From: jakub <jakub@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Wed, 15 Oct 2008 06:43:19 +0000 (+0000)
Subject: 	PR tree-optimization/36881
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=54af7f7e3f0f38a4cd5667fda9fd9a68ad554df0;p=thirdparty%2Fgcc.git

	PR tree-optimization/36881
	* tree-switch-conversion.c (check_final_bb): For flag_pic, check
	that each value doesn't need runtime relocations, for !flag_pic
	check that each value is just a valid initializer constant.

	* gcc.dg/tree-ssa/pr36881.c: New test.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@141129 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 84625a1f2b1a..200958413d4c 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2008-10-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/36881
+	* tree-switch-conversion.c (check_final_bb): For flag_pic, check
+	that each value doesn't need runtime relocations, for !flag_pic
+	check that each value is just a valid initializer constant.
+
 2008-10-14  Richard Sandiford  <rdsandiford@googlemail.com>
 
 	* config/mips/mips.h (reg_class): Remove HI_AND_GR_REGS,
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 12090cc227de..731785cb5a9a 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2008-10-15  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/36881
+	* gcc.dg/tree-ssa/pr36881.c: New test.
+
 2008-10-14  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/37819
diff --git a/gcc/testsuite/gcc.dg/tree-ssa/pr36881.c b/gcc/testsuite/gcc.dg/tree-ssa/pr36881.c
new file mode 100644
index 000000000000..742dd9ddb4b5
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/pr36881.c
@@ -0,0 +1,23 @@
+/* PR tree-optimization/36881 */
+/* { dg-do compile { target fpic } } */
+/* { dg-options "-O2 -fpic -fdump-tree-switchconv-all" } */
+
+const char *foo (int i)
+{
+  const char *p;
+  switch (i)
+    {
+    case 0:
+    case 6: p = ""; break;
+    case 1:
+    case 7: p = "abc"; break;
+    case 2:
+    case 8: p = "def"; break;
+    default: p = "ghi"; break;
+    }
+  return p;
+}
+
+/* { dg-final { scan-assembler-not "CSWTCH" } } */
+/* { dg-final { scan-tree-dump "need runtime relocations" "switchconv" } } */
+/* { dg-final { cleanup-tree-dump "switchconv" } } */
diff --git a/gcc/tree-switch-conversion.c b/gcc/tree-switch-conversion.c
index e9757454f219..798cf1615694 100644
--- a/gcc/tree-switch-conversion.c
+++ b/gcc/tree-switch-conversion.c
@@ -296,12 +296,29 @@ check_final_bb (void)
 	{
 	  basic_block bb = gimple_phi_arg_edge (phi, i)->src;
 
-	  if ((bb == info.switch_bb
-	       || (single_pred_p (bb) && single_pred (bb) == info.switch_bb))
-	      && !is_gimple_ip_invariant (gimple_phi_arg_def (phi, i)))
+	  if (bb == info.switch_bb
+	      || (single_pred_p (bb) && single_pred (bb) == info.switch_bb))
 	    {
-	      info.reason = "   Non-invariant value from a case\n";
-	      return false; /* Non-invariant argument.  */
+	      tree reloc, val;
+
+	      val = gimple_phi_arg_def (phi, i);
+	      if (!is_gimple_ip_invariant (val))
+		{
+		  info.reason = "   Non-invariant value from a case\n";
+		  return false; /* Non-invariant argument.  */
+		}
+	      reloc = initializer_constant_valid_p (val, TREE_TYPE (val));
+	      if ((flag_pic && reloc != null_pointer_node)
+		  || (!flag_pic && reloc == NULL_TREE))
+		{
+		  if (reloc)
+		    info.reason
+		      = "   Value from a case would need runtime relocations\n";
+		  else
+		    info.reason
+		      = "   Value from a case is not a valid initializer\n";
+		  return false;
+		}
 	    }
 	}
     }