re PR ipa/78644 (ICE: SIGSEGV in is_gimple_reg_type with -Og -fipa-cp)

2017-03-28  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/78644
	* tree-ssa-ccp.c (evaluate_stmt): When we may not use the value
	of a simplification result we may not use it at all.

	* gcc.dg/pr78644-1.c: New testcase.
	* gcc.dg/pr78644-2.c: Likewise.

From-SVN: r246534

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index f15a8a882bb0b93cb6b3495a8345392eba0126ce..df901592ec97e61908776b521edc91fa4031d8af 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2017-03-28  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/78644
+       * tree-ssa-ccp.c (evaluate_stmt): When we may not use the value
+       of a simplification result we may not use it at all.
+
 2017-03-28  Richard Biener  <rguenther@suse.de>
 
        PR ipa/80205

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index e7b3f01d215a0ddec1e93ab08d009fd1d32fd656..0c0281e5f46ab4441c5b46385f89004d2117d4ef 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2017-03-28  Richard Biener  <rguenther@suse.de>
+
+       PR tree-optimization/78644
+       * gcc.dg/pr78644-1.c: New testcase.
+       * gcc.dg/pr78644-2.c: Likewise.
+
 2017-03-28  Toma Tabacu  <toma.tabacu@imgtec.com>
 
        * gcc.dg/pic-3.c: Skip for mips*-*-linux-*.

diff --git a/gcc/testsuite/gcc.dg/pr78644-1.c b/gcc/testsuite/gcc.dg/pr78644-1.c
new file mode 100644 (file)
index 0000000..d6aafeb
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr78644-1.c
@@ -0,0 +1,21 @@
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-Og -fipa-cp -w -Wno-psabi" } */
+
+typedef unsigned __int128 u128;
+typedef unsigned __int128 V __attribute__ ((vector_size (64)));
+
+V x4;
+
+static V
+bar (u128 x2, u128 x3)
+{
+  while (x4[0]--)
+    x2 /= x3 >>= 1;
+  return x2 + x3 + x4;
+}
+
+void
+foo (void)
+{
+  bar (0, 0);
+}

diff --git a/gcc/testsuite/gcc.dg/pr78644-2.c b/gcc/testsuite/gcc.dg/pr78644-2.c
new file mode 100644 (file)
index 0000000..3395dde
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr78644-2.c
@@ -0,0 +1,20 @@
+/* { dg-do compile { target int128 } } */
+/* { dg-options "-Og -finline-functions-called-once -w -Wno-psabi" } */
+
+typedef unsigned V __attribute__ ((vector_size (64)));
+typedef unsigned __int128 U __attribute__ ((vector_size (64)));
+
+U
+bar4 (U u0, U u1)
+{
+  if (u1[0])
+    u1 <<= 1;
+  return u0 + u1;
+}
+
+V
+foo (U u, V v)
+{
+  v |= (unsigned)bar4(u, (U){})[0];
+  return v;
+}

diff --git a/gcc/tree-ssa-ccp.c b/gcc/tree-ssa-ccp.c
index 023018c8d333bc2a43f25ea27b183613fc50cb88..23f2adcb9c48b47799019fedf33163dfaf22968b 100644 (file)
--- a/gcc/tree-ssa-ccp.c
+++ b/gcc/tree-ssa-ccp.c
@@ -1749,18 +1749,24 @@ evaluate_stmt (gimple *stmt)
       fold_defer_overflow_warnings ();
       simplified = ccp_fold (stmt);
       if (simplified
-         && TREE_CODE (simplified) == SSA_NAME
+         && TREE_CODE (simplified) == SSA_NAME)
+       {
          /* We may not use values of something that may be simulated again,
             see valueize_op_1.  */
-         && (SSA_NAME_IS_DEFAULT_DEF (simplified)
-             || ! prop_simulate_again_p (SSA_NAME_DEF_STMT (simplified))))
-       {
-         ccp_prop_value_t *val = get_value (simplified);
-         if (val && val->lattice_val != VARYING)
+         if (SSA_NAME_IS_DEFAULT_DEF (simplified)
+             || ! prop_simulate_again_p (SSA_NAME_DEF_STMT (simplified)))
            {
-             fold_undefer_overflow_warnings (true, stmt, 0);
-             return *val;
+             ccp_prop_value_t *val = get_value (simplified);
+             if (val && val->lattice_val != VARYING)
+               {
+                 fold_undefer_overflow_warnings (true, stmt, 0);
+                 return *val;
+               }
            }
+         else
+           /* We may also not place a non-valueized copy in the lattice
+              as that might become stale if we never re-visit this stmt.  */
+           simplified = NULL_TREE;
        }
       is_constant = simplified && is_gimple_min_invariant (simplified);
       fold_undefer_overflow_warnings (is_constant, stmt, 0);