 public:
   CIRToLLVMConstantOpLowering(const mlir::TypeConverter &typeConverter,
-                              mlir::MLIRContext *context,
-                              mlir::DataLayout const &dataLayout)
-      : OpConversionPattern(typeConverter, context), dataLayout(dataLayout) {
+                              mlir::MLIRContext *context)
+      : OpConversionPattern(typeConverter, context) {
     setHasBoundedRewriteRecursion();
   }