bc: fixes for multi-line if/while/for

function                                             old     new   delta
zbc_vm_process                                       561     589     +28
zbc_lex_next_and_skip_NLINE                            -      22     +22
zbc_parse_stmt_possibly_auto                        2232    2253     +21
zbc_lex_skip_if_at_NLINE                               -      14     +14
zbc_lex_number                                       192     200      +8
zbc_num_divmod                                       150     156      +6
bc_vm_run                                            134     139      +5
bc_vm_init                                           757     760      +3
bc_num_printNewline                                   51      54      +3
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 7/0 up/down: 110/0)             Total: 110 bytes
   text	   data	    bss	    dec	    hex	filename
 982138	    485	   7296	 989919	  f1adf	busybox_old
 982275	    485	   7296	 990056	  f1b68	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2018-12-16 17:30:35 +01:00
parent e9519e44a6
commit 202dd1943c
2 changed files with 45 additions and 8 deletions

View File

@ -3018,6 +3018,29 @@ static BC_STATUS zbc_lex_next(BcLex *l)
# define zbc_lex_next(...) (zbc_lex_next(__VA_ARGS__), BC_STATUS_SUCCESS)
#endif
static BC_STATUS zbc_lex_skip_if_at_NLINE(BcLex *l)
{
if (l->t.t == BC_LEX_NLINE)
RETURN_STATUS(zbc_lex_next(l));
RETURN_STATUS(BC_STATUS_SUCCESS);
}
#if ERRORS_ARE_FATAL
# define zbc_lex_skip_if_at_NLINE(...) (zbc_lex_skip_if_at_NLINE(__VA_ARGS__), BC_STATUS_SUCCESS)
#endif
static BC_STATUS zbc_lex_next_and_skip_NLINE(BcLex *l)
{
BcStatus s;
s = zbc_lex_next(l);
if (s) RETURN_STATUS(s);
// if(cond)<newline>stmt is accepted too (but not 2+ newlines)
s = zbc_lex_skip_if_at_NLINE(l);
RETURN_STATUS(s);
}
#if ERRORS_ARE_FATAL
# define zbc_lex_next_and_skip_NLINE(...) (zbc_lex_next_and_skip_NLINE(__VA_ARGS__), BC_STATUS_SUCCESS)
#endif
static BC_STATUS zbc_lex_text_init(BcLex *l, const char *text)
{
l->buf = text;
@ -4152,7 +4175,8 @@ static BC_STATUS zbc_parse_if(BcParse *p)
if (s) RETURN_STATUS(s);
if (p->l.t.t != BC_LEX_RPAREN) RETURN_STATUS(bc_error_bad_token());
s = zbc_lex_next(&p->l);
// if(cond)<newline>stmt is accepted too (but not 2+ newlines)
s = zbc_lex_next_and_skip_NLINE(&p->l);
if (s) RETURN_STATUS(s);
bc_parse_push(p, BC_INST_JUMP_ZERO);
@ -4216,12 +4240,15 @@ static BC_STATUS zbc_parse_while(BcParse *p)
s = zbc_parse_expr(p, BC_PARSE_REL, bc_parse_next_rel);
if (s) RETURN_STATUS(s);
if (p->l.t.t != BC_LEX_RPAREN) RETURN_STATUS(bc_error_bad_token());
s = zbc_lex_next(&p->l);
// while(cond)<newline>stmt is accepted too
s = zbc_lex_next_and_skip_NLINE(&p->l);
if (s) RETURN_STATUS(s);
bc_parse_push(p, BC_INST_JUMP_ZERO);
bc_parse_pushIndex(p, ip.idx);
//TODO: diagnose "while(cond)<newline><newline>"? Now it is seen as "while() with empty body"
s = zbc_parse_stmt(p);
if (s) RETURN_STATUS(s);
@ -4321,7 +4348,9 @@ static BC_STATUS zbc_parse_for(BcParse *p)
bc_vec_push(&p->exits, &ip);
bc_vec_push(&p->func->labels, &ip.idx);
s = zbc_lex_next(&p->l);
// for(...)<newline>stmt is accepted as well
s = zbc_lex_next_and_skip_NLINE(&p->l);
if (s) RETURN_STATUS(s);
s = zbc_parse_stmt(p);
@ -4453,11 +4482,9 @@ static BC_STATUS zbc_parse_funcdef(BcParse *p)
if (p->l.t.t != BC_LEX_LBRACE)
s = bc_POSIX_requires("the left brace be on the same line as the function header");
// Prevent "define z()<newline>" to be interpreted as function with empty stmt as body
while (p->l.t.t == BC_LEX_NLINE) {
s = zbc_lex_next(&p->l);
if (s) RETURN_STATUS(s);
}
// Prevent "define z()<newline>" from being interpreted as function with empty stmt as body
s = zbc_lex_skip_if_at_NLINE(&p->l);
if (s) RETURN_STATUS(s);
//TODO: GNU bc requires a {} block even if function body has single stmt, enforce this?
p->in_funcdef++; // to determine whether "return" stmt is allowed, and such

View File

@ -56,6 +56,16 @@ testing "bc define with body on next line" \
"8\n9\n" \
"" "define w()\n{ auto z; return 8; }\nw()\n9"
testing "bc if(cond)<NL>" \
"bc" \
"9\n" \
"" "if(0)\n3\n9"
testing "bc while(cond)<NL>" \
"bc" \
"8\n7\n6\n5\n4\n3\n2\n1\n9\n" \
"" "i=9;while(--i)\ni\n9"
tar xJf bc_large.tar.xz
for f in bc*.bc; do