Author: Timm Baeder Date: 2025-04-17T12:50:28+02:00 New Revision: 90ddb5444030b8d7cca6e91a27994e4fa9a6525d
URL: https://github.com/llvm/llvm-project/commit/90ddb5444030b8d7cca6e91a27994e4fa9a6525d DIFF: https://github.com/llvm/llvm-project/commit/90ddb5444030b8d7cca6e91a27994e4fa9a6525d.diff LOG: [clang][bytecode] Enter a non-constant context when revisiting (#136104) Otherwise, things like __builtin_is_constant_evaluated() return the wrong value. Added: Modified: clang/lib/AST/ByteCode/Compiler.cpp clang/lib/AST/ByteCode/Interp.h clang/lib/AST/ByteCode/InterpState.h clang/lib/AST/ByteCode/Opcodes.td clang/test/AST/ByteCode/builtin-constant-p.cpp Removed: ################################################################################ diff --git a/clang/lib/AST/ByteCode/Compiler.cpp b/clang/lib/AST/ByteCode/Compiler.cpp index 157e306e5cdb3..d3eabc513a9ac 100644 --- a/clang/lib/AST/ByteCode/Compiler.cpp +++ b/clang/lib/AST/ByteCode/Compiler.cpp @@ -6466,8 +6466,13 @@ bool Compiler<Emitter>::visitDeclRef(const ValueDecl *D, const Expr *E) { // In case we need to re-visit a declaration. auto revisit = [&](const VarDecl *VD) -> bool { + if (!this->emitPushCC(VD->hasConstantInitialization(), E)) + return false; auto VarState = this->visitDecl(VD, /*IsConstexprUnknown=*/true); + if (!this->emitPopCC(E)) + return false; + if (VarState.notCreated()) return true; if (!VarState) diff --git a/clang/lib/AST/ByteCode/Interp.h b/clang/lib/AST/ByteCode/Interp.h index bd58c2a88e9d9..49e2326186bf8 100644 --- a/clang/lib/AST/ByteCode/Interp.h +++ b/clang/lib/AST/ByteCode/Interp.h @@ -2848,6 +2848,15 @@ inline bool EndSpeculation(InterpState &S, CodePtr OpPC) { return true; } +inline bool PushCC(InterpState &S, CodePtr OpPC, bool Value) { + S.ConstantContextOverride = Value; + return true; +} +inline bool PopCC(InterpState &S, CodePtr OpPC) { + S.ConstantContextOverride = std::nullopt; + return true; +} + /// Do nothing and just abort execution. inline bool Error(InterpState &S, CodePtr OpPC) { return false; } diff --git a/clang/lib/AST/ByteCode/InterpState.h b/clang/lib/AST/ByteCode/InterpState.h index 74001b80d9c00..528c1a24e7b05 100644 --- a/clang/lib/AST/ByteCode/InterpState.h +++ b/clang/lib/AST/ByteCode/InterpState.h @@ -127,7 +127,6 @@ class InterpState final : public State, public SourceMapper { SourceMapper *M; /// Allocator used for dynamic allocations performed via the program. DynamicAllocator Alloc; - std::optional<bool> ConstantContextOverride; public: /// Reference to the module containing all bytecode. @@ -147,6 +146,7 @@ class InterpState final : public State, public SourceMapper { /// Things needed to do speculative execution. SmallVectorImpl<PartialDiagnosticAt> *PrevDiags = nullptr; unsigned SpeculationDepth = 0; + std::optional<bool> ConstantContextOverride; llvm::SmallVector< std::pair<const Expr *, const LifetimeExtendedTemporaryDecl *>> diff --git a/clang/lib/AST/ByteCode/Opcodes.td b/clang/lib/AST/ByteCode/Opcodes.td index 5a9079fea0846..8451e54ad0c41 100644 --- a/clang/lib/AST/ByteCode/Opcodes.td +++ b/clang/lib/AST/ByteCode/Opcodes.td @@ -872,3 +872,6 @@ def GetTypeidPtr : Opcode { let Args = [ArgTypePtr]; } def DiagTypeid : Opcode; def CheckDestruction : Opcode; + +def PushCC : Opcode { let Args = [ArgBool]; } +def PopCC : Opcode; diff --git a/clang/test/AST/ByteCode/builtin-constant-p.cpp b/clang/test/AST/ByteCode/builtin-constant-p.cpp index ed9e606ed16aa..f5b16761bfdc9 100644 --- a/clang/test/AST/ByteCode/builtin-constant-p.cpp +++ b/clang/test/AST/ByteCode/builtin-constant-p.cpp @@ -121,3 +121,11 @@ constexpr int mutate6(bool mutate) { static_assert(mutate6(false) == 11); static_assert(mutate6(true) == 21); // ref-error {{static assertion failed}} \ // ref-note {{evaluates to '10 == 21'}} + +#define fold(x) (__builtin_constant_p(x) ? (x) : (x)) +void g() { + /// f will be revisited when evaluating the static_assert, since it's + /// a local variable. But it should be visited in a non-constant context. + const float f = __builtin_is_constant_evaluated(); + static_assert(fold(f == 0.0f)); +} _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
