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| author | Andy Wingo <wingo@pobox.com> | 2008-08-05 01:03:17 +0200 |
|---|---|---|
| committer | Andy Wingo <wingo@pobox.com> | 2008-08-05 01:03:17 +0200 |
| commit | 659b4611b6a138fa252a42d1e1a0f4862242454c (patch) | |
| tree | 81ea597791e89aac0e4f850d500acafd7f54820a /m4/labels-as-values.m4 | |
| parent | fbde2b915bfe4139b75e71c4ad5fd701b2558d8f (diff) | |
| download | guile-659b4611b6a138fa252a42d1e1a0f4862242454c.tar.gz | |
re-enable computed goto; fix ,help in the repl; subr dispatch optimizations
* m4/labels-as-values.m4: New file, checks for computed goto.
* configure.in: Use AC_C_LABELS_AS_VALUES.
* module/system/repl/command.scm (procedure-documentation): Extend the
core's procedure-documentation in an ad-hoc way, so that ,help works.
* module/system/vm/core.scm (program-properties): New function.
(program-documentation): New function.
* src/vm_engine.h (DROP, DROPN): Decrement sp before checking for
underflow.
* src/vm_system.c (call, tail-call): Add some optimized dispatch for some
C functions, so that we can avoid consing and the interpreter if
possible. However currently it seems that I'm always getting the
scm_call_* trampolines back.
Diffstat (limited to 'm4/labels-as-values.m4')
| -rw-r--r-- | m4/labels-as-values.m4 | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/m4/labels-as-values.m4 b/m4/labels-as-values.m4 new file mode 100644 index 000000000..eedfb553a --- /dev/null +++ b/m4/labels-as-values.m4 @@ -0,0 +1,22 @@ +dnl check for gcc's "labels as values" feature +AC_DEFUN(AC_C_LABELS_AS_VALUES, +[AC_CACHE_CHECK([labels as values], ac_cv_labels_as_values, +[AC_TRY_COMPILE([ +int foo(int); +int foo(i) +int i; { +static void *label[] = { &&l1, &&l2 }; +goto *label[i]; +l1: return 1; +l2: return 2; +} +], +[int i;], +ac_cv_labels_as_values=yes, +ac_cv_labels_as_values=no)]) +if test "$ac_cv_labels_as_values" = yes; then +AC_DEFINE(HAVE_LABELS_AS_VALUES, [], + [Define if compiler supports gcc's "labels as values" (aka computed goto) + feature, used to speed up instruction dispatch in the interpreter.]) +fi +]) |