[Milkymist-devel] [PATCH 03/11] libfpvm: pass token in struct ast_node

[Werner Almesberger]

This will help with further optimizations.
---
 software/libfpvm/ast.h           |    8 +++++++-
 software/libfpvm/parser.y        |   31 +++++++++++++++++--------------
 software/libfpvm/parser_helper.c |    8 +++++---
 3 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/software/libfpvm/ast.h b/software/libfpvm/ast.h
index e096681..9394c73 100644
--- a/software/libfpvm/ast.h
+++ b/software/libfpvm/ast.h
@@ -22,6 +22,11 @@
 
 #define IDENTIFIER_SIZE 24
 
+struct id {
+       int token;
+       char label[IDENTIFIER_SIZE];
+};
+
 /* maximum supported arity is 3 */
 struct ast_branches {
        struct ast_node *a;
@@ -30,6 +35,7 @@ struct ast_branches {
 };
 
 struct ast_node {
+       int token;
        /*
         * label is an empty string:
         *   node is a constant
@@ -47,6 +53,6 @@ struct ast_node {
 
 void *ParseAlloc(void *(*mallocProc)(size_t));
 void ParseFree(void *p, void (*freeProc)(void*));
-void Parse(void *yyp, int yymajor, void *yyminor, struct ast_node **p);
+void Parse(void *yyp, int yymajor, struct id *yyminor, struct ast_node **p);
 
 #endif /* __AST_H */
diff --git a/software/libfpvm/parser.y b/software/libfpvm/parser.y
index be57316..42dfd1e 100644
--- a/software/libfpvm/parser.y
+++ b/software/libfpvm/parser.y
@@ -22,14 +22,16 @@
        #include <malloc.h>
        #include <math.h>
        #include "ast.h"
+       #include "parser.h"
 
 
-       struct ast_node *node(const char *id, struct ast_node *a,
+       struct ast_node *node(int token, const char *id, struct ast_node *a,
             struct ast_node *b, struct ast_node *c)
        {
                struct ast_node *n;
 
                n = malloc(sizeof(struct ast_node));
+               n->token = token;
                strncpy(n->label, id, sizeof(n->label));
                n->label[sizeof(n->label)-1] = 0;
                n->contents.branches.a = a;
@@ -41,10 +43,11 @@
 
 %start_symbol start
 %extra_argument {struct ast_node **parseout}
-%token_type {void *}
+%token_type {struct id *}
 
 %token_destructor { free($$); }
 
+%type start {struct ast_node *}
 %type node {struct ast_node *}
 %destructor node { free($$); }
 
@@ -54,12 +57,12 @@ start(S) ::= node(N). {
 }
 
 node(N) ::= TOK_CONSTANT(C). {
-       N = node("", NULL, NULL, NULL);
-       N->contents.constant = atof(C);
+       N = node(TOK_CONSTANT, "", NULL, NULL, NULL);
+       N->contents.constant = atof(C->label);
 }
 
 node(N) ::= ident(I). {
-       N = node(I, NULL, NULL, NULL);
+       N = node(I->token, I->label, NULL, NULL, NULL);
 }
 
 %left TOK_PLUS TOK_MINUS.
@@ -67,40 +70,40 @@ node(N) ::= ident(I). {
 %left TOK_NOT.
 
 node(N) ::= node(A) TOK_PLUS node(B). {
-       N = node("+", A, B, NULL);
+       N = node(TOK_PLUS, "+", A, B, NULL);
 }
 
 node(N) ::= node(A) TOK_MINUS node(B). {
-       N = node("-", A, B, NULL);
+       N = node(TOK_MINUS, "-", A, B, NULL);
 }
 
 node(N) ::= node(A) TOK_MULTIPLY node(B). {
-       N = node("*", A, B, NULL);
+       N = node(TOK_MULTIPLY, "*", A, B, NULL);
 }
 
 node(N) ::= node(A) TOK_DIVIDE node(B). {
-       N = node("/", A, B, NULL);
+       N = node(TOK_DIVIDE, "/", A, B, NULL);
 }
 
 node(N) ::= node(A) TOK_PERCENT node(B). {
-       N = node("%", A, B, NULL);
+       N = node(TOK_PERCENT, "%", A, B, NULL);
 }
 
 node(N) ::= TOK_MINUS node(A). [TOK_NOT] {
-       N = node("!", A, NULL, NULL);
+       N = node(TOK_NOT, "!", A, NULL, NULL);
 }
 
 node(N) ::= unary(I) TOK_LPAREN node(A) TOK_RPAREN. {
-       N = node(I, A, NULL, NULL);
+       N = node(I->token, I->label, A, NULL, NULL);
 }
 
 node(N) ::= binary(I) TOK_LPAREN node(A) TOK_COMMA node(B) TOK_RPAREN. {
-       N = node(I, A, B, NULL);
+       N = node(I->token, I->label, A, B, NULL);
 }
 
 node(N) ::= ternary(I) TOK_LPAREN node(A) TOK_COMMA node(B) TOK_COMMA node(C)
     TOK_RPAREN. {
-       N = node(I, A, B, C);
+       N = node(I->token, I->label, A, B, C);
 }
 
 node(N) ::= TOK_LPAREN node(A) TOK_RPAREN. {
diff --git a/software/libfpvm/parser_helper.c b/software/libfpvm/parser_helper.c
index 1b61f45..55694ff 100644
--- a/software/libfpvm/parser_helper.c
+++ b/software/libfpvm/parser_helper.c
@@ -26,7 +26,7 @@ struct ast_node *fpvm_parse(const char *expr)
 {
        struct scanner *s;
        int tok;
-       char *identifier;
+       struct id *identifier;
        void *p;
        struct ast_node *ast;
        
@@ -35,8 +35,10 @@ struct ast_node *fpvm_parse(const char *expr)
        p = ParseAlloc(malloc);
        tok = scan(s);
        while(tok != TOK_EOF) {
-               identifier = malloc(IDENTIFIER_SIZE);
-               get_token(s, (unsigned char *)identifier, IDENTIFIER_SIZE);
+               identifier = malloc(sizeof(struct id));
+               identifier->token = tok;
+               get_token(s, (unsigned char *) identifier->label,
+                   IDENTIFIER_SIZE);
                Parse(p, tok, identifier, &ast);
                if(tok == TOK_ERROR) {
                        printf("FPVM: scan error\n");
-- 
1.7.1

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