PR middle-end/16790

	* fold-const.c (extract_muldiv_1) <NOP_EXPR>: Disallow local
	truncations, not just global truncations.

	* gcc.c-torture/execute/pr16790-1.c: New test case.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@85506 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 41 insertions, 0 deletions

diff --git a/gcc/testsuite/gcc.c-torture/execute/pr16790-1.c b/gcc/testsuite/gcc.c-torture/execute/pr16790-1.c
new file mode 100644
index 00000000000..dc6a77404b5
--- /dev/null
+++ b/gcc/testsuite/gcc.c-torture/execute/pr16790-1.c
@@ -0,0 +1,41 @@
+/* PR middle-end/16790.  */
+
+extern void abort ();
+
+static void test1(unsigned int u1)
+{
+  unsigned int y_final_1;
+  signed short y_middle;
+  unsigned int y_final_2;
+
+  y_final_1 = (unsigned int)( (signed short)(u1 * 2) * 3 );
+  y_middle  =                 (signed short)(u1 * 2);
+  y_final_2 = (unsigned int)( y_middle * 3 );
+
+  if (y_final_1 != y_final_2)
+    abort ();
+}
+
+
+static void test2(unsigned int u1)
+{
+  unsigned int y_final_1;
+  signed short y_middle;
+  unsigned int y_final_2;
+
+  y_final_1 = (unsigned int)( (signed short)(u1 << 1) * 3 );
+  y_middle  =                 (signed short)(u1 << 1);
+  y_final_2 = (unsigned int)( y_middle * 3 );
+
+  if (y_final_1 != y_final_2)
+    abort ();
+}
+
+
+int main()
+{
+  test1(0x4000U);
+  test2(0x4000U);
+  return 0;
+}
+