From ca25e0e1b818b48a33e96bba668d439abc06ad33 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Thu, 11 Oct 2018 13:17:11 +0100
Subject: [PATCH] more explicit testing, duplicating header file algorithms for
 div, rem and shift

---
 operators/operators.t.cc | 106 +++++++++++++++++++++++++++++++++++----
 1 file changed, 96 insertions(+), 10 deletions(-)

diff --git a/operators/operators.t.cc b/operators/operators.t.cc
index c025c49..3ad5c68 100644
--- a/operators/operators.t.cc
+++ b/operators/operators.t.cc
@@ -12,19 +12,27 @@
 #define plus +
 #define minus -
 #define shiftr >>
-#define shiftl >>
-#define mul >>
+#define shiftl <<
+#define mul *
+
+#define xlen 64
+
+#define zext(x, y) (((reg_t)(x) << (64-y)) >> (64-y))
+//typedef int64_t sreg_t;
+//#define sext32(x) ((sreg_t)(int32_t)(x))
+
 
 #define operator_check( op ) { \
-            int8_t z = x op y;                                \
+            int8_t z = (int8_t)(x op y);                       \
             x1 = (uint8_t)x;                                  \
             y1 = (uint8_t)y;                                  \
-            uint16_t z1 = x1 op y1;                           \
+            uint64_t z1 = x1 op y1;                           \
             if ((uint8_t)z1 != (uint8_t)z) {                  \
-                printf("FAILED %s %d %d %d %d\n",             \
+                printf("FAILED %s %d %d %d %ld\n",             \
                     xstr(op), i, j, z, z1);                   \
             }                                                 \
             }
+
 int main(int argc, char *argv[])
 {
     /*op2<uint16_t, uint16_t, uint32_t> o(0xfff0);
@@ -39,7 +47,7 @@ int main(int argc, char *argv[])
     //printf("hello %lx\n", o);
 
     int8_t x=0, y=0;
-    int16_t x1, y1;
+    uint64_t x1, y1;
 
     for (int i=0, x=0; i < 256; i++, x++) {
         //printf("hello %x\n", (int)(uint8_t)x);
@@ -47,10 +55,88 @@ int main(int argc, char *argv[])
             operator_check( plus )
             operator_check( minus )
             operator_check( mul )
-            operator_check( divide )
-            operator_check( remainder )
-            operator_check( shiftr )
-            operator_check( shiftl )
+
+            // shiftl - NOTE: must use xlen=8.  so, have to overload xlen...
+            {
+                int8_t z = 0;
+                z = (int8_t)(x << (y & (8-1)));
+                x1 = (uint8_t)x;
+                y1 = (uint8_t)y;
+                uint64_t z1 = (x1 << (y1 & (8-1)));
+                if ((uint8_t)z1 != (uint8_t)z) {
+                    printf("FAILED %s xy %d %d x1y1 %d %d z %d z1 %ld\n",
+                        "<<", x, y, x1, y1, z, z1);
+                }
+                else {
+                    printf("OK %s %d %d %d %ld\n",
+                        "<<", x, y, z, z1);
+                }
+            }
+            // shiftr
+            {
+                int8_t z = 0;
+                z = (int8_t)(zext(x, 8) >> (y & (8-1)));
+                x1 = (uint8_t)x;
+                y1 = (uint8_t)y;
+                uint64_t z1 = (zext(x1, 8) >> (y1 & (8-1)));
+                if ((uint8_t)z1 != (uint8_t)z) {
+                    printf("FAILED %s xy %d %d x1y1 %ld %ld z %d z1 %ld\n",
+                        ">>", x, y, x1, y1, z, z1);
+                }
+                else {
+                    printf("OK %s %d %d %d %ld\n",
+                        ">>", x, y, z, z1);
+                }
+            }
+            // rem
+            {
+                int8_t z = 0;
+                if (y == 0)
+                    z = sext32(y);
+                else
+                    z = (int8_t)(x % y);
+                x1 = (uint8_t)x;
+                y1 = (uint8_t)y;
+                uint64_t z1 = 0;
+                if (y1 == 0)
+                    z1 = sext32(y1);
+                    z1 = (x1 % y1);
+                if ((uint8_t)z1 != (uint8_t)z) {
+                    printf("FAILED %s xy %d %d x1y1 %d %d z %d z1 %ld\n",
+                        "rem", x, y, x1, y1, z, z1);
+                }
+                else {
+                    printf("OK %s %d %d %d %ld\n",
+                        "rem", x, y, z, z1);
+                }
+            }
+            // divide
+            {
+                int8_t z = 0;
+                if (y == 0)
+                    z = 0xff;
+                else if (x == -127 && y == -1) // have to redefine UINT64_MAX
+                    z = x;
+                else
+                    z = (int8_t)(x / y);
+                x1 = (uint8_t)x;
+                y1 = (uint8_t)y;
+                uint64_t z1 = 0;
+                if (y1 == 0)
+                    z1 = UINT64_MAX;
+                else if (x1 == INT64_MIN && y1 == -1)
+                    z1 = x1;
+                else
+                    z1 = (x1 / y1);
+                if ((uint8_t)z1 != (uint8_t)z) {
+                    printf("FAILED %s xy %d %d x1y1 %ld %ld z %d z1 %ld\n",
+                        xstr(op), x, y, x1, y1, z, z1);
+                }
+                else {
+                    printf("OK %s %d %d %d %ld\n",
+                        xstr(op), x, y, z, z1);
+                }
+            }
         }
     }
 }
-- 
2.30.2