changes after review

llvm · Jan 25, 2024 · 6b829fa · 6b829fa
1 parent 124db70
commit 6b829fa
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Showing 4 changed files with 33 additions and 41 deletions.
diff --git a/clang/lib/CIR/CodeGen/CIRGenDecl.cpp b/clang/lib/CIR/CodeGen/CIRGenDecl.cpp
@@ -151,33 +151,41 @@ CIRGenFunction::buildAutoVarAlloca(const VarDecl &D) {
       assert(!UnimplementedFeature::shouldEmitLifetimeMarkers());
     }
   } else { // not openmp nor constant sized type
+    bool VarAllocated = false;
     if (getLangOpts().OpenMPIsTargetDevice)
       llvm_unreachable("NYI");
 
-    if (!DidCallStackSave) {
-      // Save the stack.
-      auto defaultTy = AllocaInt8PtrTy;
-      CharUnits Align = CharUnits::fromQuantity(
-          CGM.getDataLayout().getAlignment(defaultTy, false));
-      Address Stack = CreateTempAlloca(defaultTy, Align, loc, "saved_stack");
+    if (!VarAllocated) {
+      if (!DidCallStackSave) {
+        // Save the stack.
+        auto defaultTy = AllocaInt8PtrTy;
+        CharUnits Align = CharUnits::fromQuantity(
+            CGM.getDataLayout().getAlignment(defaultTy, false));
+        Address Stack = CreateTempAlloca(defaultTy, Align, loc, "saved_stack");
 
-      mlir::Value V = builder.createStackSave(loc, defaultTy);
-      assert(V.getType() == AllocaInt8PtrTy);
-      builder.createStore(loc, V, Stack);
+        mlir::Value V = builder.createStackSave(loc, defaultTy);
+        assert(V.getType() == AllocaInt8PtrTy);
+        builder.createStore(loc, V, Stack);
 
-      DidCallStackSave = true;
+        DidCallStackSave = true;
 
-      // Push a cleanup block and restore the stack there.
-      // FIXME: in general circumstances, this should be an EH cleanup.
-      pushStackRestore(NormalCleanup, Stack);
-    }
+        // Push a cleanup block and restore the stack there.
+        // FIXME: in general circumstances, this should be an EH cleanup.
+        pushStackRestore(NormalCleanup, Stack);
+      }
 
-    auto VlaSize = getVLASize(Ty);
-    mlir::Type mTy = convertTypeForMem(VlaSize.Type);
+      auto VlaSize = getVLASize(Ty);
+      mlir::Type mTy = convertTypeForMem(VlaSize.Type);
+
+      // Allocate memory for the array.
+      address = CreateTempAlloca(mTy, alignment, loc, "vla", VlaSize.NumElts,
+                                &allocaAddr, builder.saveInsertionPoint());
+    }
 
-    // Allocate memory for the array.
-    address = CreateTempAlloca(mTy, alignment, loc, "vla", VlaSize.NumElts,
-                               &allocaAddr, builder.saveInsertionPoint());
+    // If we have debug info enabled, properly describe the VLA dimensions for
+    // this type by registering the vla size expression for each of the
+    // dimensions.
+    assert(!UnimplementedFeature::generateDebugInfo());
   }
 
   emission.Addr = address;

diff --git a/clang/lib/CIR/CodeGen/CIRGenFunction.cpp b/clang/lib/CIR/CodeGen/CIRGenFunction.cpp
@@ -1423,9 +1423,12 @@ CIRGenFunction::getVLASize(const VariableArrayType *type) {
     }
   } while ((type = getContext().getAsVariableArrayType(elementType)));
 
+  assert(numElements && "Undefined elements number");
   return {numElements, elementType};
 }
 
+// TODO(cir): most part of this function can be shared between CIRGen
+// and traditional LLVM codegen
 void CIRGenFunction::buildVariablyModifiedType(QualType type) {
   assert(type->isVariablyModifiedType() &&
          "Must pass variably modified type to EmitVLASizes!");
@@ -1510,27 +1513,7 @@ void CIRGenFunction::buildVariablyModifiedType(QualType type) {
         mlir::Value &entry = VLASizeMap[sizeExpr];
         if (!entry) {
           mlir::Value size = buildScalarExpr(sizeExpr);
-
-          // // C11 6.7.6.2p5:
-          // //   If the size is an expression that is not an integer constant
-          // //   expression [...] each time it is evaluated it shall have a
-          // //   value greater than zero.
-          // if (SanOpts.has(SanitizerKind::VLABound)) {
-          //   SanitizerScope SanScope(this);
-          //   llvm::Value *Zero =
-          //   llvm::Constant::getNullValue(size->getType()); clang::QualType
-          //   SEType = sizeExpr->getType(); llvm::Value *CheckCondition =
-          //       SEType->isSignedIntegerType()
-          //           ? Builder.CreateICmpSGT(size, Zero)
-          //           : Builder.CreateICmpUGT(size, Zero);
-          //   llvm::Constant *StaticArgs[] = {
-          //       EmitCheckSourceLocation(sizeExpr->getBeginLoc()),
-          //       EmitCheckTypeDescriptor(SEType)};
-          //   EmitCheck(std::make_pair(CheckCondition,
-          //   SanitizerKind::VLABound),
-          //             SanitizerHandler::VLABoundNotPositive, StaticArgs,
-          //             size);
-          // }
+          assert(!UnimplementedFeature::sanitizeVLABound()); 
 
           // Always zexting here would be wrong if it weren't
           // undefined behavior to have a negative bound.

diff --git a/clang/lib/CIR/CodeGen/CIRGenFunction.h b/clang/lib/CIR/CodeGen/CIRGenFunction.h
@@ -93,7 +93,7 @@ class CIRGenFunction : public CIRGenTypeCache {
   llvm::DenseMap<const OpaqueValueExpr *, LValue> OpaqueLValues;
   llvm::DenseMap<const OpaqueValueExpr *, RValue> OpaqueRValues;
 
-  // VLASizeMap - This keeps track of the associated size for each VLA type.
+  // This keeps track of the associated size for each VLA type.
   // We track this by the size expression rather than the type itself because
   // in certain situations, like a const qualifier applied to an VLA typedef,
   // multiple VLA types can share the same size expression.

diff --git a/clang/lib/CIR/CodeGen/UnimplementedFeatureGuarding.h b/clang/lib/CIR/CodeGen/UnimplementedFeatureGuarding.h
@@ -58,6 +58,7 @@ struct UnimplementedFeature {
   static bool emitCheckedInBoundsGEP() { return false; }
   static bool pointerOverflowSanitizer() { return false; }
   static bool sanitizeDtor() { return false; }
+  static bool sanitizeVLABound() { return false; }
 
   // ObjC
   static bool setObjCGCLValueClass() { return false; }