Frontend: Get rid of unused backend-reserved Symbol

Somewhat reducing memory requirements by stripping the unused fields too.

dmd/aggregate.d

@@ -829,9 +829,12 @@ extern (C++) abstract class AggregateDeclaration : ScopeDsymbol
         return type;
     }
 
+version (IN_LLVM) {} else
+{
     // Back end
     Symbol* stag; // tag symbol for debug data
     Symbol* sinit;
+}
 
     override final inout(AggregateDeclaration) isAggregateDeclaration() inout
     {

dmd/aggregate.h

@@ -138,9 +138,11 @@ public:
     // 'this' type
     Type *handleType() { return type; }
 
+#if !IN_LLVM
     // Back end
     Symbol *stag;               // tag symbol for debug data
     Symbol *sinit;
+#endif
 
     AggregateDeclaration *isAggregateDeclaration() { return this; }
     void accept(Visitor *v) { v->visit(this); }
@@ -279,7 +281,9 @@ public:
     Abstract isabstract;                // 0: fwdref, 1: is abstract class, 2: not abstract
     Baseok baseok;                      // set the progress of base classes resolving
     ObjcClassDeclaration objc;          // Data for a class declaration that is needed for the Objective-C integration
+#if !IN_LLVM
     Symbol *cpp_type_info_ptr_sym;      // cached instance of class Id.cpp_type_info_ptr
+#endif
 
     static ClassDeclaration *create(Loc loc, Identifier *id, BaseClasses *baseclasses, Dsymbols *members, bool inObject);
     Dsymbol *syntaxCopy(Dsymbol *s);

dmd/dclass.d

@@ -223,7 +223,10 @@ extern (C++) class ClassDeclaration : AggregateDeclaration
      */
     ObjcClassDeclaration objc;
 
+version (IN_LLVM) {} else
+{
     Symbol* cpp_type_info_ptr_sym;      // cached instance of class Id.cpp_type_info_ptr
+}
 
     final extern (D) this(const ref Loc loc, Identifier id, BaseClasses* baseclasses, Dsymbols* members, bool inObject)
     {

dmd/declaration.h

@@ -543,7 +543,9 @@ public:
     // Support for NRVO (named return value optimization)
     bool nrvo_can;                      // true means we can do it
     VarDeclaration *nrvo_var;           // variable to replace with shidden
+#if !IN_LLVM
     Symbol *shidden;                    // hidden pointer passed to function
+#endif
 
     ReturnStatements *returns;
 

dmd/denum.d

@@ -360,7 +360,10 @@ extern (C++) final class EnumDeclaration : ScopeDsymbol
         return this;
     }
 
+version (IN_LLVM) {} else
+{
     Symbol* sinit;
+}
 
     override void accept(Visitor v)
     {

dmd/dmodule.d

@@ -1491,17 +1491,6 @@ else
     }
 
     // Back end
-    int doppelganger; // sub-module
-    Symbol* cov; // private uint[] __coverage;
-    uint* covb; // bit array of valid code line numbers
-    Symbol* sictor; // module order independent constructor
-    Symbol* sctor; // module constructor
-    Symbol* sdtor; // module destructor
-    Symbol* ssharedctor; // module shared constructor
-    Symbol* sshareddtor; // module shared destructor
-    Symbol* stest; // module unit test
-    Symbol* sfilename; // symbol for filename
-
 version (IN_LLVM)
 {
     //llvm::Module* genLLVMModule(llvm::LLVMContext& context);
@@ -1516,6 +1505,19 @@ version (IN_LLVM)
     void* d_cover_data;   // llvm::GlobalVariable* --> private uint[] _d_cover_data;
     Array!size_t d_cover_valid_init; // initializer for _d_cover_valid
 }
+else
+{
+    int doppelganger; // sub-module
+    Symbol* cov; // private uint[] __coverage;
+    uint* covb; // bit array of valid code line numbers
+    Symbol* sictor; // module order independent constructor
+    Symbol* sctor; // module constructor
+    Symbol* sdtor; // module destructor
+    Symbol* ssharedctor; // module shared constructor
+    Symbol* sshareddtor; // module shared destructor
+    Symbol* stest; // module unit test
+    Symbol* sfilename; // symbol for filename
+}
 
     override inout(Module) isModule() inout
     {

dmd/dsymbol.d

@@ -235,8 +235,16 @@ extern (C++) class Dsymbol : ASTNode
     Dsymbol parent;
     /// C++ namespace this symbol belongs to
     CPPNamespaceDeclaration cppnamespace;
+version (IN_LLVM)
+{
+    void* ir; // IrDsymbol*
+    uint llvmInternal;
+}
+else
+{
     Symbol* csym;           // symbol for code generator
     Symbol* isym;           // import version of csym
+}
     const(char)* comment;   // documentation comment for this Dsymbol
     const Loc loc;          // where defined
     Scope* _scope;          // !=null means context to use for semantic()
@@ -251,14 +259,6 @@ extern (C++) class Dsymbol : ASTNode
     // (only use this with ddoc)
     UnitTestDeclaration ddocUnittest;
 
-version (IN_LLVM)
-{
-    // llvm stuff
-    uint llvmInternal;
-
-    void* ir; // IrDsymbol*
-}
-
     final extern (D) this()
     {
         //printf("Dsymbol::Dsymbol(%p)\n", this);

dmd/dsymbol.h

@@ -82,7 +82,7 @@ class OverloadSet;
 struct AA;
 #ifdef IN_GCC
 typedef union tree_node Symbol;
-#else
+#elif !IN_LLVM
 struct Symbol;
 #endif
 
@@ -157,8 +157,13 @@ public:
     Dsymbol *parent;
     /// C++ namespace this symbol belongs to
     CPPNamespaceDeclaration *namespace_;
+#if IN_LLVM
+    IrDsymbol *ir;
+    uint32_t llvmInternal;
+#else
     Symbol *csym;               // symbol for code generator
     Symbol *isym;               // import version of csym
+#endif
     const utf8_t *comment;       // documentation comment for this Dsymbol
     Loc loc;                    // where defined
     Scope *_scope;               // !=NULL means context to use for semantic()
@@ -169,13 +174,6 @@ public:
     UserAttributeDeclaration *userAttribDecl;   // user defined attributes
     UnitTestDeclaration *ddocUnittest; // !=NULL means there's a ddoc unittest associated with this symbol (only use this with ddoc)
 
-#if IN_LLVM
-    // llvm stuff
-    uint32_t llvmInternal;
-
-    IrDsymbol *ir;
-#endif
-
     static Dsymbol *create(Identifier *);
     const char *toChars() const;
     virtual const char *toPrettyCharsHelper(); // helper to print fully qualified (template) arguments

dmd/enum.h

@@ -56,7 +56,9 @@ public:
 
     EnumDeclaration *isEnumDeclaration() { return this; }
 
+#if !IN_LLVM
     Symbol *sinit;
+#endif
     void accept(Visitor *v) { v->visit(this); }
 };
 

dmd/expression.d

@@ -3056,8 +3056,10 @@ version (IN_LLVM)
     // to the memory used to build the literal for resolving such references.
     void* inProgressMemory; // llvm::Value*
 }
-
+else
+{
     Symbol* sym;            /// back end symbol to initialize with literal
+}
 
     /** pointer to the origin instance of the expression.
      * once a new expression is created, origin is set to 'this'.

dmd/expression.h

@@ -41,7 +41,7 @@ class StringExp;
 struct UnionExp;
 #ifdef IN_GCC
 typedef union tree_node Symbol;
-#else
+#elif !IN_LLVM
 struct Symbol;          // back end symbol
 #endif
 
@@ -463,9 +463,9 @@ public:
     // now contain pointers to themselves. While in toElem, contains a pointer
     // to the memory used to build the literal for resolving such references.
     llvm::Value *inProgressMemory;
-#endif
-
+#else
     Symbol *sym;        // back end symbol to initialize with literal
+#endif
 
     /** pointer to the origin instance of the expression.
      * once a new expression is created, origin is set to 'this'.

dmd/func.d

@@ -296,7 +296,10 @@ version (IN_LLVM)
     // Support for NRVO (named return value optimization)
     bool nrvo_can = true;               /// true means we can do NRVO
     VarDeclaration nrvo_var;            /// variable to replace with shidden
+version (IN_LLVM) {} else
+{
     Symbol* shidden;                    /// hidden pointer passed to function
+}
 
     ReturnStatements* returns;
 

dmd/gluelayer.d

@@ -22,7 +22,6 @@ import dmd.root.file;
 
 version (IN_LLVM)
 {
-    struct Symbol;
     struct code;
     struct block;
     struct Blockx;

dmd/inline.d

@@ -663,8 +663,11 @@ public:
                 auto vto = new VarDeclaration(vd.loc, vd.type, vd.ident, vd._init);
                 memcpy(cast(void*)vto, cast(void*)vd, __traits(classInstanceSize, VarDeclaration));
                 vto.parent = ids.parent;
+version (IN_LLVM) {} else
+{
                 vto.csym = null;
                 vto.isym = null;
+}
 
                 ids.from.push(vd);
                 ids.to.push(vto);
@@ -817,8 +820,11 @@ public:
                 auto vto = new VarDeclaration(vd.loc, vd.type, vd.ident, vd._init);
                 memcpy(cast(void*)vto, cast(void*)vd, __traits(classInstanceSize, VarDeclaration));
                 vto.parent = ids.parent;
+version (IN_LLVM) {} else
+{
                 vto.csym = null;
                 vto.isym = null;
+}
 
                 ids.from.push(vd);
                 ids.to.push(vto);
@@ -846,8 +852,11 @@ public:
                 auto vto = new VarDeclaration(vd.loc, vd.type, vd.ident, vd._init);
                 memcpy(cast(void*)vto, cast(void*)vd, __traits(classInstanceSize, VarDeclaration));
                 vto.parent = ids.parent;
+version (IN_LLVM) {} else
+{
                 vto.csym = null;
                 vto.isym = null;
+}
 
                 ids.from.push(vd);
                 ids.to.push(vto);

dmd/module.h

@@ -147,6 +147,20 @@ public:
 
     // Back end
 
+#if IN_LLVM
+    llvm::Module *genLLVMModule(llvm::LLVMContext &context);
+    void checkAndAddOutputFile(const FileName &file);
+    void makeObjectFilenameUnique();
+
+    bool llvmForceLogging;
+    bool noModuleInfo; /// Do not emit any module metadata.
+
+    // Coverage analysis
+    llvm::GlobalVariable
+        *d_cover_valid; // private immutable size_t[] _d_cover_valid;
+    llvm::GlobalVariable *d_cover_data; // private uint[] _d_cover_data;
+    Array<size_t> d_cover_valid_init;   // initializer for _d_cover_valid
+#else
     int doppelganger;           // sub-module
     Symbol *cov;                // private uint[] __coverage;
     unsigned *covb;             // bit array of valid code line numbers
@@ -159,20 +173,6 @@ public:
     Symbol *stest;              // module unit test
 
     Symbol *sfilename;          // symbol for filename
-
-#if IN_LLVM
-    // LDC
-    llvm::Module* genLLVMModule(llvm::LLVMContext& context);
-    void checkAndAddOutputFile(const FileName &file);
-    void makeObjectFilenameUnique();
-
-    bool llvmForceLogging;
-    bool noModuleInfo; /// Do not emit any module metadata.
-
-    // Coverage analysis
-    llvm::GlobalVariable* d_cover_valid;  // private immutable size_t[] _d_cover_valid;
-    llvm::GlobalVariable* d_cover_data;   // private uint[] _d_cover_data;
-    Array<size_t>         d_cover_valid_init; // initializer for _d_cover_valid
 #endif
 
     Module *isModule() { return this; }

gen/toir.cpp

@@ -2924,14 +2924,3 @@ bool toInPlaceConstruction(DLValue *lhs, Expression *rhs) {
 
   return false;
 }
-
-////////////////////////////////////////////////////////////////////////////////
-
-// FIXME: Implement & place in right module
-Symbol *toModuleAssert(Module *m) { return nullptr; }
-
-// FIXME: Implement & place in right module
-Symbol *toModuleUnittest(Module *m) { return nullptr; }
-
-// FIXME: Implement & place in right module
-Symbol *toModuleArray(Module *m) { return nullptr; }