From a9fa03de24ded52ad8f1ccac7757dd34df5ad377 Mon Sep 17 00:00:00 2001 From: Adam Fedor Date: Wed, 30 Apr 2003 01:27:53 +0000 Subject: [PATCH] * eval.c (evaluate_subexp_standard): Handle ObjC ops. * infcall.c (find_function_addr): Make non-static. * infcall.h (find_function_addr): Declare. * Makefile.in (eval.o): Update dependencies. --- gdb/ChangeLog | 7 ++ gdb/Makefile.in | 2 +- gdb/eval.c | 284 ++++++++++++++++++++++++++++++++++++++++++++++++ gdb/infcall.c | 2 +- gdb/infcall.h | 4 + 5 files changed, 297 insertions(+), 2 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index d7b46202395..e211fa16fff 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,10 @@ +2003-04-29 Adam Fedor + + * eval.c (evaluate_subexp_standard): Handle ObjC ops. + * infcall.c (find_function_addr): Make non-static. + * infcall.h (find_function_addr): Declare. + * Makefile.in (eval.o): Update dependencies. + 2003-04-28 Adam Fedor * symtab.c (symbol_find_demangled_name): Check for and demangle diff --git a/gdb/Makefile.in b/gdb/Makefile.in index 3707de27f96..46c25e6ab4a 100644 --- a/gdb/Makefile.in +++ b/gdb/Makefile.in @@ -1687,7 +1687,7 @@ elfread.o: elfread.c $(defs_h) $(bfd_h) $(gdb_string_h) $(elf_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) + $(f_lang_h) $(cp_abi_h) $(infcall_h) $(objc-lang.h) $(block_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) \ diff --git a/gdb/eval.c b/gdb/eval.c index af93ce9cda6..c266cd1e33e 100644 --- a/gdb/eval.c +++ b/gdb/eval.c @@ -33,6 +33,8 @@ #include "f-lang.h" /* for array bound stuff */ #include "cp-abi.h" #include "infcall.h" +#include "objc-lang.h" +#include "block.h" /* Defined in symtab.c */ extern int hp_som_som_object_present; @@ -472,6 +474,15 @@ evaluate_subexp_standard (struct type *expect_type, goto nosideret; return value_string (&exp->elts[pc + 2].string, tem); + case OP_OBJC_NSSTRING: /* Objective C Foundation Class NSString constant. */ + tem = longest_to_int (exp->elts[pc + 1].longconst); + (*pos) += 3 + BYTES_TO_EXP_ELEM (tem + 1); + if (noside == EVAL_SKIP) + { + goto nosideret; + } + return (struct value *) value_nsstring (&exp->elts[pc + 2].string, tem + 1); + case OP_BITSTRING: tem = longest_to_int (exp->elts[pc + 1].longconst); (*pos) @@ -668,6 +679,275 @@ evaluate_subexp_standard (struct type *expect_type, return arg2; } + case OP_OBJC_SELECTOR: + { /* Objective C @selector operator. */ + char *sel = &exp->elts[pc + 2].string; + int len = longest_to_int (exp->elts[pc + 1].longconst); + + (*pos) += 3 + BYTES_TO_EXP_ELEM (len + 1); + if (noside == EVAL_SKIP) + goto nosideret; + + if (sel[len] != 0) + sel[len] = 0; /* Make sure it's terminated. */ + return value_from_longest (lookup_pointer_type (builtin_type_void), + lookup_child_selector (sel)); + } + + case OP_OBJC_MSGCALL: + { /* Objective C message (method) call. */ + + static unsigned long responds_selector = 0; + static unsigned long method_selector = 0; + + unsigned long selector = 0; + + int using_gcc = 0; + int struct_return = 0; + int sub_no_side = 0; + + static struct value *msg_send = NULL; + static struct value *msg_send_stret = NULL; + static int gnu_runtime = 0; + + struct value *target = NULL; + struct value *method = NULL; + struct value *called_method = NULL; + + struct type *selector_type = NULL; + + struct value *ret = NULL; + CORE_ADDR addr = 0; + + selector = exp->elts[pc + 1].longconst; + nargs = exp->elts[pc + 2].longconst; + argvec = (struct value **) alloca (sizeof (struct value *) + * (nargs + 5)); + + (*pos) += 3; + + selector_type = lookup_pointer_type (builtin_type_void); + if (noside == EVAL_AVOID_SIDE_EFFECTS) + sub_no_side = EVAL_NORMAL; + else + sub_no_side = noside; + + target = evaluate_subexp (selector_type, exp, pos, sub_no_side); + + if (value_as_long (target) == 0) + return value_from_longest (builtin_type_long, 0); + + if (lookup_minimal_symbol ("objc_msg_lookup", 0, 0)) + gnu_runtime = 1; + + /* Find the method dispatch (Apple runtime) or method lookup + (GNU runtime) function for Objective-C. These will be used + to lookup the symbol information for the method. If we + can't find any symbol information, then we'll use these to + call the method, otherwise we can call the method + directly. The msg_send_stret function is used in the special + case of a method that returns a structure (Apple runtime + only). */ + if (gnu_runtime) + { + msg_send = find_function_in_inferior ("objc_msg_lookup"); + msg_send_stret = find_function_in_inferior ("objc_msg_lookup"); + } + else + { + msg_send = find_function_in_inferior ("objc_msgSend"); + /* Special dispatcher for methods returning structs */ + msg_send_stret = find_function_in_inferior ("objc_msgSend_stret"); + } + + /* Verify the target object responds to this method. The + standard top-level 'Object' class uses a different name for + the verification method than the non-standard, but more + often used, 'NSObject' class. Make sure we check for both. */ + + responds_selector = lookup_child_selector ("respondsToSelector:"); + if (responds_selector == 0) + responds_selector = lookup_child_selector ("respondsTo:"); + + if (responds_selector == 0) + error ("no 'respondsTo:' or 'respondsToSelector:' method"); + + method_selector = lookup_child_selector ("methodForSelector:"); + if (method_selector == 0) + method_selector = lookup_child_selector ("methodFor:"); + + if (method_selector == 0) + error ("no 'methodFor:' or 'methodForSelector:' method"); + + /* Call the verification method, to make sure that the target + class implements the desired method. */ + + argvec[0] = msg_send; + argvec[1] = target; + argvec[2] = value_from_longest (builtin_type_long, responds_selector); + argvec[3] = value_from_longest (builtin_type_long, selector); + argvec[4] = 0; + + ret = call_function_by_hand (argvec[0], 3, argvec + 1); + if (gnu_runtime) + { + /* Function objc_msg_lookup returns a pointer. */ + argvec[0] = ret; + ret = call_function_by_hand (argvec[0], 3, argvec + 1); + } + if (value_as_long (ret) == 0) + error ("Target does not respond to this message selector."); + + /* Call "methodForSelector:" method, to get the address of a + function method that implements this selector for this + class. If we can find a symbol at that address, then we + know the return type, parameter types etc. (that's a good + thing). */ + + argvec[0] = msg_send; + argvec[1] = target; + argvec[2] = value_from_longest (builtin_type_long, method_selector); + argvec[3] = value_from_longest (builtin_type_long, selector); + argvec[4] = 0; + + ret = call_function_by_hand (argvec[0], 3, argvec + 1); + if (gnu_runtime) + { + argvec[0] = ret; + ret = call_function_by_hand (argvec[0], 3, argvec + 1); + } + + /* ret should now be the selector. */ + + addr = value_as_long (ret); + if (addr) + { + struct symbol *sym = NULL; + /* Is it a high_level symbol? */ + + sym = find_pc_function (addr); + if (sym != NULL) + method = value_of_variable (sym, 0); + } + + /* If we found a method with symbol information, check to see + if it returns a struct. Otherwise assume it doesn't. */ + + if (method) + { + struct block *b; + CORE_ADDR funaddr; + struct type *value_type; + + funaddr = find_function_addr (method, &value_type); + + b = block_for_pc (funaddr); + + /* If compiled without -g, assume GCC 2. */ + using_gcc = (b == NULL ? 2 : BLOCK_GCC_COMPILED (b)); + + CHECK_TYPEDEF (value_type); + + if ((value_type == NULL) + || (TYPE_CODE(value_type) == TYPE_CODE_ERROR)) + { + if (expect_type != NULL) + value_type = expect_type; + } + + struct_return = using_struct_return (method, funaddr, value_type, using_gcc); + } + else if (expect_type != NULL) + { + struct_return = using_struct_return (NULL, addr, check_typedef (expect_type), using_gcc); + } + + /* Found a function symbol. Now we will substitute its + value in place of the message dispatcher (obj_msgSend), + so that we call the method directly instead of thru + the dispatcher. The main reason for doing this is that + we can now evaluate the return value and parameter values + according to their known data types, in case we need to + do things like promotion, dereferencing, special handling + of structs and doubles, etc. + + We want to use the type signature of 'method', but still + jump to objc_msgSend() or objc_msgSend_stret() to better + mimic the behavior of the runtime. */ + + if (method) + { + if (TYPE_CODE (VALUE_TYPE (method)) != TYPE_CODE_FUNC) + error ("method address has symbol information with non-function type; skipping"); + if (struct_return) + VALUE_ADDRESS (method) = value_as_address (msg_send_stret); + else + VALUE_ADDRESS (method) = value_as_address (msg_send); + called_method = method; + } + else + { + if (struct_return) + called_method = msg_send_stret; + else + called_method = msg_send; + } + + if (noside == EVAL_SKIP) + goto nosideret; + + if (noside == EVAL_AVOID_SIDE_EFFECTS) + { + /* If the return type doesn't look like a function type, + call an error. This can happen if somebody tries to + turn a variable into a function call. This is here + because people often want to call, eg, strcmp, which + gdb doesn't know is a function. If gdb isn't asked for + it's opinion (ie. through "whatis"), it won't offer + it. */ + + struct type *type = VALUE_TYPE (called_method); + if (type && TYPE_CODE (type) == TYPE_CODE_PTR) + type = TYPE_TARGET_TYPE (type); + type = TYPE_TARGET_TYPE (type); + + if (type) + { + if ((TYPE_CODE (type) == TYPE_CODE_ERROR) && expect_type) + return allocate_value (expect_type); + else + return allocate_value (type); + } + else + error ("Expression of type other than \"method returning ...\" used as a method"); + } + + /* Now depending on whether we found a symbol for the method, + we will either call the runtime dispatcher or the method + directly. */ + + argvec[0] = called_method; + argvec[1] = target; + argvec[2] = value_from_longest (builtin_type_long, selector); + /* User-supplied arguments. */ + for (tem = 0; tem < nargs; tem++) + argvec[tem + 3] = evaluate_subexp_with_coercion (exp, pos, noside); + argvec[tem + 3] = 0; + + if (gnu_runtime && (method != NULL)) + { + ret = call_function_by_hand (argvec[0], nargs + 2, argvec + 1); + /* Function objc_msg_lookup returns a pointer. */ + argvec[0] = ret; + ret = call_function_by_hand (argvec[0], nargs + 2, argvec + 1); + } + else + ret = call_function_by_hand (argvec[0], nargs + 2, argvec + 1); + + return ret; + } + break; + case OP_FUNCALL: (*pos) += 2; op = exp->elts[*pos].opcode; @@ -1750,6 +2030,10 @@ evaluate_subexp_standard (struct type *expect_type, (*pos) += 1; return value_of_this (1); + case OP_OBJC_SELF: + (*pos) += 1; + return value_of_local ("self", 1); + case OP_TYPE: error ("Attempt to use a type name as an expression"); diff --git a/gdb/infcall.c b/gdb/infcall.c index f87d3ba3258..1ce22fb1c6c 100644 --- a/gdb/infcall.c +++ b/gdb/infcall.c @@ -157,7 +157,7 @@ value_arg_coerce (struct value *arg, struct type *param_type, /* Determine a function's address and its return type from its value. Calls error() if the function is not valid for calling. */ -static CORE_ADDR +CORE_ADDR find_function_addr (struct value *function, struct type **retval_type) { register struct type *ftype = check_typedef (VALUE_TYPE (function)); diff --git a/gdb/infcall.h b/gdb/infcall.h index 03774111b8c..05d06e034bf 100644 --- a/gdb/infcall.h +++ b/gdb/infcall.h @@ -23,6 +23,10 @@ #define INFCALL_H struct value; +struct type; + +extern CORE_ADDR find_function_addr (struct value *function, + struct type **retval_type); /* Perform a function call in the inferior. -- 2.30.2