rlc and rlca instructions

jonathanballs · Sep 12, 2024 · 2c73c1b · 2c73c1b
1 parent 798d860
commit 2c73c1b
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Showing 3 changed files with 31 additions and 11 deletions.
diff --git a/src/cpu/execution/bit.rs b/src/cpu/execution/bit.rs
@@ -54,6 +54,21 @@ impl CPU {
         self.registers.f.zero = false;
     }
 
+    pub(in crate::cpu) fn rlc(&mut self, mmu: &mut MMU, r: R8) {
+        let value = self.get_r8_byte(mmu, r);
+        let result = (value << 1) | (value >> 7);
+        self.set_r8_byte(mmu, r, result);
+        self.registers.f.zero = result == 0;
+        self.registers.f.subtract = false;
+        self.registers.f.half_carry = false;
+        self.registers.f.carry = value >> 7 == 1;
+    }
+
+    pub(in crate::cpu) fn rlca(&mut self, mmu: &mut MMU) {
+        self.rlc(mmu, R8::A);
+        self.registers.f.zero = false;
+    }
+
     pub(in crate::cpu) fn srl(&mut self, mmu: &mut MMU, reg: R8) {
         let value = self.get_r8_byte(mmu, reg);
         let result = value >> 1;
@@ -75,13 +90,15 @@ impl CPU {
         self.registers.f.zero = new_value == 0;
     }
 
-    pub(in crate::cpu) fn rlca(&mut self) {
-        let value = self.registers.a;
-        self.registers.f.carry = value & 0x80 == 0x80;
-        self.registers.f.zero = false;
+    pub(in crate::cpu) fn sra(&mut self, mmu: &mut MMU, reg: R8) {
+        let value = self.get_r8_byte(mmu, reg);
+        let result = value >> 1;
+        self.set_r8_byte(mmu, reg, result);
+
+        self.registers.f.carry = value & 0x1 == 0x1;
         self.registers.f.half_carry = false;
         self.registers.f.subtract = false;
-        self.registers.a = (value << 1) | (value >> 7);
+        self.registers.f.zero = result == 0;
     }
 
     pub(in crate::cpu) fn cpl(&mut self) {

diff --git a/src/cpu/execution/control_flow.rs b/src/cpu/execution/control_flow.rs
@@ -77,12 +77,12 @@ impl CPU {
      */
     pub(in crate::cpu) fn push(&mut self, mmu: &mut MMU, value: u16) {
         self.set_memory_word(mmu, self.registers.sp - 2, value);
-        self.registers.sp -= 2;
+        self.registers.sp = self.registers.sp.wrapping_sub(2);
     }
 
     pub(in crate::cpu) fn pop(&mut self, mmu: &mut MMU, reg: R16stk) {
         let value = self.get_memory_word(mmu, self.registers.sp);
         self.registers.set_r16_stk(reg, value);
-        self.registers.sp += 2;
+        self.registers.sp = self.registers.sp.wrapping_add(2);
     }
 }
diff --git a/src/cpu/mod.rs b/src/cpu/mod.rs
@@ -46,6 +46,7 @@ impl CPU {
             Instruction::LdhACmem => self.lda(mmu.read_byte(0xFF00 + self.registers.c as u16)),
             Instruction::LdHlSpImm8(n) => self.ld_hl_sp(n),
             Instruction::LdSpHl => self.ld_r16(R16::SP, self.registers.get_r16(R16::HL)),
+            Instruction::LdImm16memSp(n) => self.set_memory_word(mmu, self.registers.sp, n),
 
             // Arithmetic
             Instruction::IncR8(reg) => self.inc(mmu, reg),
@@ -81,8 +82,10 @@ impl CPU {
             Instruction::Rla => self.rla(mmu),
             Instruction::SrlR8(reg) => self.srl(mmu, reg),
             Instruction::SlaR8(reg) => self.sla(mmu, reg),
+            Instruction::SraR8(reg) => self.sra(mmu, reg),
             Instruction::Cpl => self.cpl(),
-            Instruction::Rlca => self.rlca(),
+            Instruction::RlcR8(r) => self.rlc(mmu, r),
+            Instruction::Rlca => self.rlca(mmu),
             Instruction::Daa => self.daa(),
             Instruction::SwapR8(reg) => self.swap(mmu, reg),
             Instruction::Scf => self.scf(),
@@ -216,11 +219,11 @@ impl CPU {
         }
     }
 
-    pub fn set_memory_word(&mut self, memory: &mut MMU, addr: u16, word: u16) {
+    pub fn set_memory_word(&mut self, mmu: &mut MMU, addr: u16, word: u16) {
         let little = (word & 0xFF) as u8;
         let big = (word >> 8) as u8;
-        memory.write_byte(addr, little);
-        memory.write_byte(addr + 1, big)
+        mmu.write_byte(addr, little);
+        mmu.write_byte(addr + 1, big)
     }
 
     pub fn get_memory_word(&mut self, memory: &MMU, addr: u16) -> u16 {