diff options
| -rw-r--r-- | src/sys/include/np/lex.h | 2 | ||||
| -rw-r--r-- | src/sys/include/np/piir.h | 1 | ||||
| -rw-r--r-- | src/sys/np/core/np_lex.c | 5 | ||||
| -rw-r--r-- | src/sys/np/core/np_parse.c | 37 |
4 files changed, 44 insertions, 1 deletions
diff --git a/src/sys/include/np/lex.h b/src/sys/include/np/lex.h index ebd6f32..ba581b7 100644 --- a/src/sys/include/np/lex.h +++ b/src/sys/include/np/lex.h @@ -41,6 +41,7 @@ struct np_work; #define TOKEN_BEGIN "begin" #define TOKEN_PROC "proc" #define TOKEN_END "end" +#define TOKEN_RETURN "return" /* Types */ #define TOKEN_U8 "u8" @@ -93,6 +94,7 @@ typedef enum { TT_BEGIN, /* 'begin' */ TT_PROC, /* 'proc' */ TT_END, /* 'end' */ + TT_RETURN, /* 'return' */ } tt_t; typedef uint64_t tokval_t; diff --git a/src/sys/include/np/piir.h b/src/sys/include/np/piir.h index d108776..5625409 100644 --- a/src/sys/include/np/piir.h +++ b/src/sys/include/np/piir.h @@ -56,6 +56,7 @@ typedef int8_t md_byte_t; #define PIIR_LOAD_R32 0x03 /* Load 32-bit register */ #define PIIR_LOAD_R64 0x04 /* Load 64-bit register */ #define PIIR_RET_NIL 0x05 /* Return nothing */ +#define PIIR_RET_NUM 0x06 /* Return a number */ /* * Represents the PIIR virtual machine for storing diff --git a/src/sys/np/core/np_lex.c b/src/sys/np/core/np_lex.c index 389f1e2..222feba 100644 --- a/src/sys/np/core/np_lex.c +++ b/src/sys/np/core/np_lex.c @@ -144,6 +144,11 @@ static int lex_cmptok(char *tokstr, struct lex_token *res) { switch (*tokstr) { + case 'r': + if (strcmp(tokstr, TOKEN_RETURN) == 0) { + res->token = TT_RETURN; + } + return 0; case 'b': if (strcmp(tokstr, TOKEN_BEGIN) == 0) { res->token = TT_BEGIN; diff --git a/src/sys/np/core/np_parse.c b/src/sys/np/core/np_parse.c index 4119d8b..b7b854b 100644 --- a/src/sys/np/core/np_parse.c +++ b/src/sys/np/core/np_parse.c @@ -84,7 +84,8 @@ static const char *stoktab[] = { /* Keywords */ [TT_BEGIN] = "<TT_BEGIN>", [TT_PROC] = "<TT_PROC>", - [TT_END] = "<TT_END>" + [TT_END] = "<TT_END>", + [TT_RETURN] = "<TT_RETURN>" }; /* @@ -173,6 +174,35 @@ parse_type(struct np_work *work, struct lex_token *tok) } /* + * Parse a return statement + * + * @work: Input work + * @tok: Current token + * + * Returns zero on success + */ +static int +parse_return(struct np_work *work, struct lex_token *tok) +{ + tt_t tt; + + /* + * For now we'll only accept numbers as return values + * so we must see one after the return statement + */ + tt = parse_expect(work, "return", TT_NUMBER, tok); + if (tt == TT_NONE) { + return -1; + } + +#define PIIR_PUSH(BYTE) piir_push(work->piir_stack, (BYTE)) + PIIR_PUSH(PIIR_RET_NUM); + PIIR_PUSH(tok->val); +#undef PIIR_PUSH + return 0; +} + +/* * Parse a procedure / function * * @work: Input work @@ -311,6 +341,11 @@ parse_token(struct np_work *work, struct lex_token *tok) /* XXX: NOP for testing */ PIIR_PUSH(PIIR_NOP); break; + case TT_RETURN: + if ((error = parse_return(work, tok)) != 0) { + return -1; + } + break; } #undef PIIR_PUSH return 0; |