From 633e6598859fc5104bb28d5cccac845cb5d5198e Mon Sep 17 00:00:00 2001
From: Bobby Bingham <koorogi@koorogi.info>
Date: Wed, 18 Jan 2017 20:12:49 -0600
Subject: nqasm: support binary arithmetic operators in immediate operands

---
 lexer.l  |  4 ++++
 nqasm.c  |  5 +++++
 nqasm.h  |  7 ++++++-
 parser.y | 29 +++++++++++++++++++++--------
 4 files changed, 36 insertions(+), 9 deletions(-)

diff --git a/lexer.l b/lexer.l
index 324c3da..9b1548d 100644
--- a/lexer.l
+++ b/lexer.l
@@ -78,8 +78,12 @@ HEX        [0-9a-f]
 <args>@                  { return T_DEREF; }
 <args>\+                 { return T_OPERATOR_ADD; }
 <args>-                  { return T_OPERATOR_SUB; }
+<args>\*                 { return T_OPERATOR_MUL; }
+<args>\/                 { return T_OPERATOR_DIV; }
 <args>!                  { return T_OPERATOR_NOT; }
 <args>~                  { return T_OPERATOR_INV; }
+<args>\(                 { return T_LPAREN; }
+<args>\)                 { return T_RPAREN; }
 <args>{DEC}+             { return intlit(yytext,   10, &yylval.lval); }
 <args>0x{HEX}+           { return intlit(yytext+2, 16, &yylval.lval); }
 <args>{SP}*,{SP}*        { return T_COMMA; }
diff --git a/nqasm.c b/nqasm.c
index 49b4ec6..e915bd7 100644
--- a/nqasm.c
+++ b/nqasm.c
@@ -78,6 +78,11 @@ static long eval_argument(const struct argument *arg, uint16_t pc)
 	case ARG_UNARY_NOT: return !eval_argument(arg->children[0], pc);
 	case ARG_UNARY_INV: return ~eval_argument(arg->children[0], pc);
 
+	case ARG_ADD: return eval_argument(arg->children[0], pc) + eval_argument(arg->children[1], pc);
+	case ARG_SUB: return eval_argument(arg->children[0], pc) - eval_argument(arg->children[1], pc);
+	case ARG_MUL: return eval_argument(arg->children[0], pc) * eval_argument(arg->children[1], pc);
+	case ARG_DIV: return eval_argument(arg->children[0], pc) / eval_argument(arg->children[1], pc);
+
 	case ARG_LABEL:
 		l = vector_search(&labels->v, &(struct label) { .name = arg->label }, cmp_label);
 		if (l) return l->addr;
diff --git a/nqasm.h b/nqasm.h
index e5a7452..3e6ec72 100644
--- a/nqasm.h
+++ b/nqasm.h
@@ -10,6 +10,11 @@ enum {
 	ARG_UNARY_SUB,
 	ARG_UNARY_NOT,
 	ARG_UNARY_INV,
+
+	ARG_ADD,
+	ARG_SUB,
+	ARG_MUL,
+	ARG_DIV,
 };
 
 struct argument {
@@ -17,7 +22,7 @@ struct argument {
 	union {
 		long value;
 		char *label;
-		const struct argument *children[1];
+		const struct argument *children[2];
 	};
 };
 
diff --git a/parser.y b/parser.y
index cb1343f..ed33aa4 100644
--- a/parser.y
+++ b/parser.y
@@ -16,7 +16,7 @@ void yyerror(const char *msg)
 #define MKARGVALUE(v)         (struct argument)    { .type = ARG_INTEGER, .value = (v) }
 #define MKARGLABEL(l)         (struct argument)    { .type = ARG_LABEL,   .label = (l) }
 #define MKARGTYPE(t)          (struct argument)    { .type = (t) }
-#define MKARGEXPR(op,c)       (struct argument)    { .type = (op), .children = c }
+#define MKARGEXPR(op,...)     (struct argument)    { .type = (op), .children = { __VA_ARGS__ } }
 
 %}
 
@@ -87,8 +87,16 @@ void yyerror(const char *msg)
 
 %token       T_OPERATOR_ADD  "+"
 %token       T_OPERATOR_SUB  "-"
+%token       T_OPERATOR_MUL  "*"
+%token       T_OPERATOR_DIV  "/"
 %token       T_OPERATOR_NOT  "!"
 %token       T_OPERATOR_INV  "~"
+%token       T_LPAREN        "("
+%token       T_RPAREN        ")"
+
+%left "-" "+"
+%left "*" "/"
+%precedence NEG
 
 %type <inst> inst
 %type <arg>  reg
@@ -184,13 +192,18 @@ reg:	T_LABEL {
 		}
 
 expr:
-		intlit         { $$ = MKARGVALUE($1); }
-	|	T_LABEL        { $$ = MKARGLABEL($1); }
-	|	"."            { $$ = MKARGTYPE(ARG_PC); }
-	|	"+" expr       { $$ = MKARGEXPR(ARG_UNARY_ADD, { argdup(&$2) }); }
-	|	"-" expr       { $$ = MKARGEXPR(ARG_UNARY_SUB, { argdup(&$2) }); }
-	|	"!" expr       { $$ = MKARGEXPR(ARG_UNARY_NOT, { argdup(&$2) }); }
-	|	"~" expr       { $$ = MKARGEXPR(ARG_UNARY_INV, { argdup(&$2) }); }
+		intlit                 { $$ = MKARGVALUE($1); }
+	|	T_LABEL                { $$ = MKARGLABEL($1); }
+	|	"."                    { $$ = MKARGTYPE(ARG_PC); }
+	|	"+" expr     %prec NEG { $$ = MKARGEXPR(ARG_UNARY_ADD, argdup(&$2)); }
+	|	"-" expr     %prec NEG { $$ = MKARGEXPR(ARG_UNARY_SUB, argdup(&$2)); }
+	|	"!" expr     %prec NEG { $$ = MKARGEXPR(ARG_UNARY_NOT, argdup(&$2)); }
+	|	"~" expr     %prec NEG { $$ = MKARGEXPR(ARG_UNARY_INV, argdup(&$2)); }
+	|	expr "+" expr          { $$ = MKARGEXPR(ARG_ADD, argdup(&$1), argdup(&$3)); }
+	|	expr "-" expr          { $$ = MKARGEXPR(ARG_SUB, argdup(&$1), argdup(&$3)); }
+	|	expr "*" expr          { $$ = MKARGEXPR(ARG_MUL, argdup(&$1), argdup(&$3)); }
+	|	expr "/" expr          { $$ = MKARGEXPR(ARG_DIV, argdup(&$1), argdup(&$3)); }
+	|	"(" expr ")"           { $$ = $2; }
 	;
 
 intlit:	T_INT
-- 
cgit v1.2.3