[PATCH 085/203] Introduce internalvar_operation

Tom Tromey
2021-01-01T21:48:29Z

This adds class internalvar_operation, which implements
OP_INTERNALVAR.

gdb/ChangeLog
2021-01-01 Tom Tromey <tom@tromey.com>

* expop.h (class internalvar_operation): New.
* ax-gdb.c (internalvar_operation::do_generate_ax): New method.
---
gdb/ChangeLog | 5 +++++
gdb/ax-gdb.c | 25 +++++++++++++++++++++++++
gdb/expop.h | 32 ++++++++++++++++++++++++++++++++
3 files changed, 62 insertions(+)

diff --git a/gdb/ax-gdb.c b/gdb/ax-gdb.c
index 5ffe5a00da1..e25e2942475 100644
--- a/gdb/ax-gdb.c
+++ b/gdb/ax-gdb.c
@@ -2365,6 +2365,31 @@ register_operation::do_generate_ax (struct expression *exp,
value->type = register_type (ax->gdbarch, reg);
}

+void
+internalvar_operation::do_generate_ax (struct expression *exp,
+ struct agent_expr *ax,
+ struct axs_value *value,
+ struct type *cast_type)
+{
+ struct internalvar *var = std::get<0> (m_storage);
+ const char *name = internalvar_name (var);
+ struct trace_state_variable *tsv;
+
+ tsv = find_trace_state_variable (name);
+ if (tsv)
+ {
+ ax_tsv (ax, aop_getv, tsv->number);
+ if (ax->tracing)
+ ax_tsv (ax, aop_tracev, tsv->number);
+ /* Trace state variables are always 64-bit integers. */
+ value->kind = axs_rvalue;
+ value->type = builtin_type (ax->gdbarch)->builtin_long_long;
+ }
+ else if (! compile_internalvar_to_ax (var, ax, value))
+ error (_("$%s is not a trace state variable; GDB agent "
+ "expressions cannot use convenience variables."), name);
+}
+
}

/* This handles the middle-to-right-side of code generation for binary
diff --git a/gdb/expop.h b/gdb/expop.h
index 2c2f76d1da1..989d54d90ad 100644
--- a/gdb/expop.h
+++ b/gdb/expop.h
@@ -638,6 +638,38 @@ class bool_operation
{ return true; }
};

+class internalvar_operation
+ : public tuple_holding_operation<internalvar *>
+{
+public:
+
+ using tuple_holding_operation::tuple_holding_operation;
+
+ value *evaluate (struct type *expect_type,
+ struct expression *exp,
+ enum noside noside) override
+ {
+ return value_of_internalvar (exp->gdbarch,
+ std::get<0> (m_storage));
+ }
+
+ internalvar *get_internalvar () const
+ {
+ return std::get<0> (m_storage);
+ }
+
+ enum exp_opcode opcode () const override
+ { return OP_INTERNALVAR; }
+
+protected:
+
+ void do_generate_ax (struct expression *exp,
+ struct agent_expr *ax,
+ struct axs_value *value,
+ struct type *cast_type)
+ override;
+};
+
} /* namespace expr */

#endif /* EXPOP_H */
--
2.26.2