[clang][bytecode] Diagnose volatile writes (#160350)
diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp
index b4da999..0b7b6cd 100644
--- a/clang/lib/AST/ByteCode/Compiler.cpp
+++ b/clang/lib/AST/ByteCode/Compiler.cpp
@@ -2934,8 +2934,9 @@
// For everyhing else, use local variables.
if (SubExprT) {
bool IsConst = SubExpr->getType().isConstQualified();
- unsigned LocalIndex =
- allocateLocalPrimitive(E, *SubExprT, IsConst, E->getExtendingDecl());
+ bool IsVolatile = SubExpr->getType().isVolatileQualified();
+ unsigned LocalIndex = allocateLocalPrimitive(
+ E, *SubExprT, IsConst, IsVolatile, E->getExtendingDecl());
if (!this->visit(SubExpr))
return false;
if (!this->emitSetLocal(*SubExprT, LocalIndex, E))
@@ -4452,6 +4453,9 @@
if (!this->visit(LHS))
return false;
+ if (LHS->getType().isVolatileQualified())
+ return this->emitInvalidStore(LHS->getType().getTypePtr(), E);
+
// We don't support assignments in C.
if (!Ctx.getLangOpts().CPlusPlus && !this->emitInvalid(E))
return false;
@@ -4560,13 +4564,14 @@
template <class Emitter>
unsigned Compiler<Emitter>::allocateLocalPrimitive(
- DeclTy &&Src, PrimType Ty, bool IsConst, const ValueDecl *ExtendingDecl,
- ScopeKind SC, bool IsConstexprUnknown) {
+ DeclTy &&Src, PrimType Ty, bool IsConst, bool IsVolatile,
+ const ValueDecl *ExtendingDecl, ScopeKind SC, bool IsConstexprUnknown) {
// FIXME: There are cases where Src.is<Expr*>() is wrong, e.g.
// (int){12} in C. Consider using Expr::isTemporaryObject() instead
// or isa<MaterializeTemporaryExpr>().
Descriptor *D = P.createDescriptor(Src, Ty, nullptr, Descriptor::InlineDescMD,
- IsConst, isa<const Expr *>(Src));
+ IsConst, isa<const Expr *>(Src),
+ /*IsMutable=*/false, IsVolatile);
D->IsConstexprUnknown = IsConstexprUnknown;
Scope::Local Local = this->createLocal(D);
if (auto *VD = dyn_cast_if_present<ValueDecl>(Src.dyn_cast<const Decl *>()))
@@ -4874,7 +4879,8 @@
if (VarT) {
unsigned Offset = this->allocateLocalPrimitive(
- VD, *VarT, VD->getType().isConstQualified(), nullptr, ScopeKind::Block,
+ VD, *VarT, VD->getType().isConstQualified(),
+ VD->getType().isVolatileQualified(), nullptr, ScopeKind::Block,
IsConstexprUnknown);
if (Init) {
// If this is a toplevel declaration, create a scope for the
diff --git a/clang/lib/AST/ByteCode/Compiler.h b/clang/lib/AST/ByteCode/Compiler.h
index 09599b3..5c46f75 100644
--- a/clang/lib/AST/ByteCode/Compiler.h
+++ b/clang/lib/AST/ByteCode/Compiler.h
@@ -327,6 +327,7 @@
/// Creates a local primitive value.
unsigned allocateLocalPrimitive(DeclTy &&Decl, PrimType Ty, bool IsConst,
+ bool IsVolatile = false,
const ValueDecl *ExtendingDecl = nullptr,
ScopeKind SC = ScopeKind::Block,
bool IsConstexprUnknown = false);
diff --git a/clang/lib/AST/ByteCode/Context.cpp b/clang/lib/AST/ByteCode/Context.cpp
index 306f95c..683e916 100644
--- a/clang/lib/AST/ByteCode/Context.cpp
+++ b/clang/lib/AST/ByteCode/Context.cpp
@@ -567,9 +567,15 @@
// Assign descriptors to all parameters.
// Composite objects are lowered to pointers.
for (const ParmVarDecl *PD : FuncDecl->parameters()) {
+ bool IsConst = PD->getType().isConstQualified();
+ bool IsVolatile = PD->getType().isVolatileQualified();
+
OptPrimType T = classify(PD->getType());
PrimType PT = T.value_or(PT_Ptr);
- Descriptor *Desc = P->createDescriptor(PD, PT);
+ Descriptor *Desc = P->createDescriptor(PD, PT, nullptr, std::nullopt,
+ IsConst, /*IsTemporary=*/false,
+ /*IsMutable=*/false, IsVolatile);
+
ParamDescriptors.insert({ParamOffset, {PT, Desc}});
ParamOffsets.push_back(ParamOffset);
ParamOffset += align(primSize(PT));
@@ -595,9 +601,14 @@
// Assign descriptors to all parameters.
// Composite objects are lowered to pointers.
for (const ParmVarDecl *PD : BD->parameters()) {
+ bool IsConst = PD->getType().isConstQualified();
+ bool IsVolatile = PD->getType().isVolatileQualified();
+
OptPrimType T = classify(PD->getType());
PrimType PT = T.value_or(PT_Ptr);
- Descriptor *Desc = P->createDescriptor(PD, PT);
+ Descriptor *Desc = P->createDescriptor(PD, PT, nullptr, std::nullopt,
+ IsConst, /*IsTemporary=*/false,
+ /*IsMutable=*/false, IsVolatile);
ParamDescriptors.insert({ParamOffset, {PT, Desc}});
ParamOffsets.push_back(ParamOffset);
ParamOffset += align(primSize(PT));
diff --git a/clang/lib/AST/ByteCode/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index 8aaefc7..21af3d6 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -889,6 +889,8 @@
return false;
if (!CheckConst(S, OpPC, Ptr))
return false;
+ if (!CheckVolatile(S, OpPC, Ptr, AK_Assign))
+ return false;
if (!S.inConstantContext() && isConstexprUnknown(Ptr))
return false;
return true;
diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h
index 7867a06..bb0c458 100644
--- a/clang/lib/AST/ByteCode/Interp.h
+++ b/clang/lib/AST/ByteCode/Interp.h
@@ -1730,9 +1730,8 @@
}
inline bool GetPtrParam(InterpState &S, CodePtr OpPC, uint32_t I) {
- if (S.checkingPotentialConstantExpression()) {
+ if (S.Current->isBottomFrame())
return false;
- }
S.Stk.push<Pointer>(S.Current->getParamPointer(I));
return true;
}
@@ -3344,6 +3343,18 @@
return false;
}
+inline bool InvalidStore(InterpState &S, CodePtr OpPC, const Type *T) {
+ if (S.getLangOpts().CPlusPlus) {
+ QualType VolatileType = QualType(T, 0).withVolatile();
+ S.FFDiag(S.Current->getSource(OpPC),
+ diag::note_constexpr_access_volatile_type)
+ << AK_Assign << VolatileType;
+ } else {
+ S.FFDiag(S.Current->getSource(OpPC));
+ }
+ return false;
+}
+
inline bool InvalidDeclRef(InterpState &S, CodePtr OpPC, const DeclRefExpr *DR,
bool InitializerFailed) {
assert(DR);
diff --git a/clang/lib/AST/ByteCode/InterpFrame.cpp b/clang/lib/AST/ByteCode/InterpFrame.cpp
index a3db0d7..039acb5 100644
--- a/clang/lib/AST/ByteCode/InterpFrame.cpp
+++ b/clang/lib/AST/ByteCode/InterpFrame.cpp
@@ -231,6 +231,8 @@
if (auto Pt = Params.find(Off); Pt != Params.end())
return Pointer(reinterpret_cast<Block *>(Pt->second.get()));
+ assert(!isBottomFrame());
+
// Allocate memory to store the parameter and the block metadata.
const auto &Desc = Func->getParamDescriptor(Off);
size_t BlockSize = sizeof(Block) + Desc.second->getAllocSize();
diff --git a/clang/lib/AST/ByteCode/Opcodes.td b/clang/lib/AST/ByteCode/Opcodes.td
index 7af2df5..532c444 100644
--- a/clang/lib/AST/ByteCode/Opcodes.td
+++ b/clang/lib/AST/ByteCode/Opcodes.td
@@ -797,6 +797,7 @@
def InvalidCast : Opcode {
let Args = [ArgCastKind, ArgBool];
}
+def InvalidStore : Opcode { let Args = [ArgTypePtr]; }
def CheckPseudoDtor : Opcode {}
def InvalidDeclRef : Opcode {
diff --git a/clang/test/AST/ByteCode/cxx23.cpp b/clang/test/AST/ByteCode/cxx23.cpp
index 72c751d..ce0a4777 100644
--- a/clang/test/AST/ByteCode/cxx23.cpp
+++ b/clang/test/AST/ByteCode/cxx23.cpp
@@ -1,8 +1,8 @@
// UNSUPPORTED: target={{.*}}-zos{{.*}}
-// RUN: %clang_cc1 -std=c++20 -fsyntax-only -fcxx-exceptions -verify=ref,ref20,all,all20 %s
-// RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -verify=ref,ref23,all,all23 %s
-// RUN: %clang_cc1 -std=c++20 -fsyntax-only -fcxx-exceptions -verify=expected20,all,all20 %s -fexperimental-new-constant-interpreter
-// RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -verify=expected23,all,all23 %s -fexperimental-new-constant-interpreter
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -fcxx-exceptions -Wno-deprecated-volatile -verify=ref,ref20,all,all20 %s
+// RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -Wno-deprecated-volatile -verify=ref,ref23,all,all23 %s
+// RUN: %clang_cc1 -std=c++20 -fsyntax-only -fcxx-exceptions -Wno-deprecated-volatile -verify=expected20,all,all20 %s -fexperimental-new-constant-interpreter
+// RUN: %clang_cc1 -std=c++23 -fsyntax-only -fcxx-exceptions -Wno-deprecated-volatile -verify=expected23,all,all23 %s -fexperimental-new-constant-interpreter
#define assert_active(F) if (!__builtin_is_within_lifetime(&F)) (1/0);
@@ -393,6 +393,59 @@
static_assert(g()); // all-error {{not an integral constant expression}} \
// all-note {{in call to}}
}
-
-
#endif
+
+namespace VolatileWrites {
+ constexpr void test1() {// all20-error {{never produces a constant expression}}
+ int k;
+ volatile int &m = k;
+ m = 10; // all20-note {{assignment to volatile-qualified type 'volatile int'}}
+ }
+
+ constexpr void test2() { // all20-error {{never produces a constant expression}}
+ volatile int k = 12;
+
+ k = 13; // all20-note {{assignment to volatile-qualified type 'volatile int'}}
+ }
+
+ constexpr void test3() { // all20-error {{never produces a constant expression}}
+ volatile int k = 12; // all20-note {{volatile object declared here}}
+
+ *((int *)&k) = 13; // all20-note {{assignment to volatile object 'k' is not allowed in a constant expression}}
+ }
+
+ constexpr void test4() { // all20-error {{never produces a constant expression}}
+ int k = 12;
+
+ *((volatile int *)&k) = 13; // all20-note {{assignment to volatile-qualified type 'volatile int' is not allowed in a constant expression}}
+ }
+
+#if __cplusplus >= 202302L
+ struct S {
+ volatile int k;
+ };
+ constexpr int test5() {
+ S s;
+ s.k = 12; // all-note {{assignment to volatile-qualified type 'volatile int' is not}}
+
+ return 0;
+ }
+ static_assert(test5() == 0); // all-error{{not an integral constant expression}} \
+ // all-note {{in call to}}
+#endif
+
+ constexpr bool test6(volatile int k) { // ref20-error {{never produces a constant expression}}
+ k = 14; // ref20-note {{assignment to volatile-qualified type 'volatile int' is not}} \
+ // all-note {{assignment to volatile-qualified type 'volatile int' is not}}
+ return true;
+ }
+ static_assert(test6(5)); // all-error {{not an integral constant expression}} \
+ // all-note {{in call to}}
+
+ constexpr bool test7(volatile int k) { // all-note {{declared here}}
+ *((int *)&k) = 13; // all-note {{assignment to volatile object 'k' is not allowed in a constant expression}}
+ return true;
+ }
+ static_assert(test7(12)); // all-error {{not an integral constant expression}} \
+ // all-note {{in call to}}
+}
diff --git a/clang/test/AST/ByteCode/invalid.cpp b/clang/test/AST/ByteCode/invalid.cpp
index affb40ea..00db274 100644
--- a/clang/test/AST/ByteCode/invalid.cpp
+++ b/clang/test/AST/ByteCode/invalid.cpp
@@ -1,5 +1,5 @@
// RUN: %clang_cc1 -fcxx-exceptions -std=c++20 -fexperimental-new-constant-interpreter -verify=expected,both %s
-// RUN: %clang_cc1 -fcxx-exceptions -std=c++20 -verify=ref,both %s
+// RUN: %clang_cc1 -fcxx-exceptions -std=c++20 -verify=ref,both %s
namespace Throw {
