实现指令编解码与反汇编，冻结 disasm 格式。

- Encode.h/Encode.cpp：encode/decode 往返 + disasm 一行文本 - 指令与映像.md 新增反汇编格式表（9 种形态 + 未知操作码） - Op.h STORE_* 注释对齐 disasm（rs, slot 寄存器在前）
2026-08-19 14:06:20 +08:00
parent 7c855b1618
commit eba48f852e
4 changed files with 149 additions and 3 deletions
@@ -0,0 +1,96 @@
+/**
+ * @file Encode.cpp
+ * @brief 指令编解码与反汇编
+ * @author 
+ * @date 2026-08-19
+ */
+
+#include "isa/Encode.h"
+
+#include <cstdio>
+
+namespace isa {
+
+Instr encode(Decoded d) {
+    return pack(d.op, d.rd, d.a, d.b);
+}
+
+Decoded decode(Instr w) {
+    Decoded d;
+    d.op = op(w);
+    d.rd = rd(w);
+    d.a = a(w);
+    d.b = b(w);
+    return d;
+}
+
+void disasm(Instr w, char* out, size_t cap) {
+    if (cap == 0) {
+        return;
+    }
+    out[0] = '\0';
+
+    const Op o = op(w);
+    const int idx = static_cast<int>(o);
+    if (idx < 0 || idx >= kOpCount) {
+        snprintf(out, cap, "??? 0x%08x", static_cast<unsigned>(w));
+        return;
+    }
+    const char* m = mnemonic(o);
+
+    switch (o) {
+        case Op::MOVE:
+        case Op::NOT:
+            snprintf(out, cap, "%s r%u, r%u", m,
+                     static_cast<unsigned>(rd(w)), static_cast<unsigned>(a(w)));
+            break;
+        case Op::AND:
+        case Op::OR:
+        case Op::ADD:
+        case Op::SUB:
+        case Op::MUL:
+        case Op::DIV:
+        case Op::CMP_EQ:
+        case Op::CMP_NE:
+        case Op::CMP_LT:
+        case Op::CMP_LE:
+        case Op::CMP_GT:
+        case Op::CMP_GE:
+            snprintf(out, cap, "%s r%u, r%u, r%u", m,
+                     static_cast<unsigned>(rd(w)), static_cast<unsigned>(a(w)),
+                     static_cast<unsigned>(b(w)));
+            break;
+        case Op::LOADK:
+            snprintf(out, cap, "%s r%u, %u", m,
+                     static_cast<unsigned>(rd(w)), static_cast<unsigned>(imm16(w)));
+            break;
+        case Op::JMP:
+            snprintf(out, cap, "%s %+d", m, static_cast<int>(off16(w)));
+            break;
+        case Op::JT:
+        case Op::JF:
+            snprintf(out, cap, "%s r%u, %+d", m,
+                     static_cast<unsigned>(rd(w)), static_cast<int>(off16(w)));
+            break;
+        case Op::LOAD_I:
+        case Op::STORE_Q:
+        case Op::LOAD_M:
+        case Op::STORE_M:
+        case Op::LOAD_GLOBAL:
+        case Op::STORE_GLOBAL:
+            snprintf(out, cap, "%s r%u, %u", m,
+                     static_cast<unsigned>(rd(w)), static_cast<unsigned>(imm16(w)));
+            break;
+        case Op::CAL_TON:
+        case Op::CAL_TOF:
+        case Op::CAL_CTU:
+        case Op::CALL:
+            snprintf(out, cap, "%s %u", m, static_cast<unsigned>(imm16(w)));
+            break;
+        case Op::RET:
+            snprintf(out, cap, "%s", m);
+            break;
+    }
+}
+
+}  // namespace isa