New macro: load-time.

This is similar to the ANSI CL load-time-value.

* eval.c (load_time_s, load_time_lit_s): New symbol variables.
(op_load_time_lit, me_load_time): New static functions.
(eval_init): Intern load-time symbol and sys:load-time-lit.
Register the sys:load-time-lit special operator and load-time
macro.

* share/txr/stdlib/asm.tl (assembler parse-args): We must
now allow the d registers to be the targets of a mov
instruction, because load-time depends on being able to mutate
the data vector, in order to turn the result of a calculation
into a de facto literal.

* share/txr/stdlib/compiler.tl (compiler): New member,
lt-frags.
(compile-in-toplevel): New macro.
(compiler alloc-dreg): New method.
(compiler compile): Handle sys:load-time-lit special form
via comp-load-time-lit method.
(compiler comp-load-time-lit): New method.
(usr:compile-toplevel): Prepend the load-time assembly code
fragments to the compiled assembly code.

* vm.c (vm_set, vm_sm_set): Do not reject an attempt to modify
the static data, since load-time now generates mov
instructions targetting the d registers.

* txr.1: Document load-time.

1 files changed, 0 insertions, 6 deletions

diff --git a/vm.c b/vm.c
index f2dc3bd7..ed22cebb 100644
--- a/vm.c
+++ b/vm.c
@@ -322,9 +322,6 @@ INLINE void vm_set(struct vm_env *dspl, unsigned ref, val newval)
   unsigned i = vm_idx(ref);
   struct vm_env *env = &dspl[d];
 
-  if (d == 1)
-    uw_throwf(error_s, lit("modification of VM static data"), nao);
-
   if (ref == 0)
     uw_throwf(error_s, lit("modification of t00/nil"), nao);
 
@@ -340,9 +337,6 @@ INLINE void vm_sm_set(struct vm_env *dspl, unsigned ref, val newval)
   unsigned i = vm_sm_idx(ref);
   struct vm_env *env = &dspl[d];
 
-  if (d == 1)
-    uw_throwf(error_s, lit("modification of VM static data"), nao);
-
   if (ref == 0)
     uw_throwf(error_s, lit("modification of t00/nil"), nao);