From da62ed6ceb12031992d863ce272bc4863505b84b Mon Sep 17 00:00:00 2001
From: =?utf8?q?Timm=20B=C3=A4der?= <tbaeder@redhat.com>
Date: Wed, 14 Sep 2022 15:03:04 +0200
Subject: [PATCH] [clang][Interp] Pass initializer when creating globals

This is dead code right now but will be used for implementing array
fillers, where we need some information from the initializer when
allocaing the Descriptors.

Differential Revision: https://reviews.llvm.org/D133856
---
 clang/lib/AST/Interp/ByteCodeExprGen.cpp | 12 ++++++++----
 clang/lib/AST/Interp/Program.cpp         | 12 +++++++-----
 clang/lib/AST/Interp/Program.h           |  8 +++++---
 3 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/clang/lib/AST/Interp/ByteCodeExprGen.cpp b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
index 0abd3ff..f86a7b1 100644
--- a/clang/lib/AST/Interp/ByteCodeExprGen.cpp
+++ b/clang/lib/AST/Interp/ByteCodeExprGen.cpp
@@ -513,18 +513,22 @@ ByteCodeExprGen<Emitter>::allocateLocal(DeclTy &&Src, bool IsExtended) {
   QualType Ty;
 
   const ValueDecl *Key = nullptr;
+  const Expr *Init = nullptr;
   bool IsTemporary = false;
-  if (auto *VD = dyn_cast_or_null<ValueDecl>(Src.dyn_cast<const Decl *>())) {
+  if (auto *VD = dyn_cast_if_present<ValueDecl>(Src.dyn_cast<const Decl *>())) {
     Key = VD;
     Ty = VD->getType();
+
+    if (const auto *VarD = dyn_cast<VarDecl>(VD))
+      Init = VarD->getInit();
   }
   if (auto *E = Src.dyn_cast<const Expr *>()) {
     IsTemporary = true;
     Ty = E->getType();
   }
 
-  Descriptor *D = P.createDescriptor(Src, Ty.getTypePtr(),
-                                     Ty.isConstQualified(), IsTemporary);
+  Descriptor *D = P.createDescriptor(
+      Src, Ty.getTypePtr(), Ty.isConstQualified(), IsTemporary, false, Init);
   if (!D)
     return {};
 
@@ -657,7 +661,7 @@ template <class Emitter>
 bool ByteCodeExprGen<Emitter>::visitDecl(const VarDecl *VD) {
   const Expr *Init = VD->getInit();
 
-  if (Optional<unsigned> I = P.createGlobal(VD)) {
+  if (Optional<unsigned> I = P.createGlobal(VD, Init)) {
     if (Optional<PrimType> T = classify(VD->getType())) {
       {
         // Primitive declarations - compute the value and set it.
diff --git a/clang/lib/AST/Interp/Program.cpp b/clang/lib/AST/Interp/Program.cpp
index 0d4d84e..aa700a1 100644
--- a/clang/lib/AST/Interp/Program.cpp
+++ b/clang/lib/AST/Interp/Program.cpp
@@ -127,7 +127,7 @@ llvm::Optional<unsigned> Program::getOrCreateGlobal(const ValueDecl *VD) {
   if (auto Idx = getGlobal(VD))
     return Idx;
 
-  if (auto Idx = createGlobal(VD)) {
+  if (auto Idx = createGlobal(VD, nullptr)) {
     GlobalIndices[VD] = *Idx;
     return Idx;
   }
@@ -153,7 +153,8 @@ llvm::Optional<unsigned> Program::getOrCreateDummy(const ParmVarDecl *PD) {
   return {};
 }
 
-llvm::Optional<unsigned> Program::createGlobal(const ValueDecl *VD) {
+llvm::Optional<unsigned> Program::createGlobal(const ValueDecl *VD,
+                                               const Expr *Init) {
   bool IsStatic, IsExtern;
   if (auto *Var = dyn_cast<VarDecl>(VD)) {
     IsStatic = !Var->hasLocalStorage();
@@ -162,7 +163,7 @@ llvm::Optional<unsigned> Program::createGlobal(const ValueDecl *VD) {
     IsStatic = false;
     IsExtern = true;
   }
-  if (auto Idx = createGlobal(VD, VD->getType(), IsStatic, IsExtern)) {
+  if (auto Idx = createGlobal(VD, VD->getType(), IsStatic, IsExtern, Init)) {
     for (const Decl *P = VD; P; P = P->getPreviousDecl())
       GlobalIndices[P] = *Idx;
     return *Idx;
@@ -175,7 +176,8 @@ llvm::Optional<unsigned> Program::createGlobal(const Expr *E) {
 }
 
 llvm::Optional<unsigned> Program::createGlobal(const DeclTy &D, QualType Ty,
-                                               bool IsStatic, bool IsExtern) {
+                                               bool IsStatic, bool IsExtern,
+                                               const Expr *Init) {
   // Create a descriptor for the global.
   Descriptor *Desc;
   const bool IsConst = Ty.isConstQualified();
@@ -310,7 +312,7 @@ Record *Program::getOrCreateRecord(const RecordDecl *RD) {
 
 Descriptor *Program::createDescriptor(const DeclTy &D, const Type *Ty,
                                       bool IsConst, bool IsTemporary,
-                                      bool IsMutable) {
+                                      bool IsMutable, const Expr *Init) {
   // Classes and structures.
   if (auto *RT = Ty->getAs<RecordType>()) {
     if (auto *Record = getOrCreateRecord(RT->getDecl()))
diff --git a/clang/lib/AST/Interp/Program.h b/clang/lib/AST/Interp/Program.h
index ca985af..b711bd2 100644
--- a/clang/lib/AST/Interp/Program.h
+++ b/clang/lib/AST/Interp/Program.h
@@ -69,7 +69,7 @@ public:
   llvm::Optional<unsigned> getOrCreateDummy(const ParmVarDecl *PD);
 
   /// Creates a global and returns its index.
-  llvm::Optional<unsigned> createGlobal(const ValueDecl *VD);
+  llvm::Optional<unsigned> createGlobal(const ValueDecl *VD, const Expr *E);
 
   /// Creates a global from a lifetime-extended temporary.
   llvm::Optional<unsigned> createGlobal(const Expr *E);
@@ -111,7 +111,8 @@ public:
   /// Creates a descriptor for a composite type.
   Descriptor *createDescriptor(const DeclTy &D, const Type *Ty,
                                bool IsConst = false, bool IsTemporary = false,
-                               bool IsMutable = false);
+                               bool IsMutable = false,
+                               const Expr *Init = nullptr);
 
   /// Context to manage declaration lifetimes.
   class DeclScope {
@@ -134,7 +135,8 @@ private:
   friend class DeclScope;
 
   llvm::Optional<unsigned> createGlobal(const DeclTy &D, QualType Ty,
-                                        bool IsStatic, bool IsExtern);
+                                        bool IsStatic, bool IsExtern,
+                                        const Expr *Init = nullptr);
 
   /// Reference to the VM context.
   Context &Ctx;
-- 
2.7.4