commit 85a39653c8099faad49a56b3b8c03deb621f267e Author: Bertram Felgenhauer Date: Fri May 9 21:30:33 2008 +0200 Fix a bug in the initialisation of local variables. The code was overly eager in combining several variable initialisations into a single F_CLEAR_LOCALS statement. This patch fixes that. This patch also includes a bugfix by Gnomi related to the contexts for inline closures, and an optimization to the clobbered flag handling, also by Gnomi. diff --git a/src/prolang.y b/src/prolang.y index 87be9fd..bc2a116 100644 --- a/src/prolang.y +++ b/src/prolang.y @@ -576,6 +576,10 @@ struct block_scope_s { int first_local; /* Number of first local defined in this scope */ int num_locals; /* Number of locals defined in this scope */ + int num_cleared; + /* Number of locals that have been cleared by earlier CLEAR_LOCALS */ + Bool clobbered; + /* Local variables beyond num_locals may be clobbered */ mp_uint addr; /* Address of CLEAR_LOCALS instruction, needed for backpatching */ }; @@ -2772,6 +2776,8 @@ init_scope (int depth) { block_scope[depth-1].num_locals = 0; block_scope[depth-1].first_local = current_number_of_locals; + block_scope[depth-1].num_cleared = 0; + block_scope[depth-1].clobbered = MY_FALSE; block_scope[depth-1].addr = 0; } /* init_scope() */ @@ -2795,7 +2801,7 @@ enter_block_scope (void) /*-------------------------------------------------------------------------*/ static void -leave_block_scope (void) +leave_block_scope (Bool dontclobber) /* Leave the current scope (if use_local_scopes requires it), freeing * all local names defined in that scope. @@ -2806,6 +2812,13 @@ leave_block_scope (void) { free_local_names(block_depth); block_depth--; + if (block_depth && !dontclobber + && (block_scope[block_depth].num_locals + || block_scope[block_depth].clobbered)) + { + /* the block we just left may have clobbered local variables */ + block_scope[block_depth-1].clobbered = MY_TRUE; + } } } /* leave_block_scope() */ @@ -5142,8 +5155,8 @@ printf("DEBUG: Generate inline closure function:\n"); yyerror("Implementation restriction: Inline closure must not span " "include file limits"); /* Clean up */ - leave_block_scope(); /* Argument scope */ - leave_block_scope(); /* Context scope */ + leave_block_scope(MY_TRUE); /* Argument scope */ + leave_block_scope(MY_TRUE); /* Context scope */ finish_inline_closure(MY_TRUE); return; } @@ -5248,8 +5261,8 @@ printf("DEBUG: -> F_CONTEXT_CLOSURE %d %d\n", current_inline->function, cont /* Clean up */ - leave_block_scope(); /* Argument scope */ - leave_block_scope(); /* Context scope */ + leave_block_scope(MY_TRUE); /* Argument scope */ + leave_block_scope(MY_TRUE); /* Context scope */ finish_inline_closure(MY_FALSE); } /* complete_inline_closure() */ #endif /* USE_NEW_INLINES */ @@ -5969,6 +5982,8 @@ printf("DEBUG: After L_BEGIN_INLINE: program size %ld\n", CURRENT_PROGRAM_SIZE); if (!inline_closure_prototype(9)) YYACCEPT; + + enter_block_scope(); #ifdef DEBUG_INLINES printf("DEBUG: Before comma_expr: program size %ld\n", CURRENT_PROGRAM_SIZE); #endif /* DEBUG_INLINES */ @@ -5982,6 +5997,8 @@ printf("DEBUG: Before comma_expr: program size %ld\n", CURRENT_PROGRAM_SIZE); #ifdef DEBUG_INLINES printf("DEBUG: After L_END_INLINE: program size %ld\n", CURRENT_PROGRAM_SIZE); #endif /* DEBUG_INLINES */ + leave_block_scope(MY_FALSE); + $$.start = current_inline->end; $$.code = -1; $$.type = Type_Closure; @@ -6860,17 +6877,17 @@ block: { block_scope_t *scope = block_scope + block_depth - 1; - if (use_local_scopes && scope->num_locals) + if (use_local_scopes && scope->num_locals > scope->num_cleared) { mem_block[A_PROGRAM].block[scope->addr+2] - = (char)scope->num_locals; + = (char)(scope->num_locals - scope->num_cleared); } } } '}' - { leave_block_scope(); } + { leave_block_scope(MY_FALSE); } ; /* block */ @@ -7491,10 +7508,10 @@ for: { block_scope_t *scope = block_scope + block_depth - 1; - if (use_local_scopes && scope->num_locals) + if (use_local_scopes && scope->num_locals > scope->num_cleared) { mem_block[A_PROGRAM].block[scope->addr+2] - = (char)scope->num_locals; + = (char)(scope->num_locals - scope->num_cleared); } } } @@ -7583,7 +7600,7 @@ for: current_break_address = $3[1]; /* and leave the for scope */ - leave_block_scope(); + leave_block_scope(MY_FALSE); } ; /* for */ @@ -7725,10 +7742,10 @@ foreach: { block_scope_t *scope = block_scope + block_depth - 1; - if (use_local_scopes && scope->num_locals) + if (use_local_scopes && scope->num_locals > scope->num_cleared) { mem_block[A_PROGRAM].block[scope->addr+2] - = (char)scope->num_locals; + = (char)(scope->num_locals - scope->num_cleared); } } @@ -7842,7 +7859,7 @@ foreach: current_break_address = $3[1]; /* and leave the scope */ - leave_block_scope(); + leave_block_scope(MY_FALSE); } ; /* foreach */ @@ -13226,7 +13243,7 @@ inline_fun: ); /* Restore the old locals information */ - leave_block_scope(); + leave_block_scope(MY_TRUE); use_local_scopes = pragma_use_local_scopes; all_locals = save_all_locals; current_number_of_locals = save_current_number_of_locals; @@ -13806,14 +13823,24 @@ printf("DEBUG: context name '%s'\n", get_txt(name->name)); q = redeclare_local(name, actual_type, block_depth); else q = add_local_name(name, actual_type, block_depth); - if (use_local_scopes && scope->num_locals == 1) + + if (use_local_scopes && scope->clobbered) + { + /* finish the previous CLEAR_LOCALS, if any */ + if (scope->num_locals - 1 > scope->num_cleared) + mem_block[A_PROGRAM].block[scope->addr+2] + = (char)(scope->num_locals - 1 - scope->num_cleared); + scope->clobbered = MY_FALSE; + scope->num_cleared = scope->num_locals - 1; + } + if (use_local_scopes && scope->num_locals == scope->num_cleared + 1) { /* First definition of a local, so insert the * clear_locals bytecode and remember its position */ scope->addr = mem_block[A_PROGRAM].current_size; ins_f_code(F_CLEAR_LOCALS); - ins_byte(scope->first_local); + ins_byte(scope->first_local + scope->num_cleared); ins_byte(0); } @@ -13826,14 +13853,24 @@ printf("DEBUG: context name '%s'\n", get_txt(name->name)); else q = add_local_name(name, actual_type, block_depth, MY_FALSE); - if (use_local_scopes && scope->num_locals == 1) + if (use_local_scopes && scope->clobbered) + { + /* finish the previous CLEAR_LOCALS, if any */ + if (scope->num_locals - 1 > scope->num_cleared) + mem_block[A_PROGRAM].block[scope->addr+2] + = (char)(scope->num_locals - 1 - scope->num_cleared); + scope->clobbered = MY_FALSE; + scope->num_cleared = scope->num_locals - 1; + } + + if (use_local_scopes && scope->num_locals == scope->num_cleared + 1) { /* First definition of a local, so insert the * clear_locals bytecode and remember its position */ scope->addr = mem_block[A_PROGRAM].current_size; ins_f_code(F_CLEAR_LOCALS); - ins_byte(scope->first_local); + ins_byte(scope->first_local + scope->num_cleared); ins_byte(0); }