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Additional parsing in function/sub; emission of prolog/epilog code
author lost@l-w.ca
date Thu, 27 Jan 2011 20:44:57 -0700
parents 87590f43e76d
children 77626fc37af2
comparison
equal deleted inserted replaced
25:87590f43e76d 26:26aa76da75ad
22 /* 22 /*
23 This is the actual compiler bit; it drives the parser and code generation 23 This is the actual compiler bit; it drives the parser and code generation
24 */ 24 */
25 25
26 #include <stdio.h> 26 #include <stdio.h>
27
28 #include <lw_alloc.h>
29 #include <lw_string.h>
27 30
28 #include "lwbasic.h" 31 #include "lwbasic.h"
29 32
30 /* parse a type; the next token will be acquired as a result */ 33 /* parse a type; the next token will be acquired as a result */
31 /* the token advancement is to provide consistency */ 34 /* the token advancement is to provide consistency */
50 53
51 /* issub means RETURNS is not allowed; !issub means RETURNS is required */ 54 /* issub means RETURNS is not allowed; !issub means RETURNS is required */
52 static void parse_subfunc(cstate *state, int issub) 55 static void parse_subfunc(cstate *state, int issub)
53 { 56 {
54 int pt; 57 int pt;
55 58 char *subname;
59 int vis = 0;
60
56 lexer(state); 61 lexer(state);
57 if (state -> lexer_token != token_identifier) 62 if (state -> lexer_token != token_identifier)
58 { 63 {
59 lwb_error("Invalid sub name '%s'", state -> lexer_token_string); 64 lwb_error("Invalid sub name '%s'", state -> lexer_token_string);
60 } 65 }
61 66
62 printf("<name> = %s\n", state -> lexer_token_string); 67 subname = lw_strdup(state -> lexer_token_string);
63 68
64 lexer(state); 69 lexer(state);
65 if (state -> lexer_token == token_kw_public || state -> lexer_token == token_kw_private) 70 if (state -> lexer_token == token_kw_public || state -> lexer_token == token_kw_private)
66 { 71 {
67 printf("<type> = %s\n", state -> lexer_token_string); 72 if (state -> lexer_token == token_kw_public)
73 vis = 1;
68 lexer(state); 74 lexer(state);
69 } 75 }
70 76
71 /* ignore the "PARAMS" keyword if present */ 77 /* ignore the "PARAMS" keyword if present */
72 if (state -> lexer_token == token_kw_params) 78 if (state -> lexer_token == token_kw_params)
73 lexer(state); 79 lexer(state);
74 80
75 if (state -> lexer_token == token_eol) 81 if (state -> lexer_token == token_eol || state -> lexer_token == token_kw_returns)
76 goto noparms; 82 goto noparms;
77 83
78 paramagain: 84 paramagain:
79 if (state -> lexer_token != token_identifier) 85 if (state -> lexer_token != token_identifier)
80 { 86 {
81 lwb_error("Parameter name expected, get %d, %s\n", state -> lexer_token, state -> lexer_token_string); 87 lwb_error("Parameter name expected, got %d, %s\n", state -> lexer_token, state -> lexer_token_string);
82 } 88 }
83 printf("Got <param> = %s\n", state -> lexer_token_string); 89 printf("Got <param> = %s\n", state -> lexer_token_string);
84 lexer(state); 90 lexer(state);
85 91
86 if (state -> lexer_token != token_kw_as) 92 if (state -> lexer_token != token_kw_as)
128 134
129 if (state -> lexer_token != token_eol) 135 if (state -> lexer_token != token_eol)
130 { 136 {
131 lwb_error("EOL expected; found %d, %s\n", state -> lexer_token, state -> lexer_token_string); 137 lwb_error("EOL expected; found %d, %s\n", state -> lexer_token, state -> lexer_token_string);
132 } 138 }
139
140
141 printf("Sub/Func %s, vis %s\n", subname, vis ? "public" : "private");
142
143 state -> currentsub = subname;
144
145 /* consume EOL */
146 lexer(state);
147
148 /* variable declarations */
149 /* parse_decls(state); */
150
151 /* output function/sub prolog */
152 emit_prolog(state, vis, 0);
153
154 /* parse statement block */
155 /* parse_statemetns(state); */
156
157 if (issub)
158 {
159 if (state -> lexer_token != token_kw_endsub)
160 {
161 lwb_error("Expecting ENDSUB, got %d (%s)\n", state -> lexer_token, state -> lexer_token_string);
162 }
163 }
164 else
165 {
166 if (state -> lexer_token != token_kw_endfunction)
167 {
168 lwb_error("Expecting ENDFUNCTION, got %d (%s)\n", state -> lexer_token, state -> lexer_token_string);
169 }
170 }
171 /* output function/sub epilog */
172 emit_epilog(state);
173
174 lw_free(state -> currentsub);
175 state -> currentsub = NULL;
176
133 } 177 }
134 178
135 void compiler(cstate *state) 179 void compiler(cstate *state)
136 { 180 {
137 state -> lexer_curchar = -1; 181 state -> lexer_curchar = -1;