nqasm: Initial stab at a lexer and parser

So far, this only understands instructions, but no operands or labels.  It
doesn't handle bad input gracefully.  It's just enough to test the basics.

1 files changed, 61 insertions, 0 deletions

diff --git a/lexer.l b/lexer.l
new file mode 100644
index 0000000..9a34d66
--- /dev/null
+++ b/lexer.l
@@ -0,0 +1,61 @@
+%{
+
+#include "parser.h"
+
+%}
+
+%option outfile="lexer.c" header-file="lexer.h"
+%option noyywrap never-interactive
+
+%s inst
+%s args
+
+COMMENT    #[^\n]*
+SP         [ \t]
+EOI        [ \t\n#]
+
+%%
+
+<INITIAL>{SP}+           { BEGIN(inst);    return T_SPACE; }
+
+<inst>add/{EOI}          { BEGIN(args);    return T_ADD;    }
+<inst>sub/{EOI}          { BEGIN(args);    return T_SUB;    }
+<inst>mul/{EOI}          { BEGIN(args);    return T_MUL;    }
+<inst>div/{EOI}          { BEGIN(args);    return T_DIV;    }
+<inst>and/{EOI}          { BEGIN(args);    return T_AND;    }
+<inst>or/{EOI}           { BEGIN(args);    return T_OR;     }
+<inst>xor/{EOI}          { BEGIN(args);    return T_XOR;    }
+<inst>lsl/{EOI}          { BEGIN(args);    return T_LSL;    }
+<inst>lsr/{EOI}          { BEGIN(args);    return T_LSR;    }
+<inst>asl/{EOI}          { BEGIN(args);    return T_ASL;    }
+<inst>asr/{EOI}          { BEGIN(args);    return T_ASR;    }
+<inst>rol/{EOI}          { BEGIN(args);    return T_ROL;    }
+<inst>ror/{EOI}          { BEGIN(args);    return T_ROR;    }
+<inst>not/{EOI}          { BEGIN(args);    return T_NOT;    }
+<inst>neg/{EOI}          { BEGIN(args);    return T_NEG;    }
+<inst>btc/{EOI}          { BEGIN(args);    return T_BTC;    }
+<inst>bts/{EOI}          { BEGIN(args);    return T_BTS;    }
+<inst>mov/{EOI}          { BEGIN(args);    return T_MOV;    }
+<inst>st\.b/{EOI}        { BEGIN(args);    return T_ST_B;   }
+<inst>st\.w/{EOI}        { BEGIN(args);    return T_ST_W;   }
+<inst>ld\.bl/{EOI}       { BEGIN(args);    return T_LD_BL;  }
+<inst>ld\.bh/{EOI}       { BEGIN(args);    return T_LD_BH;  }
+<inst>ld\.w/{EOI}        { BEGIN(args);    return T_LD_W;   }
+<inst>ldi\.bl/{EOI}      { BEGIN(args);    return T_LDI_BL; }
+<inst>ldi\.bh/{EOI}      { BEGIN(args);    return T_LDI_BH; }
+<inst>beq/{EOI}          { BEGIN(args);    return T_BEQ;    }
+<inst>bne/{EOI}          { BEGIN(args);    return T_BNE;    }
+<inst>bgt/{EOI}          { BEGIN(args);    return T_BGT;    }
+<inst>bge/{EOI}          { BEGIN(args);    return T_BGE;    }
+<inst>blt/{EOI}          { BEGIN(args);    return T_BLT;    }
+<inst>ble/{EOI}          { BEGIN(args);    return T_BLE;    }
+<inst>bra/{EOI}          { BEGIN(args);    return T_BRA;    }
+<inst>jmp/{EOI}          { BEGIN(args);    return T_JMP;    }
+<inst>addpc/{EOI}        { BEGIN(args);    return T_ADDPC;  }
+<inst>nop/{EOI}          { BEGIN(args);    return T_NOP;    }
+
+{SP}*{COMMENT}?\n        { BEGIN(INITIAL); return T_EOL;    }
+{SP}*{COMMENT}           { BEGIN(INITIAL); return T_SPACE;  }
+{SP}+                    {                 return T_SPACE;  }
+
+%%