This allows us to save and restore callee-save temporaries, i.e. RBP on
32-bit x86. Otherwise it's a disaster shuffling stack arguments using
temporaries.
The x32 ABI (i.e., amd64 with 32-bit pointers) is mostly a C language
question. From a JIT perspective it mostly looks just like amd64. We
can fix any differences in a followup, but x32 is also a pretty dead
ABI, so I feel OK with this.
* libguile/programs.c (scm_i_program_name): Use scm_i_primitive_name for
primitives. No functional change though.
* libguile/vm.c (DEFINE_BUILTIN): Mark builtins as primitives.
The register structures just contain the regno. Since the only flag is
the callee-save flag, we can punt that to a separate per-backend,
per-target predicate.
Now that there's no hazard to using a register used for passing
arguments, renumber to give JIT_R/JIT_F/JIT_V names to all registers.
Choose a temp register that's not used for passing arguments. Our
previous choice was an argument register (doh!) which made function
calls with many arguments fail.
* libguile/jit.c: Operands have their ABI in them. We can now have
addends on GPR and MEM operands, which can improve register
allocation. Use new jit_calli_3, etc helper APIs.
The motivation for this change is that SCM_MAKE_CHAR is sometimes passed
an expression that involves a procedure call that is not always trivial.
In other cases, the results are not guaranteed to be the same both
times, which could lead to the creation of invalid SCM objects.
* libguile/chars.h (SCM_MAKE_CHAR): Reimplement.
* libguile/scmsigs.c (signal_delivery_thread): Call scm_async_tick to
give any pending asyncs a chance to run before we block indefinitely
waiting for a signal to arrive.
Reported by Jeffrey Walton <noloader@gmail.com> in
<https://lists.gnu.org/archive/html/guile-devel/2019-03/msg00001.html>.
Note that C11 section 7.1.4 (Use of library functions) states that:
"unless explicitly stated otherwise in the detailed descriptions [of
library functions] that follow: If an argument to a function has an
invalid value (such as ... a null pointer ...) ..., the behavior is
undefined." Note that 'strxfrm' is an example of a standard C function
that explicitly states otherwise, allowing NULL to be passed in the
first argument if the size argument is zero, but no similar allowance is
specified for 'memcpy' or 'memcmp'.
* libguile/bytevectors.c (scm_uniform_array_to_bytevector): Call memcpy
only if 'byte_len' is non-zero.
* libguile/srfi-14.c (charsets_equal): Call memcmp only if the number of
ranges is non-zero.
* libguile/stime.c (setzone): Pass 1-character buffer to
'scm_to_locale_stringbuf', instead of NULL.
* libguile/strings.c (scm_to_locale_stringbuf): Call memcpy only if the
number of bytes to copy is non-zero.
