add return normalization to help same cases

moved Mux optimization code to iropt.c

[r5426]

diff --git a/ir/opt/ifconv.c b/ir/opt/ifconv.c
index dd93898..0c907d3 100644 (file)
--- a/ir/opt/ifconv.c
+++ b/ir/opt/ifconv.c
@@ -40,90 +40,9 @@
 #include "bitset.h"
 #include "bitfiddle.h"
 #include "irhooks.h"
+#include "return.h"
 
-#define MAX_DEPTH                              20
-
-/*
- * Mux optimization routines.
- */
-
-#if 0
-static ir_node *local_optimize_mux(ir_node *mux)
-{
-       int i, n;
-       ir_node *res = mux;
-  ir_node *sel = get_Mux_sel(mux);
-       ir_node *cmp = skip_Proj(sel);
-
-       /* Optimize the children  */
-       for(i = 1, n = get_irn_arity(mux); i < n; ++i) {
-               ir_node *operand = get_irn_n(mux, i);
-               if(get_irn_op(operand) == op_Mux)
-                       optimize_mux(operand);
-       }
-
-       /* If we have no cmp above the mux, get out. */
-       if(is_Proj(sel) && get_irn_mode(sel) == mode_b && get_irn_opcode(cmp) == iro_Cmp) {
-
-               pn_Cmp cc = get_Proj_proj(sel);
-               ir_mode *mode = get_irn_mode(mux);
-               ir_node *block = get_nodes_block(n);
-               ir_node *cmp_left = get_Cmp_left(cmp);
-               ir_node *cmp_right = get_Cmp_right(cmp);
-               ir_node *mux_true = get_Mux_true(mux);
-               ir_node *mux_false = get_Mux_false(mux);
-
-               /*
-                * Check for comparisons with signed integers.
-                */
-               if(mode_is_int(mode)                                    /* We need an integral mode */
-                               && mode_is_signed(mode)   /* which is signed */
-                               && cc == Lt) {                                          /* and have to compare for < */
-
-                       /*
-                        * Mux(x:T < 0, -1, 0) -> Shrs(x, sizeof_bits(T) - 1)
-                        * Conditions:
-                        * T must be signed.
-                        */
-                       if(classify_Const(cmp_right) == CNST_NULL
-                               && classify_Const(mux_true) == CNST_ALL_ONE
-                               && classify_Const(mux_false) == CNST_NULL) {
-
-                               ir_mode *u_mode = find_unsigned_mode(mode);
-
-                               res = new_r_Shrs(current_ir_graph, block, cmp_left,
-                                               new_r_Const_long(current_ir_graph, block, u_mode,
-                                                       get_mode_size_bits(mode) - 1),
-                                               mode);
-                       }
-
-                       /*
-                        * Mux(0 < x:T, 1, 0) -> Shr(-x, sizeof_bits(T) - 1)
-                        * Conditions:
-                        * T must be signed.
-                        */
-                       else if(classify_Const(cmp_left) == CNST_NULL
-                               && classify_Const(mux_true) == CNST_ONE
-                               && classify_Const(mux_false) == CNST_NULL) {
-
-                               ir_mode *u_mode = find_unsigned_mode(mode);
-
-                               res = new_r_Shr(current_ir_graph, block,
-
-                                               /* -x goes to 0 - x in Firm (cmp_left is 0, see the if) */
-                                               new_r_Sub(current_ir_graph, block, cmp_left, cmp_right, mode),
-
-                                               /* This is sizeof_bits(T) - 1 */
-                                               new_r_Const_long(current_ir_graph, block, u_mode,
-                                                       get_mode_size_bits(mode) - 1),
-                                               mode);
-                       }
-               }
-       }
-
-       return res;
-}
-#endif
+#define MAX_DEPTH                              4
 
 /**
  * check, if a node is const and return its tarval or
@@ -1002,6 +921,9 @@ void opt_if_conv(ir_graph *irg, opt_if_conv_info_t *params)
        firm_dbg_set_mask(dbg, LEVEL_1);
 #endif
 
+       /* if-conversion works better with normalized returns */
+       normalize_one_return(irg);
+
        /* Ensure, that the dominators are computed. */
        compute_doms(irg);