contrib/gcc/tree-ssa-phiopt.c

61       if (cond) goto bb2; else goto bb1;
62      bb1:
64       x = PHI <0 (bb1), 1 (bb0), ...>;
74    We remove bb1 as it becomes unreachable.  This occurs often due to
83        if (a != b) goto bb2; else goto bb1;
84      bb1:
86        x = PHI <a (bb1), b (bb0), ...>;
103        if (a >= 0) goto bb2; else goto bb1;
104      bb1:
107        x = PHI <x (bb1), a (bb0), ...>;
122        if (a <= b) goto bb2; else goto bb1;
123      bb1:
125        x = PHI <b (bb1), a (bb0), ...>;
158       basic_block bb1, bb2;
171       bb1 = e1->dest;
180       /* If either bb1's succ or bb2 or bb2's succ is non NULL.  */
181       if (EDGE_COUNT (bb1->succs) == 0
187       if (EDGE_SUCC (bb1, 0)->dest == bb2)
189       else if (EDGE_SUCC (bb2, 0)->dest == bb1)
191 	  basic_block bb_tmp = bb1;
193 	  bb1 = bb2;
201       e1 = EDGE_SUCC (bb1, 0);
203       /* Make sure that bb1 is just a fall through.  */
204       if (!single_succ_p (bb1)
208       /* Also make sure that bb1 only have one predecessor and that it
210       if (!single_pred_p (bb1)
211           || single_pred (bb1) != bb)
230       if (conditional_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
232       else if (value_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
234       else if (abs_replacement (bb, bb1, e1, e2, phi, arg0, arg1))
236       else if (minmax_replacement (bb, bb1, e1, e2, phi, arg0, arg1))