X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Flower%2Flower_hl.c;h=d6edda50b89964f6b995ad18f5d3310581e62a37;hb=ef63002fcb03a29f1b4e041c067d0fa8546bed96;hp=f30e76dbe02cab126a87ee0a18d7e003391ee891;hpb=300c3b362f0625521b30e6dc378139f129d9dc9f;p=libfirm

diff --git a/ir/lower/lower_hl.c b/ir/lower/lower_hl.c
index f30e76dbe..d6edda50b 100644
--- a/ir/lower/lower_hl.c
+++ b/ir/lower/lower_hl.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 1995-2007 University of Karlsruhe.  All right reserved.
+ * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
  *
  * This file is part of libFirm.
  *
@@ -23,9 +23,7 @@
  * @author  Boris Boesler, Goetz Lindenmaier, Michael Beck
  * @version $Id$
  */
-#ifdef HAVE_CONFIG_H
-# include "config.h"
-#endif
+#include "config.h"
 
 #include "lowering.h"
 #include "irmode_t.h"
@@ -37,11 +35,14 @@
 #include "irhooks.h"
 #include "irgmod.h"
 #include "irgwalk.h"
+#include "irtools.h"
+#include "irpass_t.h"
 
 /**
  * Lower a Sel node. Do not touch Sels accessing entities on the frame type.
  */
-static void lower_sel(ir_node *sel) {
+static void lower_sel(ir_node *sel)
+{
 	ir_graph *irg = current_ir_graph;
 	ir_entity   *ent;
 	ir_node  *newn, *cnst, *index, *ptr, *bl;
@@ -52,21 +53,21 @@ static void lower_sel(ir_node *sel) {
 
 	assert(is_Sel(sel));
 
+	/* Do not lower frame type/global offset table access: must be lowered by the backend. */
+	ptr = get_Sel_ptr(sel);
+	if (ptr == get_irg_frame(current_ir_graph))
+		return;
+
 	ent   = get_Sel_entity(sel);
 	owner = get_entity_owner(ent);
 
-	/* Do not lower frame type access: must be lowered by the backend. */
-	if (is_frame_type(owner))
-		return;
-
 	/*
-	 * Cannot handle value param entities here.
+	 * Cannot handle value param entities or frame type entities here.
 	 * Must be lowered by the backend.
 	 */
-	if (is_value_param_type(owner))
+	if (is_value_param_type(owner) || is_frame_type(owner))
 		return;
 
-	ptr  = get_Sel_ptr(sel);
 	dbg  = get_irn_dbg_info(sel);
 	mode = get_irn_mode(sel);
 
@@ -79,8 +80,8 @@ static void lower_sel(ir_node *sel) {
 		sym.entity_p = ent;
 		bl = get_nodes_block(sel);
 
-		cnst = new_rd_SymConst(dbg, irg, bl, sym, symconst_addr_ent);
-		newn = new_rd_Add(dbg, irg, bl, ptr, cnst, mode);
+		cnst = new_rd_SymConst(dbg, irg, mode, sym, symconst_addr_ent);
+		newn = new_rd_Add(dbg, bl, ptr, cnst, mode);
 	} else {
 		/* not TLS */
 
@@ -97,15 +98,15 @@ static void lower_sel(ir_node *sel) {
 				basemode = mode_P_data;
 
 			assert(basemode && "no mode for lowering Sel");
-			assert((get_mode_size_bytes(basemode) != -1) && "can not deal with unorthodox modes");
+			assert((get_mode_size_bits(basemode) % 8 == 0) && "can not deal with unorthodox modes");
 			index = get_Sel_index(sel, 0);
 
 			if (is_Array_type(owner)) {
-				ir_node *last_size;
 				ir_type *arr_ty = owner;
-				int dims = get_array_n_dimensions(arr_ty);
-				int *map = alloca(sizeof(int) * dims);
-				int i;
+				int      dims   = get_array_n_dimensions(arr_ty);
+				int     *map    = ALLOCAN(int, dims);
+				ir_node *last_size;
+				int      i;
 
 				assert(dims == get_Sel_n_indexs(sel)
 					&& "array dimension must match number of indices of Sel node");
@@ -121,7 +122,7 @@ static void lower_sel(ir_node *sel) {
 
 				/* Size of the array element */
 				tv = new_tarval_from_long(get_type_size_bytes(basetyp), mode_Int);
-				last_size = new_rd_Const(dbg, irg, get_irg_start_block(irg), mode_Int, tv);
+				last_size = new_rd_Const(dbg, irg, tv);
 
 				/*
 				 * We compute the offset part of dimension d_i recursively
@@ -142,13 +143,13 @@ static void lower_sel(ir_node *sel) {
 					ub = get_array_upper_bound(arr_ty, dim);
 
 					assert(irg == current_ir_graph);
-					if (get_irn_op(lb) != op_Unknown)
-						lb = new_rd_Conv(dbg, irg, bl, copy_const_value(get_irn_dbg_info(sel), lb), mode_Int);
+					if (! is_Unknown(lb))
+						lb = new_rd_Conv(dbg, bl, copy_const_value(get_irn_dbg_info(sel), lb), mode_Int);
 					else
 						lb = NULL;
 
-					if (get_irn_op(ub) != op_Unknown)
-						ub = new_rd_Conv(dbg, irg, bl, copy_const_value(get_irn_dbg_info(sel), ub), mode_Int);
+					if (! is_Unknown(ub))
+						ub = new_rd_Conv(dbg, bl, copy_const_value(get_irn_dbg_info(sel), ub), mode_Int);
 					else
 						ub = NULL;
 
@@ -157,73 +158,79 @@ static void lower_sel(ir_node *sel) {
 					 * bounds have to be set in the non-last dimension.
 					 */
 					if (i > 0) {
-						assert(lb && "lower bound has to be set in multi-dim array");
-						assert(lb && "upper bound has to be set in multi-dim array");
+						assert(lb != NULL && "lower bound has to be set in multi-dim array");
+						assert(ub != NULL && "upper bound has to be set in multi-dim array");
 
 						/* Elements in one Dimension */
-						elms = new_rd_Sub(dbg, irg, bl, ub, lb, mode_Int);
+						elms = new_rd_Sub(dbg, bl, ub, lb, mode_Int);
 					}
 
-					ind = new_rd_Conv(dbg, irg, bl, get_Sel_index(sel, dim), mode_Int);
+					ind = new_rd_Conv(dbg, bl, get_Sel_index(sel, dim), mode_Int);
 
 					/*
 					 * Normalize index, id lower bound is set, also assume
 					 * lower bound == 0
 					 */
-					if (lb)
-						ind = new_rd_Sub(dbg, irg, bl, ind, lb, mode_Int);
+					if (lb != NULL)
+						ind = new_rd_Sub(dbg, bl, ind, lb, mode_Int);
 
-					n = new_rd_Mul(dbg, irg, bl, ind, last_size, mode_Int);
+					n = new_rd_Mul(dbg, bl, ind, last_size, mode_Int);
 
 					/*
 					 * see comment above.
 					 */
 					if (i > 0)
-						last_size = new_rd_Mul(dbg, irg, bl, last_size, elms, mode_Int);
+						last_size = new_rd_Mul(dbg, bl, last_size, elms, mode_Int);
 
-					newn = new_rd_Add(dbg, irg, bl, newn, n, mode);
+					newn = new_rd_Add(dbg, bl, newn, n, mode);
 				}
 			} else {
 				/* no array type */
 				ir_mode *idx_mode = get_irn_mode(index);
 				tarval *tv = new_tarval_from_long(get_mode_size_bytes(basemode), idx_mode);
 
-				newn = new_rd_Add(dbg, irg, bl, get_Sel_ptr(sel),
-					new_rd_Mul(dbg, irg, bl, index,
-					new_r_Const(irg, get_irg_start_block(irg), idx_mode, tv),
+				newn = new_rd_Add(dbg, bl, get_Sel_ptr(sel),
+					new_rd_Mul(dbg, bl, index,
+					new_r_Const(irg, tv),
 					idx_mode),
 					mode);
 			}
 		} else if (is_Method_type(get_entity_type(ent)) &&
-	               is_Class_type(owner) &&
-	               (owner != get_glob_type()) &&
-	               (!is_frame_type(owner)))  {
+		           is_Class_type(owner) &&
+		           (owner != get_glob_type()) &&
+		           (!is_frame_type(owner)))  {
 			ir_node *add;
 			ir_mode *ent_mode = get_type_mode(get_entity_type(ent));
 
 			/* We need an additional load when accessing methods from a dispatch table. */
 			tv   = new_tarval_from_long(get_entity_offset(ent), mode_Int);
-			cnst = new_rd_Const(dbg, irg, get_irg_start_block(irg), mode_Int, tv);
-			add  = new_rd_Add(dbg, irg, bl, get_Sel_ptr(sel), cnst, mode);
+			cnst = new_rd_Const(dbg, irg, tv);
+			add  = new_rd_Add(dbg, bl, get_Sel_ptr(sel), cnst, mode);
 #ifdef DO_CACHEOPT  /* cacheopt version */
-			newn = new_rd_Load(dbg, irg, bl, get_Sel_mem(sel), sel, ent_mode);
+			newn = new_rd_Load(dbg, bl, get_Sel_mem(sel), sel, ent_mode, 0);
 			cacheopt_map_addrs_register_node(newn);
 			set_Load_ptr(newn, add);
 #else /* normal code */
-			newn = new_rd_Load(dbg, irg, bl, get_Sel_mem(sel), add, ent_mode);
+			newn = new_rd_Load(dbg, bl, get_Sel_mem(sel), add, ent_mode, 0);
 #endif
-			newn = new_r_Proj(irg, bl, newn, ent_mode, pn_Load_res);
+			newn = new_r_Proj(bl, newn, ent_mode, pn_Load_res);
+
+		} else if (get_entity_owner(ent) != get_glob_type()) {
+			int offset;
 
-		} else if (get_entity_owner(ent) != get_glob_type())  {
 			/* replace Sel by add(obj, const(ent.offset)) */
-			assert(!(get_entity_allocation(ent) == allocation_static &&
-				(get_entity_n_overwrites(ent) == 0 && get_entity_n_overwrittenby(ent) == 0)));
-			tv = new_tarval_from_long(get_entity_offset(ent), mode_Int);
-			cnst = new_r_Const(irg, get_irg_start_block(irg), mode_Int, tv);
-			newn = new_rd_Add(dbg, irg, bl, get_Sel_ptr(sel), cnst, mode);
+			newn   = get_Sel_ptr(sel);
+			offset = get_entity_offset(ent);
+			if (offset != 0) {
+				ir_mode *mode_UInt = get_reference_mode_unsigned_eq(mode);
+
+				tv = new_tarval_from_long(offset, mode_UInt);
+				cnst = new_r_Const(irg, tv);
+				newn = new_rd_Add(dbg, bl, newn, cnst, mode);
+			}
 		} else {
 			/* global_type */
-			newn = new_rd_SymConst_addr_ent(NULL, current_ir_graph, ent, firm_unknown_type);
+			newn = new_rd_SymConst_addr_ent(NULL, irg, mode, ent, firm_unknown_type);
 		}
 	}
 	/* run the hooks */
@@ -235,7 +242,8 @@ static void lower_sel(ir_node *sel) {
 /**
  * Lower a all possible SymConst nodes.
  */
-static void lower_symconst(ir_node *symc) {
+static void lower_symconst(ir_node *symc)
+{
 	ir_node       *newn;
 	ir_type       *tp;
 	ir_entity     *ent;
@@ -252,10 +260,7 @@ static void lower_symconst(ir_node *symc) {
 		tp   = get_SymConst_type(symc);
 		assert(get_type_state(tp) == layout_fixed);
 		mode = get_irn_mode(symc);
-		tv   = new_tarval_from_long(get_type_size_bytes(tp), mode);
-		newn = new_r_Const(current_ir_graph,
-		                   get_irg_start_block(current_ir_graph),
-		                   get_irn_mode(symc), tv);
+		newn = new_Const_long(mode, get_type_size_bytes(tp));
 		assert(newn);
 		/* run the hooks */
 		hook_lower(symc);
@@ -266,18 +271,12 @@ static void lower_symconst(ir_node *symc) {
 		tp   = get_SymConst_type(symc);
 		assert(get_type_state(tp) == layout_fixed);
 		mode = get_irn_mode(symc);
-		tv   = new_tarval_from_long(get_type_alignment_bytes(tp), mode);
-		newn = new_r_Const(current_ir_graph,
-		                   get_irg_start_block(current_ir_graph),
-		                   mode, tv);
+		newn = new_Const_long(mode, get_type_alignment_bytes(tp));
 		assert(newn);
 		/* run the hooks */
 		hook_lower(symc);
 		exchange(symc, newn);
 		break;
-	case symconst_addr_name:
-		/* do not rewrite - pass info to back end */
-		break;
 	case symconst_addr_ent:
 		/* leave */
 		break;
@@ -286,10 +285,7 @@ static void lower_symconst(ir_node *symc) {
 		ent  = get_SymConst_entity(symc);
 		assert(get_type_state(get_entity_type(ent)) == layout_fixed);
 		mode = get_irn_mode(symc);
-		tv   = new_tarval_from_long(get_entity_offset(ent), mode);
-		newn = new_r_Const(current_ir_graph,
-		                   get_irg_start_block(current_ir_graph),
-		                   mode, tv);
+		newn = new_Const_long(mode, get_entity_offset(ent));
 		assert(newn);
 		/* run the hooks */
 		hook_lower(symc);
@@ -300,17 +296,12 @@ static void lower_symconst(ir_node *symc) {
 		ec   = get_SymConst_enum(symc);
 		assert(get_type_state(get_enumeration_owner(ec)) == layout_fixed);
 		tv   = get_enumeration_value(ec);
-		newn = new_r_Const(current_ir_graph,
-				  get_irg_start_block(current_ir_graph),
-				  get_irn_mode(symc), tv);
+		newn = new_Const(tv);
 		assert(newn);
 		/* run the hooks */
 		hook_lower(symc);
 		exchange(symc, newn);
 		break;
-	case symconst_label:
-		/* leave */
-		break;
 
 	default:
 		assert(!"unknown SymConst kind");
@@ -323,7 +314,8 @@ static void lower_symconst(ir_node *symc) {
  *
  * @param size  the size on bits
  */
-static int is_integral_size(int size) {
+static int is_integral_size(int size)
+{
 	/* must be a 2^n */
 	if (size & (size-1))
 		return 0;
@@ -337,7 +329,8 @@ static int is_integral_size(int size) {
  * @param proj  the Proj(result) node
  * @param load  the Load node
  */
-static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
+static void lower_bitfields_loads(ir_node *proj, ir_node *load)
+{
 	ir_node *sel = get_Load_ptr(load);
 	ir_node *block, *n_proj, *res, *ptr;
 	ir_entity *ent;
@@ -346,12 +339,16 @@ static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
 	int offset, bit_offset, bits, bf_bits, old_cse;
 	dbg_info *db;
 
-	if (get_irn_op(sel) != op_Sel)
+	if (!is_Sel(sel))
 		return;
 
 	ent     = get_Sel_entity(sel);
 	bf_type = get_entity_type(ent);
 
+	/* must be a bitfield type */
+	if (!is_Primitive_type(bf_type) || get_primitive_base_type(bf_type) == NULL)
+		return;
+
 	/* We have a bitfield access, if either a bit offset is given, or
 	   the size is not integral. */
 	bf_mode = get_type_mode(bf_type);
@@ -368,7 +365,6 @@ static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
 
 	bits   = get_mode_size_bits(mode);
 	offset = get_entity_offset(ent);
-	bit_offset += 8 * offset;
 
 	/*
 	 * ok, here we are: now convert the Proj_mode_bf(Load) into And(Shr(Proj_mode(Load)) for unsigned
@@ -378,6 +374,7 @@ static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
 	/* abandon bitfield sel */
 	ptr = get_Sel_ptr(sel);
 	db  = get_irn_dbg_info(sel);
+	ptr = new_rd_Add(db, block, ptr, new_Const_long(mode_Is, offset), get_irn_mode(ptr));
 
 	set_Load_ptr(load, ptr);
 	set_Load_mode(load, mode);
@@ -386,7 +383,7 @@ static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
 	/* create new proj, switch off CSE or we may get the old one back */
 	old_cse = get_opt_cse();
 	set_opt_cse(0);
-	res = n_proj = new_r_Proj(current_ir_graph, block, load, mode, pn_Load_res);
+	res = n_proj = new_r_Proj(block, load, mode, pn_Load_res);
 	set_opt_cse(old_cse);
 
 	if (mode_is_signed(mode)) { /* signed */
@@ -394,24 +391,20 @@ static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
 		int shift_count_down  = bits - bf_bits;
 
 		if (shift_count_up) {
-			res = new_r_Shl(current_ir_graph, block, res,
-				new_r_Const(current_ir_graph, block, mode_Iu, new_tarval_from_long(shift_count_up, mode_Iu)), mode);
+			res = new_r_Shl(block, res,	new_Const_long(mode_Iu, shift_count_up), mode);
 		}
 		if (shift_count_down) {
-			res = new_r_Shrs(current_ir_graph, block, res,
-				new_r_Const(current_ir_graph, block, mode_Iu, new_tarval_from_long(shift_count_down, mode_Iu)), mode);
+			res = new_r_Shrs(block, res, new_Const_long(mode_Iu, shift_count_down), mode);
 		}
 	} else { /* unsigned */
 		int shift_count_down  = bit_offset;
 		unsigned mask = ((unsigned)-1) >> (bits - bf_bits);
 
 		if (shift_count_down) {
-			res = new_r_Shr(current_ir_graph, block, res,
-				new_r_Const(current_ir_graph, block, mode_Iu, new_tarval_from_long(shift_count_down, mode_Iu)), mode);
+			res = new_r_Shr(block, res,	new_Const_long(mode_Iu, shift_count_down), mode);
 		}
 		if (bits != bf_bits) {
-			res = new_r_And(current_ir_graph, block, res,
-				new_r_Const(current_ir_graph, block, mode, new_tarval_from_long(mask, mode)), mode);
+			res = new_r_And(block, res, new_Const_long(mode, mask), mode);
 		}
 	}
 
@@ -423,7 +416,8 @@ static void lower_bitfields_loads(ir_node *proj, ir_node *load) {
  *
  * @todo: It adds a load which may produce an exception!
  */
-static void lower_bitfields_stores(ir_node *store) {
+static void lower_bitfields_stores(ir_node *store)
+{
 	ir_node   *sel = get_Store_ptr(store);
 	ir_node   *ptr, *value;
 	ir_entity *ent;
@@ -435,12 +429,16 @@ static void lower_bitfields_stores(ir_node *store) {
 	dbg_info *db;
 
 	/* check bitfield access */
-	if (get_irn_op(sel) != op_Sel)
+	if (!is_Sel(sel))
 		return;
 
 	ent     = get_Sel_entity(sel);
 	bf_type = get_entity_type(ent);
 
+	/* must be a bitfield type */
+	if (!is_Primitive_type(bf_type) || get_primitive_base_type(bf_type) == NULL)
+		return;
+
 	/* We have a bitfield access, if either a bit offset is given, or
 	   the size is not integral. */
 	bf_mode = get_type_mode(bf_type);
@@ -462,7 +460,6 @@ static void lower_bitfields_stores(ir_node *store) {
 	 */
 	mem        = get_Store_mem(store);
 	offset     = get_entity_offset(ent);
-	bit_offset += 8 * offset;
 
 	bits_mask = get_mode_size_bits(mode) - bf_bits;
 	mask = ((unsigned)-1) >> bits_mask;
@@ -472,25 +469,23 @@ static void lower_bitfields_stores(ir_node *store) {
 	/* abandon bitfield sel */
 	ptr = get_Sel_ptr(sel);
 	db  = get_irn_dbg_info(sel);
+	ptr = new_rd_Add(db, block, ptr, new_Const_long(mode_Is, offset), get_irn_mode(ptr));
 
 	if (neg_mask) {
 		/* there are some bits, normal case */
-		irn  = new_r_Load(current_ir_graph, block, mem, ptr, mode);
-		mem  = new_r_Proj(current_ir_graph, block, irn, mode_M, pn_Load_M);
-		irn  = new_r_Proj(current_ir_graph, block, irn, mode, pn_Load_res);
+		irn  = new_r_Load( block, mem, ptr, mode, 0);
+		mem  = new_r_Proj( block, irn, mode_M, pn_Load_M);
+		irn  = new_r_Proj( block, irn, mode, pn_Load_res);
 
-		irn = new_r_And(current_ir_graph, block, irn,
-			new_r_Const(current_ir_graph, block, mode, new_tarval_from_long(neg_mask, mode)), mode);
+		irn = new_r_And(block, irn, new_Const_long(mode, neg_mask), mode);
 
 		if (bit_offset > 0) {
-			value = new_r_Shl(current_ir_graph, block, value,
-				new_r_Const(current_ir_graph, block, mode_Iu, new_tarval_from_long(bit_offset, mode_Iu)), mode);
+			value = new_r_Shl(block, value, new_Const_long(mode_Iu, bit_offset), mode);
 		}
 
-		value = new_r_And(current_ir_graph, block, value,
-			new_r_Const(current_ir_graph, block, mode, new_tarval_from_long(mask, mode)), mode);
+		value = new_r_And(block, value, new_Const_long(mode, mask), mode);
 
-		value = new_r_Or(current_ir_graph, block, value, irn, mode);
+		value = new_r_Or(block, value, irn, mode);
 	}
 
 	set_Store_mem(store, mem);
@@ -498,10 +493,29 @@ static void lower_bitfields_stores(ir_node *store) {
 	set_Store_ptr(store, ptr);
 }  /* lower_bitfields_stores */
 
+/**
+ * Lowers unaligned Loads.
+ */
+static void lower_unaligned_Load(ir_node *load)
+{
+  (void) load;
+	/* NYI */
+}
+
+/**
+ * Lowers unaligned Stores
+ */
+static void lower_unaligned_Store(ir_node *store)
+{
+	(void) store;
+	/* NYI */
+}
+
 /**
  * lowers IR-nodes, called from walker
  */
-static void lower_irnode(ir_node *irn, void *env) {
+static void lower_irnode(ir_node *irn, void *env)
+{
 	(void) env;
 	switch (get_irn_opcode(irn)) {
 	case iro_Sel:
@@ -510,24 +524,35 @@ static void lower_irnode(ir_node *irn, void *env) {
 	case iro_SymConst:
 		lower_symconst(irn);
 		break;
+	case iro_Load:
+		if (env != NULL && get_Load_align(irn) == align_non_aligned)
+			lower_unaligned_Load(irn);
+		break;
+	case iro_Store:
+		if (env != NULL && get_Store_align(irn) == align_non_aligned)
+			lower_unaligned_Store(irn);
+		break;
+	case iro_Cast:
+		exchange(irn, get_Cast_op(irn));
+		break;
 	default:
 		break;
 	}
-}  /* lower_irnode */
+}
 
 /**
  * Walker: lowers IR-nodes for bitfield access
  */
-static void lower_bf_access(ir_node *irn, void *env) {
+static void lower_bf_access(ir_node *irn, void *env)
+{
 	(void) env;
 	switch (get_irn_opcode(irn)) {
 	case iro_Proj:
 	{
 		long proj     = get_Proj_proj(irn);
 		ir_node *pred = get_Proj_pred(irn);
-		ir_op *op     = get_irn_op(pred);
 
-		if ((proj == pn_Load_res) && (op == op_Load))
+		if (proj == pn_Load_res && is_Load(pred))
 			lower_bitfields_loads(irn, pred);
 		break;
 	}
@@ -538,26 +563,78 @@ static void lower_bf_access(ir_node *irn, void *env) {
 	default:
 		break;
 	}
-}  /* lower_bf_access */
+}
+
+/*
+ * Replaces SymConsts by a real constant if possible.
+ * Replace Sel nodes by address computation.  Also resolves array access.
+ * Handle Bitfields by added And/Or calculations.
+ */
+void lower_highlevel_graph(ir_graph *irg, int lower_bitfields)
+{
+	if (lower_bitfields) {
+		/* First step: lower bitfield access: must be run as long as Sels still
+		 * exists. */
+		irg_walk_graph(irg, NULL, lower_bf_access, NULL);
+	}
+
+	/* Finally: lower SymConst-Size and Sel nodes, Casts, unaligned Load/Stores. */
+	irg_walk_graph(irg, NULL, lower_irnode, NULL);
+
+	set_irg_outs_inconsistent(irg);
+}
+
+struct pass_t {
+	ir_graph_pass_t pass;
+	int            lower_bitfields;
+};
+
+/**
+ * Wrapper for running lower_highlevel_graph() as an ir_graph pass.
+ */
+static int lower_highlevel_graph_wrapper(ir_graph *irg, void *context)
+{
+	struct pass_t *pass = context;
+
+	lower_highlevel_graph(irg, pass->lower_bitfields);
+	return 0;
+}  /* lower_highlevel_graph_wrapper */
+
+ir_graph_pass_t *lower_highlevel_graph_pass(const char *name, int lower_bitfields)
+{
+	struct pass_t *pass = XMALLOCZ(struct pass_t);
+
+	pass->lower_bitfields = lower_bitfields;
+	return def_graph_pass_constructor(
+		&pass->pass, name ? name : "lower_hl", lower_highlevel_graph_wrapper);
+}  /* lower_highlevel_graph_pass */
+
+/*
+ * does the same as lower_highlevel() for all nodes on the const code irg
+ */
+void lower_const_code(void)
+{
+	walk_const_code(NULL, lower_irnode, NULL);
+}  /* lower_const_code */
+
+ir_prog_pass_t *lower_const_code_pass(const char *name)
+{
+	return def_prog_pass(name ? name : "lower_const_code", lower_const_code);
+}
 
 /*
  * Replaces SymConsts by a real constant if possible.
  * Replace Sel nodes by address computation.  Also resolves array access.
  * Handle Bitfields by added And/Or calculations.
  */
-void lower_highlevel(void) {
+void lower_highlevel(int lower_bitfields)
+{
 	int i, n;
 
 	n = get_irp_n_irgs();
 	for (i = 0; i < n; ++i) {
 		ir_graph *irg = get_irp_irg(i);
-
-		/* First step: lower bitfield access: must be run as long as Sels still exists. */
-		irg_walk_graph(irg, NULL, lower_bf_access, NULL);
-
-		/* Finally: lower SymConst-Size and Sel nodes. */
-		irg_walk_graph(irg, NULL, lower_irnode, NULL);
-
-		set_irg_phase_low(irg);
+		lower_highlevel_graph(irg, lower_bitfields);
 	}
+	lower_const_code();
 }  /* lower_highlevel */