tree-optimization/106938 - cleanup abnormal edges after inlining

After inlining and IPA transforms we run fixup_cfg to fixup CFG
effects in other functions.  But that fails to clean abnormal
edges from non-pure/const calls which might no longer be necessary
when ->calls_setjmp is false.  The following ensures this happens
and refactors things so we call EH/abnormal cleanup only on the
last stmt in a block.

	PR tree-optimization/106938
	* tree-cfg.cc (execute_fixup_cfg): Purge dead abnormal
	edges for all last stmts in a block.  Do EH cleanup
	only on the last stmt in a block.

	* gcc.dg/pr106938.c: New testcase.

diff --git a/gcc/testsuite/gcc.dg/pr106938.c b/gcc/testsuite/gcc.dg/pr106938.c
new file mode 100644 (file)
index 0000000..7365a8c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr106938.c
@@ -0,0 +1,36 @@
+/* { dg-do compile } */
+/* { dg-options "-O1 -fno-ipa-pure-const -fno-tree-ccp -Wuninitialized" } */
+
+int n;
+
+void
+undefined (void);
+
+__attribute__ ((returns_twice)) int
+zero (void)
+{
+  return 0;
+}
+
+void
+bar (int)
+{
+  int i;
+
+  for (i = 0; i < -1; ++i)
+    n = 0;
+}
+
+__attribute__ ((simd)) void
+foo (void)
+{
+  int uninitialized;
+
+  undefined ();
+
+  while (uninitialized < 1) /* { dg-warning "uninitialized" } */
+    {
+      bar (zero ());
+      ++uninitialized;
+    }
+}

diff --git a/gcc/tree-cfg.cc b/gcc/tree-cfg.cc
index 41ce1b29d177639783a751ae96d3624aa3496a98..53be0c2ec5df5e77c11e8efb9ba807350c87bf42 100644 (file)
--- a/gcc/tree-cfg.cc
+++ b/gcc/tree-cfg.cc
@@ -9836,16 +9836,12 @@ execute_fixup_cfg (void)
              int flags = gimple_call_flags (stmt);
              if (flags & (ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE))
                {
-                 if (gimple_purge_dead_abnormal_call_edges (bb))
-                   todo |= TODO_cleanup_cfg;
-
                  if (gimple_in_ssa_p (cfun))
                    {
                      todo |= TODO_update_ssa | TODO_cleanup_cfg;
                      update_stmt (stmt);
                    }
                }
-
              if (flags & ECF_NORETURN
                  && fixup_noreturn_call (stmt))
                todo |= TODO_cleanup_cfg;
@@ -9875,10 +9871,15 @@ execute_fixup_cfg (void)
                }
            }
 
-         if (maybe_clean_eh_stmt (stmt)
+         gsi_next (&gsi);
+       }
+      if (gimple *last = last_stmt (bb))
+       {
+         if (maybe_clean_eh_stmt (last)
              && gimple_purge_dead_eh_edges (bb))
            todo |= TODO_cleanup_cfg;
-         gsi_next (&gsi);
+         if (gimple_purge_dead_abnormal_call_edges (bb))
+           todo |= TODO_cleanup_cfg;
        }
 
       /* If we have a basic block with no successors that does not