add local and parameter rule

[r8581]

diff --git a/ir/ana/irmemory.c b/ir/ana/irmemory.c
index c764645..3c76a81 100644 (file)
--- a/ir/ana/irmemory.c
+++ b/ir/ana/irmemory.c
@@ -132,6 +132,20 @@ static ir_alias_relation different_types(ir_node *adr1, ir_node *adr2)
        return may_alias;
 }  /* different_types */
 
+/**
+ * Returns non-zero if a node is a routine parameter.
+ *
+ * @param node  the node to test
+ */
+static int is_arg_Proj(ir_node *node) {
+       if (! is_Proj(node))
+               return 0;
+       node = get_Proj_pred(node);
+       if (! is_Proj(node))
+               return 0;
+       return is_Start(get_Proj_pred(node) && pn_Start_T_args == get_Proj_proj(node));
+}  /* is_arg_Proj */
+
 /**
  * Determine the alias relation between two addresses.
  */
@@ -158,7 +172,7 @@ static ir_alias_relation _get_alias_relation(
 
        /* Two save some code, sort the addresses by its id's. Beware, this
           might break some things, so better check here. */
-       assert(iro_SymConst < iro_Sel && "Code dependence breaked");
+       assert(iro_SymConst < iro_Sel && iro_Sel < iro_Proj && "Code dependence breaked");
        op1 = get_irn_opcode(adr1);
        op2 = get_irn_opcode(adr2);
 
@@ -232,7 +246,14 @@ static ir_alias_relation _get_alias_relation(
                                        /* the second one is a TLS variable so they are always
                                       different (R1 d) */
                                        return no_alias;
+                               } else if (is_arg_Proj(base2)) {
+                                       /* the second one is an offset from a parameter so they are
+                                          always different (R1 e) */
+                                       return no_alias;
                                }
+                       } else if (is_arg_Proj(adr2)) {
+                               /* a local variable and a parameter are always different (R1 e) */
+                               return no_alias;
                        }
                } else if (base1 == get_irg_tls(irg)) {
                        /* the first is a TLS variable */
@@ -253,15 +274,27 @@ static ir_alias_relation _get_alias_relation(
                                                return different_offsets(adr1, adr2);
                                }
                        }
+               } else if (is_arg_Proj(base1)) {
+                       /* the first one is an offset from a parameter */
+                       if (is_Sel(adr2)) {
+                               /* the second address is a Sel */
+                               ir_node *base2 = find_base_adr(adr2, &ent2);
+
+                               if (base2 == get_irg_frame(irg)) {
+                                       /* the second one is a local variable so they are always
+                                      different (R1 e) */
+                                       return no_alias;
+                               }
+                       }
                }
        }
 
-       if (options & aa_opt_type_based) {
+       if (options & aa_opt_type_based) { /* Type based alias analysis */
                ir_alias_relation rel;
 
                if (options & aa_opt_byte_type_may_alias) {
                        if (get_mode_size_bits(mode1) == 8 || get_mode_size_bits(mode2) == 8) {
-                               /* One of the modes address a byte. Assume a may_alias ant leave
+                               /* One of the modes address a byte. Assume a may_alias and leave
                                   the type based check. */
                                goto leave_type_based_alias;
                        }

diff --git a/ir/ana/irmemory.h b/ir/ana/irmemory.h
index 794d7ba..7032634 100644 (file)
--- a/ir/ana/irmemory.h
+++ b/ir/ana/irmemory.h
@@ -61,6 +61,7 @@ typedef ir_alias_relation (*DISAMBIGUATOR_FUNC)(
  *   - a global variable and a local one never alias (R1 b)
  *   - a global variable and a TLS one never alias (R1 c)
  *   - a local variable and a TLS one never alias (R1 d)
+ *   - a local variable and a parameter never alias (R1 e)
  * - two different variables never alias (R2)
  * - if one is a variable which address has never taken
  *   there is no alias (R3)