nqasm: Handle immediate arguments

2 files changed, 41 insertions, 6 deletions

diff --git a/lexer.l b/lexer.l
index f3a540c..85021c5 100644
--- a/lexer.l
+++ b/lexer.l
@@ -1,9 +1,19 @@
 %{
 
+#include <errno.h>
+#include <stdlib.h>
+
 #include "parser.h"
 
 #define SETVALUE(v) yylval.arg = (struct argument) { .value = (v) }
 
+static int intlit(const char *s, int base, long *out)
+{
+	errno = 0;
+	*out = strtol(s, NULL, base);
+	return errno == ERANGE ? T_BADINT : T_INT;
+}
+
 %}
 
 %option outfile="lexer.c" header-file="lexer.h"
@@ -16,6 +26,8 @@ COMMENT    #[^\n]*
 SP         [ \t]
 EOI        [ \t\n#]
 REGNUM     [0-7]
+DEC        [0-9]
+HEX        [0-9a-f]
 
 %%
 
@@ -59,6 +71,8 @@ REGNUM     [0-7]
 
 <args>r{REGNUM}          { SETVALUE(yytext[1]-'0'); return T_REG;    }
 <args>@r{REGNUM}         { SETVALUE(yytext[2]-'0'); return T_REGPTR; }
+<args>[-+]?{DEC}+        { return intlit(yytext,   10, &yylval.lval); }
+<args>0x{HEX}+           { return intlit(yytext+2, 16, &yylval.lval); }
 <args>{SP}*,{SP}*        { return T_COMMA; }
 
 {SP}*{COMMENT}?\n        { BEGIN(INITIAL); return T_EOL;    }
diff --git a/parser.y b/parser.y
index 2177ae8..c953aa4 100644
--- a/parser.y
+++ b/parser.y
@@ -13,6 +13,7 @@ void yyerror(const char *msg)
 #define INSTRUCTION_ARGS(m,a) (struct instruction) { MNEM_ ## m, a }
 #define INSTRUCTION(m)        (struct instruction) { MNEM_ ## m }
 #define MKARGS(...)           (struct arguments)   { __VA_ARGS__ }
+#define MKARGVALUE(v)         (struct argument)    { (v) }
 
 %}
 
@@ -27,6 +28,7 @@ void yyerror(const char *msg)
 	struct instruction inst;
 	struct arguments   args;
 	struct argument    arg;
+	long               lval;
 }
 
 %token END 0 "end of file"
@@ -70,16 +72,22 @@ void yyerror(const char *msg)
 %token T_ADDPC
 %token T_NOP
 
+%token <lval> T_INT
+%token        T_BADINT
+
 %token <arg> T_REG
 %token <arg> T_REGPTR
 %token       T_COMMA    ","
 
 %type <inst> inst
+%type <arg>  imm
 %type <args> reg2
 %type <args> reg3
 %type <args> regp
 %type <args> regp_reg
 %type <args> reg_regp
+%type <args> reg_imm
+%type <lval> intlit
 
 %%
 
@@ -115,10 +123,8 @@ inst:	T_ADD    reg3      { $$ = INSTRUCTION_ARGS(ADD,    $2); }
 	|	T_LD_BL  reg_regp  { $$ = INSTRUCTION_ARGS(LD_BL,  $2); }
 	|	T_LD_BH  reg_regp  { $$ = INSTRUCTION_ARGS(LD_BH,  $2); }
 	|	T_LD_W   reg_regp  { $$ = INSTRUCTION_ARGS(LD_W,   $2); }
-	|	T_LDI_BL
-		{ $$ = INSTRUCTION(LDI_BL); }
-	|	T_LDI_BH
-		{ $$ = INSTRUCTION(LDI_BH); }
+	|	T_LDI_BL reg_imm   { $$ = INSTRUCTION_ARGS(LDI_BL, $2); }
+	|	T_LDI_BH reg_imm   { $$ = INSTRUCTION_ARGS(LDI_BH, $2); }
 	|	T_BEQ
 		{ $$ = INSTRUCTION(BEQ); }
 	|	T_BNE
@@ -134,8 +140,7 @@ inst:	T_ADD    reg3      { $$ = INSTRUCTION_ARGS(ADD,    $2); }
 	|	T_BRA
 		{ $$ = INSTRUCTION(BRA); }
 	|	T_JMP    regp      { $$ = INSTRUCTION_ARGS(JMP,    $2); }
-	|	T_ADDPC
-		{ $$ = INSTRUCTION(ADDPC); }
+	|	T_ADDPC  reg_imm   { $$ = INSTRUCTION_ARGS(ADDPC,  $2); }
 	|	T_NOP
 		{ $$ = INSTRUCTION(NOP); }
 	;
@@ -145,6 +150,22 @@ reg3:		T_SPACE T_REG "," T_REG "," T_REG    { $$ = MKARGS($2, $4, $6); }
 regp:		T_SPACE T_REGPTR                     { $$ = MKARGS($2);         }
 regp_reg:	T_SPACE T_REGPTR "," T_REG           { $$ = MKARGS($2, $4);     }
 reg_regp:	T_SPACE T_REG "," T_REGPTR           { $$ = MKARGS($2, $4);     }
+reg_imm:	T_SPACE T_REG "," imm                { $$ = MKARGS($2, $4);     }
+
+imm:	intlit {
+			if (-0x80 > $1 || $1 > 0xff) {
+				yyerror("immediate operand out of range");
+				YYERROR;
+			} else {
+				$$ = MKARGVALUE((uint8_t) $1);
+			}
+		}
+
+intlit:	T_INT
+	|	T_BADINT {
+			yyerror("integer literal out of range");
+			YYERROR;
+		}
 
 eol:	T_EOL
 	|	T_SPACE T_EOL