[PATCH 050/203] Split out eval_op_rust_structop

Tom Tromey
2021-01-01T21:48:02Z

This splits STRUCTOP_STRUCT into a new function for future use.

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

* rust-lang.c (eval_op_rust_structop): New function.
(rust_evaluate_subexp): Use it.
---
gdb/ChangeLog | 5 +++
gdb/rust-lang.c | 90 ++++++++++++++++++++++++++++---------------------
2 files changed, 56 insertions(+), 39 deletions(-)

diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c
index a01e869a201..a7c62610a1d 100644
--- a/gdb/rust-lang.c
+++ b/gdb/rust-lang.c
@@ -1449,6 +1449,55 @@ eval_op_rust_struct_anon (struct type *expect_type, struct expression *exp,
tuple structs, and tuple-like enum variants"));
}

+/* A helper function for STRUCTOP_STRUCT. */
+
+static struct value *
+eval_op_rust_structop (struct type *expect_type, struct expression *exp,
+ enum noside noside,
+ struct value *lhs, const char *field_name)
+{
+ struct value *result;
+ struct type *type = value_type (lhs);
+ if (type->code () == TYPE_CODE_STRUCT && rust_enum_p (type))
+ {
+ gdb::array_view<const gdb_byte> view (value_contents (lhs),
+ TYPE_LENGTH (type));
+ type = resolve_dynamic_type (type, view, value_address (lhs));
+
+ if (rust_empty_enum_p (type))
+ error (_("Cannot access field %s of empty enum %s"),
+ field_name, type->name ());
+
+ int fieldno = rust_enum_variant (type);
+ lhs = value_primitive_field (lhs, 0, fieldno, type);
+
+ struct type *outer_type = type;
+ type = value_type (lhs);
+ if (rust_tuple_type_p (type) || rust_tuple_struct_type_p (type))
+ error (_("Attempting to access named field %s of tuple "
+ "variant %s::%s, which has only anonymous fields"),
+ field_name, outer_type->name (),
+ rust_last_path_segment (type->name ()));
+
+ try
+ {
+ result = value_struct_elt (&lhs, NULL, field_name,
+ NULL, "structure");
+ }
+ catch (const gdb_exception_error &except)
+ {
+ error (_("Could not find field %s of struct variant %s::%s"),
+ field_name, outer_type->name (),
+ rust_last_path_segment (type->name ()));
+ }
+ }
+ else
+ result = value_struct_elt (&lhs, NULL, field_name, NULL, "structure");
+ if (noside == EVAL_AVOID_SIDE_EFFECTS)
+ result = value_zero (value_type (result), VALUE_LVAL (result));
+ return result;
+}
+
/* evaluate_exp implementation for Rust. */

static struct value *
@@ -1595,7 +1644,6 @@ rust_evaluate_subexp (struct type *expect_type, struct expression *exp,
case STRUCTOP_STRUCT:
{
struct value *lhs;
- struct type *type;
int tem, pc;

pc = (*pos)++;
@@ -1604,44 +1652,8 @@ rust_evaluate_subexp (struct type *expect_type, struct expression *exp,
lhs = evaluate_subexp (nullptr, exp, pos, noside);

const char *field_name = &exp->elts[pc + 2].string;
- type = value_type (lhs);
- if (type->code () == TYPE_CODE_STRUCT && rust_enum_p (type))
- {
- gdb::array_view<const gdb_byte> view (value_contents (lhs),
- TYPE_LENGTH (type));
- type = resolve_dynamic_type (type, view, value_address (lhs));
-
- if (rust_empty_enum_p (type))
- error (_("Cannot access field %s of empty enum %s"),
- field_name, type->name ());
-
- int fieldno = rust_enum_variant (type);
- lhs = value_primitive_field (lhs, 0, fieldno, type);
-
- struct type *outer_type = type;
- type = value_type (lhs);
- if (rust_tuple_type_p (type) || rust_tuple_struct_type_p (type))
- error (_("Attempting to access named field %s of tuple "
- "variant %s::%s, which has only anonymous fields"),
- field_name, outer_type->name (),
- rust_last_path_segment (type->name ()));
-
- try
- {
- result = value_struct_elt (&lhs, NULL, field_name,
- NULL, "structure");
- }
- catch (const gdb_exception_error &except)
- {
- error (_("Could not find field %s of struct variant %s::%s"),
- field_name, outer_type->name (),
- rust_last_path_segment (type->name ()));
- }
- }
- else
- result = value_struct_elt (&lhs, NULL, field_name, NULL, "structure");
- if (noside == EVAL_AVOID_SIDE_EFFECTS)
- result = value_zero (value_type (result), VALUE_LVAL (result));
+ return eval_op_rust_structop (expect_type, exp, noside, lhs,
+ field_name);
}
break;

--
2.26.2