diff options
Diffstat (limited to 'libguile/pairs.h')
-rw-r--r-- | libguile/pairs.h | 66 |
1 files changed, 62 insertions, 4 deletions
diff --git a/libguile/pairs.h b/libguile/pairs.h index 6edfc9c3e..130bf28a6 100644 --- a/libguile/pairs.h +++ b/libguile/pairs.h @@ -3,7 +3,7 @@ #ifndef SCM_PAIRS_H #define SCM_PAIRS_H -/* Copyright (C) 1995,1996,2000,2001, 2004, 2006, 2008, 2009, 2010 Free Software Foundation, Inc. +/* Copyright (C) 1995,1996,2000,2001, 2004, 2006, 2008, 2009, 2010, 2012 Free Software Foundation, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License @@ -25,6 +25,8 @@ #include "libguile/__scm.h" +#include "libguile/gc.h" + #if (SCM_DEBUG_PAIR_ACCESSES == 1) @@ -115,11 +117,67 @@ SCM_API void scm_error_pair_access (SCM); #endif -SCM_API SCM scm_cons (SCM x, SCM y); +SCM_INLINE int scm_is_pair (SCM x); +SCM_INLINE SCM scm_cons (SCM x, SCM y); +SCM_INLINE SCM scm_car (SCM x); +SCM_INLINE SCM scm_cdr (SCM x); + +#if SCM_CAN_INLINE || defined SCM_INLINE_C_IMPLEMENTING_INLINES +/* Return a newly allocated pair whose car is @var{x} and whose cdr is + @var{y}. The pair is guaranteed to be different (in the sense of + @code{eq?}) from every previously existing object. */ +SCM_INLINE_IMPLEMENTATION SCM +scm_cons (SCM x, SCM y) +{ + return scm_cell (SCM_UNPACK (x), SCM_UNPACK (y)); +} + +SCM_INLINE_IMPLEMENTATION int +scm_is_pair (SCM x) +{ + /* The following "workaround_for_gcc_295" avoids bad code generated by + i386 gcc 2.95.4 (the Debian packaged 2.95.4-24 at least). + + Under the default -O2 the inlined SCM_I_CONSP test gets "optimized" so + the fetch of the tag word from x is done before confirming it's a + non-immediate (SCM_NIMP). Needless to say that bombs badly if x is a + immediate. This was seen to afflict scm_srfi1_split_at and something + deep in the bowels of ceval(). In both cases segvs resulted from + deferencing a random immediate value. srfi-1.test exposes the problem + through a short list, the immediate being SCM_EOL in that case. + Something in syntax.test exposed the ceval() problem. + + Just "volatile SCM workaround_for_gcc_295 = lst" is enough to avoid the + problem, without even using that variable. The "w=w" is just to + prevent a warning about it being unused. + */ +#if defined (__GNUC__) && __GNUC__ == 2 && __GNUC_MINOR__ == 95 + volatile SCM workaround_for_gcc_295 = x; + workaround_for_gcc_295 = workaround_for_gcc_295; +#endif + + return SCM_I_CONSP (x); +} + +SCM_INLINE_IMPLEMENTATION SCM +scm_car (SCM x) +{ + if (SCM_UNLIKELY (!scm_is_pair (x))) + scm_wrong_type_arg_msg ("car", 0, x, "pair"); + return SCM_CAR (x); +} + +SCM_INLINE_IMPLEMENTATION SCM +scm_cdr (SCM x) +{ + if (SCM_UNLIKELY (!scm_is_pair (x))) + scm_wrong_type_arg_msg ("cdr", 0, x, "pair"); + return SCM_CDR (x); +} +#endif + SCM_API SCM scm_cons2 (SCM w, SCM x, SCM y); SCM_API SCM scm_pair_p (SCM x); -SCM_API SCM scm_car (SCM x); -SCM_API SCM scm_cdr (SCM x); SCM_API SCM scm_set_car_x (SCM pair, SCM value); SCM_API SCM scm_set_cdr_x (SCM pair, SCM value); |