From: Chris Hanson Date: Mon, 23 Aug 2010 09:20:00 +0000 (-0700) Subject: Draft fix for over-shadowing bug. X-Git-Tag: 20101212-Gtk~76^2~3 X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=f55dc7d0bd328f5ccd39d1a0dca13574f9d80ea1;p=mit-scheme.git Draft fix for over-shadowing bug. --- diff --git a/src/microcode/lookup.c b/src/microcode/lookup.c index 93781f63b..83b1499a8 100644 --- a/src/microcode/lookup.c +++ b/src/microcode/lookup.c @@ -78,30 +78,53 @@ USA. #define EXTERNAL_UNASSIGNED_OBJECT \ (VECTOR_REF (fixed_objects, NON_OBJECT)) + +#define PALIST_COND(palist_var) (PAIR_P (*palist_var)) + +#define PALIST_HEADER(palist_var, prefs_var) \ + SCHEME_OBJECT * prefs_var = (PAIR_CDR_LOC (PAIR_CAR (*palist_var))); + +#define PALIST_FOOTER(palist_var) do \ +{ \ + if (PAIR_P (PAIR_CDR (PAIR_CAR (*palist_var)))) \ + palist_var = (PAIR_CDR_LOC (*palist_var)); \ + else \ + (*palist_var) = (PAIR_CDR (*palist_var)); \ +} while (false) + +#define PREFS_COND(prefs_var) (PAIR_P (*prefs_var)) + +#define PREFS_HEADER(prefs_var) \ + PREFS_HEADER_1 (prefs_var, (PAIR_CAR (*prefs_var))) + +#define PREFS_HEADER_1(prefs_var, cache) \ +{ \ + if ((GET_CACHE_REFERENCE_BLOCK (cache)) == SHARP_F) \ + { \ + (*prefs_var) = (PAIR_CDR (*prefs_var)); \ + continue; \ + } \ +} + +#define PREFS_FOOTER(prefs_var) do \ +{ \ + prefs_var = (PAIR_CDR_LOC (*prefs_var)); \ +} while (false) #define WALK_REFERENCES(refs_pointer, ref_var, body) \ { \ SCHEME_OBJECT * WR_palist = (refs_pointer); \ - while (PAIR_P (*WR_palist)) \ + while (PALIST_COND (WR_palist)) \ { \ - SCHEME_OBJECT * WR_prefs \ - = (PAIR_CDR_LOC (PAIR_CAR (*WR_palist))); \ - while (PAIR_P (*WR_prefs)) \ + PALIST_HEADER (WR_palist, WR_prefs); \ + while (PREFS_COND (WR_prefs)) \ { \ SCHEME_OBJECT ref_var = (PAIR_CAR (*WR_prefs)); \ - if ((GET_CACHE_REFERENCE_BLOCK (ref_var)) \ - == SHARP_F) \ - (*WR_prefs) = (PAIR_CDR (*WR_prefs)); \ - else \ - { \ - body; \ - WR_prefs = (PAIR_CDR_LOC (*WR_prefs)); \ - } \ + PREFS_HEADER_1 (WR_prefs, ref_var); \ + body; \ + PREFS_FOOTER (WR_prefs); \ } \ - if (PAIR_P (PAIR_CDR (PAIR_CAR (*WR_palist)))) \ - WR_palist = (PAIR_CDR_LOC (*WR_palist)); \ - else \ - (*WR_palist) = (PAIR_CDR (*WR_palist)); \ + PALIST_FOOTER (WR_palist); \ } \ } @@ -122,9 +145,11 @@ static long unbind_cached_variable static void unbind_variable_1 (SCHEME_OBJECT *, SCHEME_OBJECT, SCHEME_OBJECT); static unsigned long update_cache_refs_space - (SCHEME_OBJECT, SCHEME_OBJECT); + (SCHEME_OBJECT, SCHEME_OBJECT, SCHEME_OBJECT); +static unsigned long update_cache_refs_space_1 + (SCHEME_OBJECT, unsigned int, SCHEME_OBJECT, SCHEME_OBJECT); static long update_cache_references - (SCHEME_OBJECT, SCHEME_OBJECT *, SCHEME_OBJECT); + (SCHEME_OBJECT, SCHEME_OBJECT *, SCHEME_OBJECT, SCHEME_OBJECT); static SCHEME_OBJECT * find_binding_cell (SCHEME_OBJECT, SCHEME_OBJECT, SCHEME_OBJECT *); static SCHEME_OBJECT * scan_frame @@ -157,9 +182,13 @@ static void install_cache static void install_operator_cache (SCHEME_OBJECT, SCHEME_OBJECT, unsigned long); static unsigned long ref_pairs_to_move - (SCHEME_OBJECT *, SCHEME_OBJECT, unsigned long *); + (SCHEME_OBJECT *, SCHEME_OBJECT, SCHEME_OBJECT); +static void delete_ref_pairs + (SCHEME_OBJECT, unsigned int, SCHEME_OBJECT, SCHEME_OBJECT); static void move_ref_pairs - (SCHEME_OBJECT, SCHEME_OBJECT, unsigned int, SCHEME_OBJECT); + (SCHEME_OBJECT, SCHEME_OBJECT, unsigned int, SCHEME_OBJECT, SCHEME_OBJECT); +static SCHEME_OBJECT * new_alist_entry + (SCHEME_OBJECT *, SCHEME_OBJECT); static int move_ref_pair_p (SCHEME_OBJECT, SCHEME_OBJECT); static SCHEME_OBJECT * find_references_named @@ -464,7 +493,7 @@ define_variable (SCHEME_OBJECT environment, SCHEME_OBJECT symbol, GC_CHECK (2 + ((old_cache != SHARP_F) - ? (update_cache_refs_space (old_cache, environment)) + ? (update_cache_refs_space (old_cache, environment, symbol)) : 0)); /* Create the binding. */ @@ -476,7 +505,7 @@ define_variable (SCHEME_OBJECT environment, SCHEME_OBJECT symbol, return ((old_cache != SHARP_F) ? (update_cache_references - (old_cache, (PAIR_CDR_LOC (pair)), environment)) + (old_cache, (PAIR_CDR_LOC (pair)), environment, symbol)) : PRIM_DONE); } } @@ -600,7 +629,7 @@ link_variables (SCHEME_OBJECT target_environment, SCHEME_OBJECT target_symbol, RETURN_IF_ERROR (guarantee_cache (source_cell)); return (define_variable (target_environment, target_symbol, (*source_cell))); } - + #ifdef CC_SUPPORT_P static void move_all_references (SCHEME_OBJECT from_cache, SCHEME_OBJECT to_cache, @@ -688,14 +717,9 @@ unbind_cached_variable (SCHEME_OBJECT * cell, SCHEME_OBJECT frame, SCHEME_OBJECT cache = (GET_TRAP_CACHE (*cell)); SCHEME_OBJECT * shadowed_cell = (find_binding_cell ((GET_FRAME_PARENT (frame)), symbol, 0)); - SCHEME_OBJECT dummy_cell = UNBOUND_OBJECT; - GC_CHECK (update_cache_refs_space (cache, frame)); + GC_CHECK (update_cache_refs_space (cache, frame, symbol)); unbind_variable_1 (cell, frame, symbol); - return - (update_cache_references - (cache, - ((shadowed_cell == 0) ? (&dummy_cell) : shadowed_cell), - frame)); + return (update_cache_references (cache, shadowed_cell, frame, symbol)); } static void @@ -775,6 +799,8 @@ compiler_var_error (SCHEME_OBJECT cache, SCHEME_OBJECT block, ((GET_CACHE_REFERENCES (cache, reference_kind)), reference, { + /* If this reference is in the right block, return the symbol + being referenced. */ if ((GET_CACHE_REFERENCE_BLOCK (reference)) == block) return (PAIR_CAR (PAIR_CAR (*WR_palist))); }); @@ -920,35 +946,32 @@ static void add_reference (SCHEME_OBJECT * palist, SCHEME_OBJECT symbol, SCHEME_OBJECT block, unsigned long offset) { - while (PAIR_P (*palist)) + SCHEME_OBJECT * prefs = (find_references_named (palist, symbol)); + if (prefs != 0) { - if ((PAIR_CAR (PAIR_CAR (*palist))) == symbol) + while (PREFS_COND (prefs)) { - SCHEME_OBJECT * prefs = (PAIR_CDR_LOC (PAIR_CAR (*palist))); - while (PAIR_P (*prefs)) + if ((GET_CACHE_REFERENCE_BLOCK (PAIR_CAR (*prefs))) == SHARP_F) { - if ((GET_CACHE_REFERENCE_BLOCK (PAIR_CAR (*prefs))) == SHARP_F) - { - SET_CACHE_REFERENCE_BLOCK ((PAIR_CAR (*prefs)), block); - SET_CACHE_REFERENCE_OFFSET ((PAIR_CAR (*prefs)), offset); - return; - } - prefs = (PAIR_CDR_LOC (*prefs)); + /* Reuse this pair. */ + SET_CACHE_REFERENCE_BLOCK ((PAIR_CAR (*prefs)), block); + SET_CACHE_REFERENCE_OFFSET ((PAIR_CAR (*prefs)), offset); + return; } - { - SCHEME_OBJECT reference; - DIE_IF_ERROR (make_cache_reference (block, offset, (&reference))); - (*prefs) = (cons (reference, EMPTY_LIST)); - } - return; + PREFS_FOOTER (prefs); } - palist = (PAIR_CDR_LOC (*palist)); + { + SCHEME_OBJECT reference; + DIE_IF_ERROR (make_cache_reference (block, offset, (&reference))); + (*prefs) = (cons (reference, EMPTY_LIST)); + } + return; } { SCHEME_OBJECT reference; DIE_IF_ERROR (make_cache_reference (block, offset, (&reference))); - (*palist) - = (cons ((cons (symbol, (cons (reference, EMPTY_LIST)))), EMPTY_LIST)); + SCHEME_OBJECT alist = (*palist); + (*palist) = (cons ((cons (symbol, (cons (reference, EMPTY_LIST)))), alist)); } } @@ -992,48 +1015,77 @@ install_operator_cache (SCHEME_OBJECT cache, #endif /* CC_SUPPORT_P */ static unsigned long -update_cache_refs_space (SCHEME_OBJECT from_cache, SCHEME_OBJECT environment) +update_cache_refs_space (SCHEME_OBJECT from_cache, SCHEME_OBJECT environment, + SCHEME_OBJECT symbol) { #ifdef CC_SUPPORT_P - unsigned long n_names = 0; - unsigned long n_lookups - = (ref_pairs_to_move ((GET_CACHE_LOOKUP_REFERENCES (from_cache)), - environment, (&n_names))); - unsigned long n_assignments - = (ref_pairs_to_move ((GET_CACHE_ASSIGNMENT_REFERENCES (from_cache)), - environment, (&n_names))); - unsigned long n_operators - = (ref_pairs_to_move ((GET_CACHE_OPERATOR_REFERENCES (from_cache)), - environment, (&n_names))); - - /* No references need to be updated. */ - if (! ((n_lookups == 0) && (n_assignments == 0) && (n_operators == 0))) - return - ((n_operators * SPACE_PER_UUO_LINK) - + (n_names * 4) - + (3 * SPACE_PER_CACHE)); + return + ((update_cache_refs_space_1 + (from_cache, CACHE_REFERENCES_LOOKUP, environment, symbol)) + + (update_cache_refs_space_1 + (from_cache, CACHE_REFERENCES_ASSIGNMENT, environment, symbol)) + + (update_cache_refs_space_1 + (from_cache, CACHE_REFERENCES_OPERATOR, environment, symbol))); +#else + return (0); #endif - - return (PRIM_DONE); } +/* Generate a conservative estimate of the space needed to move some + cache refs from one cache to another. */ + +static unsigned long +update_cache_refs_space_1 (SCHEME_OBJECT from_cache, unsigned int kind, + SCHEME_OBJECT environment, SCHEME_OBJECT symbol) +{ + SCHEME_OBJECT * from_palist = (GET_CACHE_REFERENCES (from_cache, kind)); + unsigned long n_refs = (ref_pairs_to_move (from_palist, environment, symbol)); + unsigned long result = 0; + if (n_refs > 0) + { + /* Space for new cache and new alist entry, if needed. */ + result += (SPACE_PER_CACHE + 4); + if (kind == CACHE_REFERENCES_OPERATOR) + /* space for new trampolines, if needed. */ + result += (n_refs * SPACE_PER_UUO_LINK); + } + return (result); +} + static long update_cache_references (SCHEME_OBJECT from_cache, SCHEME_OBJECT * to_cell, - SCHEME_OBJECT environment) + SCHEME_OBJECT environment, SCHEME_OBJECT symbol) { - DIE_IF_ERROR (guarantee_cache (to_cell)); - { - SCHEME_OBJECT to_cache = (GET_TRAP_CACHE (*to_cell)); + if (to_cell != 0) + { + DIE_IF_ERROR (guarantee_cache (to_cell)); + { + SCHEME_OBJECT to_cache = (GET_TRAP_CACHE (*to_cell)); #ifdef CC_SUPPORT_P - move_ref_pairs - (from_cache, to_cache, CACHE_REFERENCES_LOOKUP, environment); - move_ref_pairs - (from_cache, to_cache, CACHE_REFERENCES_ASSIGNMENT, environment); - move_ref_pairs - (from_cache, to_cache, CACHE_REFERENCES_OPERATOR, environment); + move_ref_pairs + (from_cache, to_cache, CACHE_REFERENCES_LOOKUP, + environment, symbol); + move_ref_pairs + (from_cache, to_cache, CACHE_REFERENCES_ASSIGNMENT, + environment, symbol); + move_ref_pairs + (from_cache, to_cache, CACHE_REFERENCES_OPERATOR, + environment, symbol); +#endif + update_clone (to_cache); + } + } +#ifdef CC_SUPPORT_P + else + { + delete_ref_pairs + (from_cache, CACHE_REFERENCES_LOOKUP, environment, symbol); + delete_ref_pairs + (from_cache, CACHE_REFERENCES_ASSIGNMENT, environment, symbol); + delete_ref_pairs + (from_cache, CACHE_REFERENCES_OPERATOR, environment, symbol); + } #endif - update_clone (to_cache); - } update_clone (from_cache); return (PRIM_DONE); } @@ -1042,74 +1094,80 @@ update_cache_references (SCHEME_OBJECT from_cache, SCHEME_OBJECT * to_cell, static unsigned long ref_pairs_to_move (SCHEME_OBJECT * palist, SCHEME_OBJECT environment, - unsigned long * n_names_ret) + SCHEME_OBJECT symbol) { + SCHEME_OBJECT * prefs = (find_references_named (palist, symbol)); unsigned long n_refs = 0; - while (PAIR_P (*palist)) - { - int any_moved_p = 0; - SCHEME_OBJECT * prefs = (PAIR_CDR_LOC (PAIR_CAR (*palist))); - while (PAIR_P (*prefs)) - if ((GET_CACHE_REFERENCE_BLOCK (PAIR_CAR (*prefs))) == SHARP_F) - (*prefs) = (PAIR_CDR (*prefs)); - else - { - if (move_ref_pair_p ((*prefs), environment)) - { - n_refs += 1; - any_moved_p = 1; - } - prefs = (PAIR_CDR_LOC (*prefs)); - } - if (any_moved_p) - (*n_names_ret) += 1; - palist = (PAIR_CDR_LOC (*palist)); - } + if (prefs != 0) + while (PREFS_COND (prefs)) + { + PREFS_HEADER (prefs); + if (move_ref_pair_p ((*prefs), environment)) + n_refs += 1; + PREFS_FOOTER (prefs); + } return (n_refs); } +static void +delete_ref_pairs (SCHEME_OBJECT from_cache, unsigned int kind, + SCHEME_OBJECT environment, SCHEME_OBJECT symbol) +{ + SCHEME_OBJECT * from_palist = (GET_CACHE_REFERENCES (from_cache, kind)); + SCHEME_OBJECT * from_prefs = (find_references_named (from_palist, symbol)); + if (from_prefs != 0) + while (PREFS_COND (from_prefs)) + { + PREFS_HEADER (from_prefs); + if (move_ref_pair_p ((*from_prefs), environment)) + { + (*from_prefs) = (PAIR_CDR (*from_prefs)); + continue; + } + PREFS_FOOTER (from_prefs); + } +} + static void move_ref_pairs (SCHEME_OBJECT from_cache, SCHEME_OBJECT to_cache, - unsigned int reference_kind, SCHEME_OBJECT environment) + unsigned int reference_kind, SCHEME_OBJECT environment, + SCHEME_OBJECT symbol) { SCHEME_OBJECT * from_palist = (GET_CACHE_REFERENCES (from_cache, reference_kind)); SCHEME_OBJECT * to_palist = (GET_CACHE_REFERENCES (to_cache, reference_kind)); - while (PAIR_P (*from_palist)) - { - SCHEME_OBJECT * from_prefs = (PAIR_CDR_LOC (PAIR_CAR (*from_palist))); - SCHEME_OBJECT symbol = (PAIR_CAR (PAIR_CAR (*from_palist))); - SCHEME_OBJECT * to_prefs = (find_references_named (to_palist, symbol)); - while (PAIR_P (*from_prefs)) + SCHEME_OBJECT * from_prefs = (find_references_named (from_palist, symbol)); + SCHEME_OBJECT * to_prefs = (find_references_named (to_palist, symbol)); + if (from_prefs != 0) + while (PREFS_COND (from_prefs)) + { + PREFS_HEADER (from_prefs); if (move_ref_pair_p ((*from_prefs), environment)) { SCHEME_OBJECT p = (*from_prefs); (*from_prefs) = (PAIR_CDR (p)); if (to_prefs == 0) - { - SCHEME_OBJECT p2; - SET_PAIR_CDR (p, EMPTY_LIST); - p2 = (cons ((cons (symbol, p)), (*to_palist))); - (*to_palist) = p2; - } - else - { - SET_PAIR_CDR (p, (*to_prefs)); - (*to_prefs) = p; - } + to_prefs = (new_alist_entry (to_palist, symbol)); + SET_PAIR_CDR (p, (*to_prefs)); + (*to_prefs) = p; install_cache (to_cache, (GET_CACHE_REFERENCE_BLOCK (PAIR_CAR (p))), (GET_CACHE_REFERENCE_OFFSET (PAIR_CAR (p))), reference_kind); + continue; } - else - from_prefs = (PAIR_CDR_LOC (*from_prefs)); - if (PAIR_P (PAIR_CDR (PAIR_CAR (*from_palist)))) - from_palist = (PAIR_CDR_LOC (*from_palist)); - else - (*from_palist) = (PAIR_CDR (*from_palist)); - } + PREFS_FOOTER (from_prefs); + } +} + +static SCHEME_OBJECT * +new_alist_entry (SCHEME_OBJECT * to_palist, SCHEME_OBJECT symbol) +{ + SCHEME_OBJECT entry = (cons (symbol, EMPTY_LIST)); + SCHEME_OBJECT head = (*to_palist); + (*to_palist) = (cons (entry, head)); + return (PAIR_CDR_LOC (entry)); } static int