diff options
Diffstat (limited to 'libguile/vm-engine.c')
-rw-r--r-- | libguile/vm-engine.c | 18 |
1 files changed, 13 insertions, 5 deletions
diff --git a/libguile/vm-engine.c b/libguile/vm-engine.c index 22bd39c0e..c90458df6 100644 --- a/libguile/vm-engine.c +++ b/libguile/vm-engine.c @@ -61,23 +61,31 @@ VM_NAME (SCM vm, SCM program, SCM *argv, int nargs) SCM finish_args; /* used both for returns: both in error and normal situations */ #ifdef HAVE_LABELS_AS_VALUES - static void **jump_table = NULL; + static const void **jump_table_pointer = NULL; #endif - + #ifdef HAVE_LABELS_AS_VALUES - if (SCM_UNLIKELY (!jump_table)) + register const void **jump_table JT_REG; + + if (SCM_UNLIKELY (!jump_table_pointer)) { int i; - jump_table = malloc (SCM_VM_NUM_INSTRUCTIONS * sizeof(void*)); + jump_table_pointer = malloc (SCM_VM_NUM_INSTRUCTIONS * sizeof (void*)); for (i = 0; i < SCM_VM_NUM_INSTRUCTIONS; i++) - jump_table[i] = &&vm_error_bad_instruction; + jump_table_pointer[i] = &&vm_error_bad_instruction; #define VM_INSTRUCTION_TO_LABEL 1 +#define jump_table jump_table_pointer #include <libguile/vm-expand.h> #include <libguile/vm-i-system.i> #include <libguile/vm-i-scheme.i> #include <libguile/vm-i-loader.i> +#undef jump_table #undef VM_INSTRUCTION_TO_LABEL } + + /* Attempt to keep JUMP_TABLE_POINTER in a register. This saves one + load instruction at each instruction dispatch. */ + jump_table = jump_table_pointer; #endif /* Initialization */ |