From: Jakub Jelinek <jakub@redhat.com>
Date: Tue, 31 Mar 2020 09:06:43 +0000 (+0200)
Subject: fold-const: Fix division folding with vector operands [PR94412]
X-Git-Tag: embedded-9-2020q2~10
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=8f99f9e6ccec167a5ba67dcc08e6c14948595b82;p=thirdparty%2Fgcc.git

fold-const: Fix division folding with vector operands [PR94412]

The following testcase is miscompiled since 4.9, we treat unsigned
vector types as if they were signed and "optimize" negations across it.

2020-03-31  Marc Glisse  <marc.glisse@inria.fr>
	    Jakub Jelinek  <jakub@redhat.com>

	PR middle-end/94412
	* fold-const.c (fold_binary_loc) <case TRUNC_DIV_EXPR>: Use
	ANY_INTEGRAL_TYPE_P instead of INTEGRAL_TYPE_P.

	* gcc.c-torture/execute/pr94412.c: New test.

Co-authored-by: Marc Glisse <marc.glisse@inria.fr>
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index ed82d0694b83..e3e5d86275be 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,6 +1,15 @@
 2020-04-07  Jakub Jelinek  <jakub@redhat.com>
 
 	Backported from mainline
+	2020-03-31  Marc Glisse  <marc.glisse@inria.fr>
+		    Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/94412
+	* fold-const.c (fold_binary_loc) <case TRUNC_DIV_EXPR>: Use
+	ANY_INTEGRAL_TYPE_P instead of INTEGRAL_TYPE_P.
+
+2020-04-07  Jakub Jelinek  <jakub@redhat.com>
+
 	2020-03-30  Jakub Jelinek  <jakub@redhat.com>
 
 	PR target/93069
diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index c717f24501e3..64273c1c6bc5 100644
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -10376,11 +10376,11 @@ fold_binary_loc (location_t loc, enum tree_code code, tree type,
 
       /* Convert -A / -B to A / B when the type is signed and overflow is
 	 undefined.  */
-      if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
+      if ((!ANY_INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
 	  && TREE_CODE (op0) == NEGATE_EXPR
 	  && negate_expr_p (op1))
 	{
-	  if (INTEGRAL_TYPE_P (type))
+	  if (ANY_INTEGRAL_TYPE_P (type))
 	    fold_overflow_warning (("assuming signed overflow does not occur "
 				    "when distributing negation across "
 				    "division"),
@@ -10390,11 +10390,11 @@ fold_binary_loc (location_t loc, enum tree_code code, tree type,
 						    TREE_OPERAND (arg0, 0)),
 				  negate_expr (op1));
 	}
-      if ((!INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
+      if ((!ANY_INTEGRAL_TYPE_P (type) || TYPE_OVERFLOW_UNDEFINED (type))
 	  && TREE_CODE (arg1) == NEGATE_EXPR
 	  && negate_expr_p (op0))
 	{
-	  if (INTEGRAL_TYPE_P (type))
+	  if (ANY_INTEGRAL_TYPE_P (type))
 	    fold_overflow_warning (("assuming signed overflow does not occur "
 				    "when distributing negation across "
 				    "division"),
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index c32e6a86b8ba..0c09c9ee12f7 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,6 +1,11 @@
 2020-04-07  Jakub Jelinek  <jakub@redhat.com>
 
 	Backported from mainline
+	2020-03-31  Jakub Jelinek  <jakub@redhat.com>
+
+	PR middle-end/94412
+	* gcc.c-torture/execute/pr94412.c: New test.
+
 	2020-03-30  Jakub Jelinek  <jakub@redhat.com>
 
 	PR c++/94385
diff --git a/gcc/testsuite/gcc.c-torture/execute/pr94412.c b/gcc/testsuite/gcc.c-torture/execute/pr94412.c
new file mode 100644
index 000000000000..6c806bbd90ce
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr94412.c
@@ -0,0 +1,28 @@
+/* PR middle-end/94412 */
+
+typedef unsigned V __attribute__ ((__vector_size__ (sizeof (unsigned) * 2)));
+
+void
+foo (V *v, V *w)
+{
+  *w = -*v / 11;
+}
+
+void
+bar (V *v, V *w)
+{
+  *w = -18 / -*v;
+}
+
+int
+main ()
+{
+  V a = (V) { 1, 0 };
+  V b = (V) { 3, __INT_MAX__ };
+  V c, d;
+  foo (&a, &c);
+  bar (&b, &d);
+  if (c[0] != -1U / 11 || c[1] != 0 || d[0] != 0 || d[1] != -18U / -__INT_MAX__)
+    __builtin_abort ();
+  return 0;
+}