[PATCH] Fix up gimplify_and_update_call_from_tree (PR tree-optimization/52318)

[Jakub Jelinek]

Hi!

This function spends significant amount of code to update the virtual
uses/defs in the new sequence, but only handles that way stores, not
non-pure/const calls, so we ICE during tree DSE on this testcase, because
vop has been marked for renaming.

Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok
for trunk?

2012-02-20  Jakub Jelinek  <ja...@redhat.com>

        PR tree-optimization/52318
        * gimple-fold.c (gimplify_and_update_call_from_tree): Add
        vdef also to non-pure/const call stmts in the sequence.

        * gcc.dg/pr52318.c: New test.

--- gcc/gimple-fold.c.jj        2011-12-16 08:37:45.000000000 +0100
+++ gcc/gimple-fold.c   2012-02-20 21:51:20.853133362 +0100
@@ -591,8 +591,11 @@ gimplify_and_update_call_from_tree (gimp
   for (i = gsi_last (stmts); !gsi_end_p (i); gsi_prev (&i))
     {
       new_stmt = gsi_stmt (i);
-      if (gimple_assign_single_p (new_stmt)
-         && !is_gimple_reg (gimple_assign_lhs (new_stmt)))
+      if ((gimple_assign_single_p (new_stmt)
+          && !is_gimple_reg (gimple_assign_lhs (new_stmt)))
+         || (is_gimple_call (new_stmt)
+             && (gimple_call_flags (new_stmt)
+                 & (ECF_NOVOPS | ECF_PURE | ECF_CONST | ECF_NORETURN)) == 0))
        {
          tree vdef;
          if (!laststore)
--- gcc/testsuite/gcc.dg/pr52318.c.jj   2012-02-20 22:10:09.211778710 +0100
+++ gcc/testsuite/gcc.dg/pr52318.c      2012-02-20 22:09:10.000000000 +0100
@@ -0,0 +1,17 @@
+/* PR tree-optimization/52318 */
+/* { dg-do compile } */
+/* { dg-options "-O3 -ftracer -fno-tree-ccp -fno-tree-copy-prop -fno-tree-dce" 
} */
+
+int c;
+char *p;
+
+void
+foo (int i)
+{
+  char a[2];
+  char b[20];
+  p = __builtin___stpcpy_chk (a, "", 2);
+  p = __builtin___stpcpy_chk (&b[16], i ? "e" : "jkl", 4);
+  if (c)
+    foo (i);
+}

        Jakub