clang 19.0.0git
InterpState.cpp
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1//===--- InterpState.cpp - Interpreter for the constexpr VM -----*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "InterpState.h"
10#include "InterpFrame.h"
11#include "InterpStack.h"
12#include "Program.h"
13#include "State.h"
14
15using namespace clang;
16using namespace clang::interp;
17
19 Context &Ctx, SourceMapper *M)
20 : Parent(Parent), M(M), P(P), Stk(Stk), Ctx(Ctx), Current(nullptr) {}
21
23 while (Current) {
24 InterpFrame *Next = Current->Caller;
25 delete Current;
26 Current = Next;
27 }
28
29 while (DeadBlocks) {
30 DeadBlock *Next = DeadBlocks->Next;
31 std::free(DeadBlocks);
32 DeadBlocks = Next;
33 }
34}
35
37
39 if (Current && Current->Caller)
40 return Current;
41 return Parent.getCurrentFrame();
42}
43
44bool InterpState::reportOverflow(const Expr *E, const llvm::APSInt &Value) {
46 CCEDiag(E, diag::note_constexpr_overflow) << Value << Type;
47 return noteUndefinedBehavior();
48}
49
51 assert(B);
52 const Descriptor *Desc = B->getDescriptor();
53 assert(Desc);
54
55 if (B->hasPointers()) {
56 size_t Size = B->getSize();
57
58 // Allocate a new block, transferring over pointers.
59 char *Memory =
60 reinterpret_cast<char *>(std::malloc(sizeof(DeadBlock) + Size));
61 auto *D = new (Memory) DeadBlock(DeadBlocks, B);
62
63 // Move data and metadata from the old block to the new (dead)block.
64 if (Desc->MoveFn) {
65 Desc->MoveFn(B, B->data(), D->data(), Desc);
66 if (Desc->getMetadataSize() > 0)
67 std::memcpy(D->rawData(), B->rawData(), Desc->getMetadataSize());
68 }
69
70 // We moved the contents over to the DeadBlock.
71 B->IsInitialized = false;
72 } else {
73 B->invokeDtor();
74 }
75}
NodeId Parent
Definition: ASTDiff.cpp:191
StringRef P
const Decl * D
Expr * E
This represents one expression.
Definition: Expr.h:110
QualType getType() const
Definition: Expr.h:142
A (possibly-)qualified type.
Definition: Type.h:942
The base class of the type hierarchy.
Definition: Type.h:1829
A memory block, either on the stack or in the heap.
Definition: InterpBlock.h:49
unsigned getSize() const
Returns the size of the block.
Definition: InterpBlock.h:77
void invokeDtor()
Invokes the Destructor.
Definition: InterpBlock.h:125
std::byte * data()
Returns a pointer to the stored data.
Definition: InterpBlock.h:88
const Descriptor * getDescriptor() const
Returns the block's descriptor.
Definition: InterpBlock.h:67
std::byte * rawData()
Returns a pointer to the raw data, including metadata.
Definition: InterpBlock.h:101
bool hasPointers() const
Checks if the block has any live pointers.
Definition: InterpBlock.h:69
Holds all information required to evaluate constexpr code in a module.
Definition: Context.h:40
Descriptor for a dead block.
Definition: InterpBlock.h:180
Base class for stack frames, shared between VM and walker.
Definition: Frame.h:25
Frame storing local variables.
Definition: InterpFrame.h:28
InterpFrame * Caller
The frame of the previous function.
Definition: InterpFrame.h:31
Stack frame storing temporaries and parameters.
Definition: InterpStack.h:27
bool reportOverflow(const Expr *E, const llvm::APSInt &Value)
Reports overflow and return true if evaluation should continue.
Definition: InterpState.cpp:44
bool noteUndefinedBehavior() override
Definition: InterpState.h:73
Frame * getCurrentFrame() override
Definition: InterpState.cpp:38
InterpFrame * Current
The current frame.
Definition: InterpState.h:121
InterpState(State &Parent, Program &P, InterpStack &Stk, Context &Ctx, SourceMapper *M=nullptr)
Definition: InterpState.cpp:18
void deallocate(Block *B)
Deallocates a pointer.
Definition: InterpState.cpp:50
The program contains and links the bytecode for all functions.
Definition: Program.h:39
Interface for classes which map locations to sources.
Definition: Source.h:94
Interface for the VM to interact with the AST walker's context.
Definition: State.h:55
virtual Frame * getCurrentFrame()=0
OptionalDiagnostic CCEDiag(SourceLocation Loc, diag::kind DiagId=diag::note_invalid_subexpr_in_const_expr, unsigned ExtraNotes=0)
Diagnose that the evaluation does not produce a C++11 core constant expression.
Definition: State.cpp:42
The JSON file list parser is used to communicate input to InstallAPI.
Describes a memory block created by an allocation site.
Definition: Descriptor.h:104
const BlockMoveFn MoveFn
Definition: Descriptor.h:150
unsigned getMetadataSize() const
Returns the size of the metadata.
Definition: Descriptor.h:222