[GR-23373] Again: Fix rshift of int/long with large right operand.

PullRequest: graalpython/964

Author: fangerer

graalpython/com.oracle.graal.python.test/src/tests/test_binary_arithmetic.py

@@ -275,4 +275,18 @@ def test_sub():
 
 def test_rshift():
     assert 1 >> 64 == 0
-    assert 0xffffffffffff >> 128 == 0
+    assert 0xffffffffffff >> 128 == 0
+    assert 0x7fffffec >> 24 == 0x7f
+    assert 0x7fffffec >> 32 == 0
+    assert 0x7fffffffffffffec >> 64 == 0
+    bigint = 0xffffffffffffffffffffffffffffffff
+    assert bigint >> 120 == 0xff
+    assert bigint >> 128 == 0
+    trimmed = bigint & 0x7fffffffffffffff
+    assert trimmed >> 64 == 0
+
+
+def test_lshift():
+    assert 1 << 32 == 0x100000000
+    assert 1 << 64 == 0x10000000000000000
+    assert 1 << 128 == 0x100000000000000000000000000000000

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/builtins/objects/ints/IntBuiltins.java

@@ -1214,7 +1214,7 @@ private void raiseNegativeShiftCount(boolean cond) {
     @TypeSystemReference(PythonArithmeticTypes.class)
     @GenerateNodeFactory
     abstract static class RShiftNode extends PythonBinaryBuiltinNode {
-        @Specialization(guards = "right < 64")
+        @Specialization(guards = "right < 32")
         int doIISmall(int left, int right) {
             raiseNegativeShiftCount(right < 0);
             return left >> right;
@@ -1225,10 +1225,10 @@ int doII(int left, int right) {
             raiseNegativeShiftCount(right < 0);
             // Note: according to JLS, if 'left' is an int, then only the 5 LSBs of 'right' are
             // considered. However, Python would consider more bits, so do the max possible shift.
-            return left >> (right >= 64 ? 63 : right);
+            return left >> (right >= 32 ? 31 : right);
         }
 
-        @Specialization(guards = "right < 128")
+        @Specialization(guards = "right < 64")
         long doLLSmall(long left, long right) {
             raiseNegativeShiftCount(right < 0);
             return left >> right;
@@ -1238,7 +1238,7 @@ long doLLSmall(long left, long right) {
         long doLL(long left, long right) {
             raiseNegativeShiftCount(right < 0);
             // for explanation, see 'doII'
-            return left >> (right >= 128 ? 127 : right);
+            return left >> (right >= 64 ? 63 : right);
         }
 
         @Specialization