Re: RFA: Changes to allow extensions to operator set

Andrew Cagney
2003-09-22T17:04:26Z

> Andrew,
>
> Here is a version of the patch I submitted earlier that I believe addresses
> your comments from last time. The specific changes from last time that you
> wanted were
>
> 1. Putting evaluate_exp into the exp_descriptor structure.
>
> 2. Modifying the description of the OP_EXTENDED_LAST operator slightly
> and including a note indicating the temporary nature of the extension
> mechanism and our intention to OOize expression handling in general.

Yes.

> Other parts you previously approved.

Are they in yet?

> If these changes were what you
> were after, I will commit.

Ok, once the others have been committed. Ada is now a little bit less
scary, Thanks!

Andrew

> ChangeLog:
>
> 2003-09-18 Paul N. Hilfinger <hilfingr@nile.gnat.com>
>
> * parser-defs.h (struct exp_descriptor): New definition, containing
> language-specific info for printing, prefixifying, dumping, and
> evaluating expressions.
> (exp_descriptor_standard): Declare new variable.
> (print_subexp): Make global and declare here (from expprint.c).
> (dump_subexp): Ditto.
> (dump_subexp_body_standard): Declare.
> (operator_length): Declare.
> (operator_length_standard): Declare.
> (op_name_standard): Declare.
> (print_subexp): Declare.
> (print_subexp_standard): Declare.
>
> * language.h (struct language_defn): Add la_exp_desc field to hold
> pointer to table for language-specific operators.
> Remove evaluate_exp field, which is now in struct exp_descriptor.
>
> * parse.c (length_of_subexp): Use operator_length to get
> operator lengths and arities for operators.
> Move most code to new operator_length_standard function.
> (operator_length_standard): New function taking most code from
> length_of_subexp.
> (prefixify_subexp): Remove large case and use operator_length instead.
> (operator_length): New function. Uses language-specific information.
> (exp_descriptor_standard): New constant.
> (parse_exp_1): Use renamings:
> dump_prefix_expression => dump_raw_expression and
> dump_postfix_expression => dump_prefix_expression.
>
> * expression.h (enum exp_opcode): Add definitions of OP_EXTENDED0
> and OP_EXTENDED_LAST.
> (dump_prefix_expression): Rename to ...
> (dump_raw_expression): New name.
> (dump_postfix_expression): Rename to ...
> (dump_prefix_expression): New name.
>
> * expprint.c (print_subexp): Make global, remove static declaration.
> Use language-specific print_subexp.
> Move most existing code to print_subexp_standard.
> (print_subexp_standard): New function, containing code formerly in
> print_subexp.
> (op_name): Add expression to argument signature.
> Use langauge-specific op_name.
> Move most code to op_name_standard.
> (op_name_standard): New function, containing code formerly in op_name.
> (dump_subexp): Make global. Add comment.
> Use new version of op_name function.
> Use language-specific dump_subexp_body, and move most existing code to
> dump_subexp_body_standard.
> (dump_subexp_body): New function.
> (dump_subexp_body_standard): New function, containing code formerly
> in dump_subexp.
> (dump_prefix_expression): Rename to dump_raw_expression.
> Remove attempt to print the expression via print_expression: it can't
> work before the expression is prefixified!
> Use new version of op_name.
> (dump_raw_expression): Renamed from dump_prefix_expression.
> (dump_postfix_expression): Rename to dump_prefix_expression, since
> that's what it does!
> Remove 'note' parameter, since this routine must be used on
> prefixified expression.
> (dump_prefix_expression): Renamed from dump_postfix_expression.
>
> * language.c (unknown_language): Add default la_exp_desc field and
> remove evaluate_exp field.
> (auto_language): Ditto.
> (local_language): Ditto.
> * f-lang.c (f_language_defn): Ditto.
> * c-lang.c (c_language_defn): Ditto.
> (cplus_language_defn): Ditto.
> (asm_language_defn): Ditto.
> (minimal_language_defn): Ditto.
> * p-lang.c (pascal_language_defn): Ditto.
> * m2-lang.c (m2_language_defn): Ditto.
> * objc-lang.c (objc_language_defn): Ditto.
>
> * jv-lang.c (exp_descriptor_java): New variable, containing
> Java-specific expression evaluator.
> (java_language_defn): Add la_exp_desc field.
> * scm-lang.c (exp_descriptor_scm): New variable, containing
> Scheme-specific expression evaluator.
> (scm_language_defn): Add la_exp_desc field.
> * objc-lang.c (print_object_command): Take evaluate_exp from the
> la_exp_desc field.
>
> * Makefile.in (eval.o): Add dependency on parser-defs.h.
>
> * eval.c: Include parser-defs.h for the full declaration of
> la_exp_desc's type.
> (evaluate_subexp): Get evaluate_exp out of la_exp_desc field.
>
>
>
> Index: current-public.25/gdb/p-lang.c
> --- current-public.25/gdb/p-lang.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/e/26_p-lang.c 1.1.1.2.2.1 644)
> +++ submit.16(w)/gdb/p-lang.c Tue, 16 Sep 2003 01:31:55 -0700 hilfingr (GdbPub/e/26_p-lang.c 1.1.1.2.2.3 644)
> @@ -451,9 +451,9 @@ const struct language_defn pascal_langua
> range_check_on,
> type_check_on,
> case_sensitive_on,
> + &exp_descriptor_standard,
> pascal_parse,
> pascal_error,
> - evaluate_subexp_standard,
> pascal_printchar, /* Print a character constant */
> pascal_printstr, /* Function to print string constant */
> pascal_emit_char, /* Print a single char */
> Index: current-public.25/gdb/Makefile.in
> --- current-public.25/gdb/Makefile.in Wed, 17 Sep 2003 23:22:28 -0700 hilfingr (GdbPub/g/6_Makefile.i 1.1.1.8.1.1.1.1.1.1.1.1.1.3.2.1 644)
> +++ submit.16(w)/gdb/Makefile.in Wed, 17 Sep 2003 23:35:15 -0700 hilfingr (GdbPub/g/6_Makefile.i 1.1.1.8.1.1.1.1.1.1.1.1.1.3.2.2 644)
> @@ -1735,7 +1735,8 @@ elfread.o: elfread.c $(defs_h) $(bfd_h)
> environ.o: environ.c $(defs_h) $(environ_h) $(gdb_string_h)
> eval.o: eval.c $(defs_h) $(gdb_string_h) $(symtab_h) $(gdbtypes_h) \
> $(value_h) $(expression_h) $(target_h) $(frame_h) $(language_h) \
> - $(f_lang_h) $(cp_abi_h) $(infcall_h) $(objc_lang_h) $(block_h)
> + $(f_lang_h) $(cp_abi_h) $(infcall_h) $(objc_lang_h) $(block_h) \
> + $(parser_defs_h)
> event-loop.o: event-loop.c $(defs_h) $(event_loop_h) $(event_top_h) \
> $(gdb_string_h)
> event-top.o: event-top.c $(defs_h) $(top_h) $(inferior_h) $(target_h) \
> Index: current-public.25/gdb/c-lang.c
> --- current-public.25/gdb/c-lang.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/g/28_c-lang.c 1.1.1.3.2.1 644)
> +++ submit.16(w)/gdb/c-lang.c Tue, 16 Sep 2003 21:35:59 -0700 hilfingr (GdbPub/g/28_c-lang.c 1.1.1.3.2.3 644)
> @@ -543,9 +543,9 @@ const struct language_defn c_language_de
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> c_preprocess_and_parse,
> c_error,
> - evaluate_subexp_standard,
> c_printchar, /* Print a character constant */
> c_printstr, /* Function to print string constant */
> c_emit_char, /* Print a single char */
> @@ -599,9 +599,9 @@ const struct language_defn cplus_languag
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> c_preprocess_and_parse,
> c_error,
> - evaluate_subexp_standard,
> c_printchar, /* Print a character constant */
> c_printstr, /* Function to print string constant */
> c_emit_char, /* Print a single char */
> @@ -632,9 +632,9 @@ const struct language_defn asm_language_
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> c_preprocess_and_parse,
> c_error,
> - evaluate_subexp_standard,
> c_printchar, /* Print a character constant */
> c_printstr, /* Function to print string constant */
> c_emit_char, /* Print a single char */
> @@ -670,9 +670,9 @@ const struct language_defn minimal_langu
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> c_preprocess_and_parse,
> c_error,
> - evaluate_subexp_standard,
> c_printchar, /* Print a character constant */
> c_printstr, /* Function to print string constant */
> c_emit_char, /* Print a single char */
> Index: current-public.25/gdb/eval.c
> --- current-public.25/gdb/eval.c Wed, 17 Sep 2003 23:22:28 -0700 hilfingr (GdbPub/h/26_eval.c 1.1.1.3.1.1.3.1 644)
> +++ submit.16(w)/gdb/eval.c Wed, 17 Sep 2003 23:37:29 -0700 hilfingr (GdbPub/h/26_eval.c 1.1.1.3.1.1.3.2 644)
> @@ -35,6 +35,7 @@
> #include "infcall.h"
> #include "objc-lang.h"
> #include "block.h"
> +#include "parser-defs.h"
>
> /* Defined in symtab.c */
> extern int hp_som_som_object_present;
> @@ -70,7 +71,8 @@ static struct value *
> evaluate_subexp (struct type *expect_type, struct expression *exp,
> int *pos, enum noside noside)
> {
> - return (*exp->language_defn->evaluate_exp) (expect_type, exp, pos, noside);
> + return (*exp->language_defn->la_exp_desc->evaluate_exp)
> + (expect_type, exp, pos, noside);
> }
> \f
> /* Parse the string EXP as a C expression, evaluate it,
> Index: current-public.25/gdb/expprint.c
> --- current-public.25/gdb/expprint.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/h/29_expprint.c 1.1.1.3.3.1 644)
> +++ submit.16(w)/gdb/expprint.c Thu, 18 Sep 2003 02:08:41 -0700 hilfingr (GdbPub/h/29_expprint.c 1.1.1.3.3.3 644)
> @@ -36,11 +36,6 @@
> #include <ctype.h>
> #endif
>
> -/* Prototypes for local functions */
> -
> -static void print_subexp (struct expression *, int *, struct ui_file *,
> - enum precedence);
> -
> void
> print_expression (struct expression *exp, struct ui_file *stream)
> {
> @@ -53,10 +48,19 @@ print_expression (struct expression *exp
> if the precedence of the main operator of this subexpression is less,
> parentheses are needed here. */
>
> -static void
> +void
> print_subexp (struct expression *exp, int *pos,
> struct ui_file *stream, enum precedence prec)
> {
> + exp->language_defn->la_exp_desc->print_subexp (exp, pos, stream, prec);
> +}
> +
> +/* Standard implementation of print_subexp for use in language_defn
> + vectors. */
> +void
> +print_subexp_standard (struct expression *exp, int *pos,
> + struct ui_file *stream, enum precedence prec)
> +{
> unsigned tem;
> const struct op_print *op_print_tab;
> int pc;
> @@ -547,10 +551,22 @@ op_string (enum exp_opcode op)
> /* Support for dumping the raw data from expressions in a human readable
> form. */
>
> -static char *op_name (int opcode);
> +static char *op_name (struct expression *, enum exp_opcode);
> +static int dump_subexp_body (struct expression *exp, struct ui_file *, int);
> +
> +/* Name for OPCODE, when it appears in expression EXP. */
>
> static char *
> -op_name (int opcode)
> +op_name (struct expression *exp, enum exp_opcode opcode)
> +{
> + return exp->language_defn->la_exp_desc->op_name (opcode);
> +}
> +
> +/* Default name for the standard operator OPCODE (i.e., one defined in
> + the definition of enum exp_opcode). */
> +
> +char *
> +op_name_standard (enum exp_opcode opcode)
> {
> switch (opcode)
> {
> @@ -737,8 +753,8 @@ op_name (int opcode)
> }
>
> void
> -dump_prefix_expression (struct expression *exp, struct ui_file *stream,
> - char *note)
> +dump_raw_expression (struct expression *exp, struct ui_file *stream,
> + char *note)
> {
> int elt;
> char *opcode_name;
> @@ -747,11 +763,6 @@ dump_prefix_expression (struct expressio
>
> fprintf_filtered (stream, "Dump of expression @ ");
> gdb_print_host_address (exp, stream);
> - fprintf_filtered (stream, ", %s:\nExpression: `", note);
> - if (exp->elts[0].opcode != OP_TYPE)
> - print_expression (exp, stream);
> - else
> - fprintf_filtered (stream, "Type printing not yet supported....");
> fprintf_filtered (stream, "'\n\tLanguage %s, %d elements, %ld bytes each.\n",
> exp->language_defn->la_name, exp->nelts,
> (long) sizeof (union exp_element));
> @@ -760,7 +771,7 @@ dump_prefix_expression (struct expressio
> for (elt = 0; elt < exp->nelts; elt++)
> {
> fprintf_filtered (stream, "\t%5d ", elt);
> - opcode_name = op_name (exp->elts[elt].opcode);
> + opcode_name = op_name (exp, exp->elts[elt].opcode);
>
> fprintf_filtered (stream, "%20s ", opcode_name);
> print_longest (stream, 'd', 0, exp->elts[elt].longconst);
> @@ -778,10 +789,11 @@ dump_prefix_expression (struct expressio
> }
> }
>
> -static int dump_subexp (struct expression *exp, struct ui_file *stream,
> - int elt);
> +/* Dump the subexpression of prefix expression EXP whose operator is at
> + position ELT onto STREAM. Returns the position of the next
> + subexpression in EXP. */
>
> -static int
> +int
> dump_subexp (struct expression *exp, struct ui_file *stream, int elt)
> {
> static int indent = 0;
> @@ -794,9 +806,34 @@ dump_subexp (struct expression *exp, str
> fprintf_filtered (stream, " ");
> indent += 2;
>
> - fprintf_filtered (stream, "%-20s ", op_name (exp->elts[elt].opcode));
> + fprintf_filtered (stream, "%-20s ", op_name (exp, exp->elts[elt].opcode));
> +
> + elt = dump_subexp_body (exp, stream, elt);
>
> - switch (exp->elts[elt++].opcode)
> + indent -= 2;
> +
> + return elt;
> +}
> +
> +/* Dump the operands of prefix expression EXP whose opcode is at
> + position ELT onto STREAM. Returns the position of the next
> + subexpression in EXP. */
> +
> +static int
> +dump_subexp_body (struct expression *exp, struct ui_file *stream, int elt)
> +{
> + return exp->language_defn->la_exp_desc->dump_subexp_body (exp, stream, elt);
> +}
> +
> +/* Default value for subexp_body in exp_descriptor vector. */
> +
> +int
> +dump_subexp_body_standard (struct expression *exp,
> + struct ui_file *stream, int elt)
> +{
> + int opcode = exp->elts[elt++].opcode;
> +
> + switch (opcode)
> {
> case TERNOP_COND:
> case TERNOP_SLICE:
> @@ -914,7 +951,7 @@ dump_subexp (struct expression *exp, str
> break;
> case OP_FUNCALL:
> {
> - int nargs;
> + int i, nargs;
>
> nargs = longest_to_int (exp->elts[elt].longconst);
>
> @@ -1006,20 +1043,17 @@ dump_subexp (struct expression *exp, str
> fprintf_filtered (stream, "Unknown format");
> }
>
> - indent -= 2;
> -
> return elt;
> }
>
> void
> -dump_postfix_expression (struct expression *exp, struct ui_file *stream,
> - char *note)
> +dump_prefix_expression (struct expression *exp, struct ui_file *stream)
> {
> int elt;
>
> fprintf_filtered (stream, "Dump of expression @ ");
> gdb_print_host_address (exp, stream);
> - fprintf_filtered (stream, ", %s:\nExpression: `", note);
> + fputs_filtered (", after conversion to prefix form:\nExpression: `", stream);
> if (exp->elts[0].opcode != OP_TYPE)
> print_expression (exp, stream);
> else
> Index: current-public.25/gdb/expression.h
> --- current-public.25/gdb/expression.h Tue, 17 Jun 2003 02:35:33 -0700 hilfingr (GdbPub/h/30_expression 1.1.1.2 644)
> +++ submit.16(w)/gdb/expression.h Thu, 18 Sep 2003 01:44:54 -0700 hilfingr (GdbPub/h/30_expression 1.1.1.6 644)
> @@ -322,7 +322,27 @@ enum exp_opcode
> OP_EXPRSTRING,
>
> /* An Objective C Foundation Class NSString constant */
> - OP_OBJC_NSSTRING
> + OP_OBJC_NSSTRING,
> +
> + /* First extension operator. Individual language modules define
> + extra operators they need as constants with values
> + OP_LANGUAGE_SPECIFIC0 + k, for k >= 0, using a separate
> + enumerated type definition:
> + enum foo_extension_operator {
> + BINOP_MOGRIFY = OP_EXTENDED0,
> + BINOP_FROB,
> + ...
> + }; */
> + OP_EXTENDED0,
> +
> + /* Last possible extension operator. Defined to provide an
> + explicit and finite number of extended operators. */
> + OP_EXTENDED_LAST = 0xff
> + /* NOTE: Eventually, we expect to convert to an object-oriented
> + formulation for expression operators that does away with the
> + need for these extension operators, and indeed for this
> + entire enumeration type. Therefore, consider the OP_EXTENDED
> + definitions to be a temporary measure. */
> };
>
> union exp_element
> @@ -393,11 +413,7 @@ extern void print_expression (struct exp
>
> extern char *op_string (enum exp_opcode);
>
> -extern void dump_prefix_expression (struct expression *,
> - struct ui_file *,
> - char *);
> -extern void dump_postfix_expression (struct expression *,
> - struct ui_file *,
> - char *);
> +extern void dump_raw_expression (struct expression *, struct ui_file *, char *);
> +extern void dump_prefix_expression (struct expression *, struct ui_file *);
>
> #endif /* !defined (EXPRESSION_H) */
> Index: current-public.25/gdb/f-lang.c
> --- current-public.25/gdb/f-lang.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/h/32_f-lang.c 1.1.1.2.2.1 644)
> +++ submit.16(w)/gdb/f-lang.c Tue, 16 Sep 2003 01:31:54 -0700 hilfingr (GdbPub/h/32_f-lang.c 1.1.1.2.2.3 644)
> @@ -462,9 +462,9 @@ const struct language_defn f_language_de
> range_check_on,
> type_check_on,
> case_sensitive_off,
> + &exp_descriptor_standard,
> f_parse, /* parser */
> f_error, /* parser error function */
> - evaluate_subexp_standard,
> f_printchar, /* Print character constant */
> f_printstr, /* function to print string constant */
> f_emit_char, /* Function to print a single character */
> Index: current-public.25/gdb/jv-lang.c
> --- current-public.25/gdb/jv-lang.c Sat, 13 Sep 2003 23:40:42 -0700 hilfingr (GdbPub/i/30_jv-lang.c 1.1.1.3.3.1.1.1 644)
> +++ submit.16(w)/gdb/jv-lang.c Tue, 16 Sep 2003 01:31:54 -0700 hilfingr (GdbPub/i/30_jv-lang.c 1.1.1.3.3.1.1.1.1.1 644)
> @@ -1030,6 +1030,15 @@ const struct op_print java_op_print_tab[
> {NULL, 0, 0, 0}
> };
>
> +const struct exp_descriptor exp_descriptor_java =
> +{
> + print_subexp_standard,
> + operator_length_standard,
> + op_name_standard,
> + dump_subexp_body_standard,
> + evaluate_subexp_java
> +};
> +
> const struct language_defn java_language_defn =
> {
> "java", /* Language name */
> @@ -1038,9 +1047,9 @@ const struct language_defn java_language
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_java,
> java_parse,
> java_error,
> - evaluate_subexp_java,
> c_printchar, /* Print a character constant */
> c_printstr, /* Function to print string constant */
> java_emit_char, /* Function to print a single character */
> Index: current-public.25/gdb/language.c
> --- current-public.25/gdb/language.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/i/34_language.c 1.1.1.3.1.1.3.1 644)
> +++ submit.16(w)/gdb/language.c Tue, 16 Sep 2003 01:31:53 -0700 hilfingr (GdbPub/i/34_language.c 1.1.1.3.1.1.3.3 644)
> @@ -1267,9 +1267,9 @@ const struct language_defn unknown_langu
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> unk_lang_parser,
> unk_lang_error,
> - evaluate_subexp_standard,
> unk_lang_printchar, /* Print character constant */
> unk_lang_printstr,
> unk_lang_emit_char,
> @@ -1301,9 +1301,9 @@ const struct language_defn auto_language
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> unk_lang_parser,
> unk_lang_error,
> - evaluate_subexp_standard,
> unk_lang_printchar, /* Print character constant */
> unk_lang_printstr,
> unk_lang_emit_char,
> @@ -1334,9 +1334,9 @@ const struct language_defn local_languag
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> unk_lang_parser,
> unk_lang_error,
> - evaluate_subexp_standard,
> unk_lang_printchar, /* Print character constant */
> unk_lang_printstr,
> unk_lang_emit_char,
> Index: current-public.25/gdb/language.h
> --- current-public.25/gdb/language.h Fri, 22 Aug 2003 00:46:52 -0700 hilfingr (GdbPub/i/35_language.h 1.1.1.3.1.1 644)
> +++ submit.16(w)/gdb/language.h Tue, 16 Sep 2003 01:22:12 -0700 hilfingr (GdbPub/i/35_language.h 1.1.1.3.1.1.1.2 644)
> @@ -167,6 +167,11 @@ struct language_defn
> /* Default case sensitivity */
> enum case_sensitivity la_case_sensitivity;
>
> + /* Definitions related to expression printing, prefixifying, and
> + dumping */
> +
> + const struct exp_descriptor *la_exp_desc;
> +
> /* Parser function. */
>
> int (*la_parser) (void);
> @@ -174,10 +179,6 @@ struct language_defn
> /* Parser error function */
>
> void (*la_error) (char *);
> -
> - /* Evaluate an expression. */
> - struct value *(*evaluate_exp) (struct type *, struct expression *,
> - int *, enum noside);
>
> void (*la_printchar) (int ch, struct ui_file * stream);
>
> Index: current-public.25/gdb/m2-lang.c
> --- current-public.25/gdb/m2-lang.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/i/38_m2-lang.c 1.1.1.2.2.1 644)
> +++ submit.16(w)/gdb/m2-lang.c Tue, 16 Sep 2003 01:31:53 -0700 hilfingr (GdbPub/i/38_m2-lang.c 1.1.1.2.2.3 644)
> @@ -415,9 +415,9 @@ const struct language_defn m2_language_d
> range_check_on,
> type_check_on,
> case_sensitive_on,
> + &exp_descriptor_standard,
> m2_parse, /* parser */
> m2_error, /* parser error function */
> - evaluate_subexp_standard,
> m2_printchar, /* Print character constant */
> m2_printstr, /* function to print string constant */
> m2_emit_char, /* Function to print a single character */
> Index: current-public.25/gdb/parse.c
> --- current-public.25/gdb/parse.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/j/29_parse.c 1.1.1.4.3.1 644)
> +++ submit.16(w)/gdb/parse.c Thu, 18 Sep 2003 02:08:40 -0700 hilfingr (GdbPub/j/29_parse.c 1.1.1.4.3.4 644)
> @@ -50,6 +50,17 @@
> #include "gdb_assert.h"
> #include "block.h"
>
> +/* Standard set of definitions for printing, dumping, prefixifying,
> + * and evaluating expressions. */
> +
> +const struct exp_descriptor exp_descriptor_standard =
> + {
> + print_subexp_standard,
> + operator_length_standard,
> + op_name_standard,
> + dump_subexp_body_standard,
> + evaluate_subexp_standard
> + };
> \f
> /* Symbols which architectures can redefine. */
>
> @@ -771,8 +782,7 @@ copy_name (struct stoken token)
> static void
> prefixify_expression (struct expression *expr)
> {
> - int len =
> - sizeof (struct expression) + EXP_ELEM_TO_BYTES (expr->nelts);
> + int len = sizeof (struct expression) + EXP_ELEM_TO_BYTES (expr->nelts);
> struct expression *temp;
> int inpos = expr->nelts, outpos = 0;
>
> @@ -784,18 +794,48 @@ prefixify_expression (struct expression
> prefixify_subexp (temp, expr, inpos, outpos);
> }
>
> -/* Return the number of exp_elements in the subexpression of EXPR
> - whose last exp_element is at index ENDPOS - 1 in EXPR. */
> +/* Return the number of exp_elements in the postfix subexpression
> + of EXPR whose operator is at index ENDPOS - 1 in EXPR. */
>
> int
> length_of_subexp (struct expression *expr, int endpos)
> {
> + int oplen, args, i;
> +
> + operator_length (expr, endpos, &oplen, &args);
> +
> + while (args > 0)
> + {
> + oplen += length_of_subexp (expr, endpos - oplen);
> + args--;
> + }
> +
> + return oplen;
> +}
> +
> +/* Sets *OPLENP to the length of the operator whose (last) index is
> + ENDPOS - 1 in EXPR, and sets *ARGSP to the number of arguments that
> + operator takes. */
> +
> +void
> +operator_length (struct expression *expr, int endpos, int *oplenp, int *argsp)
> +{
> + expr->language_defn->la_exp_desc->operator_length (expr, endpos,
> + oplenp, argsp);
> +}
> +
> +/* Default value for operator_length in exp_descriptor vectors. */
> +
> +void
> +operator_length_standard (struct expression *expr, int endpos,
> + int *oplenp, int *argsp)
> +{
> int oplen = 1;
> int args = 0;
> int i;
>
> if (endpos < 1)
> - error ("?error in length_of_subexp");
> + error ("?error in operator_length_standard");
>
> i = (int) expr->elts[endpos - 1].opcode;
>
> @@ -916,13 +956,8 @@ length_of_subexp (struct expression *exp
> args = 1 + (i < (int) BINOP_END);
> }
>
> - while (args > 0)
> - {
> - oplen += length_of_subexp (expr, endpos - oplen);
> - args--;
> - }
> -
> - return oplen;
> + *oplenp = oplen;
> + *argsp = args;
> }
>
> /* Copy the subexpression ending just before index INEND in INEXPR
> @@ -933,132 +968,13 @@ static void
> prefixify_subexp (struct expression *inexpr,
> struct expression *outexpr, int inend, int outbeg)
> {
> - int oplen = 1;
> - int args = 0;
> + int oplen;
> + int args;
> int i;
> int *arglens;
> enum exp_opcode opcode;
>
> - /* Compute how long the last operation is (in OPLEN),
> - and also how many preceding subexpressions serve as
> - arguments for it (in ARGS). */
> -
> - opcode = inexpr->elts[inend - 1].opcode;
> - switch (opcode)
> - {
> - /* C++ */
> - case OP_SCOPE:
> - oplen = longest_to_int (inexpr->elts[inend - 2].longconst);
> - oplen = 5 + BYTES_TO_EXP_ELEM (oplen + 1);
> - break;
> -
> - case OP_LONG:
> - case OP_DOUBLE:
> - case OP_VAR_VALUE:
> - oplen = 4;
> - break;
> -
> - case OP_TYPE:
> - case OP_BOOL:
> - case OP_LAST:
> - case OP_REGISTER:
> - case OP_INTERNALVAR:
> - oplen = 3;
> - break;
> -
> - case OP_COMPLEX:
> - oplen = 1;
> - args = 2;
> - break;
> -
> - case OP_FUNCALL:
> - case OP_F77_UNDETERMINED_ARGLIST:
> - oplen = 3;
> - args = 1 + longest_to_int (inexpr->elts[inend - 2].longconst);
> - break;
> -
> - case OP_OBJC_MSGCALL: /* Objective C message (method) call */
> - oplen = 4;
> - args = 1 + longest_to_int (inexpr->elts[inend - 2].longconst);
> - break;
> -
> - case UNOP_MIN:
> - case UNOP_MAX:
> - oplen = 3;
> - break;
> -
> - case UNOP_CAST:
> - case UNOP_MEMVAL:
> - oplen = 3;
> - args = 1;
> - break;
> -
> - case UNOP_ABS:
> - case UNOP_CAP:
> - case UNOP_CHR:
> - case UNOP_FLOAT:
> - case UNOP_HIGH:
> - case UNOP_ODD:
> - case UNOP_ORD:
> - case UNOP_TRUNC:
> - oplen = 1;
> - args = 1;
> - break;
> -
> - case STRUCTOP_STRUCT:
> - case STRUCTOP_PTR:
> - case OP_LABELED:
> - args = 1;
> - /* fall through */
> - case OP_M2_STRING:
> - case OP_STRING:
> - case OP_OBJC_NSSTRING: /* Objective C Foundation Class NSString constant */
> - case OP_OBJC_SELECTOR: /* Objective C "@selector" pseudo-op */
> - case OP_NAME:
> - case OP_EXPRSTRING:
> - oplen = longest_to_int (inexpr->elts[inend - 2].longconst);
> - oplen = 4 + BYTES_TO_EXP_ELEM (oplen + 1);
> - break;
> -
> - case OP_BITSTRING:
> - oplen = longest_to_int (inexpr->elts[inend - 2].longconst);
> - oplen = (oplen + HOST_CHAR_BIT - 1) / HOST_CHAR_BIT;
> - oplen = 4 + BYTES_TO_EXP_ELEM (oplen);
> - break;
> -
> - case OP_ARRAY:
> - oplen = 4;
> - args = longest_to_int (inexpr->elts[inend - 2].longconst);
> - args -= longest_to_int (inexpr->elts[inend - 3].longconst);
> - args += 1;
> - break;
> -
> - case TERNOP_COND:
> - case TERNOP_SLICE:
> - case TERNOP_SLICE_COUNT:
> - args = 3;
> - break;
> -
> - case BINOP_ASSIGN_MODIFY:
> - oplen = 3;
> - args = 2;
> - break;
> -
> - /* Modula-2 */
> - case MULTI_SUBSCRIPT:
> - oplen = 3;
> - args = 1 + longest_to_int (inexpr->elts[inend - 2].longconst);
> - break;
> -
> - /* C++ */
> - case OP_THIS:
> - case OP_OBJC_SELF:
> - oplen = 2;
> - break;
> -
> - default:
> - args = 1 + ((int) opcode < (int) BINOP_END);
> - }
> + operator_length (inexpr, inend, &oplen, &args);
>
> /* Copy the final operator itself, from the end of the input
> to the beginning of the output. */
> @@ -1156,14 +1072,13 @@ parse_exp_1 (char **stringptr, struct bl
> parser, to a prefix form. */
>
> if (expressiondebug)
> - dump_prefix_expression (expout, gdb_stdlog,
> - "before conversion to prefix form");
> + dump_raw_expression (expout, gdb_stdlog,
> + "before conversion to prefix form");
>
> prefixify_expression (expout);
>
> if (expressiondebug)
> - dump_postfix_expression (expout, gdb_stdlog,
> - "after conversion to prefix form");
> + dump_prefix_expression (expout, gdb_stdlog);
>
> *stringptr = lexptr;
> return expout;
> Index: current-public.25/gdb/parser-defs.h
> --- current-public.25/gdb/parser-defs.h Tue, 17 Jun 2003 02:35:33 -0700 hilfingr (GdbPub/j/30_parser-def 1.1.1.2 644)
> +++ submit.16(w)/gdb/parser-defs.h Thu, 18 Sep 2003 01:58:16 -0700 hilfingr (GdbPub/j/30_parser-def 1.1.1.2.1.5 644)
> @@ -159,6 +159,17 @@ extern int pop_type_int (void);
>
> extern int length_of_subexp (struct expression *, int);
>
> +extern int dump_subexp (struct expression *, struct ui_file *, int);
> +
> +extern int dump_subexp_body_standard (struct expression *,
> + struct ui_file *, int);
> +
> +extern void operator_length (struct expression *, int, int *, int *);
> +
> +extern void operator_length_standard (struct expression *, int, int *, int *);
> +
> +extern char *op_name_standard (enum exp_opcode);
> +
> extern struct type *follow_types (struct type *);
>
> /* During parsing of a C expression, the pointer to the next character
> @@ -219,6 +230,46 @@ struct op_print
> For a unary operator: 1 iff postfix. */
> int right_assoc;
> };
> +
> +/* Information needed to print, prefixify, and evaluate expressions for
> + a given language. */
> +
> +struct exp_descriptor
> + {
> + /* Print subexpression. */
> + void (*print_subexp) (struct expression *, int *, struct ui_file *,
> + enum precedence);
> +
> + /* Returns number of exp_elements needed to represent an operator and
> + the number of subexpressions it takes. */
> + void (*operator_length) (struct expression*, int, int*, int *);
> +
> + /* Name of this operator for dumping purposes. */
> + char *(*op_name) (enum exp_opcode);
> +
> + /* Dump the rest of this (prefix) expression after the operator
> + itself has been printed. See dump_subexp_body_standard in
> + (expprint.c). */
> + int (*dump_subexp_body) (struct expression *, struct ui_file *, int);
> +
> + /* Evaluate an expression. */
> + struct value *(*evaluate_exp) (struct type *, struct expression *,
> + int *, enum noside);
> + };
> +
> +
> +/* Default descriptor containing standard definitions of all
> + elements. */
> +extern const struct exp_descriptor exp_descriptor_standard;
> +
> +/* Functions used by language-specific extended operators to (recursively)
> + print/dump subexpressions. */
> +
> +extern void print_subexp (struct expression *, int *, struct ui_file *,
> + enum precedence);
> +
> +extern void print_subexp_standard (struct expression *, int *,
> + struct ui_file *, enum precedence);
>
> /* Function used to avoid direct calls to fprintf
> in the code generated by the bison parser. */
> Index: current-public.25/gdb/scm-lang.c
> --- current-public.25/gdb/scm-lang.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/k/14_scm-lang.c 1.1.1.3.2.1 644)
> +++ submit.16(w)/gdb/scm-lang.c Tue, 16 Sep 2003 01:31:52 -0700 hilfingr (GdbPub/k/14_scm-lang.c 1.1.1.3.2.3 644)
> @@ -233,6 +233,15 @@ nosideret:
> return value_from_longest (builtin_type_long, (LONGEST) 1);
> }
>
> +const struct exp_descriptor exp_descriptor_scm =
> +{
> + print_subexp_standard,
> + operator_length_standard,
> + op_name_standard,
> + dump_subexp_body_standard,
> + evaluate_subexp_scm
> +};
> +
> const struct language_defn scm_language_defn =
> {
> "scheme", /* Language name */
> @@ -241,9 +250,9 @@ const struct language_defn scm_language_
> range_check_off,
> type_check_off,
> case_sensitive_off,
> + &exp_descriptor_scm,
> scm_parse,
> c_error,
> - evaluate_subexp_scm,
> scm_printchar, /* Print a character constant */
> scm_printstr, /* Function to print string constant */
> NULL, /* Function to print a single character */
> Index: current-public.25/gdb/objc-lang.c
> --- current-public.25/gdb/objc-lang.c Thu, 11 Sep 2003 02:43:43 -0700 hilfingr (GdbPub/C/b/24_objc-lang. 1.4.3.1 644)
> +++ submit.16(w)/gdb/objc-lang.c Tue, 16 Sep 2003 01:48:04 -0700 hilfingr (GdbPub/C/b/24_objc-lang. 1.4.3.3 644)
> @@ -659,9 +659,9 @@ const struct language_defn objc_language
> range_check_off,
> type_check_off,
> case_sensitive_on,
> + &exp_descriptor_standard,
> objc_parse,
> objc_error,
> - evaluate_subexp_standard,
> objc_printchar, /* Print a character constant */
> objc_printstr, /* Function to print string constant */
> objc_emit_char,
> @@ -1537,8 +1537,8 @@ print_object_command (char *args, int fr
> make_cleanup (free_current_contents, &expr);
> int pc = 0;
>
> - object = expr->language_defn->evaluate_exp (builtin_type_void_data_ptr,
> - expr, &pc, EVAL_NORMAL);
> + object = expr->language_defn->la_exp_desc->evaluate_exp
> + (builtin_type_void_data_ptr, expr, &pc, EVAL_NORMAL);
> do_cleanups (old_chain);
> }
>
>