template TST TSTB

davecheney · Sep 22, 2020 · e7fc08a · e7fc08a
1 parent 3edcb5d
commit e7fc08a
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Showing 2 changed files with 20 additions and 22 deletions.
diff --git a/kb11.cc b/kb11.cc
@@ -440,26 +440,6 @@ void KB11::MOVB(const uint16_t instr) {
     setNZ<1>(src);
 }
 
-// TST 0057DD
-void KB11::TST(const uint16_t instr) {
-    auto dst = memread<2>(DA(instr));
-    PSW &= 0xFFF0;
-    setZ(dst == 0);
-    if (dst & 0x8000) {
-        PSW |= FLAGN;
-    }
-}
-
-// TSTB 1057DD
-void KB11::TSTB(const uint16_t instr) {
-    auto dst = memread<1>(DA(instr));
-    PSW &= 0xFFF0;
-    setZ(dst == 0);
-    if (dst & 0x80) {
-        PSW |= FLAGN;
-    }
-}
-
 // SWAB 0003DD
 void KB11::SWAB(const uint16_t instr) {
     auto da = DA(instr);
@@ -611,7 +591,7 @@ void KB11::step() {
                 SBC<2>(instr);
                 return;
             case 057: // TST 0057DD
-                TST(instr);
+                TST<2>(instr);
                 return;
             case 060: // ROR 0060DD
                 ROR<2>(instr);
@@ -759,7 +739,7 @@ void KB11::step() {
                 SBC<1>(instr);
                 return;
             case 057: // TSTB 1057DD
-                TSTB(instr);
+                TST<1>(instr);
                 return;
             case 060: // RORB 1060DD
                 ROR<1>(instr);

diff --git a/kb11.h b/kb11.h
@@ -185,6 +185,18 @@ class KB11 {
         }
     }
 
+    // Set N, Z,  clearing C & V
+    template <uint16_t len> void setNZC(uint16_t v) {
+        static_assert(len == 1 || len == 2);
+        PSW &= 0xFFF0;
+        if (v == 0) {
+            PSW |= FLAGZ;
+        }
+        if (v & (len == 2 ? 0x8000 : 0x80)) {
+            PSW |= FLAGN;
+        }
+    }
+
     template <uint8_t l> void BIC(const uint16_t instr) {
         const uint16_t msb = l == 2 ? 0x8000 : 0x80;
         const uint16_t max = l == 2 ? 0xFFFF : 0xff;
@@ -433,6 +445,12 @@ class KB11 {
         setNZ<l>(result);
     }
 
+    // TST 0057DD, TSTB 1057DD
+    template <uint16_t l> void TST(const uint16_t instr) {
+        auto dst = memread<l>(DA(instr));
+        setNZC<l>(dst);
+    }
+
     void ADD(const uint16_t instr);
     void SUB(const uint16_t instr);
     void JSR(const uint16_t instr);