Impl Thumb LdrStrImmOffset

Former-commit-id: 17d6f4ae1cb5f68b9fccf35536a6346e88326e77

src/arm7tdmi/thumb/display.rs

@@ -86,13 +86,40 @@ impl ThumbInstruction {
             f,
             "{op}{b}\t{Rd}, [{Rb}, {Ro}]",
             op = if self.is_load() { "ldr" } else { "str" },
-            b = if self.is_transfering_bytes() { "b" } else { "" },
+            b = if self.is_transferring_bytes() {
+                "b"
+            } else {
+                ""
+            },
             Rd = reg_string(self.rd()),
             Rb = reg_string(self.rb()),
             Ro = reg_string(self.ro()),
         )
     }
 
+    fn fmt_thumb_ldr_str_imm_offset(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(
+            f,
+            "{op}{b}\t{Rd}, [{Rb}, #{imm:#x}]",
+            op = if self.is_load() { "ldr" } else { "str" },
+            b = if self.is_transferring_bytes() {
+                "b"
+            } else {
+                ""
+            },
+            Rd = reg_string(self.rd()),
+            Rb = reg_string(self.rb()),
+            imm = {
+                let offset5 = self.offset5();
+                if self.is_transferring_bytes() {
+                    offset5
+                } else {
+                    (offset5 << 3) >> 1
+                }
+            },
+        )
+    }
+
     fn fmt_thumb_ldr_str_halfword(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(
             f,
@@ -204,6 +231,7 @@ impl fmt::Display for ThumbInstruction {
             ThumbFormat::HiRegOpOrBranchExchange => self.fmt_thumb_high_reg_op_or_bx(f),
             ThumbFormat::LdrPc => self.fmt_thumb_ldr_pc(f),
             ThumbFormat::LdrStrRegOffset => self.fmt_thumb_ldr_str_reg_offset(f),
+            ThumbFormat::LdrStrImmOffset => self.fmt_thumb_ldr_str_imm_offset(f),
             ThumbFormat::LdrStrHalfWord => self.fmt_thumb_ldr_str_halfword(f),
             ThumbFormat::LdrStrSp => self.fmt_thumb_ldr_str_sp(f),
             ThumbFormat::AddSp => self.fmt_thumb_add_sp(f),

src/arm7tdmi/thumb/exec.rs

@@ -153,16 +153,14 @@ impl Core {
         Ok(CpuPipelineAction::IncPC)
     }
 
-    fn exec_thumb_ldr_str_reg_offset(
+    fn do_exec_thumb_ldr_str(
         &mut self,
         bus: &mut Bus,
         insn: ThumbInstruction,
+        addr: Addr,
     ) -> CpuExecResult {
-        let addr = self
-            .get_reg(insn.rb())
-            .wrapping_add(self.get_reg(insn.ro()));
         if insn.is_load() {
-            let data = if insn.is_transfering_bytes() {
+            let data = if insn.is_transferring_bytes() {
                 self.load_8(addr, bus) as u32
             } else {
                 self.load_32(addr, bus)
@@ -174,7 +172,7 @@ impl Core {
             self.add_cycle();
         } else {
             let value = self.get_reg(insn.rd());
-            if insn.is_transfering_bytes() {
+            if insn.is_transferring_bytes() {
                 self.store_8(addr, value as u8, bus);
             } else {
                 self.store_32(addr, value, bus);
@@ -184,6 +182,31 @@ impl Core {
         Ok(CpuPipelineAction::IncPC)
     }
 
+    fn exec_thumb_ldr_str_reg_offset(
+        &mut self,
+        bus: &mut Bus,
+        insn: ThumbInstruction,
+    ) -> CpuExecResult {
+        let addr = self
+            .get_reg(insn.rb())
+            .wrapping_add(self.get_reg(insn.ro()));
+        self.do_exec_thumb_ldr_str(bus, insn, addr)
+    }
+
+    fn exec_thumb_ldr_str_imm_offset(
+        &mut self,
+        bus: &mut Bus,
+        insn: ThumbInstruction,
+    ) -> CpuExecResult {
+        let offset = if insn.is_transferring_bytes() {
+            insn.offset5()
+        } else {
+            (insn.offset5() << 3) >> 1
+        };
+        let addr = self.get_reg(insn.rb()).wrapping_add(offset as u32);
+        self.do_exec_thumb_ldr_str(bus, insn, addr)
+    }
+
     fn exec_thumb_ldr_str_halfword(
         &mut self,
         bus: &mut Bus,
@@ -306,6 +329,7 @@ impl Core {
             ThumbFormat::HiRegOpOrBranchExchange => self.exec_thumb_hi_reg_op_or_bx(bus, insn),
             ThumbFormat::LdrPc => self.exec_thumb_ldr_pc(bus, insn),
             ThumbFormat::LdrStrRegOffset => self.exec_thumb_ldr_str_reg_offset(bus, insn),
+            ThumbFormat::LdrStrImmOffset => self.exec_thumb_ldr_str_imm_offset(bus, insn),
             ThumbFormat::LdrStrHalfWord => self.exec_thumb_ldr_str_halfword(bus, insn),
             ThumbFormat::LdrStrSp => self.exec_thumb_ldr_str_sp(bus, insn),
             ThumbFormat::AddSp => self.exec_thumb_add_sp(bus, insn),

src/arm7tdmi/thumb/mod.rs

@@ -261,7 +261,7 @@ impl ThumbInstruction {
         self.raw.bit_range(0..8) << 2
     }
 
-    pub fn is_transfering_bytes(&self) -> bool {
+    pub fn is_transferring_bytes(&self) -> bool {
         self.raw.bit(10)
     }