config.h added
[libfirm] / ir / be / beabi.c
index 2cd8dec..97db03e 100644 (file)
@@ -32,14 +32,31 @@ typedef struct _be_abi_call_arg_t {
 
        int pos;
        const arch_register_t *reg;
+       entity *stack_ent;
 } be_abi_call_arg_t;
 
 struct _be_abi_call_t {
        be_abi_call_flags_t flags;
-       unsigned arg_gap;
+       type *between_type;
        set *params;
 };
 
+typedef struct _be_stack_frame_t {
+       type *arg_type;
+       type *between_type;
+       type *frame_type;
+
+       type *order[3];        /**< arg, between and frame types ordered. */
+
+       int initial_offset;
+       int stack_dir;
+} be_stack_frame_t;
+
+struct _be_stack_slot_t {
+       struct _be_stack_frame_t *frame;
+       entity *ent;
+};
+
 struct _be_abi_irg_t {
        struct obstack      obst;
        be_irg_t            *birg;
@@ -59,6 +76,10 @@ struct _be_abi_irg_t {
        unsigned omit_fp : 1;
        unsigned dedicated_fp : 1;
        unsigned left_to_right : 1;
+       unsigned save_old_fp : 1;
+
+       ir_node *store_bp_mem;
+       be_stack_frame_t *frame;
 
        firm_dbg_module_t *dbg;            /**< The debugging module. */
 };
@@ -89,10 +110,10 @@ static INLINE be_abi_call_arg_t *get_call_arg(be_abi_call_t *call, int is_res, i
        return get_or_set_call_arg(call, is_res, pos, 0);
 }
 
-void be_abi_call_set_flags(be_abi_call_t *call, be_abi_call_flags_t flags, unsigned arg_gap)
+void be_abi_call_set_flags(be_abi_call_t *call, be_abi_call_flags_t flags, ir_type *between_type)
 {
-       call->flags   = flags;
-       call->arg_gap = arg_gap;
+       call->flags            = flags;
+       call->between_type     = between_type;
 }
 
 void be_abi_call_param_stack(be_abi_call_t *call, int arg_pos)
@@ -103,12 +124,14 @@ void be_abi_call_param_stack(be_abi_call_t *call, int arg_pos)
 void be_abi_call_param_reg(be_abi_call_t *call, int arg_pos, const arch_register_t *reg)
 {
        be_abi_call_arg_t *arg = get_or_set_call_arg(call, 0, arg_pos, 1);
+       arg->in_reg = 1;
        arg->reg = reg;
 }
 
 void be_abi_call_res_reg(be_abi_call_t *call, int arg_pos, const arch_register_t *reg)
 {
        be_abi_call_arg_t *arg = get_or_set_call_arg(call, 1, arg_pos, 1);
+       arg->in_reg = 1;
        arg->reg = reg;
 }
 
@@ -126,6 +149,113 @@ void be_abi_call_free(be_abi_call_t *call)
        free(call);
 }
 
+static int get_stack_entity_offset(be_stack_frame_t *frame, entity *ent, int bias)
+{
+       type *t = get_entity_type(ent);
+       int ofs = get_entity_offset_bytes(ent);
+
+       int i, index;
+
+       /* Find the type the entity is contained in. */
+       for(index = 0; index < 3; ++index) {
+               if(frame->order[index] == t)
+                       break;
+       }
+
+       /* Add the size of all the types below the one of the entity to the entity's offset */
+       for(i = 0; i < index; ++i)
+               ofs += get_type_size_bytes(frame->order[i]);
+
+       /* correct the offset by the initial position of the frame pointer */
+       ofs -= frame->initial_offset;
+
+       /* correct the offset with the current bias. */
+       ofs += bias;
+
+       return ofs;
+}
+
+static int stack_frame_compute_initial_offset(be_stack_frame_t *frame, entity *ent)
+{
+       frame->initial_offset = 0;
+       frame->initial_offset = get_stack_entity_offset(frame, ent, 0);
+       return frame->initial_offset;
+}
+
+static be_stack_frame_t *stack_frame_init(be_stack_frame_t *frame, type *args, type *between, type *locals, int stack_dir)
+{
+       frame->arg_type       = args;
+       frame->between_type   = between;
+       frame->frame_type     = locals;
+       frame->initial_offset = 0;
+       frame->stack_dir      = stack_dir;
+       frame->order[1]       = between;
+
+       if(stack_dir > 0) {
+               frame->order[0] = args;
+               frame->order[2] = locals;
+       }
+
+       else {
+               frame->order[0] = locals;
+               frame->order[2] = args;
+       }
+
+       return frame;
+}
+
+static INLINE entity *get_sel_ent(ir_node *irn)
+{
+       if(get_irn_opcode(irn) == iro_Sel
+               && get_Sel_ptr(irn) == get_irg_frame(get_irn_irg(irn))) {
+
+               return get_Sel_entity(irn);
+       }
+
+       return NULL;
+}
+
+static void lower_frame_sels_walker(ir_node *irn, void *data)
+{
+       const arch_register_class_t *cls;
+       be_abi_irg_t *env = data;
+       const arch_isa_t *isa = env->birg->main_env->arch_env->isa;
+       ir_graph *irg = get_irn_irg(irn);
+       ir_node *frame = get_irg_frame(irg);
+       ir_node *nw  = NULL;
+       opcode opc   = get_irn_opcode(irn);
+
+       if(opc == iro_Load) {
+               ir_node *bl  = get_nodes_block(irn);
+               ir_node *sel = get_Load_ptr(irn);
+               entity *ent  = get_sel_ent(sel);
+               cls = arch_isa_get_reg_class_for_mode(isa, get_Load_mode(irn));
+               if(ent != NULL)
+                       nw = be_new_FrameLoad(isa->sp->reg_class, cls, irg, bl, get_Load_mem(irn), frame, ent);
+       }
+
+       else if(opc == iro_Store) {
+               ir_node *bl  = get_nodes_block(irn);
+               ir_node *val = get_Store_value(irn);
+               ir_node *sel = get_Store_ptr(irn);
+               entity *ent  = get_sel_ent(sel);
+               cls = arch_isa_get_reg_class_for_mode(isa, get_irn_mode(val));
+               if(ent != NULL)
+                       nw = be_new_FrameStore(isa->sp->reg_class, cls, irg, bl, get_Store_mem(irn), frame, val, ent);
+       }
+
+       else {
+               entity *ent = get_sel_ent(irn);
+               if(ent != NULL) {
+                       ir_node *bl  = get_nodes_block(irn);
+                       nw = be_new_FrameAddr(isa->sp->reg_class, irg, bl, frame, ent);
+               }
+       }
+
+       if(nw != NULL)
+               exchange(irn, nw);
+}
+
 static INLINE int is_on_stack(be_abi_call_t *call, int pos)
 {
        be_abi_call_arg_t *arg = get_call_arg(call, 0, pos);
@@ -167,9 +297,15 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
        /* Let the isa fill out the abi description for that call node. */
        arch_isa_get_call_abi(isa, mt, call);
 
+       // assert(get_method_variadicity(mt) == variadicity_non_variadic);
+
        /* Insert code to put the stack arguments on the stack. */
-       for(i = get_irn_arity(irn); i >= 0; --i) {
-               if(is_on_stack(call, i)) {
+       /* TODO: Vargargs */
+       assert(get_Call_n_params(irn) == n_params);
+       for(i = 0; i < n_params; ++i) {
+               be_abi_call_arg_t *arg = get_call_arg(call, 0, i);
+               assert(arg);
+               if(!arg->in_reg) {
                        stack_size += get_type_size_bytes(get_method_param_type(mt, i));
                        obstack_int_grow(obst, i);
                        n_pos++;
@@ -178,7 +314,7 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
        pos = obstack_finish(obst);
 
        /* Collect all arguments which are passed in registers. */
-       for(i = 0, n = get_irn_arity(irn); i < n; ++i) {
+       for(i = 0, n = get_Call_n_params(irn); i < n; ++i) {
                be_abi_call_arg_t *arg = get_call_arg(call, 0, i);
                if(arg && arg->in_reg) {
                        obstack_int_grow(obst, i);
@@ -215,7 +351,7 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
                assert(mode_is_reference(mach_mode) && "machine mode must be pointer");
                for(i = 0; i < n_pos; ++i) {
                        int p            = pos[i];
-                       ir_node *param   = get_irn_n(irn, p);
+                       ir_node *param   = get_Call_param(irn, p);
                        ir_node *addr    = curr_sp;
                        ir_node *mem     = NULL;
                        type *param_type = get_method_param_type(mt, p);
@@ -273,8 +409,15 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
        }
 
        /* Collect caller save registers */
-       for(i = 0; env->birg->main_env->caller_save[i]; ++i)
-               pset_insert_ptr(caller_save, env->birg->main_env->caller_save[i]);
+       for(i = 0, n = arch_isa_get_n_reg_class(isa); i < n; ++i) {
+               int j;
+               const arch_register_class_t *cls = arch_isa_get_reg_class(isa, i);
+               for(j = 0; j < cls->n_regs; ++j) {
+                       const arch_register_t *reg = arch_register_for_index(cls, j);
+                       if(arch_register_type_is(reg, caller_save))
+                               pset_insert_ptr(caller_save, (void *) reg);
+               }
+       }
 
        /* search the greatest result proj number */
        foreach_out_edge(irn, edge) {
@@ -300,6 +443,15 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
        }
        curr_res_proj++;
 
+       /* make the back end call node and set its register requirements. */
+       for(i = 0; i < n_low_args; ++i)
+               obstack_ptr_grow(obst, get_Call_param(irn, low_args[i]));
+
+       in = obstack_finish(obst);
+       low_call = be_new_Call(irg, bl, curr_mem, curr_sp, get_Call_ptr(irn), curr_res_proj, n_low_args, in);
+       obstack_free(obst, in);
+       exchange(irn, low_call);
+
        /* Make additional projs for the caller save registers
           and the Keep node which keeps them alive. */
        if(pset_count(caller_save) > 0) {
@@ -307,7 +459,7 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
                ir_node **in;
 
                if(!res_proj)
-                       res_proj = new_r_Proj(irg, bl, irn, mode_T, pn_Call_T_result);
+                       res_proj = new_r_Proj(irg, bl, low_call, mode_T, pn_Call_T_result);
 
                for(reg = pset_first(caller_save); reg; reg = pset_next(caller_save))
                        obstack_ptr_grow(obst, new_r_Proj(irg, bl, res_proj, reg->reg_class->mode, curr_res_proj++));
@@ -323,7 +475,7 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
 
                /* Get the result ProjT */
                if(!res_proj)
-                       res_proj = new_r_Proj(irg, bl, irn, mode_T, pn_Call_T_result);
+                       res_proj = new_r_Proj(irg, bl, low_call, mode_T, pn_Call_T_result);
 
                /* Make a Proj for the stack pointer. */
                sp_proj     = new_r_Proj(irg, bl, res_proj, sp->reg_class->mode, curr_res_proj++);
@@ -331,15 +483,6 @@ static void adjust_call(be_abi_irg_t *env, ir_node *irn)
                pset_insert_ptr(env->stack_ops, last_inc_sp);
        }
 
-       /* at last make the backend call node and set its register requirements. */
-       for(i = 0; i < n_low_args; ++i)
-               obstack_ptr_grow(obst, get_irn_n(irn, low_args[i]));
-       in = obstack_finish(obst);
-       low_call = be_new_Call(irg, bl, curr_mem, curr_sp, get_Call_ptr(irn), curr_res_proj, n_low_args, in);
-       obstack_free(obst, in);
-
-       exchange(irn, low_call);
-
        be_abi_call_free(call);
        obstack_free(obst, pos);
        del_pset(results);
@@ -411,13 +554,15 @@ static ir_node *setup_frame(be_abi_irg_t *env)
                if(store_old_fp) {
                        ir_node *irn;
 
-                       irn   = new_r_Store(irg, bl, get_irg_initial_mem(irg), stack, frame);
-                       irn   = new_r_Proj(irg, bl, irn, mode_M, pn_Store_M);
-                       stack = be_new_IncSP(sp, irg, bl, stack, irn, get_mode_size_bytes(bp->reg_class->mode), be_stack_dir_along);
+                       irn               = new_r_Store(irg, bl, get_irg_initial_mem(irg), stack, frame);
+                       env->store_bp_mem = new_r_Proj(irg, bl, irn, mode_M, pn_Store_M);
+                       stack             = be_new_IncSP(sp, irg, bl, stack, env->store_bp_mem,
+                                                                                               get_mode_size_bytes(bp->reg_class->mode), be_stack_dir_along);
                }
 
                frame = be_new_Copy(bp->reg_class, irg, bl, stack);
 
+               be_node_set_flags(frame, -1, arch_irn_flags_dont_spill);
                if(env->dedicated_fp) {
                        be_set_constr_single_reg(frame, -1, bp);
                        be_node_set_flags(frame, -1, arch_irn_flags_ignore);
@@ -434,9 +579,92 @@ static ir_node *setup_frame(be_abi_irg_t *env)
        return frame;
 }
 
-static ir_node *clearup_frame(be_abi_irg_t *env, ir_node *stack, ir_node *frame)
+static void clearup_frame(be_abi_irg_t *env, ir_node *bl, struct obstack *obst)
+{
+       const arch_isa_t *isa = env->birg->main_env->arch_env->isa;
+       const arch_register_t *sp = isa->sp;
+       const arch_register_t *bp = isa->bp;
+       ir_graph *irg      = env->birg->irg;
+       ir_node *no_mem    = get_irg_no_mem(irg);
+       ir_node *frame     = get_irg_frame(irg);
+       ir_node *stack     = env->init_sp;
+       int store_old_fp   = 1;
+
+       pmap_entry *ent;
+
+
+       if(env->omit_fp) {
+               stack = be_new_IncSP(sp, irg, bl, stack, no_mem, BE_STACK_FRAME_SIZE, be_stack_dir_against);
+       }
+
+       else {
+               stack = be_new_Copy(sp->reg_class, irg, bl, frame);
+               be_set_constr_single_reg(stack, -1, sp);
+               be_node_set_flags(stack, -1, arch_irn_flags_ignore);
+
+               if(store_old_fp) {
+                       ir_mode *mode = sp->reg_class->mode;
+                       ir_node *irn;
+
+                       stack = be_new_IncSP(sp, irg, bl, stack, no_mem, get_mode_size_bytes(mode), be_stack_dir_against);
+                       irn   = new_r_Load(irg, bl, env->store_bp_mem, stack, mode);
+                       irn   = new_r_Proj(irg, bl, irn, mode, pn_Load_res);
+                       frame = be_new_Copy(bp->reg_class, irg, bl, irn);
+               }
+       }
+
+       pmap_foreach(env->regs, ent) {
+               const arch_register_t *reg = ent->key;
+               ir_node *irn               = ent->value;
+
+               if(reg == sp)
+                       irn = stack;
+               else if(reg == bp)
+                       irn = frame;
+
+               obstack_ptr_grow(obst, irn);
+       }
+}
+
+static ir_type *compute_arg_type(be_abi_irg_t *env, be_abi_call_t *call, ir_type *method_type)
 {
+       int inc  = env->birg->main_env->arch_env->isa->stack_dir * (env->left_to_right ? 1 : -1);
+       int n    = get_method_n_params(method_type);
+       int curr = inc > 0 ? 0 : n - 1;
+       int ofs  = 0;
+
+       char buf[128];
+       ir_type *res;
+       int i;
+
+       snprintf(buf, sizeof(buf), "%s_arg_type", get_entity_name(get_irg_entity(env->birg->irg)));
+       res = new_type_class(new_id_from_str(buf));
+
+       for(i = 0; i < n; ++i, curr += inc) {
+               type *param_type       = get_method_param_type(method_type, curr);
+               be_abi_call_arg_t *arg = get_call_arg(call, 0, curr);
 
+               if(!arg->in_reg) {
+                       snprintf(buf, sizeof(buf), "param_%d", i);
+                       arg->stack_ent = new_entity(res, new_id_from_str(buf), param_type);
+                       add_class_member(res, arg->stack_ent);
+                       set_entity_offset_bytes(arg->stack_ent, ofs);
+                       ofs += get_type_size_bytes(param_type);
+               }
+       }
+
+       set_type_size_bytes(res, ofs);
+       return res;
+}
+
+static type *get_bp_type(const arch_register_t *bp)
+{
+       static type *bp_type = NULL;
+       if(!bp_type) {
+               bp_type = new_type_primitive(new_id_from_str("bp_type"), bp->reg_class->mode);
+               set_type_size_bytes(bp_type, get_mode_size_bytes(bp->reg_class->mode));
+       }
+       return bp_type;
 }
 
 /**
@@ -455,7 +683,6 @@ static void modify_irg(be_abi_irg_t *env)
        ir_node *no_mem           = get_irg_no_mem(irg);
        type *method_type         = get_entity_type(get_irg_entity(irg));
        int n_params              = get_method_n_params(method_type);
-
        int max_arg               = 0;
        int reg_params_nr         = 0;
        int arg_offset            = 0;
@@ -466,13 +693,18 @@ static void modify_irg(be_abi_irg_t *env)
        ir_node *reg_params, *reg_params_bl;
        ir_node **args, **args_repl;
        const ir_edge_t *edge;
+       ir_type *arg_type;
 
        pmap_entry *ent;
 
-       env->regs = pmap_create();
-
        DBG((dbg, LEVEL_1, "introducing abi on %+F\n", irg));
 
+       /* Convert the Sel nodes in the irg to frame load/store/addr nodes. */
+       irg_walk_graph(irg, lower_frame_sels_walker, NULL, env);
+
+       env->frame = obstack_alloc(&env->obst, sizeof(env->frame[0]));
+       env->regs  = pmap_create();
+
        /* Find the maximum proj number of the argument tuple proj */
        foreach_out_edge(arg_tuple, edge)  {
                ir_node *irn = get_edge_src_irn(edge);
@@ -496,6 +728,9 @@ static void modify_irg(be_abi_irg_t *env)
        /* Get the ABI constraints from the ISA */
        arch_isa_get_call_abi(isa, method_type, call);
 
+       arg_type     = compute_arg_type(env, call, method_type);
+       stack_frame_init(env->frame, arg_type, call->between_type, get_irg_frame_type(irg), isa->stack_dir);
+
        /* Count the register params and add them to the number of Projs for the RegParams node */
        for(i = 0; i < n_params; ++i) {
                be_abi_call_arg_t *arg = get_call_arg(call, 0, i);
@@ -547,95 +782,40 @@ static void modify_irg(be_abi_irg_t *env)
        /* Insert the code to set up the stack frame */
        frame_pointer = setup_frame(env);
 
-#if 0
-       proj_sp = pmap_get(regs, (void *) sp);
-       proj_bp = pmap_get(regs, (void *) bp);
-       assert(proj_sp != NULL && "There must be a Proj for the stack pointer");
-       assert(proj_sp != NULL && "There must be a Proj for the base pointer");
-
-       /* Set the Proj for the stack pointer to ignore. */
-       be_node_set_flags(reg_params, -(get_Proj_proj(proj_sp) + 1), arch_irn_flags_ignore);
-
-       /*
-        * If a frame pointer is needed and the frame pointer is in a dedicated register,
-        * also exclude that from register allocation by setting the corresponding
-        * Proj to ignore.
-        */
-       if(!env->omit_fp && env->dedicated_fp)
-               be_node_set_flags(reg_params, -(get_Proj_proj(proj_bp) + 1), arch_irn_flags_ignore);
-
-
-       if(env->omit_fp) {
-               /* This is the stack pointer add/sub which allocates the frame. remind it for later fix up. */
-               env->init_sp  = be_new_IncSP(sp, irg, reg_params_bl, proj_sp, no_mem, 0, be_stack_dir_along);
-               frame_pointer = env->init_sp;
-       }
-
-       else {
-               env->init_sp  = proj_sp;
-               frame_pointer = be_new_Copy(sp->reg_class, irg, reg_params_bl, proj_sp);
-       }
-
-       /* Set the new frame pointer. */
-       exchange(get_irg_frame(irg), frame_pointer);
-       set_irg_frame(irg, frame_pointer);
-#endif
-
-       /* compute the start offset for the stack parameters. */
-       {
-               int arg_offset = 0;
-               int arg_size   = 0;
-               int inc_dir    = isa->stack_dir * (env->left_to_right ? 1 : -1);
-
-               for(i = 0; i < n_params; ++i) {
-                       be_abi_call_arg_t *arg = get_call_arg(call, 0, i);
-                       if(!arg->in_reg)
-                               arg_size += get_type_size_bytes(get_method_param_type(method_type, i));
-               }
-
-               arg_offset = -isa->stack_dir * call->arg_gap + env->left_to_right * arg_size;
-
-               /* Now, introduce stack param nodes for all parameters passed on the stack */
-               for(i = 0; i < max_arg; ++i) {
-                       ir_node *arg_proj = args[i];
-                       if(arg_proj != NULL) {
-                               be_abi_call_arg_t *arg;
-                               ir_type *param_type;
-                               int nr = get_Proj_proj(arg_proj);
+       /* Now, introduce stack param nodes for all parameters passed on the stack */
+       for(i = 0; i < max_arg; ++i) {
+               ir_node *arg_proj = args[i];
+               if(arg_proj != NULL) {
+                       be_abi_call_arg_t *arg;
+                       ir_type *param_type;
+                       int nr = get_Proj_proj(arg_proj);
+
+                       nr         = MIN(nr, n_params);
+                       arg        = get_call_arg(call, 0, nr);
+                       param_type = get_method_param_type(method_type, nr);
+
+                       if(arg->in_reg) {
+                               args_repl[i] = new_r_Proj(irg, reg_params_bl, reg_params, get_irn_mode(arg_proj), reg_params_nr);
+                               be_set_constr_single_reg(reg_params, -(reg_params_nr + 1), arg->reg);
+                               reg_params_nr++;
+                       }
 
-                               nr         = MIN(nr, n_params);
-                               arg        = get_call_arg(call, 0, nr);
-                               param_type = get_method_param_type(method_type, nr);
+                       /* when the (stack) parameter is primitive, we insert a StackParam
+                       node representing the load of that parameter */
+                       else {
 
-                               if(arg->in_reg) {
-                                       args_repl[i] = new_r_Proj(irg, reg_params_bl, reg_params, get_irn_mode(arg_proj), reg_params_nr);
-                                       be_set_constr_single_reg(reg_params, -(reg_params_nr + 1), arg->reg);
-                                       reg_params_nr++;
+                               /* For atomic parameters which are actually used, we create a StackParam node. */
+                               if(is_atomic_type(param_type) && get_irn_n_edges(args[i]) > 0) {
+                                       ir_mode *mode                    = get_type_mode(param_type);
+                                       const arch_register_class_t *cls = arch_isa_get_reg_class_for_mode(isa, mode);
+                                       args_repl[i] = be_new_StackParam(cls, irg, reg_params_bl, mode, frame_pointer, arg->stack_ent);
                                }
 
-                               /* when the (stack) parameter is primitive, we insert a StackParam
-                               node representing the load of that parameter */
+                               /* The stack parameter is not primitive (it is a struct or array),
+                               we thus will create a node representing the parameter's address
+                               on the stack. */
                                else {
-                                       int size = get_type_size_bytes(param_type) * isa->stack_dir;
-
-                                       if(inc_dir < 0)
-                                               arg_offset -= size;
-
-                                       if(is_atomic_type(param_type)) {
-                                               ir_mode *mode                    = get_type_mode(param_type);
-                                               const arch_register_class_t *cls = arch_isa_get_reg_class_for_mode(isa, mode);
-                                               args_repl[i] = be_new_StackParam(cls, irg, reg_params_bl, mode, frame_pointer, arg_offset);
-                                       }
-
-                                       /* The stack parameter is not primitive (it is a struct or array),
-                                       we thus will create a node representing the parameter's address
-                                       on the stack. */
-                                       else {
-                                               assert(0 && "struct parameters are not supported");
-                                       }
-
-                                       if(inc_dir > 0)
-                                               arg_offset += size;
+                                       args_repl[i] = be_new_FrameAddr(sp->reg_class, irg, reg_params_bl, frame_pointer, arg->stack_ent);
                                }
                        }
                }
@@ -654,37 +834,40 @@ static void modify_irg(be_abi_irg_t *env)
                ir_node *irn = get_irn_n(end, i);
 
                if(get_irn_opcode(irn) == iro_Return) {
-                       ir_node *bl = get_nodes_block(irn);
+                       ir_node *bl   = get_nodes_block(irn);
+                       int n_res     = get_Return_n_ress(irn);
+                       pmap *reg_map = pmap_create_ex(n_res);
                        ir_node *ret;
                        int i, n;
                        ir_node **in;
 
                        /* collect all arguments of the return */
-                       for(i = 0, n = get_irn_arity(irn); i < n; ++i)
-                               obstack_ptr_grow(&env->obst, get_irn_n(irn, i));
+                       for(i = 0; i < n_res; ++i) {
+                               ir_node *res           = get_Return_res(irn, i);
+                               be_abi_call_arg_t *arg = get_call_arg(call, 1, i);
 
-                       /* Add the Proj nodes representing the caller save registers. */
-                       for(ent = pmap_first(env->regs); ent; ent = pmap_next(env->regs), ++n) {
-                               const arch_register_t *reg = ent->key;
-                               ir_node *irn               = ent->value;
-
-                               /*
-                                * If the register is the stack pointer,
-                                * add the fix up code. Either add the size of the stack
-                                * frame if we omitted the frame pointer or move the
-                                * frame pointer back to the stack register.
-                                */
-                               if(reg == sp) {
-                                       irn = be_new_IncSP(sp, irg, bl, frame_pointer, no_mem, env->omit_fp ? BE_STACK_FRAME_SIZE : 0, be_stack_dir_against);
-                               }
-                               obstack_ptr_grow(&env->obst, irn);
+                               assert(arg->in_reg && "return value must be passed in register");
+                               pmap_insert(reg_map, res, (void *) arg->reg);
+                               obstack_ptr_grow(&env->obst, res);
                        }
 
+                       /* generate the clean up code and add additional parameters to the return. */
+                       clearup_frame(env, bl, &env->obst);
+
                        /* The in array for the new back end return is now ready. */
+                       n   = obstack_object_size(&env->obst) / sizeof(in[0]);
                        in  = obstack_finish(&env->obst);
                        ret = be_new_Return(irg, bl, n, in);
-                       edges_reroute(irn, ret, irg);
+
+                       /* Set the constraints for some arguments of the return. */
+                       for(i = 0; i < n; i++) {
+                               const arch_register_t *reg = pmap_get(reg_map, in[i]);
+                               if(reg != NULL)
+                                       be_set_constr_single_reg(ret, i, reg);
+                       }
+                       exchange(irn, ret);
                        obstack_free(&env->obst, in);
+                       pmap_destroy(reg_map);
                }
        }
 
@@ -713,6 +896,7 @@ be_abi_irg_t *be_abi_introduce(be_irg_t *birg)
        env->omit_fp       = (env->call->flags & BE_ABI_TRY_OMIT_FRAME_POINTER) != 0;
        env->dedicated_fp  = (env->call->flags & BE_ABI_FRAME_POINTER_DEDICATED) != 0;
        env->left_to_right = (env->call->flags & BE_ABI_LEFT_TO_RIGHT) != 0;
+       env->save_old_fp   = (env->call->flags & BE_ABI_SAVE_OLD_FRAME_POINTER) != 0;
        env->birg          = birg;
        env->stack_ops     = pset_new_ptr(32);
        env->dbg           = firm_dbg_register("firm.be.abi");
@@ -789,8 +973,9 @@ static int process_stack_bias(be_abi_irg_t *env, ir_node *bl, int bias)
                        bias += dir * ofs;
                }
 
-               else
+               else {
                        arch_set_stack_bias(aenv, irn, bias);
+               }
        }
 
        return bias;
@@ -822,7 +1007,7 @@ void be_abi_free(be_abi_irg_t *env)
        free(env);
 }
 
-ir_node *be_abi_get_callee_save_node(be_abi_irg_t *abi, const arch_register_t *reg)
+ir_node *be_abi_get_callee_save_irn(be_abi_irg_t *abi, const arch_register_t *reg)
 {
        assert(arch_register_type_is(reg, callee_save));
        assert(pmap_contains(abi->regs, (void *) reg));