[clang][bytecode] Diagnose volatile writes #160350
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
llvmbot
added
clang
Member
|
@llvm/pr-subscribers-clang Author: Timm Baeder (tbaederr) ChangesFull diff: https://github.com/llvm/llvm-project/pull/160350.diff 7 Files Affected:
diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp
index b4da99957ee88..a81107289d91d 100644
--- a/clang/lib/AST/ByteCode/Compiler.cpp
+++ b/clang/lib/AST/ByteCode/Compiler.cpp
@@ -4452,6 +4452,9 @@ bool Compiler<Emitter>::visitAssignment(const Expr *LHS, const Expr *RHS,
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 +4563,14 @@ bool Compiler<Emitter>::emitConst(const APSInt &Value, const Expr *E) {
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 +4878,8 @@ Compiler<Emitter>::visitVarDecl(const VarDecl *VD, const Expr *Init,
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 09599b3547888..5c46f75af4da3 100644
--- a/clang/lib/AST/ByteCode/Compiler.h
+++ b/clang/lib/AST/ByteCode/Compiler.h
@@ -327,6 +327,7 @@ class Compiler : public ConstStmtVisitor<Compiler<Emitter>, bool>,
/// 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/Interp.cpp b/clang/lib/AST/ByteCode/Interp.cpp
index 0f322f6ed42ac..6a737c1c5e550 100644
--- a/clang/lib/AST/ByteCode/Interp.cpp
+++ b/clang/lib/AST/ByteCode/Interp.cpp
@@ -889,6 +889,8 @@ bool CheckStore(InterpState &S, CodePtr OpPC, const Pointer &Ptr) {
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 b3b4b998439cc..d98ae8853147e 100644
--- a/clang/lib/AST/ByteCode/Interp.h
+++ b/clang/lib/AST/ByteCode/Interp.h
@@ -3344,6 +3344,19 @@ inline bool InvalidCast(InterpState &S, CodePtr OpPC, CastKind Kind,
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/Opcodes.td b/clang/lib/AST/ByteCode/Opcodes.td
index 7af2df5318106..532c4448e6f40 100644
--- a/clang/lib/AST/ByteCode/Opcodes.td
+++ b/clang/lib/AST/ByteCode/Opcodes.td
@@ -797,6 +797,7 @@ def SideEffect : Opcode {}
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 72c751d627a44..0cc6e3b25fcef 100644
--- a/clang/test/AST/ByteCode/cxx23.cpp
+++ b/clang/test/AST/ByteCode/cxx23.cpp
@@ -393,6 +393,48 @@ namespace UnionMemberCallDiags {
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; // all20-note {{volatile object declared here}}
+
+ *((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
+}
diff --git a/clang/test/AST/ByteCode/invalid.cpp b/clang/test/AST/ByteCode/invalid.cpp
index affb40eada870..00db27419e36b 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 {
|
tbaederr
force-pushed
the
volatile-writes
branch
2 times, most recently
from
9b7c1aa to
1cd424c
Compare
|
✅ With the latest revision this PR passed the C/C++ code formatter. |
tbaederr
force-pushed
the
volatile-writes
branch
2 times, most recently
from
ed58b80 to
c950c3d
Compare
tbaederr
force-pushed
the
volatile-writes
branch
from
c950c3d to
4eaebc3
Compare
Collaborator
|
LLVM Buildbot has detected a new failure on builder Full details are available at: https://lab.llvm.org/buildbot/#/builders/141/builds/11859 Here is the relevant piece of the build log for the reference |
mahesh-attarde
pushed a commit
to mahesh-attarde/llvm-project
that referenced
this pull request
Oct 3, 2025
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
3 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
No description provided.