[PATCH 134/203] Implement Rust field operations

Tom Tromey
2021-01-01T21:49:07Z

This implements the field operations STRUCTOP_STRUCT and
STRUCTOP_ANONYMOUS, for Rust.

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

* rust-lang.c (eval_op_rust_struct_anon, eval_op_rust_structop):
No longer static.
* rust-exp.h (class rust_struct_anon): New.
(class rust_structop): New.
---
gdb/ChangeLog | 7 +++++++
gdb/rust-exp.h | 53 +++++++++++++++++++++++++++++++++++++++++++++++++
gdb/rust-lang.c | 4 ++--
3 files changed, 62 insertions(+), 2 deletions(-)

diff --git a/gdb/rust-exp.h b/gdb/rust-exp.h
index 263d41a79d4..19e945c806b 100644
--- a/gdb/rust-exp.h
+++ b/gdb/rust-exp.h
@@ -46,6 +46,16 @@ extern struct value *rust_range (struct type *expect_type,
struct expression *exp,
enum noside noside, enum range_flag kind,
struct value *low, struct value *high);
+extern struct value *eval_op_rust_struct_anon (struct type *expect_type,
+ struct expression *exp,
+ enum noside noside,
+ int field_number,
+ struct value *lhs);
+extern struct value *eval_op_rust_structop (struct type *expect_type,
+ struct expression *exp,
+ enum noside noside,
+ struct value *lhs,
+ const char *field_name);

namespace expr
{
@@ -154,6 +164,49 @@ class rust_range_operation
{ return OP_RANGE; }
};

+/* Tuple field reference (using an integer). */
+class rust_struct_anon
+ : public tuple_holding_operation<int, operation_up>
+{
+public:
+
+ using tuple_holding_operation::tuple_holding_operation;
+
+ value *evaluate (struct type *expect_type,
+ struct expression *exp,
+ enum noside noside) override
+ {
+ value *lhs = std::get<1> (m_storage)->evaluate (nullptr, exp, noside);
+ return eval_op_rust_struct_anon (expect_type, exp, noside,
+ std::get<0> (m_storage), lhs);
+
+ }
+
+ enum exp_opcode opcode () const override
+ { return STRUCTOP_ANONYMOUS; }
+};
+
+/* Structure (or union or enum) field reference. */
+class rust_structop
+ : public structop_base_operation
+{
+public:
+
+ using structop_base_operation::structop_base_operation;
+
+ value *evaluate (struct type *expect_type,
+ struct expression *exp,
+ enum noside noside) override
+ {
+ value *lhs = std::get<0> (m_storage)->evaluate (nullptr, exp, noside);
+ return eval_op_rust_structop (expect_type, exp, noside, lhs,
+ std::get<1> (m_storage).c_str ());
+ }
+
+ enum exp_opcode opcode () const override
+ { return STRUCTOP_STRUCT; }
+};
+
} /* namespace expr */

#endif /* RUST_EXP_H */
diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c
index 68fbaf1642a..95b19776edf 100644
--- a/gdb/rust-lang.c
+++ b/gdb/rust-lang.c
@@ -1388,7 +1388,7 @@ eval_op_rust_array (struct type *expect_type, struct expression *exp,

/* A helper function for STRUCTOP_ANONYMOUS. */

-static struct value *
+struct value *
eval_op_rust_struct_anon (struct type *expect_type, struct expression *exp,
enum noside noside,
int field_number, struct value *lhs)
@@ -1455,7 +1455,7 @@ tuple structs, and tuple-like enum variants"));

/* A helper function for STRUCTOP_STRUCT. */

-static struct value *
+struct value *
eval_op_rust_structop (struct type *expect_type, struct expression *exp,
enum noside noside,
struct value *lhs, const char *field_name)
--
2.26.2