X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fir%2Firarch.c;h=ada45d670d5b47f0eeb34d9d35636895152ae7e6;hb=672b5c243e900427b5dcae01441d4fa3327d692c;hp=2431931a6f4f90efedb64d987a6e00cfea405daf;hpb=bdacbd77db4138f76e06dde1f0098edfa25e1aa9;p=libfirm

diff --git a/ir/ir/irarch.c b/ir/ir/irarch.c
index 2431931a6..ada45d670 100644
--- a/ir/ir/irarch.c
+++ b/ir/ir/irarch.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.
  *
@@ -79,9 +79,6 @@ void arch_dep_init(arch_dep_params_factory_t factory) {
 
 void arch_dep_set_opts(arch_dep_opts_t the_opts) {
 	opts = the_opts;
-
-	if (opts & arch_dep_mul_to_shift)
-		set_opt_arch_dep_running(1);
 }
 
 /** check, whether a mode allows a Mulh instruction. */
@@ -232,8 +229,8 @@ static unsigned char *value_to_condensed(mul_env *env, tarval *tv, int *pr) {
  * Calculate the gain when using the generalized complementary technique
  */
 static int calculate_gain(unsigned char *R, int r) {
-	int max_gain = -1;
-	int idx, i;
+	int max_gain = 0;
+	int idx = -1, i;
 	int gain;
 
 	/* the gain for r == 1 */
@@ -247,9 +244,7 @@ static int calculate_gain(unsigned char *R, int r) {
 			idx = i;
 		}
 	}
-	if (max_gain > 0)
-		return idx;
-	return -1;
+	return idx;
 }
 
 /**
@@ -329,11 +324,16 @@ static instruction *decompose_simple_cases(mul_env *env, unsigned char *R, int r
 		assert(r == 2);
 
 		ins = env->root;
+		if (R[1] <= env->max_S) {
+			ins = emit_LEA(env, ins, ins, R[1]);
+			if (R[0] != 0) {
+				ins = emit_SHIFT(env, ins, R[0]);
+			}
+			return ins;
+		}
 		if (R[0] != 0) {
 			ins = emit_SHIFT(env, ins, R[0]);
 		}
-		if (R[1] <= env->max_S)
-			return emit_LEA(env, ins, ins, R[1]);
 
 		ins2 = emit_SHIFT(env, env->root, R[0] + R[1]);
 		return emit_LEA(env, ins, ins2, 0);
@@ -570,30 +570,34 @@ ir_node *arch_dep_replace_mul_with_shifts(ir_node *irn) {
 	if (params == NULL || (opts & arch_dep_mul_to_shift) == 0)
 		return irn;
 
-	if (is_Mul(irn) && mode_is_int(mode)) {
-		ir_node *left    = get_binop_left(irn);
-		ir_node *right   = get_binop_right(irn);
-		tarval *tv       = NULL;
-		ir_node *operand = NULL;
-
-		/* Look, if one operand is a constant. */
-		if (is_Const(left)) {
-			tv = get_Const_tarval(left);
-			operand = right;
-		} else if (is_Const(right)) {
-			tv = get_Const_tarval(right);
-			operand = left;
-		}
+	set_arch_dep_running(1);
+	{
+		if (is_Mul(irn) && mode_is_int(mode)) {
+			ir_node *left    = get_binop_left(irn);
+			ir_node *right   = get_binop_right(irn);
+			tarval *tv       = NULL;
+			ir_node *operand = NULL;
+
+			/* Look, if one operand is a constant. */
+			if (is_Const(left)) {
+				tv = get_Const_tarval(left);
+				operand = right;
+			} else if (is_Const(right)) {
+				tv = get_Const_tarval(right);
+				operand = left;
+			}
 
-		if (tv != NULL) {
-			res = do_decomposition(irn, operand, tv);
+			if (tv != NULL) {
+				res = do_decomposition(irn, operand, tv);
 
-			if (res != irn) {
-				hook_arch_dep_replace_mul_with_shifts(irn);
-				exchange(irn, res);
+				if (res != irn) {
+					hook_arch_dep_replace_mul_with_shifts(irn);
+					exchange(irn, res);
+				}
 			}
 		}
 	}
+	//set_arch_dep_running(0);
 
 	return res;
 }
@@ -926,15 +930,20 @@ ir_node *arch_dep_replace_div_by_const(ir_node *irn) {
 				ir_node *k_node;
 				ir_node *curr = left;
 
-				if (k != 1) {
-					k_node = new_r_Const_long(current_ir_graph, block, mode_Iu, k - 1);
-					curr   = new_rd_Shrs(dbg, current_ir_graph, block, left, k_node, mode);
-				}
+				/* create the correction code for signed values only if there might be a remainder */
+				if (! is_Div_remainderless(irn)) {
+					if (k != 1) {
+						k_node = new_r_Const_long(current_ir_graph, block, mode_Iu, k - 1);
+						curr   = new_rd_Shrs(dbg, current_ir_graph, block, left, k_node, mode);
+					}
 
-				k_node = new_r_Const_long(current_ir_graph, block, mode_Iu, bits - k);
-				curr   = new_rd_Shr(dbg, current_ir_graph, block, curr, k_node, mode);
+					k_node = new_r_Const_long(current_ir_graph, block, mode_Iu, bits - k);
+					curr   = new_rd_Shr(dbg, current_ir_graph, block, curr, k_node, mode);
 
-				curr   = new_rd_Add(dbg, current_ir_graph, block, left, curr, mode);
+					curr   = new_rd_Add(dbg, current_ir_graph, block, left, curr, mode);
+				} else {
+					k_node = left;
+				}
 
 				k_node = new_r_Const_long(current_ir_graph, block, mode_Iu, k);
 				res    = new_rd_Shrs(dbg, current_ir_graph, block, curr, k_node, mode);