range-op: Handle op?.undefined_p () in op[12]_range of comparisons [PR108647]

As mentioned in the PR, we ICE because lhs is singleton [0, 0]
or [1, 1] but op2 (or in other cases op1) is undefined and op?.*_bound ()
ICEs on those because there are no pairs for UNDEFINED.

The following patch makes us set r to varying or return false in those
cases.

2023-02-03  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/108647
	* range-op.cc (operator_equal::op1_range,
	operator_not_equal::op1_range): Don't test op2 bound
	equality if op2.undefined_p (), instead set_varying.
	(operator_lt::op1_range, operator_le::op1_range,
	operator_gt::op1_range, operator_ge::op1_range): Return false if
	op2.undefined_p ().
	(operator_lt::op2_range, operator_le::op2_range,
	operator_gt::op2_range, operator_ge::op2_range): Return false if
	op1.undefined_p ().

	* g++.dg/torture/pr108647.C: New test.

2 files changed, 53 insertions, 2 deletions

diff --git a/gcc/range-op.cc b/gcc/range-op.cc
index 136b709..5c67bce 100644
--- a/gcc/range-op.cc
+++ b/gcc/range-op.cc
@@ -642,7 +642,8 @@ operator_equal::op1_range (irange &r, tree type,
     case BRS_FALSE:
       // If the result is false, the only time we know anything is
       // if OP2 is a constant.
-      if (wi::eq_p (op2.lower_bound(), op2.upper_bound()))
+      if (!op2.undefined_p ()
+	  && wi::eq_p (op2.lower_bound(), op2.upper_bound()))
 	{
 	  r = op2;
 	  r.invert ();
@@ -755,7 +756,8 @@ operator_not_equal::op1_range (irange &r, tree type,
     case BRS_TRUE:
       // If the result is true, the only time we know anything is if
       // OP2 is a constant.
-      if (wi::eq_p (op2.lower_bound(), op2.upper_bound()))
+      if (!op2.undefined_p ()
+	  && wi::eq_p (op2.lower_bound(), op2.upper_bound()))
 	{
 	  r = op2;
 	  r.invert ();
@@ -920,6 +922,9 @@ operator_lt::op1_range (irange &r, tree type,
 			const irange &op2,
 			relation_trio) const
 {
+  if (op2.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -942,6 +947,9 @@ operator_lt::op2_range (irange &r, tree type,
 			const irange &op1,
 			relation_trio) const
 {
+  if (op1.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -1031,6 +1039,9 @@ operator_le::op1_range (irange &r, tree type,
 			const irange &op2,
 			relation_trio) const
 {
+  if (op2.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -1053,6 +1064,9 @@ operator_le::op2_range (irange &r, tree type,
 			const irange &op1,
 			relation_trio) const
 {
+  if (op1.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -1141,6 +1155,9 @@ operator_gt::op1_range (irange &r, tree type,
 			const irange &lhs, const irange &op2,
 			relation_trio) const
 {
+  if (op2.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -1163,6 +1180,9 @@ operator_gt::op2_range (irange &r, tree type,
 			const irange &op1,
 			relation_trio) const
 {
+  if (op1.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -1252,6 +1272,9 @@ operator_ge::op1_range (irange &r, tree type,
 			const irange &op2,
 			relation_trio) const
 {
+  if (op2.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
@@ -1274,6 +1297,9 @@ operator_ge::op2_range (irange &r, tree type,
 			const irange &op1,
 			relation_trio) const
 {
+  if (op1.undefined_p ())
+    return false;
+
   switch (get_bool_state (r, lhs, type))
     {
     case BRS_TRUE:
diff --git a/gcc/testsuite/g++.dg/torture/pr108647.C b/gcc/testsuite/g++.dg/torture/pr108647.C
new file mode 100644
index 0000000..abdb92a8
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr108647.C
@@ -0,0 +1,25 @@
+// PR tree-optimization/108647
+// { dg-do compile }
+
+bool a;
+int b, c;
+
+inline const bool &
+foo (bool &e, const bool &f)
+{
+  return f < e ? f : e;
+}
+
+void
+bar (signed char e, bool *f, bool *h, bool *g)
+{
+  for (;;)
+    if (g)
+      for (signed char j = 0; j < 6;
+	   j += ((f[0] & c ? g[0] : int(0 >= e))
+		 ? 0 : foo (g[0], g[0] > h[0]) + 1))
+	{
+	  a = 0;
+	  b = 0;
+	}
+}