[PATCH, PR 51583] One more missing force_gimple_operand in SRA

[Martin Jambor <mjambor at suse dot cz>]

Hi,

when I was fixing PR 50622, somehow I lost a hunk in the patch along
the way.  I punished myself by making up an ICEing testcase which is
included alongside the fix below.  The fix is needed for trunk and
also in the 4.6 branch.

I have bootstrapped and tested the patch on x86_64-linux on top of
trunk without any problems, a bootstrap and testsuite run on top of
the 4.6 branch is currently running.  OK for both if it passes?

Thanks,

Martin


2011-12-16  Martin Jambor  <mjambor@suse.cz>

	PR tree-optimization/51583
	* tree-sra.c (load_assign_lhs_subreplacements): Call
	force_gimple_operand_gsi when necessary also in case of no
	corresponding replacement on the RHS.

	* testsuite/gcc.dg/tree-ssa/pr51583.c: New test.

Index: src/gcc/tree-sra.c
===================================================================
--- src.orig/gcc/tree-sra.c
+++ src/gcc/tree-sra.c
@@ -2752,6 +2752,9 @@ load_assign_lhs_subreplacements (struct
 	      else
 		rhs = build_ref_for_model (loc, top_racc->base, offset, lacc,
 					    new_gsi, true);
+	      if (lacc->grp_partial_lhs)
+		rhs = force_gimple_operand_gsi (new_gsi, rhs, true, NULL_TREE,
+						false, GSI_NEW_STMT);
 	    }
 
 	  stmt = gimple_build_assign (get_access_replacement (lacc), rhs);
Index: src/gcc/testsuite/gcc.dg/tree-ssa/pr51583.c
===================================================================
--- /dev/null
+++ src/gcc/testsuite/gcc.dg/tree-ssa/pr51583.c
@@ -0,0 +1,34 @@
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+
+typedef __complex__ double Value;
+
+union U
+{
+  Value v;
+  char c[sizeof(Value)];
+};
+
+struct S
+{
+  union U u;
+  int i,j;
+};
+
+Value gv;
+int gi, gj;
+
+Value foo (void)
+{
+  struct S s,t;
+
+  t.i = gi;
+  t.j = gj;
+  t.u.v = gv;
+  t.u.c[0] = 0;
+
+  s = t;
+  __imag__ s.u.v += s.i;
+
+  return s.u.v;
+}