commit cc5958e94fba7aa4d7468e6b7d5bdf98fb3f3df4
author Tonko Sabolčec <tsabolcec@google.com> Tue May 25 13:33:07 2021
committer GitHub <noreply@github.com> Tue May 25 13:33:07 2021
tree f618080eb0022d24bcc6cd44c9342664c1c4fbc9
parent 4317381e1fa6b97aa661d8f274121ca4fd5fe889

[fuzzer] Do not generate void expressions in sizeof (#132)

tools/fuzzer/constraints.cc

diff --git a/tools/fuzzer/constraints.cc b/tools/fuzzer/constraints.cc
index 5a4146f..1c58736 100644
--- a/tools/fuzzer/constraints.cc
+++ b/tools/fuzzer/constraints.cc
@@ -228,9 +228,7 @@
   }
 
   if (std::holds_alternative<AnyType>(ptr_types_)) {
-    TypeConstraints retval = TypeConstraints::all();
-    retval.scalar_types_[ScalarType::Void] = false;
-    return retval;
+    return TypeConstraints::all_non_void();
   }
 
   const auto* specific_types_ptr =

tools/fuzzer/constraints.h

diff --git a/tools/fuzzer/constraints.h b/tools/fuzzer/constraints.h
index 51acafc..5bda4de 100644
--- a/tools/fuzzer/constraints.h
+++ b/tools/fuzzer/constraints.h
@@ -92,9 +92,9 @@
     return retval;
   }
 
-  static TypeConstraints all() {
+  static TypeConstraints all_non_void() {
     TypeConstraints retval;
-    retval.scalar_types_ = ScalarMask::all_set();
+    retval.scalar_types_ = ~ScalarMask(ScalarType::Void);
     retval.tagged_types_ = AnyType{};
     retval.ptr_types_ = AnyType{};
     retval.array_types_ = AnyType{};

tools/fuzzer/constraints_test.cc

diff --git a/tools/fuzzer/constraints_test.cc b/tools/fuzzer/constraints_test.cc
index 8bce256..192a8cd 100644
--- a/tools/fuzzer/constraints_test.cc
+++ b/tools/fuzzer/constraints_test.cc
@@ -25,7 +25,7 @@
   TypeConstraints float_only = FLOAT_TYPES;
   TypeConstraints int_only = INT_TYPES;
 
-  TypeConstraints any = TypeConstraints::all();
+  TypeConstraints any = TypeConstraints::all_non_void();
   TypeConstraints none;
 
   PointerType void_ptr_type{QualifiedType(ScalarType::Void)};
@@ -85,7 +85,7 @@
   EXPECT_THAT(test_struct.allows_non_void_pointer(), IsFalse());
   EXPECT_THAT(test_struct.allows_void_pointer(), IsFalse());
 
-  TypeConstraints any = TypeConstraints::all();
+  TypeConstraints any = TypeConstraints::all_non_void();
   TypeConstraints none;
 
   EXPECT_THAT(any.allows_tagged_types(), IsTrue());
@@ -159,7 +159,7 @@
   // void types :(
   EXPECT_THAT(void_constraints.allows_any_of(ScalarType::Void), IsFalse());
 
-  TypeConstraints any = TypeConstraints::all();
+  TypeConstraints any = TypeConstraints::all_non_void();
   TypeConstraints none;
 
   EXPECT_THAT(any.allows_type(const_int_ptr), IsTrue());
@@ -176,7 +176,7 @@
   EnumType unscoped_enum("UnscopedEnum", false);
   EnumType specific_enum("SpecificEnum", true);
 
-  TypeConstraints any = TypeConstraints::all();
+  TypeConstraints any = TypeConstraints::all_non_void();
   TypeConstraints none;
   TypeConstraints bool_ctx = TypeConstraints::all_in_bool_ctx();
   TypeConstraints only_specific = TypeConstraints(specific_enum);
@@ -217,7 +217,7 @@
   ArrayType array_of_ptrs = ArrayType(int_ptr, 3);
   PointerType ptr_to_array = PointerType(QualifiedType(array_of_three));
 
-  TypeConstraints any = TypeConstraints::all();
+  TypeConstraints any = TypeConstraints::all_non_void();
   EXPECT_THAT(any.allows_type(array_of_three), IsTrue());
   EXPECT_THAT(any.allows_type(array_of_four), IsTrue());
   EXPECT_THAT(any.allows_type(array2d), IsTrue());

tools/fuzzer/expr_gen.cc

diff --git a/tools/fuzzer/expr_gen.cc b/tools/fuzzer/expr_gen.cc
index f8ed78b..a3c5a09 100644
--- a/tools/fuzzer/expr_gen.cc
+++ b/tools/fuzzer/expr_gen.cc
@@ -903,7 +903,7 @@
     return SizeofExpr(std::move(maybe_type.value()));
   }
 
-  auto maybe_expr = gen_with_weights(weights, TypeConstraints::all());
+  auto maybe_expr = gen_with_weights(weights, TypeConstraints::all_non_void());
   if (!maybe_expr.has_value()) {
     return {};
   }