X-Git-Url: http://git.subgeniuskitty.com/vvhitespace/.git/blobdiff_plain/eea0db3fe145a963cc85df6e5785c9bcc54b63ab..a805b721f73268be338edf99ed09f03ac842ef2e:/vv_interpreter.c diff --git a/vv_interpreter.c b/vv_interpreter.c index 337fd61..6dde3e8 100644 --- a/vv_interpreter.c +++ b/vv_interpreter.c @@ -118,10 +118,18 @@ parse_label(uint8_t * code, size_t * pc) uint8_t c; while ((c = code[(*pc)++]) != '\n') { label = label << 1; - if (c == ' ') label++; + if (c == '\t') label++; + } + return label; +} + +uint16_t +check_label(size_t * labels, uint16_t label, size_t * pc) +{ + if (!labels[label]) { + fprintf(stderr, "Trying to process label 0x%X.\n", label); + ws_die(pc, "uninitialized label (forgot an include?)"); } - // TODO: Where should I handle attempts to access an unitialized label? - // For now, leave it undefined in a nasal demon sense. return label; } @@ -130,11 +138,10 @@ populate_labels(size_t * labels, uint8_t * code, size_t code_size) { size_t cp = 0; while (cp <= code_size) { - if (code[cp] == '\v') { + if (code[cp++] == '\v') { uint16_t temp_label = parse_label(code, &cp); labels[temp_label] = cp; } - cp++; } } @@ -248,6 +255,7 @@ void process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * labels, size_t ** rsp) { + size_t temp_pc; switch (next_code_byte(code,pc)) { case '\n': /* Technically another LF is required but we ignore it. */ @@ -266,15 +274,13 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * lab break; case '\t': /* Call a subroutine. */ - { - size_t temp_pc = labels[parse_label(code, pc)]; - *((*rsp)++) = *pc; - *pc = temp_pc; - } + temp_pc = labels[check_label(labels, parse_label(code, pc), pc)]; + *((*rsp)++) = *pc; + *pc = temp_pc; break; case '\n': /* Jump unconditionally to a label. */ - *pc = labels[parse_label(code, pc)]; + *pc = labels[check_label(labels, parse_label(code, pc), pc)]; break; default: ws_die(pc, "malformed flow control IMP"); @@ -287,11 +293,13 @@ process_imp_flowcontrol(uint8_t * code, size_t * pc, int64_t ** sp, size_t * lab switch (next_code_byte(code,pc)) { case ' ': /* Jump to a label if TOS == 0 */ - if (stack_pop(sp) == 0) *pc = labels[parse_label(code, pc)]; + temp_pc = labels[check_label(labels, parse_label(code, pc), pc)]; + if (stack_pop(sp) == 0) *pc = temp_pc; break; case '\t': /* Jump to a label if TOS < 0. */ - if (stack_pop(sp) < 0) *pc = labels[parse_label(code, pc)]; + temp_pc = labels[check_label(labels, parse_label(code, pc), pc)]; + if (stack_pop(sp) < 0) *pc = temp_pc; break; case '\n': /* Return from subroutine. */