From: Turly O'Connor Date: Fri, 21 Dec 2001 10:44:50 +0000 (+0000) Subject: darwin.c (machopic_classify_ident): Handle "stale" section- encoded name problem... X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=b7fb9feb713f47d880d251ff1323e40fc37c14c7;p=gcc.git darwin.c (machopic_classify_ident): Handle "stale" section- encoded name problem to avoid generating illegal stubs. * darwin.c (machopic_classify_ident): Handle "stale" section- encoded name problem to avoid generating illegal stubs. (func_name_maybe_scoped): Remove, not needed for gcc3. (machopic_indirect_call_target): Don't use it. (darwin_encode_section_info): Call only one of update_stubs() or update_non_lazy_ptrs() as DECL cannot be both. (machopic_output_possible_stub_label): New. * darwin.h (ASM_DECLARE_FUNCTION_NAME): Use it. * darwin-protos.h (machopic_output_possible_stub_label): Declare. From-SVN: r48238 --- diff --git a/gcc/config/darwin-protos.h b/gcc/config/darwin-protos.h index 208d93fb7db..0bff1308d01 100644 --- a/gcc/config/darwin-protos.h +++ b/gcc/config/darwin-protos.h @@ -64,6 +64,8 @@ extern void darwin_encode_section_info PARAMS ((tree)); extern void machopic_finish PARAMS ((FILE *)); +extern void machopic_output_possible_stub_label PARAMS ((FILE *, const char*)); + extern void darwin_exception_section PARAMS ((void)); extern void darwin_eh_frame_section PARAMS ((void)); diff --git a/gcc/config/darwin.c b/gcc/config/darwin.c index caf81205588..8e617e9aa82 100644 --- a/gcc/config/darwin.c +++ b/gcc/config/darwin.c @@ -118,6 +118,22 @@ machopic_classify_ident (ident) else if (name[1] == 'T') return MACHOPIC_DEFINED_FUNCTION; + /* It is possible that someone is holding a "stale" name, which has + since been defined. See if there is a "defined" name (i.e, + different from NAME only in having a '!D_' or a '!T_' instead of + a '!d_' or '!t_' prefix) in the identifier hash tables. If so, say + that this identifier is defined. */ + else if (name[1] == 'd' || name[1] == 't') + { + char *new_name; + new_name = (char *)alloca (strlen (name) + 1); + strcpy (new_name, name); + new_name[1] = (name[1] == 'd') ? 'D' : 'T'; + if (maybe_get_identifier (new_name) != NULL) + return (name[1] == 'd') ? MACHOPIC_DEFINED_DATA + : MACHOPIC_DEFINED_FUNCTION; + } + for (temp = machopic_defined_list; temp != NULL_TREE; temp = TREE_CHAIN (temp)) { if (ident == TREE_VALUE (temp)) @@ -527,78 +543,6 @@ machopic_indirect_data_reference (orig, reg) return ptr_ref; } -/* For MACHOPIC_INDIRECT_CALL_TARGET below, we need to beware of: - - extern "C" { int f(); } - struct X { int f(); int g(); }; - int X::f() { ::f(); } - int X::g() { ::f(); f();} - - This is hairy. Both calls to "::f()" need to be indirect (i.e., to - appropriate symbol stubs), but since MACHOPIC_NAME_DEFINED_P calls - GET_IDENTIFIER which treats "f" as "X::f", and "X::f" is indeed (being) - defined somewhere in "X"'s inheritance hierarchy, MACHOPIC_NAME_DEFINED_P - returns TRUE when called with "f", which means that - MACHOPIC_INDIRECT_CALL_TARGET uses an "internal" call instead of an - indirect one as it should. - - Our quick-n-dirty solution to this is to call the following - FUNC_NAME_MAYBE_SCOPED routine which (only for C++) checks whether - FNAME -- the name of the function which we're calling -- is NOT a - mangled C++ name, AND if the current function being compiled is a - method, and if so, use an "external" or "indirect" call. - - Note that this function will be called ONLY when MACHOPIC_INDIRECT_TARGET_P - has already indicated that the target is NOT indirect. - - This conservative solution will sometimes make indirect calls where - it might have been possible to make direct ones. - - FUNC_NAME_MAYBE_SCOPED returns 1 to indicate a "C" name (not scoped), - which in turns means we should create a stub for an indirect call. - */ - -static int is_cplusplus = -1; - -static int -func_name_maybe_scoped (fname) - const char *fname; -{ - - if (is_cplusplus < 0) - is_cplusplus = (strcmp (lang_hooks.name, "GNU C++") == 0); - - if (is_cplusplus) - { - /* If we have a method, then check whether the function we're trying to - call is a "C" function. If so, we should use an indirect call. - - It turns out to be hard to tell whether "we have a method", since - static member functions have a TREE_CODE of FUNCTION_TYPE, as do - namespace-level non-member functions. So here, we always look for - an extern-"C"-like name, and make stubs for them no matter the - calling context. This is temporary, and leaves nagging suspicion - that improvements should be possible here. (I.e., I suspect that - it can still sometimes make stubs where it needn't.) */ - - /* if (1 || TREE_CODE (TREE_TYPE (current_function_decl)) == METHOD_TYPE) */ - { - /* If fname is of the form "f__1X" or "f__Fv", it's C++. */ - while (*fname == '_') ++fname; /* skip leading underscores */ - while (*fname != 0) - { - if (fname[0] == '_' && fname[1] == '_' - && (fname[2] == 'F' || ISDIGIT (fname[2]))) - return 0; - ++fname; - } - /* Not a C++ mangled name: must be "C", in which case play safe. */ - return 1; - } - } - return 0; -} - /* Transform TARGET (a MEM), which is a function call target, to the corresponding symbol_stub if necessary. Return a new MEM. */ @@ -614,7 +558,11 @@ machopic_indirect_call_target (target) enum machine_mode mode = GET_MODE (XEXP (target, 0)); const char *name = XSTR (XEXP (target, 0), 0); - if (!machopic_name_defined_p (name) || func_name_maybe_scoped (name)) + /* If the name is already defined, we need do nothing. */ + if (name[0] == '!' && name[1] == 'T') + return target; + + if (!machopic_name_defined_p (name)) { const char *stub_name = machopic_stub_name (name); @@ -894,6 +842,10 @@ machopic_finish (asm_out_file) if (! TREE_USED (temp)) continue; + /* If the symbol is actually defined, we don't need a stub. */ + if (sym_name[0] == '!' && sym_name[1] == 'T') + continue; + STRIP_NAME_ENCODING (sym_name, sym_name); sym = alloca (strlen (sym_name) + 2); @@ -1056,8 +1008,10 @@ darwin_encode_section_info (decl) } /* The non-lazy pointer list may have captured references to the old encoded name, change them. */ - update_non_lazy_ptrs (XSTR (sym_ref, 0)); - update_stubs (XSTR (sym_ref, 0)); + if (TREE_CODE (decl) == VAR_DECL) + update_non_lazy_ptrs (XSTR (sym_ref, 0)); + else + update_stubs (XSTR (sym_ref, 0)); } /* Scan the list of non-lazy pointers and update any recorded names whose @@ -1090,6 +1044,37 @@ update_non_lazy_ptrs (name) } } +/* Function NAME is being defined, and its label has just been output. + If there's already a reference to a stub for this function, we can + just emit the stub label now and we don't bother emitting the stub later. */ + +void +machopic_output_possible_stub_label (file, name) + FILE *file; + const char *name; +{ + tree temp; + + + /* Ensure we're looking at a section-encoded name. */ + if (name[0] != '!' || (name[1] != 't' && name[1] != 'T')) + return; + + for (temp = machopic_stubs; + temp != NULL_TREE; + temp = TREE_CHAIN (temp)) + { + const char *sym_name; + + sym_name = IDENTIFIER_POINTER (TREE_VALUE (temp)); + if (sym_name[0] == '!' && sym_name[1] == 'T' + && ! strcmp (name+2, sym_name+2)) + { + ASM_OUTPUT_LABEL (file, IDENTIFIER_POINTER (TREE_PURPOSE (temp))); + break; + } + } +} /* Scan the list of stubs and update any recorded names whose stripped name matches the argument. */ diff --git a/gcc/config/darwin.h b/gcc/config/darwin.h index 7988b61a393..3ee493daac7 100644 --- a/gcc/config/darwin.h +++ b/gcc/config/darwin.h @@ -232,6 +232,9 @@ do { text_section (); \ || DECL_INITIAL (DECL)) \ ENCODE_SECTION_INFO (DECL); \ ASM_OUTPUT_LABEL (FILE, xname); \ + /* Avoid generating stubs for functions we've just defined by \ + outputting any required stub name label now. */ \ + machopic_output_possible_stub_label (FILE, xname); \ } while (0) /* Wrap new method names in quotes so the assembler doesn't gag.