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| author | Tom Tromey <tom@tromey.com> | 2022-03-25 13:36:53 -0600 |
|---|---|---|
| committer | Tom Tromey <tom@tromey.com> | 2022-04-15 10:34:03 -0600 |
| commit | 506ec52e8805d8edd538d6bd11750489a8c8bbee (patch) | |
| tree | 9201c10e67505609846c0a6f51ed98c033a3e3c6 /gdb/rust-lang.c | |
| parent | 925ea601f1892c6eb344e2c916f0ef448b42b606 (diff) | |
| download | gdb-506ec52e8805d8edd538d6bd11750489a8c8bbee.zip gdb-506ec52e8805d8edd538d6bd11750489a8c8bbee.tar.gz gdb-506ec52e8805d8edd538d6bd11750489a8c8bbee.tar.bz2 | |
Reimplement Rust slice printing
The current nightly Rust compiler (aka 1.61) added better DWARF
representation for unsized types. Fixing this is PR rust/21466; but
the code is actually the same as what is required to make slice
printing more useful, which is PR rust/23871. This patch implements
this. I tested this against various Rust compilers: 1.48, current
stable, current beta, and current nightly.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=21466
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23871
Diffstat (limited to 'gdb/rust-lang.c')
| -rw-r--r-- | gdb/rust-lang.c | 85 |
1 files changed, 59 insertions, 26 deletions
diff --git a/gdb/rust-lang.c b/gdb/rust-lang.c index fdd6e3f..d4a221a 100644 --- a/gdb/rust-lang.c +++ b/gdb/rust-lang.c @@ -159,10 +159,19 @@ rust_tuple_struct_type_p (struct type *type) static bool rust_slice_type_p (struct type *type) { - return (type->code () == TYPE_CODE_STRUCT - && type->name () != NULL - && (strncmp (type->name (), "&[", 2) == 0 - || strcmp (type->name (), "&str") == 0)); + if (type->code () == TYPE_CODE_STRUCT + && type->name () != NULL + && type->num_fields () == 2) + { + /* The order of fields doesn't matter. While it would be nice + to check for artificiality here, the Rust compiler doesn't + emit this information. */ + const char *n1 = type->field (0).name (); + const char *n2 = type->field (1).name (); + return ((streq (n1, "data_ptr") && streq (n2, "length")) + || (streq (n2, "data_ptr") && streq (n1, "length"))); + } + return false; } /* Return true if TYPE is a range type, otherwise false. */ @@ -296,19 +305,57 @@ rust_language::printstr (struct ui_file *stream, struct type *type, -/* Helper function to print a string slice. */ +static const struct generic_val_print_decorations rust_decorations = +{ + /* Complex isn't used in Rust, but we provide C-ish values just in + case. */ + "", + " + ", + " * I", + "true", + "false", + "()", + "[", + "]" +}; + +/* Helper function to print a slice. */ static void -rust_val_print_str (struct ui_file *stream, struct value *val, - const struct value_print_options *options) +rust_val_print_slice (struct value *val, struct ui_file *stream, int recurse, + const struct value_print_options *options) { struct value *base = value_struct_elt (&val, {}, "data_ptr", NULL, "slice"); struct value *len = value_struct_elt (&val, {}, "length", NULL, "slice"); - val_print_string (TYPE_TARGET_TYPE (value_type (base)), "UTF-8", - value_as_address (base), value_as_long (len), stream, - options); + struct type *type = check_typedef (value_type (val)); + if (strcmp (type->name (), "&str") == 0) + val_print_string (TYPE_TARGET_TYPE (value_type (base)), "UTF-8", + value_as_address (base), value_as_long (len), stream, + options); + else + { + LONGEST llen = value_as_long (len); + + type_print (value_type (val), "", stream, -1); + gdb_printf (stream, " "); + + if (llen == 0) + gdb_printf (stream, "[]"); + else + { + struct type *elt_type = TYPE_TARGET_TYPE (value_type (base)); + struct type *array_type = lookup_array_range_type (elt_type, 0, + llen - 1); + struct value *array = allocate_value_lazy (array_type); + VALUE_LVAL (array) = lval_memory; + set_value_address (array, value_as_address (base)); + value_fetch_lazy (array); + generic_value_print (array, stream, recurse, options, + &rust_decorations); + } + } } /* See rust-lang.h. */ @@ -322,9 +369,9 @@ rust_language::val_print_struct int first_field; struct type *type = check_typedef (value_type (val)); - if (rust_slice_type_p (type) && strcmp (type->name (), "&str") == 0) + if (rust_slice_type_p (type)) { - rust_val_print_str (stream, val, options); + rust_val_print_slice (val, stream, recurse, options); return; } @@ -468,20 +515,6 @@ rust_language::print_enum (struct value *val, struct ui_file *stream, gdb_puts ("}", stream); } -static const struct generic_val_print_decorations rust_decorations = -{ - /* Complex isn't used in Rust, but we provide C-ish values just in - case. */ - "", - " + ", - " * I", - "true", - "false", - "()", - "[", - "]" -}; - /* See language.h. */ void |