port div32

src/browser/starter.js

@@ -195,7 +195,6 @@ function V86Starter(options)
         "_load_tr": function() { return cpu.load_tr.apply(cpu, arguments); },
 
         "_idiv16": function() { return cpu.idiv16.apply(cpu, arguments); },
-        "_div32": function() { return cpu.div32.apply(cpu, arguments); },
         "_idiv32": function() { return cpu.idiv32.apply(cpu, arguments); },
         "_insb": function() { return cpu.insb.apply(cpu, arguments); },
         "_insw": function() { return cpu.insw.apply(cpu, arguments); },

src/cpu.js

@@ -278,6 +278,7 @@ CPU.prototype.wasm_patch = function(wm)
     this.raise_exception_with_code = this.wm.funcs['_raise_exception_with_code'];
     this.trigger_de = this.wm.funcs['_trigger_de'];
     this.trigger_gp = this.wm.funcs['_trigger_gp'];
+    this.div32 = this.wm.funcs['_div32'];
 
     this.shl8 = this.wm.funcs['_shl8'];
     this.shl16 = this.wm.funcs['_shl16'];

src/native/arith.c

@@ -815,6 +815,31 @@ void div16(uint32_t source_operand)
     }
 }
 
+void div32(uint32_t source_operand)
+{
+    if(source_operand == 0)
+    {
+        trigger_de();
+        return;
+    }
+
+    uint32_t target_low = reg32s[EAX];
+    uint32_t target_high = reg32s[EDX];
+
+    uint64_t target_operand = (((uint64_t) target_high) << 32) | ((uint64_t) target_low);
+    uint64_t result = target_operand / source_operand;
+    if(result > UINT32_MAX)
+    {
+        trigger_de();
+        return;
+    }
+
+    int32_t mod = target_operand % source_operand;
+
+    reg32s[EAX] = result;
+    reg32s[EDX] = mod;
+}
+
 int32_t shl8(int32_t dest_operand, int32_t count)
 {
     if(count == 0)

src/native/instructions.c

@@ -183,7 +183,7 @@ int32_t rcr32(int32_t, int32_t);
 int32_t rcl32(int32_t, int32_t);
 
 int32_t idiv16(int32_t);
-int32_t div32(int32_t);
+void div32(uint32_t);
 int32_t idiv32(int32_t);