From: Michael Urman <mu@tortall.net>
Date: Thu, 5 Jul 2001 08:37:59 +0000 (-0000)
Subject: Long hairy integration of expression handling into the grammar.
X-Git-Tag: v0.1.0~402
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=84bae30656182c2734bb5dd632a9109b82a553c5;p=yasm

Long hairy integration of expression handling into the grammar.
Added printing, getvalue functionality to expr.[ch]
Changed immval to house an expr* instead of an unsigned long.

gen_instr.pl needs to be updated for ONE cases to fix pointer compares.
bison s/r conflicts still need to be handled.

svn path=/trunk/yasm/; revision=109
---

diff --git a/include/bytecode.h b/include/bytecode.h
index d17ec0a6..ce8ee6bd 100644
--- a/include/bytecode.h
+++ b/include/bytecode.h
@@ -1,4 +1,4 @@
-/* $Id: bytecode.h,v 1.8 2001/06/28 21:22:01 peter Exp $
+/* $Id: bytecode.h,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Bytecode utility functions header file
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -38,7 +38,7 @@ typedef struct effaddr_s {
 } effaddr;
 
 typedef struct immval_s {
-    unsigned long val;
+    struct expr_s *val;
 
     unsigned char len;		/* length of val (in bytes), 0 if none */
     unsigned char isrel;
diff --git a/include/expr.h b/include/expr.h
index 18d6eee1..3ca1ec68 100644
--- a/include/expr.h
+++ b/include/expr.h
@@ -1,4 +1,4 @@
-/* $Id: expr.h,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.h,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling header file
  *
  *  Copyright (C) 2001  Michael Urman
@@ -57,7 +57,7 @@ typedef enum {
 typedef union expritem_u {
     struct symrec_s *sym;
     struct expr_s *expr;
-    int num;
+    unsigned long num;
 } ExprItem;
 
 typedef struct expr_s {
@@ -67,6 +67,20 @@ typedef struct expr_s {
 } expr;
 
 expr *expr_new (ExprType, ExprItem, ExprOp, ExprType, ExprItem);
+/*expr *expr_new_tree (ExprItem, ExprOp, ExprItem);
+expr *expr_new_branch (ExprOp, ExprItem);
+expr *expr_new_ident (ExprType, ExprItem);*/
+#define expr_new_tree(l,o,r) \
+    expr_new (EXPR_EXPR, (ExprItem)(l), (ExprOp)(o), EXPR_EXPR, (ExprItem)(r))
+#define expr_new_branch(o,r) \
+    expr_new (EXPR_NONE, (ExprItem)0UL, (ExprOp)(o), EXPR_EXPR, (ExprItem)(r))
+#define expr_new_ident(t,r) \
+    expr_new (EXPR_NONE, (ExprItem)0UL, EXPR_IDENT, (ExprType)(t), (ExprItem)(r))
 int expr_simplify (expr *);
 
+void expr_print (expr *);
+
+/* get the value if possible.  return value is IF POSSIBLE, not the val */
+int expr_get_value (expr *, unsigned long *);
+
 #endif
diff --git a/libyasm/bytecode.c b/libyasm/bytecode.c
index f9d92a01..5812dbd2 100644
--- a/libyasm/bytecode.c
+++ b/libyasm/bytecode.c
@@ -1,4 +1,4 @@
-/* $Id: bytecode.c,v 1.8 2001/05/30 07:41:03 peter Exp $
+/* $Id: bytecode.c,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Bytecode utility functions
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -23,6 +23,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 static effaddr eff_static;
 static immval im_static;
@@ -70,10 +71,12 @@ effaddr *ConvertRegToEA(effaddr *ptr, unsigned long reg)
 
 effaddr *ConvertImmToEA(effaddr *ptr, immval *im_ptr, unsigned char im_len)
 {
+    int gotexprval;
     if(!ptr)
 	ptr = &eff_static;
 
-    ptr->disp = im_ptr->val;
+    /* FIXME: warn when gotexprval is 0, and/or die */
+    gotexprval = expr_get_value (im_ptr->val, &ptr->disp);
     if(im_ptr->len > im_len)
 	Warning(WARN_VALUE_EXCEEDS_BOUNDS, (char *)NULL, "word");
     ptr->len = im_len;
@@ -91,7 +94,8 @@ immval *ConvertIntToImm(immval *ptr, unsigned long int_val)
     if(!ptr)
 	ptr = &im_static;
 
-    ptr->val = int_val;
+    /* FIXME: this will leak expr's if static is used */
+    ptr->val = expr_new_ident(EXPR_NUM, int_val);
 
     if((int_val & 0xFF) == int_val)
 	ptr->len = 1;
@@ -106,6 +110,19 @@ immval *ConvertIntToImm(immval *ptr, unsigned long int_val)
     return ptr;
 }
 
+immval *ConvertExprToImm(immval *ptr, expr *expr_ptr)
+{
+    if(!ptr)
+	ptr = &im_static;
+
+    ptr->val = expr_ptr;
+
+    ptr->isrel = 0;
+    ptr->isneg = 0;
+
+    return ptr;
+}
+
 void SetEASegment(effaddr *ptr, unsigned char segment)
 {
     if(!ptr)
@@ -240,7 +257,9 @@ void DebugPrintBC(bytecode *bc)
 		(unsigned int)bc->data.insn.ea.valid_sib,
 		(unsigned int)bc->data.insn.ea.need_sib);
 	    printf("Immediate/Relative Value:\n");
-	    printf(" Val=%lx\n", bc->data.insn.imm.val);
+	    printf(" Val=");
+	    expr_print(bc->data.insn.imm.val);
+	    printf("\n");
 	    printf(" Len=%u, IsRel=%u, IsNeg=%u\n",
 		(unsigned int)bc->data.insn.imm.len,
 		(unsigned int)bc->data.insn.imm.isrel,
diff --git a/libyasm/bytecode.h b/libyasm/bytecode.h
index d17ec0a6..ce8ee6bd 100644
--- a/libyasm/bytecode.h
+++ b/libyasm/bytecode.h
@@ -1,4 +1,4 @@
-/* $Id: bytecode.h,v 1.8 2001/06/28 21:22:01 peter Exp $
+/* $Id: bytecode.h,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Bytecode utility functions header file
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -38,7 +38,7 @@ typedef struct effaddr_s {
 } effaddr;
 
 typedef struct immval_s {
-    unsigned long val;
+    struct expr_s *val;
 
     unsigned char len;		/* length of val (in bytes), 0 if none */
     unsigned char isrel;
diff --git a/libyasm/expr.c b/libyasm/expr.c
index e6210957..0d7f7221 100644
--- a/libyasm/expr.c
+++ b/libyasm/expr.c
@@ -1,4 +1,4 @@
-/* $Id: expr.c,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.c,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling
  *
  *  Copyright (C) 2001  Michael Urman
@@ -189,3 +189,58 @@ int expr_simplify (expr *e)
 
     return simplified;
 }
+
+int expr_get_value (expr *e, unsigned long *retval)
+{
+    while (!(e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+	   && expr_simplify (e));
+
+    if (e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+    {
+	*retval = e->right.num;
+	return 1;
+    }
+    else
+	return 0;
+}
+
+void expr_print (expr *e)
+{
+    if (e->op != EXPR_IDENT) {
+	switch (e->ltype) {
+	    case EXPR_NUM: printf ("%d", e->left.num); break;
+	    case EXPR_SYM: printf ("%s", e->left.sym->name); break;
+	    case EXPR_EXPR: printf ("("); expr_print (e->left.expr); printf(")");
+	    case EXPR_NONE: break;
+	}
+    }
+    switch (e->op) {
+	case EXPR_ADD: printf ("+"); break;
+	case EXPR_SUB: printf ("-"); break;
+	case EXPR_MUL: printf ("*"); break;
+	case EXPR_DIV: printf ("/"); break;
+	case EXPR_MOD: printf ("%"); break;
+	case EXPR_NEG: printf ("-"); break;
+	case EXPR_NOT: printf ("~"); break;
+	case EXPR_OR: printf ("|"); break;
+	case EXPR_AND: printf ("&"); break;
+	case EXPR_XOR: printf ("^"); break;
+	case EXPR_SHL: printf ("<<"); break;
+	case EXPR_SHR: printf (">>"); break;
+	case EXPR_LOR: printf ("||"); break;
+	case EXPR_LAND: printf ("&&"); break;
+	case EXPR_LNOT: printf ("!"); break;
+	case EXPR_LT: printf ("<"); break;
+	case EXPR_GT: printf (">"); break;
+	case EXPR_LE: printf ("<="); break;
+	case EXPR_GE: printf (">="); break;
+	case EXPR_NE: printf ("!="); break;
+	case EXPR_IDENT: break;
+    }
+    switch (e->rtype) {
+	case EXPR_NUM: printf ("%d", e->right.num); break;
+	case EXPR_SYM: printf ("%s", e->right.sym->name); break;
+	case EXPR_EXPR: printf ("("); expr_print (e->right.expr); printf(")");
+	case EXPR_NONE: break;
+    }
+}
diff --git a/libyasm/expr.h b/libyasm/expr.h
index 18d6eee1..3ca1ec68 100644
--- a/libyasm/expr.h
+++ b/libyasm/expr.h
@@ -1,4 +1,4 @@
-/* $Id: expr.h,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.h,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling header file
  *
  *  Copyright (C) 2001  Michael Urman
@@ -57,7 +57,7 @@ typedef enum {
 typedef union expritem_u {
     struct symrec_s *sym;
     struct expr_s *expr;
-    int num;
+    unsigned long num;
 } ExprItem;
 
 typedef struct expr_s {
@@ -67,6 +67,20 @@ typedef struct expr_s {
 } expr;
 
 expr *expr_new (ExprType, ExprItem, ExprOp, ExprType, ExprItem);
+/*expr *expr_new_tree (ExprItem, ExprOp, ExprItem);
+expr *expr_new_branch (ExprOp, ExprItem);
+expr *expr_new_ident (ExprType, ExprItem);*/
+#define expr_new_tree(l,o,r) \
+    expr_new (EXPR_EXPR, (ExprItem)(l), (ExprOp)(o), EXPR_EXPR, (ExprItem)(r))
+#define expr_new_branch(o,r) \
+    expr_new (EXPR_NONE, (ExprItem)0UL, (ExprOp)(o), EXPR_EXPR, (ExprItem)(r))
+#define expr_new_ident(t,r) \
+    expr_new (EXPR_NONE, (ExprItem)0UL, EXPR_IDENT, (ExprType)(t), (ExprItem)(r))
 int expr_simplify (expr *);
 
+void expr_print (expr *);
+
+/* get the value if possible.  return value is IF POSSIBLE, not the val */
+int expr_get_value (expr *, unsigned long *);
+
 #endif
diff --git a/modules/arch/x86/expr.c b/modules/arch/x86/expr.c
index e6210957..0d7f7221 100644
--- a/modules/arch/x86/expr.c
+++ b/modules/arch/x86/expr.c
@@ -1,4 +1,4 @@
-/* $Id: expr.c,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.c,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling
  *
  *  Copyright (C) 2001  Michael Urman
@@ -189,3 +189,58 @@ int expr_simplify (expr *e)
 
     return simplified;
 }
+
+int expr_get_value (expr *e, unsigned long *retval)
+{
+    while (!(e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+	   && expr_simplify (e));
+
+    if (e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+    {
+	*retval = e->right.num;
+	return 1;
+    }
+    else
+	return 0;
+}
+
+void expr_print (expr *e)
+{
+    if (e->op != EXPR_IDENT) {
+	switch (e->ltype) {
+	    case EXPR_NUM: printf ("%d", e->left.num); break;
+	    case EXPR_SYM: printf ("%s", e->left.sym->name); break;
+	    case EXPR_EXPR: printf ("("); expr_print (e->left.expr); printf(")");
+	    case EXPR_NONE: break;
+	}
+    }
+    switch (e->op) {
+	case EXPR_ADD: printf ("+"); break;
+	case EXPR_SUB: printf ("-"); break;
+	case EXPR_MUL: printf ("*"); break;
+	case EXPR_DIV: printf ("/"); break;
+	case EXPR_MOD: printf ("%"); break;
+	case EXPR_NEG: printf ("-"); break;
+	case EXPR_NOT: printf ("~"); break;
+	case EXPR_OR: printf ("|"); break;
+	case EXPR_AND: printf ("&"); break;
+	case EXPR_XOR: printf ("^"); break;
+	case EXPR_SHL: printf ("<<"); break;
+	case EXPR_SHR: printf (">>"); break;
+	case EXPR_LOR: printf ("||"); break;
+	case EXPR_LAND: printf ("&&"); break;
+	case EXPR_LNOT: printf ("!"); break;
+	case EXPR_LT: printf ("<"); break;
+	case EXPR_GT: printf (">"); break;
+	case EXPR_LE: printf ("<="); break;
+	case EXPR_GE: printf (">="); break;
+	case EXPR_NE: printf ("!="); break;
+	case EXPR_IDENT: break;
+    }
+    switch (e->rtype) {
+	case EXPR_NUM: printf ("%d", e->right.num); break;
+	case EXPR_SYM: printf ("%s", e->right.sym->name); break;
+	case EXPR_EXPR: printf ("("); expr_print (e->right.expr); printf(")");
+	case EXPR_NONE: break;
+    }
+}
diff --git a/modules/arch/x86/x86expr.c b/modules/arch/x86/x86expr.c
index f653822a..1bf3c884 100644
--- a/modules/arch/x86/x86expr.c
+++ b/modules/arch/x86/x86expr.c
@@ -1,4 +1,4 @@
-/* $Id: x86expr.c,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: x86expr.c,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling
  *
  *  Copyright (C) 2001  Michael Urman
@@ -189,3 +189,58 @@ int expr_simplify (expr *e)
 
     return simplified;
 }
+
+int expr_get_value (expr *e, unsigned long *retval)
+{
+    while (!(e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+	   && expr_simplify (e));
+
+    if (e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+    {
+	*retval = e->right.num;
+	return 1;
+    }
+    else
+	return 0;
+}
+
+void expr_print (expr *e)
+{
+    if (e->op != EXPR_IDENT) {
+	switch (e->ltype) {
+	    case EXPR_NUM: printf ("%d", e->left.num); break;
+	    case EXPR_SYM: printf ("%s", e->left.sym->name); break;
+	    case EXPR_EXPR: printf ("("); expr_print (e->left.expr); printf(")");
+	    case EXPR_NONE: break;
+	}
+    }
+    switch (e->op) {
+	case EXPR_ADD: printf ("+"); break;
+	case EXPR_SUB: printf ("-"); break;
+	case EXPR_MUL: printf ("*"); break;
+	case EXPR_DIV: printf ("/"); break;
+	case EXPR_MOD: printf ("%"); break;
+	case EXPR_NEG: printf ("-"); break;
+	case EXPR_NOT: printf ("~"); break;
+	case EXPR_OR: printf ("|"); break;
+	case EXPR_AND: printf ("&"); break;
+	case EXPR_XOR: printf ("^"); break;
+	case EXPR_SHL: printf ("<<"); break;
+	case EXPR_SHR: printf (">>"); break;
+	case EXPR_LOR: printf ("||"); break;
+	case EXPR_LAND: printf ("&&"); break;
+	case EXPR_LNOT: printf ("!"); break;
+	case EXPR_LT: printf ("<"); break;
+	case EXPR_GT: printf (">"); break;
+	case EXPR_LE: printf ("<="); break;
+	case EXPR_GE: printf (">="); break;
+	case EXPR_NE: printf ("!="); break;
+	case EXPR_IDENT: break;
+    }
+    switch (e->rtype) {
+	case EXPR_NUM: printf ("%d", e->right.num); break;
+	case EXPR_SYM: printf ("%s", e->right.sym->name); break;
+	case EXPR_EXPR: printf ("("); expr_print (e->right.expr); printf(")");
+	case EXPR_NONE: break;
+    }
+}
diff --git a/modules/parsers/nasm/bison.y.in b/modules/parsers/nasm/bison.y.in
index 72b0b96d..f1644f07 100644
--- a/modules/parsers/nasm/bison.y.in
+++ b/modules/parsers/nasm/bison.y.in
@@ -1,4 +1,4 @@
-/* $Id: bison.y.in,v 1.15 2001/07/05 07:21:35 peter Exp $
+/* $Id: bison.y.in,v 1.16 2001/07/05 08:37:59 mu Exp $
  * Main bison parser
  *
  *  Copyright (C) 2001  Peter Johnson, Michael Urman
@@ -26,6 +26,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 #define YYDEBUG 1
 
@@ -46,6 +47,7 @@ extern void yyerror(char *);
     } syminfo;
     unsigned char groupdata[3];
     effaddr ea_val;
+    expr *exp;
     immval im_val;
     bytecode bc;
 } 
@@ -83,7 +85,9 @@ extern void yyerror(char *);
 %type <ea_val> mem8 mem16 mem32 mem64 mem80 mem128 mem1632
 %type <ea_val> rm8x rm16x rm32x /*rm64x rm128x*/
 %type <ea_val> rm8 rm16 rm32 rm64 rm128
-%type <im_val> immexp imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <im_val> imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <exp> immexp
+%type <syminfo> immlabel
 %type <sym> label_id
 
 %left '-' '+'
@@ -271,10 +275,36 @@ rm128: XMMREG	{ (void)ConvertRegToEA(&$$, $1); }
 
 /* immediate values */
 /* TODO: formula expansion */
-immexp: INTNUM	{ (void)ConvertIntToImm(&$$, $1); }
-;
-
-imm: immexp
+immexp: /*INTNUM	{ (void)ConvertIntToImm(&$$, $1); } */
+	INTNUM		{ $$ = expr_new_ident (EXPR_NUM, $1); }
+    | immlabel		{ $$ = expr_new_ident (EXPR_SYM, sym_use_get ($1.name, SYM_LABEL)); }
+    /*| immexp '||' immexp	{ $$ = expr_new_tree ($1, EXPR_LOR, $3); }*/
+    | immexp '|' immexp	{ $$ = expr_new_tree ($1, EXPR_OR, $3); }
+    | immexp '^' immexp	{ $$ = expr_new_tree ($1, EXPR_XOR, $3); }
+    /*| immexp '&&' immexp	{ $$ = expr_new_tree ($1, EXPR_LAND, $3); }*/
+    | immexp '&' immexp	{ $$ = expr_new_tree ($1, EXPR_AND, $3); }
+    /*| immexp '==' immexp	{ $$ = expr_new_tree ($1, EXPR_EQUALS, $3); }*/
+    /*| immexp '>' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '<' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '>=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '<=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '!=' immexp	{ $$ = expr_new_tree ($1, EXPR_NE, $3); }*/
+    | immexp LEFT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHL, $3); }
+    | immexp RIGHT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHR, $3); }
+    | immexp '+' immexp	{ $$ = expr_new_tree ($1, EXPR_ADD, $3); }
+    | immexp '-' immexp	{ $$ = expr_new_tree ($1, EXPR_SUB, $3); }
+    | immexp '*' immexp	{ $$ = expr_new_tree ($1, EXPR_MUL, $3); }
+    | immexp '/' immexp	{ $$ = expr_new_tree ($1, EXPR_DIV, $3); }
+    | immexp '%' immexp	{ $$ = expr_new_tree ($1, EXPR_MOD, $3); }
+    | '-' immexp	{ $$ = expr_new_branch (EXPR_NEG, $2); }
+    /*| '!' immexp	{ $$ = expr_new_branch (EXPR_LNOT, $2); }*/
+    | '~' immexp	{ $$ = expr_new_branch (EXPR_NOT, $2); }
+    | '(' immexp ')'	{ $$ = $2; }
+;
+
+immlabel: ID | SPECIAL_ID | LOCAL_ID ;
+
+imm: immexp		{ expr_simplify ($1); ConvertExprToImm (&$$, $1); }
 ;
 
 /* explicit immediates */
diff --git a/modules/parsers/nasm/nasm-bison.y b/modules/parsers/nasm/nasm-bison.y
index 7a32a80e..6c1a66bb 100644
--- a/modules/parsers/nasm/nasm-bison.y
+++ b/modules/parsers/nasm/nasm-bison.y
@@ -1,4 +1,4 @@
-/* $Id: nasm-bison.y,v 1.15 2001/07/05 07:21:35 peter Exp $
+/* $Id: nasm-bison.y,v 1.16 2001/07/05 08:37:59 mu Exp $
  * Main bison parser
  *
  *  Copyright (C) 2001  Peter Johnson, Michael Urman
@@ -26,6 +26,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 #define YYDEBUG 1
 
@@ -46,6 +47,7 @@ extern void yyerror(char *);
     } syminfo;
     unsigned char groupdata[3];
     effaddr ea_val;
+    expr *exp;
     immval im_val;
     bytecode bc;
 } 
@@ -83,7 +85,9 @@ extern void yyerror(char *);
 %type <ea_val> mem8 mem16 mem32 mem64 mem80 mem128 mem1632
 %type <ea_val> rm8x rm16x rm32x /*rm64x rm128x*/
 %type <ea_val> rm8 rm16 rm32 rm64 rm128
-%type <im_val> immexp imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <im_val> imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <exp> immexp
+%type <syminfo> immlabel
 %type <sym> label_id
 
 %left '-' '+'
@@ -271,10 +275,36 @@ rm128: XMMREG	{ (void)ConvertRegToEA(&$$, $1); }
 
 /* immediate values */
 /* TODO: formula expansion */
-immexp: INTNUM	{ (void)ConvertIntToImm(&$$, $1); }
-;
-
-imm: immexp
+immexp: /*INTNUM	{ (void)ConvertIntToImm(&$$, $1); } */
+	INTNUM		{ $$ = expr_new_ident (EXPR_NUM, $1); }
+    | immlabel		{ $$ = expr_new_ident (EXPR_SYM, sym_use_get ($1.name, SYM_LABEL)); }
+    /*| immexp '||' immexp	{ $$ = expr_new_tree ($1, EXPR_LOR, $3); }*/
+    | immexp '|' immexp	{ $$ = expr_new_tree ($1, EXPR_OR, $3); }
+    | immexp '^' immexp	{ $$ = expr_new_tree ($1, EXPR_XOR, $3); }
+    /*| immexp '&&' immexp	{ $$ = expr_new_tree ($1, EXPR_LAND, $3); }*/
+    | immexp '&' immexp	{ $$ = expr_new_tree ($1, EXPR_AND, $3); }
+    /*| immexp '==' immexp	{ $$ = expr_new_tree ($1, EXPR_EQUALS, $3); }*/
+    /*| immexp '>' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '<' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '>=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '<=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '!=' immexp	{ $$ = expr_new_tree ($1, EXPR_NE, $3); }*/
+    | immexp LEFT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHL, $3); }
+    | immexp RIGHT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHR, $3); }
+    | immexp '+' immexp	{ $$ = expr_new_tree ($1, EXPR_ADD, $3); }
+    | immexp '-' immexp	{ $$ = expr_new_tree ($1, EXPR_SUB, $3); }
+    | immexp '*' immexp	{ $$ = expr_new_tree ($1, EXPR_MUL, $3); }
+    | immexp '/' immexp	{ $$ = expr_new_tree ($1, EXPR_DIV, $3); }
+    | immexp '%' immexp	{ $$ = expr_new_tree ($1, EXPR_MOD, $3); }
+    | '-' immexp	{ $$ = expr_new_branch (EXPR_NEG, $2); }
+    /*| '!' immexp	{ $$ = expr_new_branch (EXPR_LNOT, $2); }*/
+    | '~' immexp	{ $$ = expr_new_branch (EXPR_NOT, $2); }
+    | '(' immexp ')'	{ $$ = $2; }
+;
+
+immlabel: ID | SPECIAL_ID | LOCAL_ID ;
+
+imm: immexp		{ expr_simplify ($1); ConvertExprToImm (&$$, $1); }
 ;
 
 /* explicit immediates */
diff --git a/modules/parsers/nasm/token.l.in b/modules/parsers/nasm/token.l.in
index 4aa92c49..2a19cdc8 100644
--- a/modules/parsers/nasm/token.l.in
+++ b/modules/parsers/nasm/token.l.in
@@ -1,4 +1,4 @@
-/* $Id: token.l.in,v 1.8 2001/06/29 05:11:40 peter Exp $
+/* $Id: token.l.in,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Main lexer
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -34,6 +34,7 @@
 #include "symrec.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 #include "bison.h"
 
 %}
diff --git a/src/arch/x86/expr.c b/src/arch/x86/expr.c
index e6210957..0d7f7221 100644
--- a/src/arch/x86/expr.c
+++ b/src/arch/x86/expr.c
@@ -1,4 +1,4 @@
-/* $Id: expr.c,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.c,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling
  *
  *  Copyright (C) 2001  Michael Urman
@@ -189,3 +189,58 @@ int expr_simplify (expr *e)
 
     return simplified;
 }
+
+int expr_get_value (expr *e, unsigned long *retval)
+{
+    while (!(e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+	   && expr_simplify (e));
+
+    if (e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+    {
+	*retval = e->right.num;
+	return 1;
+    }
+    else
+	return 0;
+}
+
+void expr_print (expr *e)
+{
+    if (e->op != EXPR_IDENT) {
+	switch (e->ltype) {
+	    case EXPR_NUM: printf ("%d", e->left.num); break;
+	    case EXPR_SYM: printf ("%s", e->left.sym->name); break;
+	    case EXPR_EXPR: printf ("("); expr_print (e->left.expr); printf(")");
+	    case EXPR_NONE: break;
+	}
+    }
+    switch (e->op) {
+	case EXPR_ADD: printf ("+"); break;
+	case EXPR_SUB: printf ("-"); break;
+	case EXPR_MUL: printf ("*"); break;
+	case EXPR_DIV: printf ("/"); break;
+	case EXPR_MOD: printf ("%"); break;
+	case EXPR_NEG: printf ("-"); break;
+	case EXPR_NOT: printf ("~"); break;
+	case EXPR_OR: printf ("|"); break;
+	case EXPR_AND: printf ("&"); break;
+	case EXPR_XOR: printf ("^"); break;
+	case EXPR_SHL: printf ("<<"); break;
+	case EXPR_SHR: printf (">>"); break;
+	case EXPR_LOR: printf ("||"); break;
+	case EXPR_LAND: printf ("&&"); break;
+	case EXPR_LNOT: printf ("!"); break;
+	case EXPR_LT: printf ("<"); break;
+	case EXPR_GT: printf (">"); break;
+	case EXPR_LE: printf ("<="); break;
+	case EXPR_GE: printf (">="); break;
+	case EXPR_NE: printf ("!="); break;
+	case EXPR_IDENT: break;
+    }
+    switch (e->rtype) {
+	case EXPR_NUM: printf ("%d", e->right.num); break;
+	case EXPR_SYM: printf ("%s", e->right.sym->name); break;
+	case EXPR_EXPR: printf ("("); expr_print (e->right.expr); printf(")");
+	case EXPR_NONE: break;
+    }
+}
diff --git a/src/arch/x86/x86expr.c b/src/arch/x86/x86expr.c
index f653822a..1bf3c884 100644
--- a/src/arch/x86/x86expr.c
+++ b/src/arch/x86/x86expr.c
@@ -1,4 +1,4 @@
-/* $Id: x86expr.c,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: x86expr.c,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling
  *
  *  Copyright (C) 2001  Michael Urman
@@ -189,3 +189,58 @@ int expr_simplify (expr *e)
 
     return simplified;
 }
+
+int expr_get_value (expr *e, unsigned long *retval)
+{
+    while (!(e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+	   && expr_simplify (e));
+
+    if (e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+    {
+	*retval = e->right.num;
+	return 1;
+    }
+    else
+	return 0;
+}
+
+void expr_print (expr *e)
+{
+    if (e->op != EXPR_IDENT) {
+	switch (e->ltype) {
+	    case EXPR_NUM: printf ("%d", e->left.num); break;
+	    case EXPR_SYM: printf ("%s", e->left.sym->name); break;
+	    case EXPR_EXPR: printf ("("); expr_print (e->left.expr); printf(")");
+	    case EXPR_NONE: break;
+	}
+    }
+    switch (e->op) {
+	case EXPR_ADD: printf ("+"); break;
+	case EXPR_SUB: printf ("-"); break;
+	case EXPR_MUL: printf ("*"); break;
+	case EXPR_DIV: printf ("/"); break;
+	case EXPR_MOD: printf ("%"); break;
+	case EXPR_NEG: printf ("-"); break;
+	case EXPR_NOT: printf ("~"); break;
+	case EXPR_OR: printf ("|"); break;
+	case EXPR_AND: printf ("&"); break;
+	case EXPR_XOR: printf ("^"); break;
+	case EXPR_SHL: printf ("<<"); break;
+	case EXPR_SHR: printf (">>"); break;
+	case EXPR_LOR: printf ("||"); break;
+	case EXPR_LAND: printf ("&&"); break;
+	case EXPR_LNOT: printf ("!"); break;
+	case EXPR_LT: printf ("<"); break;
+	case EXPR_GT: printf (">"); break;
+	case EXPR_LE: printf ("<="); break;
+	case EXPR_GE: printf (">="); break;
+	case EXPR_NE: printf ("!="); break;
+	case EXPR_IDENT: break;
+    }
+    switch (e->rtype) {
+	case EXPR_NUM: printf ("%d", e->right.num); break;
+	case EXPR_SYM: printf ("%s", e->right.sym->name); break;
+	case EXPR_EXPR: printf ("("); expr_print (e->right.expr); printf(")");
+	case EXPR_NONE: break;
+    }
+}
diff --git a/src/bison.y.in b/src/bison.y.in
index 72b0b96d..f1644f07 100644
--- a/src/bison.y.in
+++ b/src/bison.y.in
@@ -1,4 +1,4 @@
-/* $Id: bison.y.in,v 1.15 2001/07/05 07:21:35 peter Exp $
+/* $Id: bison.y.in,v 1.16 2001/07/05 08:37:59 mu Exp $
  * Main bison parser
  *
  *  Copyright (C) 2001  Peter Johnson, Michael Urman
@@ -26,6 +26,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 #define YYDEBUG 1
 
@@ -46,6 +47,7 @@ extern void yyerror(char *);
     } syminfo;
     unsigned char groupdata[3];
     effaddr ea_val;
+    expr *exp;
     immval im_val;
     bytecode bc;
 } 
@@ -83,7 +85,9 @@ extern void yyerror(char *);
 %type <ea_val> mem8 mem16 mem32 mem64 mem80 mem128 mem1632
 %type <ea_val> rm8x rm16x rm32x /*rm64x rm128x*/
 %type <ea_val> rm8 rm16 rm32 rm64 rm128
-%type <im_val> immexp imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <im_val> imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <exp> immexp
+%type <syminfo> immlabel
 %type <sym> label_id
 
 %left '-' '+'
@@ -271,10 +275,36 @@ rm128: XMMREG	{ (void)ConvertRegToEA(&$$, $1); }
 
 /* immediate values */
 /* TODO: formula expansion */
-immexp: INTNUM	{ (void)ConvertIntToImm(&$$, $1); }
-;
-
-imm: immexp
+immexp: /*INTNUM	{ (void)ConvertIntToImm(&$$, $1); } */
+	INTNUM		{ $$ = expr_new_ident (EXPR_NUM, $1); }
+    | immlabel		{ $$ = expr_new_ident (EXPR_SYM, sym_use_get ($1.name, SYM_LABEL)); }
+    /*| immexp '||' immexp	{ $$ = expr_new_tree ($1, EXPR_LOR, $3); }*/
+    | immexp '|' immexp	{ $$ = expr_new_tree ($1, EXPR_OR, $3); }
+    | immexp '^' immexp	{ $$ = expr_new_tree ($1, EXPR_XOR, $3); }
+    /*| immexp '&&' immexp	{ $$ = expr_new_tree ($1, EXPR_LAND, $3); }*/
+    | immexp '&' immexp	{ $$ = expr_new_tree ($1, EXPR_AND, $3); }
+    /*| immexp '==' immexp	{ $$ = expr_new_tree ($1, EXPR_EQUALS, $3); }*/
+    /*| immexp '>' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '<' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '>=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '<=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '!=' immexp	{ $$ = expr_new_tree ($1, EXPR_NE, $3); }*/
+    | immexp LEFT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHL, $3); }
+    | immexp RIGHT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHR, $3); }
+    | immexp '+' immexp	{ $$ = expr_new_tree ($1, EXPR_ADD, $3); }
+    | immexp '-' immexp	{ $$ = expr_new_tree ($1, EXPR_SUB, $3); }
+    | immexp '*' immexp	{ $$ = expr_new_tree ($1, EXPR_MUL, $3); }
+    | immexp '/' immexp	{ $$ = expr_new_tree ($1, EXPR_DIV, $3); }
+    | immexp '%' immexp	{ $$ = expr_new_tree ($1, EXPR_MOD, $3); }
+    | '-' immexp	{ $$ = expr_new_branch (EXPR_NEG, $2); }
+    /*| '!' immexp	{ $$ = expr_new_branch (EXPR_LNOT, $2); }*/
+    | '~' immexp	{ $$ = expr_new_branch (EXPR_NOT, $2); }
+    | '(' immexp ')'	{ $$ = $2; }
+;
+
+immlabel: ID | SPECIAL_ID | LOCAL_ID ;
+
+imm: immexp		{ expr_simplify ($1); ConvertExprToImm (&$$, $1); }
 ;
 
 /* explicit immediates */
diff --git a/src/bytecode.c b/src/bytecode.c
index f9d92a01..5812dbd2 100644
--- a/src/bytecode.c
+++ b/src/bytecode.c
@@ -1,4 +1,4 @@
-/* $Id: bytecode.c,v 1.8 2001/05/30 07:41:03 peter Exp $
+/* $Id: bytecode.c,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Bytecode utility functions
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -23,6 +23,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 static effaddr eff_static;
 static immval im_static;
@@ -70,10 +71,12 @@ effaddr *ConvertRegToEA(effaddr *ptr, unsigned long reg)
 
 effaddr *ConvertImmToEA(effaddr *ptr, immval *im_ptr, unsigned char im_len)
 {
+    int gotexprval;
     if(!ptr)
 	ptr = &eff_static;
 
-    ptr->disp = im_ptr->val;
+    /* FIXME: warn when gotexprval is 0, and/or die */
+    gotexprval = expr_get_value (im_ptr->val, &ptr->disp);
     if(im_ptr->len > im_len)
 	Warning(WARN_VALUE_EXCEEDS_BOUNDS, (char *)NULL, "word");
     ptr->len = im_len;
@@ -91,7 +94,8 @@ immval *ConvertIntToImm(immval *ptr, unsigned long int_val)
     if(!ptr)
 	ptr = &im_static;
 
-    ptr->val = int_val;
+    /* FIXME: this will leak expr's if static is used */
+    ptr->val = expr_new_ident(EXPR_NUM, int_val);
 
     if((int_val & 0xFF) == int_val)
 	ptr->len = 1;
@@ -106,6 +110,19 @@ immval *ConvertIntToImm(immval *ptr, unsigned long int_val)
     return ptr;
 }
 
+immval *ConvertExprToImm(immval *ptr, expr *expr_ptr)
+{
+    if(!ptr)
+	ptr = &im_static;
+
+    ptr->val = expr_ptr;
+
+    ptr->isrel = 0;
+    ptr->isneg = 0;
+
+    return ptr;
+}
+
 void SetEASegment(effaddr *ptr, unsigned char segment)
 {
     if(!ptr)
@@ -240,7 +257,9 @@ void DebugPrintBC(bytecode *bc)
 		(unsigned int)bc->data.insn.ea.valid_sib,
 		(unsigned int)bc->data.insn.ea.need_sib);
 	    printf("Immediate/Relative Value:\n");
-	    printf(" Val=%lx\n", bc->data.insn.imm.val);
+	    printf(" Val=");
+	    expr_print(bc->data.insn.imm.val);
+	    printf("\n");
 	    printf(" Len=%u, IsRel=%u, IsNeg=%u\n",
 		(unsigned int)bc->data.insn.imm.len,
 		(unsigned int)bc->data.insn.imm.isrel,
diff --git a/src/bytecode.h b/src/bytecode.h
index d17ec0a6..ce8ee6bd 100644
--- a/src/bytecode.h
+++ b/src/bytecode.h
@@ -1,4 +1,4 @@
-/* $Id: bytecode.h,v 1.8 2001/06/28 21:22:01 peter Exp $
+/* $Id: bytecode.h,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Bytecode utility functions header file
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -38,7 +38,7 @@ typedef struct effaddr_s {
 } effaddr;
 
 typedef struct immval_s {
-    unsigned long val;
+    struct expr_s *val;
 
     unsigned char len;		/* length of val (in bytes), 0 if none */
     unsigned char isrel;
diff --git a/src/expr.c b/src/expr.c
index e6210957..0d7f7221 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -1,4 +1,4 @@
-/* $Id: expr.c,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.c,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling
  *
  *  Copyright (C) 2001  Michael Urman
@@ -189,3 +189,58 @@ int expr_simplify (expr *e)
 
     return simplified;
 }
+
+int expr_get_value (expr *e, unsigned long *retval)
+{
+    while (!(e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+	   && expr_simplify (e));
+
+    if (e->op == EXPR_IDENT && e->rtype == EXPR_NUM)
+    {
+	*retval = e->right.num;
+	return 1;
+    }
+    else
+	return 0;
+}
+
+void expr_print (expr *e)
+{
+    if (e->op != EXPR_IDENT) {
+	switch (e->ltype) {
+	    case EXPR_NUM: printf ("%d", e->left.num); break;
+	    case EXPR_SYM: printf ("%s", e->left.sym->name); break;
+	    case EXPR_EXPR: printf ("("); expr_print (e->left.expr); printf(")");
+	    case EXPR_NONE: break;
+	}
+    }
+    switch (e->op) {
+	case EXPR_ADD: printf ("+"); break;
+	case EXPR_SUB: printf ("-"); break;
+	case EXPR_MUL: printf ("*"); break;
+	case EXPR_DIV: printf ("/"); break;
+	case EXPR_MOD: printf ("%"); break;
+	case EXPR_NEG: printf ("-"); break;
+	case EXPR_NOT: printf ("~"); break;
+	case EXPR_OR: printf ("|"); break;
+	case EXPR_AND: printf ("&"); break;
+	case EXPR_XOR: printf ("^"); break;
+	case EXPR_SHL: printf ("<<"); break;
+	case EXPR_SHR: printf (">>"); break;
+	case EXPR_LOR: printf ("||"); break;
+	case EXPR_LAND: printf ("&&"); break;
+	case EXPR_LNOT: printf ("!"); break;
+	case EXPR_LT: printf ("<"); break;
+	case EXPR_GT: printf (">"); break;
+	case EXPR_LE: printf ("<="); break;
+	case EXPR_GE: printf (">="); break;
+	case EXPR_NE: printf ("!="); break;
+	case EXPR_IDENT: break;
+    }
+    switch (e->rtype) {
+	case EXPR_NUM: printf ("%d", e->right.num); break;
+	case EXPR_SYM: printf ("%s", e->right.sym->name); break;
+	case EXPR_EXPR: printf ("("); expr_print (e->right.expr); printf(")");
+	case EXPR_NONE: break;
+    }
+}
diff --git a/src/expr.h b/src/expr.h
index 18d6eee1..3ca1ec68 100644
--- a/src/expr.h
+++ b/src/expr.h
@@ -1,4 +1,4 @@
-/* $Id: expr.h,v 1.1 2001/07/05 06:28:54 mu Exp $
+/* $Id: expr.h,v 1.2 2001/07/05 08:37:59 mu Exp $
  * Expression handling header file
  *
  *  Copyright (C) 2001  Michael Urman
@@ -57,7 +57,7 @@ typedef enum {
 typedef union expritem_u {
     struct symrec_s *sym;
     struct expr_s *expr;
-    int num;
+    unsigned long num;
 } ExprItem;
 
 typedef struct expr_s {
@@ -67,6 +67,20 @@ typedef struct expr_s {
 } expr;
 
 expr *expr_new (ExprType, ExprItem, ExprOp, ExprType, ExprItem);
+/*expr *expr_new_tree (ExprItem, ExprOp, ExprItem);
+expr *expr_new_branch (ExprOp, ExprItem);
+expr *expr_new_ident (ExprType, ExprItem);*/
+#define expr_new_tree(l,o,r) \
+    expr_new (EXPR_EXPR, (ExprItem)(l), (ExprOp)(o), EXPR_EXPR, (ExprItem)(r))
+#define expr_new_branch(o,r) \
+    expr_new (EXPR_NONE, (ExprItem)0UL, (ExprOp)(o), EXPR_EXPR, (ExprItem)(r))
+#define expr_new_ident(t,r) \
+    expr_new (EXPR_NONE, (ExprItem)0UL, EXPR_IDENT, (ExprType)(t), (ExprItem)(r))
 int expr_simplify (expr *);
 
+void expr_print (expr *);
+
+/* get the value if possible.  return value is IF POSSIBLE, not the val */
+int expr_get_value (expr *, unsigned long *);
+
 #endif
diff --git a/src/parsers/nasm/bison.y.in b/src/parsers/nasm/bison.y.in
index 72b0b96d..f1644f07 100644
--- a/src/parsers/nasm/bison.y.in
+++ b/src/parsers/nasm/bison.y.in
@@ -1,4 +1,4 @@
-/* $Id: bison.y.in,v 1.15 2001/07/05 07:21:35 peter Exp $
+/* $Id: bison.y.in,v 1.16 2001/07/05 08:37:59 mu Exp $
  * Main bison parser
  *
  *  Copyright (C) 2001  Peter Johnson, Michael Urman
@@ -26,6 +26,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 #define YYDEBUG 1
 
@@ -46,6 +47,7 @@ extern void yyerror(char *);
     } syminfo;
     unsigned char groupdata[3];
     effaddr ea_val;
+    expr *exp;
     immval im_val;
     bytecode bc;
 } 
@@ -83,7 +85,9 @@ extern void yyerror(char *);
 %type <ea_val> mem8 mem16 mem32 mem64 mem80 mem128 mem1632
 %type <ea_val> rm8x rm16x rm32x /*rm64x rm128x*/
 %type <ea_val> rm8 rm16 rm32 rm64 rm128
-%type <im_val> immexp imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <im_val> imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <exp> immexp
+%type <syminfo> immlabel
 %type <sym> label_id
 
 %left '-' '+'
@@ -271,10 +275,36 @@ rm128: XMMREG	{ (void)ConvertRegToEA(&$$, $1); }
 
 /* immediate values */
 /* TODO: formula expansion */
-immexp: INTNUM	{ (void)ConvertIntToImm(&$$, $1); }
-;
-
-imm: immexp
+immexp: /*INTNUM	{ (void)ConvertIntToImm(&$$, $1); } */
+	INTNUM		{ $$ = expr_new_ident (EXPR_NUM, $1); }
+    | immlabel		{ $$ = expr_new_ident (EXPR_SYM, sym_use_get ($1.name, SYM_LABEL)); }
+    /*| immexp '||' immexp	{ $$ = expr_new_tree ($1, EXPR_LOR, $3); }*/
+    | immexp '|' immexp	{ $$ = expr_new_tree ($1, EXPR_OR, $3); }
+    | immexp '^' immexp	{ $$ = expr_new_tree ($1, EXPR_XOR, $3); }
+    /*| immexp '&&' immexp	{ $$ = expr_new_tree ($1, EXPR_LAND, $3); }*/
+    | immexp '&' immexp	{ $$ = expr_new_tree ($1, EXPR_AND, $3); }
+    /*| immexp '==' immexp	{ $$ = expr_new_tree ($1, EXPR_EQUALS, $3); }*/
+    /*| immexp '>' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '<' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '>=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '<=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '!=' immexp	{ $$ = expr_new_tree ($1, EXPR_NE, $3); }*/
+    | immexp LEFT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHL, $3); }
+    | immexp RIGHT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHR, $3); }
+    | immexp '+' immexp	{ $$ = expr_new_tree ($1, EXPR_ADD, $3); }
+    | immexp '-' immexp	{ $$ = expr_new_tree ($1, EXPR_SUB, $3); }
+    | immexp '*' immexp	{ $$ = expr_new_tree ($1, EXPR_MUL, $3); }
+    | immexp '/' immexp	{ $$ = expr_new_tree ($1, EXPR_DIV, $3); }
+    | immexp '%' immexp	{ $$ = expr_new_tree ($1, EXPR_MOD, $3); }
+    | '-' immexp	{ $$ = expr_new_branch (EXPR_NEG, $2); }
+    /*| '!' immexp	{ $$ = expr_new_branch (EXPR_LNOT, $2); }*/
+    | '~' immexp	{ $$ = expr_new_branch (EXPR_NOT, $2); }
+    | '(' immexp ')'	{ $$ = $2; }
+;
+
+immlabel: ID | SPECIAL_ID | LOCAL_ID ;
+
+imm: immexp		{ expr_simplify ($1); ConvertExprToImm (&$$, $1); }
 ;
 
 /* explicit immediates */
diff --git a/src/parsers/nasm/nasm-bison.y b/src/parsers/nasm/nasm-bison.y
index 7a32a80e..6c1a66bb 100644
--- a/src/parsers/nasm/nasm-bison.y
+++ b/src/parsers/nasm/nasm-bison.y
@@ -1,4 +1,4 @@
-/* $Id: nasm-bison.y,v 1.15 2001/07/05 07:21:35 peter Exp $
+/* $Id: nasm-bison.y,v 1.16 2001/07/05 08:37:59 mu Exp $
  * Main bison parser
  *
  *  Copyright (C) 2001  Peter Johnson, Michael Urman
@@ -26,6 +26,7 @@
 #include "globals.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 
 #define YYDEBUG 1
 
@@ -46,6 +47,7 @@ extern void yyerror(char *);
     } syminfo;
     unsigned char groupdata[3];
     effaddr ea_val;
+    expr *exp;
     immval im_val;
     bytecode bc;
 } 
@@ -83,7 +85,9 @@ extern void yyerror(char *);
 %type <ea_val> mem8 mem16 mem32 mem64 mem80 mem128 mem1632
 %type <ea_val> rm8x rm16x rm32x /*rm64x rm128x*/
 %type <ea_val> rm8 rm16 rm32 rm64 rm128
-%type <im_val> immexp imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <im_val> imm imm8x imm16x imm32x imm8 imm16 imm32
+%type <exp> immexp
+%type <syminfo> immlabel
 %type <sym> label_id
 
 %left '-' '+'
@@ -271,10 +275,36 @@ rm128: XMMREG	{ (void)ConvertRegToEA(&$$, $1); }
 
 /* immediate values */
 /* TODO: formula expansion */
-immexp: INTNUM	{ (void)ConvertIntToImm(&$$, $1); }
-;
-
-imm: immexp
+immexp: /*INTNUM	{ (void)ConvertIntToImm(&$$, $1); } */
+	INTNUM		{ $$ = expr_new_ident (EXPR_NUM, $1); }
+    | immlabel		{ $$ = expr_new_ident (EXPR_SYM, sym_use_get ($1.name, SYM_LABEL)); }
+    /*| immexp '||' immexp	{ $$ = expr_new_tree ($1, EXPR_LOR, $3); }*/
+    | immexp '|' immexp	{ $$ = expr_new_tree ($1, EXPR_OR, $3); }
+    | immexp '^' immexp	{ $$ = expr_new_tree ($1, EXPR_XOR, $3); }
+    /*| immexp '&&' immexp	{ $$ = expr_new_tree ($1, EXPR_LAND, $3); }*/
+    | immexp '&' immexp	{ $$ = expr_new_tree ($1, EXPR_AND, $3); }
+    /*| immexp '==' immexp	{ $$ = expr_new_tree ($1, EXPR_EQUALS, $3); }*/
+    /*| immexp '>' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '<' immexp	{ $$ = expr_new_tree ($1, EXPR_GT, $3); }*/
+    /*| immexp '>=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '<=' immexp	{ $$ = expr_new_tree ($1, EXPR_GE, $3); }*/
+    /*| immexp '!=' immexp	{ $$ = expr_new_tree ($1, EXPR_NE, $3); }*/
+    | immexp LEFT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHL, $3); }
+    | immexp RIGHT_OP immexp	{ $$ = expr_new_tree ($1, EXPR_SHR, $3); }
+    | immexp '+' immexp	{ $$ = expr_new_tree ($1, EXPR_ADD, $3); }
+    | immexp '-' immexp	{ $$ = expr_new_tree ($1, EXPR_SUB, $3); }
+    | immexp '*' immexp	{ $$ = expr_new_tree ($1, EXPR_MUL, $3); }
+    | immexp '/' immexp	{ $$ = expr_new_tree ($1, EXPR_DIV, $3); }
+    | immexp '%' immexp	{ $$ = expr_new_tree ($1, EXPR_MOD, $3); }
+    | '-' immexp	{ $$ = expr_new_branch (EXPR_NEG, $2); }
+    /*| '!' immexp	{ $$ = expr_new_branch (EXPR_LNOT, $2); }*/
+    | '~' immexp	{ $$ = expr_new_branch (EXPR_NOT, $2); }
+    | '(' immexp ')'	{ $$ = $2; }
+;
+
+immlabel: ID | SPECIAL_ID | LOCAL_ID ;
+
+imm: immexp		{ expr_simplify ($1); ConvertExprToImm (&$$, $1); }
 ;
 
 /* explicit immediates */
diff --git a/src/parsers/nasm/token.l.in b/src/parsers/nasm/token.l.in
index 4aa92c49..2a19cdc8 100644
--- a/src/parsers/nasm/token.l.in
+++ b/src/parsers/nasm/token.l.in
@@ -1,4 +1,4 @@
-/* $Id: token.l.in,v 1.8 2001/06/29 05:11:40 peter Exp $
+/* $Id: token.l.in,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Main lexer
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -34,6 +34,7 @@
 #include "symrec.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 #include "bison.h"
 
 %}
diff --git a/src/token.l.in b/src/token.l.in
index 4aa92c49..2a19cdc8 100644
--- a/src/token.l.in
+++ b/src/token.l.in
@@ -1,4 +1,4 @@
-/* $Id: token.l.in,v 1.8 2001/06/29 05:11:40 peter Exp $
+/* $Id: token.l.in,v 1.9 2001/07/05 08:37:59 mu Exp $
  * Main lexer
  *
  *  Copyright (C) 2001  Peter Johnson
@@ -34,6 +34,7 @@
 #include "symrec.h"
 #include "bytecode.h"
 #include "errwarn.h"
+#include "expr.h"
 #include "bison.h"
 
 %}