* simplify-rtx.c (simplify_plus_minus): Negate constant iff its neg

	field is different to previous argument's neg field.

	* gcc.c-torture/execute/20011019-1.c: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@46356 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 30b3685..7a8155b 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2001-10-19  Jakub Jelinek  <jakub@redhat.com>
+
+       * simplify-rtx.c (simplify_plus_minus): Negate constant iff its neg
+       field is different to previous argument's neg field.
+
 Fri Oct 19 15:24:39 2001  Richard Kenner  <kenner@vlsi1.ultra.nyu.edu>
 
        * final.c (get_decl_from_op): New function.

diff --git a/gcc/simplify-rtx.c b/gcc/simplify-rtx.c
index 2b7e3a2..bdeb265 100644 (file)
--- a/gcc/simplify-rtx.c
+++ b/gcc/simplify-rtx.c
@@ -1882,7 +1882,7 @@ simplify_plus_minus (code, mode, op0, op1)
       && CONSTANT_P (ops[n_ops - 2].op))
     {
       HOST_WIDE_INT value = INTVAL (ops[n_ops - 1].op);
-      if (ops[n_ops - 1].neg)
+      if (ops[n_ops - 1].neg ^ ops[n_ops - 2].neg)
        value = -value;
       ops[n_ops - 2].op = plus_constant (ops[n_ops - 2].op, value);
       n_ops--;

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 114fc4a..a59720d 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2001-10-19  Jakub Jelinek  <jakub@redhat.com>
+
+       * gcc.c-torture/execute/20011019-1.c: New test.
+
 2001-10-19  NIIBE Yutaka  <gniibe@m17n.org>
 
        * gcc.c-torture/execute/ieee/ieee.exp: Change sh-*-* to sh*-*-*.

diff --git a/gcc/testsuite/gcc.c-torture/execute/20011019-1.c b/gcc/testsuite/gcc.c-torture/execute/20011019-1.c
new file mode 100644 (file)
index 0000000..ebaa411
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/20011019-1.c
@@ -0,0 +1,18 @@
+extern void exit (int);
+extern void abort (void);
+
+struct { int a; int b[5]; } x;
+int *y;
+
+int foo (void)
+{
+  return y - x.b;
+}
+
+int main (void)
+{
+  y = x.b;
+  if (foo ())
+    abort ();
+  exit (0);
+}