From 18f22506bad9e3168b2c741c14af4b1a701fc6ee Mon Sep 17 00:00:00 2001
From: uz <uz@b7a2c559-68d2-44c3-8de9-860c34a00d81>
Date: Thu, 12 Jul 2012 21:11:21 +0000
Subject: [PATCH] Added a test program to test the 16 bit shift ops.

git-svn-id: svn://svn.cc65.org/cc65/trunk@5782 b7a2c559-68d2-44c3-8de9-860c34a00d81
---
 testcode/lib/shift-test.c | 136 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 136 insertions(+)
 create mode 100644 testcode/lib/shift-test.c

diff --git a/testcode/lib/shift-test.c b/testcode/lib/shift-test.c
new file mode 100644
index 000000000..5712f4534
--- /dev/null
+++ b/testcode/lib/shift-test.c
@@ -0,0 +1,136 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+
+
+
+static unsigned UnsignedShiftLeft1 (unsigned Val)
+/* Shift an unsigned left by 1 */
+{
+    __AX__ = Val;
+    asm ("stx tmp1");
+    asm ("asl a");
+    asm ("rol tmp1");
+    asm ("ldx tmp1");
+    return __AX__;
+}
+
+
+
+static unsigned UnsignedShiftRight1 (unsigned Val)
+/* Shift an unsigned right by 1 */
+{
+    __AX__ = Val;
+    asm ("stx tmp1");
+    asm ("lsr tmp1");
+    asm ("ror a");
+    asm ("ldx tmp1");
+    return __AX__;
+}
+
+
+
+static int SignedShiftRight1 (int Val)
+/* Shift a signed right by 1 */
+{
+    __AX__ = Val;
+    asm ("stx tmp1");
+    asm ("cpx #$80");
+    asm ("ror tmp1");
+    asm ("ror a");
+    asm ("ldx tmp1");
+    return __AX__;
+}
+
+
+
+static void TestUnsignedLeftShift (void)
+/* Test left shift. This is identical for signed and unsigned ints */
+{
+    unsigned L, R, V;
+    printf ("Testing unsigned left shift:\n");
+    L = 0;
+    do {
+        V = L;
+        for (R = 0; R < 16; ++R) {
+            /* Check it */
+            if ((L << R) != V) {
+                fprintf (stderr,
+                         "Failed: %u << %u != %u (%u)\n",
+                         L, R, V, L << R);
+                exit (1);
+            }
+            V = UnsignedShiftLeft1 (V);
+        }
+        if ((L & 0xFF) == 0) {
+            printf ("%04X ", L);
+        }
+    } while (++L != 0);
+    printf ("\n");
+}
+
+
+
+static void TestUnsignedRightShift (void)
+/* Test unsigned right shift. */
+{
+    unsigned L, R, V;
+    printf ("Testing unsigned right shift:\n");
+    L = 0;
+    do {
+        V = L;
+        for (R = 0; R < 16; ++R) {
+            /* Check it */
+            if ((L >> R) != V) {
+                fprintf (stderr,
+                         "Failed: %u >> %u != %u (%u)\n",
+                         L, R, V, L >> R);
+                exit (1);
+            }
+            V = UnsignedShiftRight1 (V);
+        }
+        if ((L & 0xFF) == 0) {
+            printf ("%04X ", L);
+        }
+    } while (++L != 0);
+    printf ("\n");
+}
+
+
+
+static void TestSignedRightShift (void)
+/* Test signed right shift. */
+{
+    int L, R, V;
+    printf ("Testing signed right shift:\n");
+    L = 0;
+    do {
+        V = L;
+        for (R = 0; R < 16; ++R) {
+            /* Check it */
+            if ((L >> R) != V) {
+                fprintf (stderr,
+                         "Failed: %d >> %d != %d (%d)\n",
+                         L, R, V, L >> R);
+                exit (1);
+            }
+            V = SignedShiftRight1 (V);
+        }
+        if ((L & 0xFF) == 0) {
+            printf ("%04X ", L);
+        }
+    } while (++L != 0);
+    printf ("\n");
+}
+
+
+
+int main (void)
+{
+    TestUnsignedLeftShift ();
+    TestUnsignedRightShift ();
+    TestSignedRightShift ();
+    printf ("\nOk!\n");
+
+    return 0;
+}