re PR tree-optimization/84960 (ICE in GIMPLE pass: isolate-paths)

	PR tree-optimization/84960
	* tree-cfg.c (remove_bb): Don't move forced labels into bb->prev_bb
	if it is ENTRY block, move them into single succ of ENTRY in that case.

	* gcc.c-torture/compile/pr84960.c: New test.

From-SVN: r258744

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 2c5ed01..eeab1f1 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2018-03-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR tree-optimization/84960
+       * tree-cfg.c (remove_bb): Don't move forced labels into bb->prev_bb
+       if it is ENTRY block, move them into single succ of ENTRY in that case.
+
 2018-03-21  Richard Sandiford  <richard.sandiford@linaro.org>
 
        PR tree-optimization/84811

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 36e1626..faf418d 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2018-03-21  Jakub Jelinek  <jakub@redhat.com>
+
+       PR tree-optimization/84960
+       * gcc.c-torture/compile/pr84960.c: New test.
+
 2018-03-21  Richard Sandiford  <richard.sandiford@linaro.org>
 
        PR tree-optimization/84811

diff --git a/gcc/testsuite/gcc.c-torture/compile/pr84960.c b/gcc/testsuite/gcc.c-torture/compile/pr84960.c
new file mode 100644 (file)
index 0000000..b076f79
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/compile/pr84960.c
@@ -0,0 +1,17 @@
+/* PR tree-optimization/84960 */
+/* { dg-do compile { target indirect_jumps } } */
+
+void
+foo (unsigned int a, float b, void *c)
+{
+lab:
+  if ((b - (a %= 0) < 1U) * -1U)
+    ;
+  else
+    {
+      unsigned int f = a;
+      __builtin_unreachable ();
+      c = &&lab;
+    }
+  goto *c;
+}

diff --git a/gcc/tree-cfg.c b/gcc/tree-cfg.c
index b87e48d..9485f73 100644 (file)
--- a/gcc/tree-cfg.c
+++ b/gcc/tree-cfg.c
@@ -2301,6 +2301,12 @@ remove_bb (basic_block bb)
                }
 
              new_bb = bb->prev_bb;
+             /* Don't move any labels into ENTRY block.  */
+             if (new_bb == ENTRY_BLOCK_PTR_FOR_FN (cfun))
+               {
+                 new_bb = single_succ (new_bb);
+                 gcc_assert (new_bb != bb);
+               }
              new_gsi = gsi_start_bb (new_bb);
              gsi_remove (&i, false);
              gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);