feat(debug): complete the interactive debugger with disassembly, breakpoints, watchpoints and execution control

Assisted-by: DeepSeek V4 Pro

debug/disasm_linux_amd64.go

@@ -0,0 +1,52 @@
+// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
+// SPDX-License-Identifier: BSD-3-Clause
+
+//go:build linux && amd64
+
+package debug
+
+import (
+	"fmt"
+
+	"golang.org/x/arch/x86/x86asm"
+)
+
+// Disassemble decodes the instruction at the given address in the debuggee's
+// memory and returns its text representation and length in bytes.
+func (s *Session) Disassemble(addr uint64) (string, int, error) {
+	// Read up to 15 bytes (max x86 instruction length).
+	mem, err := s.ReadMemory(addr, 15)
+	if err != nil {
+		// Try a shorter read if we're near a page boundary.
+		mem, err = s.ReadMemory(addr, 1)
+		if err != nil {
+			return "", 0, err
+		}
+	}
+	inst, err := x86asm.Decode(mem, 64)
+	if err != nil {
+		return "???", 1, nil
+	}
+	text := x86asm.IntelSyntax(inst, addr, nil)
+	return text, inst.Len, nil
+}
+
+// DisassembleN decodes up to n instructions starting at addr and returns
+// them as a formatted string with addresses and byte offsets.
+func (s *Session) DisassembleN(addr uint64, n int) string {
+	var result string
+	pc := addr
+	for i := 0; i < n; i++ {
+		text, length, err := s.Disassemble(pc)
+		if err != nil {
+			result += fmt.Sprintf("  %#08x: <error: %v>\n", pc, err)
+			break
+		}
+		result += fmt.Sprintf("  %#08x: %s\n", pc, text)
+		if length == 0 {
+			length = 1
+		}
+		pc += uint64(length)
+	}
+	return result
+}