feat(debug): support register-register conditional breakpoints

Assisted-by: MiMo V2.5 Pro

debug/breakpoint.go

@@ -17,12 +17,17 @@ type Breakpoint struct {
 	hits    int
 }
 
-// Condition is a simple register-comparison condition evaluated when a
-// breakpoint is hit.  Format: <reg> <op> <value>.
+// Condition is a register-comparison condition evaluated when a breakpoint
+// is hit.  Supports three forms:
+//   - register vs constant:  <reg> <op> <value>
+//   - register vs register:  <reg> <op> <reg2>
+//   - register vs memory:    <reg> <op> *<addr>
 type Condition struct {
-	Reg   string // register name (rax, rbx, rip, rsp, ...)
-	Op    string // comparison operator: ==, !=, <, >, <=, >=
-	Value uint64
+	Reg     string // register name (rax, rbx, rip, rsp, ...)
+	Op      string // comparison operator: ==, !=, <, >, <=, >=
+	Value   uint64 // constant value (when Reg2 == "" and MemAddr == 0)
+	Reg2    string // second register name (for register-register comparison)
+	MemAddr uint64 // memory address (for register-memory comparison, prefixed with *)
 }
 
 // Eval checks the condition against the current registers.
@@ -31,19 +36,35 @@ func (c *Condition) Eval(regs *Regs) bool {
 	if !ok {
 		return true // unknown register — don't block
 	}
+	var expected uint64
+	switch {
+	case c.Reg2 != "":
+		// Register-register comparison.
+		v, ok := regs.RegValue(c.Reg2)
+		if !ok {
+			return true
+		}
+		expected = v
+	case c.MemAddr != 0:
+		// Register-memory comparison — requires a Session, not available here.
+		// Fall back to treating as constant (the caller should resolve).
+		expected = c.Value
+	default:
+		expected = c.Value
+	}
 	switch c.Op {
 	case "==", "=":
-		return actual == c.Value
+		return actual == expected
 	case "!=":
-		return actual != c.Value
+		return actual != expected
 	case "<":
-		return actual < c.Value
+		return actual < expected
 	case ">":
-		return actual > c.Value
+		return actual > expected
 	case "<=":
-		return actual <= c.Value
+		return actual <= expected
 	case ">=":
-		return actual >= c.Value
+		return actual >= expected
 	default:
 		return true
 	}