parse goto, case

This commit is contained in:
pommicket 2022-02-04 22:36:22 -05:00
parent dfce9118b9
commit d75b4154d3
3 changed files with 92 additions and 12 deletions

View file

@ -286,6 +286,7 @@ function parse_statement
token = *8p_token
:stmt_label_loop
if *1token != TOKEN_IDENTIFIER goto stmt_label_loop_end
; if second token in statement is a colon, this must be a label
p = token + 16
if *1p == SYMBOL_COLON goto stmt_label
@ -307,6 +308,8 @@ function parse_statement
if c == KEYWORD_BREAK goto stmt_break
if c == KEYWORD_CONTINUE goto stmt_continue
if c == KEYWORD_RETURN goto stmt_return
if c == KEYWORD_GOTO goto stmt_goto
if c == KEYWORD_CASE goto stmt_case
token_error(token, .str_unrecognized_statement)
:str_unrecognized_statement
@ -317,10 +320,10 @@ function parse_statement
*8p_out = out
return
:stmt_break
write_statement_header(out, STATEMENT_BREAK, token)
token += 16
if *1token != SYMBOL_SEMICOLON goto break_no_semicolon
token += 16
write_statement_header(out, STATEMENT_BREAK, token)
out += 40
goto parse_statement_ret
:break_no_semicolon
@ -329,10 +332,10 @@ function parse_statement
string No semicolon after break.
byte 0
:stmt_continue
write_statement_header(out, STATEMENT_CONTINUE, token)
token += 16
if *1token != SYMBOL_SEMICOLON goto continue_no_semicolon
token += 16
write_statement_header(out, STATEMENT_CONTINUE, token)
out += 40
goto parse_statement_ret
:continue_no_semicolon
@ -340,6 +343,36 @@ function parse_statement
:str_continue_no_semicolon
string No semicolon after continue.
byte 0
:stmt_case
write_statement_header(out, STATEMENT_CASE, token)
token += 16
out += 8
p = token
; @NONSTANDARD
; technically (horribly), this is legal C:
; switch (x) {
; case 1 == 7 ? 5 : 6:
; ...
; }
; we don't handle it properly, even if the conditional is put in parentheses.
; at least it will definitely give an error if it encounters something like this.
:case_find_colon_loop
if *1p == TOKEN_EOF goto case_no_colon
if *1p == SYMBOL_COLON goto case_found_colon
p += 16
goto case_find_colon_loop
:case_found_colon
c = expressions_end
expressions_end = parse_expression(token, p, expressions_end)
evaluate_constant_expression(token, c, &n)
*8out = n
out += 32
token = p + 16
goto parse_statement_ret
:case_no_colon
token_error(token, .str_case_no_colon)
:str_case_no_colon
string No : after case.
:stmt_return
write_statement_header(out, STATEMENT_RETURN, token)
out += 8
@ -352,14 +385,37 @@ function parse_statement
:return_no_expr
out += 32
goto parse_statement_ret
:stmt_goto
write_statement_header(out, STATEMENT_GOTO, token)
out += 8
token += 16
if *1token != TOKEN_IDENTIFIER goto goto_not_ident
token += 8
*8out = *8token
out += 32
token += 8
if *1token != SYMBOL_SEMICOLON goto goto_no_semicolon
token += 16
goto parse_statement_ret
:goto_not_ident
token_error(token, .str_goto_not_ident)
:str_goto_not_ident
string goto not immediately followed by identifier.
byte 0
:goto_no_semicolon
token_error(token, .str_goto_no_semicolon)
:str_goto_no_semicolon
string No semicolon after goto.
byte 0
:stmt_block
write_statement_header(out, STATEMENT_BLOCK, token)
out += 8
local block_p_out
; find the appropriate statement data to use for this block's body
block_p_out = statement_datas_ends
block_p_out += parse_stmt_depth < 3
write_statement_header(out, STATEMENT_BLOCK, token)
out += 8
*8out = *8block_p_out
out += 32
@ -394,7 +450,7 @@ function parse_statement
; empty statement, e.g. while(something)-> ; <-
token += 16 ; skip semicolon
goto parse_statement_ret
function print_statement
argument statement
print_statement_with_depth(statement, 0)
@ -427,11 +483,13 @@ function print_statement_with_depth
dat4 = statement + 32
dat4 = *8dat4
if c == STATEMENT_LABEL goto print_stmt_label
if c == STATEMENT_BLOCK goto print_stmt_block
if c == STATEMENT_CONTINUE goto print_stmt_continue
if c == STATEMENT_BREAK goto print_stmt_break
if c == STATEMENT_RETURN goto print_stmt_return
if c == STATEMENT_GOTO goto print_stmt_goto
if c == STATEMENT_LABEL goto print_stmt_label
if c == STATEMENT_CASE goto print_stmt_case
die(.pristmtNI)
:pristmtNI
@ -480,7 +538,19 @@ function print_statement_with_depth
:print_block_loop_end
putcln('})
return
:print_stmt_goto
puts(.str_goto)
putc(32)
puts(dat1)
puts(.str_semicolon_newline)
return
:print_stmt_case
puts(.str_case)
putc(32)
putn_signed(dat1)
putcln(':)
return
; parse a global variable's initializer
; e.g. int x[5] = {1+8, 2, 3, 4, 5};
; advances *p_token to the token right after the initializer
@ -2367,8 +2437,8 @@ function type_alignof
; evaluate an expression which can be the size of an array, e.g.
; enum { A, B, C };
; int x[A * sizeof(float) + 3 << 5];
; @NONSTANDARD: doesn't handle floats, but really why would you use floats in an array size
; e.g. SomeType x[(int)3.3];
; @NONSTANDARD: doesn't handle floats. this means you can't do
; e.g. double x[] = {1.5,2.3};
; this is also used for #if evaluation
; token is used for error messages (e.g. if this "constant" expression is *x or something)
; NOTE: this returns the end of the expression, not the value (which is stored in *8p_value)