Fixed st8 on arm/risc evals

3 files changed, 30 insertions, 2 deletions

diff --git a/chapter21/src/test/java/com/seaofnodes/simple/Chapter21Test.java b/chapter21/src/test/java/com/seaofnodes/simple/Chapter21Test.java
index d8a5cebc..a5d86fa5 100644
--- a/chapter21/src/test/java/com/seaofnodes/simple/Chapter21Test.java
+++ b/chapter21/src/test/java/com/seaofnodes/simple/Chapter21Test.java
@@ -11,6 +11,34 @@ import org.junit.Test;
 import static org.junit.Assert.*;
 
 public class Chapter21Test {
+    @Test public void testRisc64BitStore() {
+        byte[] mem = new byte[24];
+        EvalRisc5 cpu = new EvalRisc5(mem,mem.length);
+        check64BitStore(mem,cpu::st8,cpu::ld8);
+    }
+
+    @Test public void testArm64BitStore() {
+        byte[] mem = new byte[24];
+        EvalArm64 cpu = new EvalArm64(mem,mem.length);
+        check64BitStore(mem,cpu::st8,cpu::ld8);
+    }
+
+    // Check bytes independently of ld8, including overwrite and adjacent memory.
+    private static void check64BitStore(byte[] mem,
+                                       java.util.function.BiConsumer<Integer,Long> store,
+                                       java.util.function.IntToLongFunction load) {
+        java.util.Arrays.fill(mem,(byte)0xA5);
+        for( long value : new long[]{0x0123456789ABCDEFL,0xFEDCBA9876543210L,
+                                     -1L,0L,Long.MIN_VALUE,Long.MAX_VALUE} ) {
+            store.accept(8,value);
+            for( int i=0; i<mem.length; i++ ) {
+                int expected = i>=8 && i<16 ? (int)(value >>> (8*(i-8)))&0xFF : 0xA5;
+                assertEquals("byte "+i,expected,mem[i]&0xFF);
+            }
+            assertEquals(value,load.applyAsLong(8));
+        }
+    }
+
 
     @Test @Ignore
     public void testJig() throws IOException {
diff --git a/chapter21/src/test/java/com/seaofnodes/simple/EvalArm64.java b/chapter21/src/test/java/com/seaofnodes/simple/EvalArm64.java
index 3ea9bea0..c10eccde 100644
--- a/chapter21/src/test/java/com/seaofnodes/simple/EvalArm64.java
+++ b/chapter21/src/test/java/com/seaofnodes/simple/EvalArm64.java
@@ -50,7 +50,7 @@ public class EvalArm64 {
     public void st1(int x, int  val) { _buf[x] = (byte)val; }
     public void st2(int x, int  val) { st1(x,val); st1(x+1,val>> 8); }
     public void st4(int x, int  val) { st2(x,val); st2(x+2,val>>16); }
-    public void st8(int x, long val) { st4(x,(int)val); st2(x+4,(int)(val>>32)); }
+    public void st8(int x, long val) { st4(x,(int)val); st4(x+4,(int)(val>>32)); }
 
     public int step(int maxops) {
         int trap = 0;
diff --git a/chapter21/src/test/java/com/seaofnodes/simple/EvalRisc5.java b/chapter21/src/test/java/com/seaofnodes/simple/EvalRisc5.java
index fd953342..aa9702f1 100644
--- a/chapter21/src/test/java/com/seaofnodes/simple/EvalRisc5.java
+++ b/chapter21/src/test/java/com/seaofnodes/simple/EvalRisc5.java
@@ -55,7 +55,7 @@ import java.util.Arrays;
     public void st1(int x, int  val) { _buf[x] = (byte)val; }
     public void st2(int x, int  val) { st1(x,val); st1(x+1,val>> 8); }
     public void st4(int x, int  val) {st2(x,val); st2(x+2,val>>16); }
-    public void st8(int x, long val) { st4(x,(int)val); st2(x+4,(int)(val>>32)); }
+    public void st8(int x, long val) { st4(x,(int)val); st4(x+4,(int)(val>>32)); }
 
     // Note: only a few bits are used.  (Machine = 3, User = 0)
     // Bits 0..1 = privilege.