(if_then_else_cond): Call copy_rtx to prevent sharing.

From-SVN: r13736

diff --git a/gcc/combine.c b/gcc/combine.c
index 89f6525..2832871 100644 (file)
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6512,6 +6512,14 @@ if_then_else_cond (x, ptrue, pfalse)
       if ((cond0 != 0 || cond1 != 0)
          && ! (cond0 != 0 && cond1 != 0 && ! rtx_equal_p (cond0, cond1)))
        {
+         /* If if_then_else_cond returned zero, then true/false are the
+            same rtl.  We must copy one of them to prevent invalid rtl
+            sharing.  */
+         if (cond0 == 0)
+           true0 = copy_rtx (true0);
+         else if (cond1 == 0)
+           true1 = copy_rtx (true1);
+
          *ptrue = gen_binary (code, mode, true0, true1);
          *pfalse = gen_binary (code, mode, false0, false1);
          return cond0 ? cond0 : cond1;