Ensure opcodes with FD and FF prefix are executed atomically

.vscode/launch.json

@@ -7,16 +7,16 @@
         {
             "type": "lldb",
             "request": "launch",
-            "name": "Debug unit tests in library 'z80'",
+            "name": "Debug unit tests in library 'iz80'",
             "cargo": {
                 "args": [
                     "test",
                     "--no-run",
                     "--lib",
-                    "--package=z80"
+                    "--package=iz80"
                 ],
                 "filter": {
-                    "name": "z80",
+                    "name": "iz80",
                     "kind": "lib"
                 }
             },
@@ -26,15 +26,15 @@
         {
             "type": "lldb",
             "request": "launch",
-            "name": "Debug executable 'z80'",
+            "name": "Debug executable 'iz80'",
             "cargo": {
                 "args": [
                     "build",
-                    "--bin=z80",
-                    "--package=z80"
+                    "--bin=iz80",
+                    "--package=iz80"
                 ],
                 "filter": {
-                    "name": "z80",
+                    "name": "iz80",
                     "kind": "bin"
                 }
             },
@@ -44,16 +44,16 @@
         {
             "type": "lldb",
             "request": "launch",
-            "name": "Debug unit tests in executable 'z80'",
+            "name": "Debug unit tests in executable 'iz80'",
             "cargo": {
                 "args": [
                     "test",
                     "--no-run",
-                    "--bin=z80",
-                    "--package=z80"
+                    "--bin=iz80",
+                    "--package=iz80"
                 ],
                 "filter": {
-                    "name": "z80",
+                    "name": "iz80",
                     "kind": "bin"
                 }
             },
@@ -69,7 +69,7 @@
                     "test",
                     "--no-run",
                     "--test=opcodes_arith",
-                    "--package=z80"
+                    "--package=iz80"
                 ],
                 "filter": {
                     "name": "opcodes_arith",
@@ -88,7 +88,7 @@
                     "test",
                     "--no-run",
                     "--test=opcodes_bits",
-                    "--package=z80"
+                    "--package=iz80"
                 ],
                 "filter": {
                     "name": "opcodes_bits",
@@ -107,7 +107,7 @@
                     "test",
                     "--no-run",
                     "--test=opcodes_jumps",
-                    "--package=z80"
+                    "--packagei=z80"
                 ],
                 "filter": {
                     "name": "opcodes_jumps",
@@ -126,7 +126,7 @@
                     "test",
                     "--no-run",
                     "--test=opcodes_io",
-                    "--package=z80"
+                    "--package=iz80"
                 ],
                 "filter": {
                     "name": "opcodes_io",
@@ -145,7 +145,7 @@
                     "test",
                     "--no-run",
                     "--test=opcodes_ld",
-                    "--package=z80"
+                    "--package=iz80"
                 ],
                 "filter": {
                     "name": "opcodes_ld",
@@ -164,7 +164,7 @@
                     "test",
                     "--no-run",
                     "--test=opcodes",
-                    "--package=z80"
+                    "--package=iz80"
                 ],
                 "filter": {
                     "name": "opcodes",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "iz80"
-version = "0.3.4"
+version = "0.3.5"
 authors = ["Ivan Izaguirre <[email protected]>"]
 edition = "2018"
 license = "BSD-3-Clause"

README.md

@@ -199,3 +199,13 @@ sta nnnn / lda nnnn...........  OK
 stax <b,d>....................  OK
 Tests complete
 ```
+
+### Pre-commit tests
+
+Note that some of the Zexall tests takes very long and is disabled for continuouos integrations. To run it, execute:
+
+```
+cargo test --release -- --nocapture --ignored --test zexall
+
+```
+

publishing.txt

@@ -1,4 +1,4 @@
 Reminder:
 - Change the version in Cargo.toml, rebuild and commit
 - Create a tag (git tag v0.3.4) and push (git push --tags)
-- Publish (cargo Publish)
+- Publish (cargo publish)

src/cpu.rs

@@ -74,14 +74,13 @@ impl Cpu {
             env.subroutine_call(NMI_ADDRESS);
         }
 
-
         let pc = env.state.reg.pc();
         let opcode = self.decoder.decode(&mut env);
         if self.trace {
             print!("==> {:04x}: {:20}", pc, opcode.disasm(&mut env));
         }
         opcode.execute(&mut env);
-        env.step();
+        env.clear_index();
 
         if self.trace {
             print!(" PC:{:04x} AF:{:04x} BC:{:04x} DE:{:04x} HL:{:04x} SP:{:04x} IX:{:04x} IY:{:04x} Flags:{:08b}",

src/decoder_z80.rs

@@ -25,7 +25,21 @@ pub struct DecoderZ80 {
 
 impl Decoder for DecoderZ80 {
     fn decode(&self, env: &mut Environment) -> &Opcode {
-        let b0 = env.advance_pc();
+        let mut b0 = env.advance_pc();
+
+        // Process prefixes even if reapeated
+        while b0 == 0xdd || b0 == 0xfd {
+            if b0 == 0xdd {
+                // DD prefix
+                env.set_index(Reg16::IX);
+                b0 = env.advance_pc()
+            } else {
+                // FD prefix
+                env.set_index(Reg16::IY);
+                b0 = env.advance_pc()
+            }
+        }
+
         let opcode = match b0 {
             0xcb => {
                 if env.is_alt_index() {
@@ -222,9 +236,9 @@ impl DecoderZ80 {
                         0 => Some(build_push_rr(RP2[p.p])), // PUSH rr
                         1 => match p.p {
                             0 => Some(build_call()), // Call nn
-                            1 => Some(build_prefix(Reg16::IX)), // DD prefix
+                            1 => None, // DD prefix
                             2 => None, // ED prefix
-                            3 => Some(build_prefix(Reg16::IY)), // FD prefix
+                            3 => None, // FD prefix
                             _ => panic!("Unreachable")
                         },
                         _ => panic!("Unreachable")

src/environment.rs

@@ -78,21 +78,11 @@ impl <'a> Environment<'_> {
 
     pub fn set_index(&mut self, index: Reg16) {
         self.state.index = index;
-        self.state.index_changed = true;
-    }
-
-    pub fn step(&mut self) {
-        if self.state.index_changed {
-            self.state.index_changed = false;
-        } else {
-            self.clear_index();
-        }
     }
 
     pub fn clear_index(&mut self) {
         self.state.index = Reg16::HL;
         self.state.displacement_loaded = false;
-        self.state.index_changed = false;
     }
 
     pub fn index_description(&self) -> String {

src/opcode.rs

@@ -39,17 +39,6 @@ impl Opcode {
     }
 }
 
-pub fn build_prefix(index: Reg16) -> Opcode {
-    Opcode {
-        name: format!("PREFIX {:?}", index),
-        action: Box::new(move |env: &mut Environment| {
-            // Change the index mode to IX or IY
-            //let d = env.advance_pc() as i8;
-            env.set_index(index /*, d*/);
-        })
-    }
-}
-
 pub fn build_nop() -> Opcode {
     Opcode {
         name: "NOP".to_string(),

src/state.rs

@@ -15,7 +15,6 @@ pub struct State {
     pub index: Reg16, // Using HL, IX or IY
     pub displacement: i8, // Used for (IX+d) and (iY+d)
     pub displacement_loaded: bool, // TODO: remove
-    pub index_changed: bool, // Use the index change for the next opcode, reset afterwards
 }
 
 impl State {
@@ -28,7 +27,6 @@ impl State {
             index: Reg16::HL,
             displacement: 0,
             displacement_loaded: false,
-            index_changed: false
         }
     }
 }