Improve obvious-most-derived-type devirtualization:
* if the base is produced by a series of derived-to-base conversions, check
the expression inside them when looking for an expression with a known
dynamic type
* step past MaterializeTemporaryExprs when checking for a known dynamic type
* when checking for a known dynamic type, treat all class prvalues as having
a known dynamic type after skipping all relevant rvalue subobject
adjustments
* treat callees formed by pointer-to-member access for a non-reference member
type like callees formed by member access.
llvm-svn: 285954
diff --git a/clang/lib/AST/Expr.cpp b/clang/lib/AST/Expr.cpp
index 9cf9e86..53ab5cf 100644
--- a/clang/lib/AST/Expr.cpp
+++ b/clang/lib/AST/Expr.cpp
@@ -35,9 +35,33 @@
#include <cstring>
using namespace clang;
-const CXXRecordDecl *Expr::getBestDynamicClassType() const {
- const Expr *E = ignoreParenBaseCasts();
+const Expr *Expr::getBestDynamicClassTypeExpr() const {
+ const Expr *E = this;
+ while (true) {
+ E = E->ignoreParenBaseCasts();
+ // Follow the RHS of a comma operator.
+ if (auto *BO = dyn_cast<BinaryOperator>(E)) {
+ if (BO->getOpcode() == BO_Comma) {
+ E = BO->getRHS();
+ continue;
+ }
+ }
+
+ // Step into initializer for materialized temporaries.
+ if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(E)) {
+ E = MTE->GetTemporaryExpr();
+ continue;
+ }
+
+ break;
+ }
+
+ return E;
+}
+
+const CXXRecordDecl *Expr::getBestDynamicClassType() const {
+ const Expr *E = getBestDynamicClassTypeExpr();
QualType DerivedType = E->getType();
if (const PointerType *PTy = DerivedType->getAs<PointerType>())
DerivedType = PTy->getPointeeType();