Merge pull request #8867 from JuliaLang/sjk/tbaa

Use tbaa for heap-allocated immutables

Author: StefanKarpinski

src/cgutils.cpp

@@ -865,7 +865,7 @@ static Value *emit_nthptr_recast(Value *v, size_t n, MDNode *tbaa, Type* ptype)
 static Value *ghostValue(jl_value_t *ty);
 
 static Value *typed_load(Value *ptr, Value *idx_0based, jl_value_t *jltype,
-                         jl_codectx_t *ctx)
+                         jl_codectx_t *ctx, MDNode* tbaa)
 {
     Type *elty = julia_type_to_llvm(jltype);
     assert(elty != NULL);
@@ -878,7 +878,7 @@ static Value *typed_load(Value *ptr, Value *idx_0based, jl_value_t *jltype,
         data = builder.CreateBitCast(ptr, PointerType::get(elty, 0));
     else
         data = ptr;
-    Value *elt = tbaa_decorate(tbaa_user, builder.CreateLoad(builder.CreateGEP(data, idx_0based), false));
+    Value *elt = tbaa_decorate(tbaa, builder.CreateLoad(builder.CreateGEP(data, idx_0based), false));
     if (elty == jl_pvalue_llvmt) {
         null_pointer_check(elt, ctx);
     }
@@ -890,7 +890,7 @@ static Value *typed_load(Value *ptr, Value *idx_0based, jl_value_t *jltype,
 static Value *emit_unbox(Type *to, Value *x, jl_value_t *jt);
 
 static void typed_store(Value *ptr, Value *idx_0based, Value *rhs,
-                        jl_value_t *jltype, jl_codectx_t *ctx)
+                        jl_value_t *jltype, jl_codectx_t *ctx, MDNode* tbaa)
 {
     Type *elty = julia_type_to_llvm(jltype);
     assert(elty != NULL);
@@ -906,7 +906,7 @@ static void typed_store(Value *ptr, Value *idx_0based, Value *rhs,
         data = builder.CreateBitCast(ptr, PointerType::get(elty, 0));
     else
         data = ptr;
-    tbaa_decorate(tbaa_user, builder.CreateStore(rhs, builder.CreateGEP(data, idx_0based)));
+    tbaa_decorate(tbaa, builder.CreateStore(rhs, builder.CreateGEP(data, idx_0based)));
 }
 
 // --- convert boolean value to julia ---

src/codegen.cpp

@@ -240,6 +240,7 @@ static Type *T_void;
 // type-based alias analysis nodes.  Indentation of comments indicates hierarchy.
 static MDNode* tbaa_user;           // User data
 static MDNode* tbaa_value;          // Julia value
+static MDNode* tbaa_immut;          // Data inside a heap-allocated immutable
 static MDNode* tbaa_array;              // Julia array
 static MDNode* tbaa_arrayptr;               // The pointer inside a jl_array_t
 static MDNode* tbaa_arraysize;              // A size in a jl_array_t
@@ -1487,13 +1488,14 @@ static Value *emit_getfield(jl_value_t *expr, jl_sym_t *name, jl_codectx_t *ctx)
                                       ConstantInt::get(T_size,
                                                        sty->fields[idx].offset + sizeof(void*)));
                 JL_GC_POP();
+                MDNode *tbaa = sty->mutabl ? tbaa_user : tbaa_immut;
                 if (sty->fields[idx].isptr) {
-                    Value *fldv = builder.CreateLoad(builder.CreateBitCast(addr,jl_ppvalue_llvmt));
+                    Value *fldv = tbaa_decorate(tbaa, builder.CreateLoad(builder.CreateBitCast(addr,jl_ppvalue_llvmt)));
                     null_pointer_check(fldv, ctx);
                     return fldv;
                 }
                 else {
-                    return typed_load(addr, ConstantInt::get(T_size, 0), jfty, ctx);
+                    return typed_load(addr, ConstantInt::get(T_size, 0), jfty, ctx, tbaa);
                 }
             }
             else {
@@ -1551,7 +1553,7 @@ static void emit_setfield(jl_datatype_t *sty, Value *strct, size_t idx,
                                 builder.CreateBitCast(addr, jl_ppvalue_llvmt));
         }
         else {
-            typed_store(addr, ConstantInt::get(T_size, 0), rhs, jfty, ctx);
+            typed_store(addr, ConstantInt::get(T_size, 0), rhs, jfty, ctx, sty->mutabl ? tbaa_user : tbaa_immut);
         }
     }
     else {
@@ -2064,7 +2066,7 @@ static Value *emit_known_call(jl_value_t *ff, jl_value_t **args, size_t nargs,
                         assert(((jl_datatype_t*)ety)->instance != NULL);
                         return literal_pointer_val(((jl_datatype_t*)ety)->instance);
                     }
-                    return typed_load(emit_arrayptr(ary, args[1], ctx), idx, ety, ctx);
+                    return typed_load(emit_arrayptr(ary, args[1], ctx), idx, ety, ctx, tbaa_user);
                 }
             }
         }
@@ -2097,7 +2099,7 @@ static Value *emit_known_call(jl_value_t *ff, jl_value_t **args, size_t nargs,
                     else {
                         typed_store(emit_arrayptr(ary,args[1],ctx), idx,
                                     ety==(jl_value_t*)jl_any_type ? emit_expr(args[2],ctx) : emit_unboxed(args[2],ctx),
-                                    ety, ctx);
+                                    ety, ctx, tbaa_user);
                     }
                     JL_GC_POP();
                     return ary;
@@ -2152,7 +2154,7 @@ static Value *emit_known_call(jl_value_t *ff, jl_value_t **args, size_t nargs,
                         idx = emit_bounds_check(idx, ConstantInt::get(T_size, nfields), ctx);
                         Value *ptr = data_pointer(strct);
                         JL_GC_POP();
-                        return typed_load(ptr, idx, jt, ctx);
+                        return typed_load(ptr, idx, jt, ctx, stt->mutabl ? tbaa_user : tbaa_immut);
                     }
                     else {
                         idx = builder.CreateSub(idx, ConstantInt::get(T_size, 1));
@@ -2179,7 +2181,7 @@ static Value *emit_known_call(jl_value_t *ff, jl_value_t **args, size_t nargs,
                         jl_value_t *jt = jl_t0(stt->types);
                         idx = emit_bounds_check(idx, ConstantInt::get(T_size, nfields), ctx);
                         Value *ptr = builder.CreateGEP(tempSpace, ConstantInt::get(T_size, 0));
-                        fld = typed_load(ptr, idx, jt, ctx);
+                        fld = typed_load(ptr, idx, jt, ctx, stt->mutabl ? tbaa_user : tbaa_immut);
                         builder.CreateCall(Intrinsic::getDeclaration(jl_Module,Intrinsic::stackrestore),
                                            stacksave);
                     }
@@ -4188,6 +4190,7 @@ static void init_julia_llvm_env(Module *m)
     MDNode* tbaa_root = mbuilder->createTBAARoot("jtbaa");
     tbaa_user = tbaa_make_child("jtbaa_user",tbaa_root);
     tbaa_value = tbaa_make_child("jtbaa_value",tbaa_root);
+    tbaa_immut = tbaa_make_child("jtbaa_immut",tbaa_root);
     tbaa_array = tbaa_make_child("jtbaa_array",tbaa_value);
     tbaa_arrayptr = tbaa_make_child("jtbaa_arrayptr",tbaa_array);
     tbaa_arraysize = tbaa_make_child("jtbaa_arraysize",tbaa_array);

src/intrinsics.cpp

@@ -744,7 +744,7 @@ static Value *emit_pointerref(jl_value_t *e, jl_value_t *i, jl_codectx_t *ctx)
                             thePtr, size, 1);
         return mark_julia_type(strct, ety);
     }
-    return typed_load(thePtr, im1, ety, ctx);
+    return typed_load(thePtr, im1, ety, ctx, tbaa_user);
 }
 
 static Value *emit_runtime_pointerset(jl_value_t *e, jl_value_t *x, jl_value_t *i, jl_codectx_t *ctx)
@@ -803,7 +803,7 @@ static Value *emit_pointerset(jl_value_t *e, jl_value_t *x, jl_value_t *i, jl_co
             else
                 val = emit_unboxed(x,ctx);
         }
-        typed_store(thePtr, im1, val, ety, ctx);
+        typed_store(thePtr, im1, val, ety, ctx, tbaa_user);
     }
     return mark_julia_type(thePtr, aty);
 }