From e6e0396ecbf855acaf2a9e9f35a9350e154baab2 Mon Sep 17 00:00:00 2001
From: steve <steve>
Date: Wed, 5 Mar 2003 03:45:01 +0000
Subject: [PATCH]  Restore verireal constructor to match vvp processing of
 reals.

---
 verireal.cc | 66 ++++++++++++++++++++++++++++++++++++++++-------------
 1 file changed, 50 insertions(+), 16 deletions(-)

diff --git a/verireal.cc b/verireal.cc
index 1f1f4a897..0bfc26450 100644
--- a/verireal.cc
+++ b/verireal.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1999-2003 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 1999 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -17,7 +17,7 @@
  *    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  */
 #ifdef HAVE_CVS_IDENT
-#ident "$Id: verireal.cc,v 1.12 2003/03/05 02:36:05 steve Exp $"
+#ident "$Id: verireal.cc,v 1.13 2003/03/05 03:45:01 steve Exp $"
 #endif
 
 # include "config.h"
@@ -28,7 +28,6 @@
 # include  <iostream>
 # include  <math.h>
 # include  <assert.h>
-# include  <stdio.h>
 
 verireal::verireal()
 {
@@ -37,23 +36,58 @@ verireal::verireal()
 
 verireal::verireal(const char*txt)
 {
-      char*buf = new char[strlen(txt)+1];
-      char*cp = buf;
+      unsigned long long mant = 0;
+      bool sign = false;
+      signed int exp10 = 0;
 
-      /* filter out Verilog-isms */
-      for (unsigned i = 0; txt[i]; i += 1) {
-	    if (txt[i] == '_') { continue; }
-	    *cp = txt[i]; cp++;
+      const char*ptr = txt;
+      for (  ; *ptr ;  ptr += 1) {
+	    if (*ptr == '.') break;
+	    if (*ptr == 'e') break;
+	    if (*ptr == 'E') break;
+	    if (*ptr == '_') continue;
+
+	    assert(isdigit(*ptr));
+
+	    mant *= 10;
+	    mant += *ptr - '0';
       }
 
-      *cp = '\0';
+      if (*ptr == '.') {
+	    ptr += 1;
+	    for ( ; *ptr ; ptr += 1) {
+		  if (*ptr == 'e') break;
+		  if (*ptr == 'E') break;
+		  if (*ptr == '_') continue;
 
-      if (sscanf(buf, "%lf", &value_) != 1) {
-	 fprintf(stderr, "PANIC: Unable to sscanf(%s)\n", txt);
-         assert(0);
+		  assert(isdigit(*ptr));
+
+		  mant *= 10;
+		  mant += *ptr - '0';
+		  exp10 -= 1;
+	    }
       }
 
-      delete[]buf;
+      if ((*ptr == 'e') || (*ptr == 'E')) {
+	    ptr += 1;
+	    long tmp = 0;
+	    bool sflag = false;
+	    if (*ptr == '+') {ptr += 1; sflag = false;}
+	    if (*ptr == '-') {ptr += 1; sflag = true;}
+
+	    for ( ; *ptr ;  ptr += 1) {
+		  if (*ptr == '_') continue;
+		  assert(isdigit(*ptr));
+		  tmp *= 10;
+		  tmp += *ptr - '0';
+	    }
+
+	    exp10 += sflag? -tmp : +tmp;
+      }
+
+      assert(*ptr == 0);
+
+      value_ = pow(10.0,exp10) * mant * (sign? -1.0 : 1.0);
 }
 
 verireal::verireal(long val)
@@ -130,8 +164,8 @@ ostream& operator<< (ostream&out, const verireal&v)
 
 /*
  * $Log: verireal.cc,v $
- * Revision 1.12  2003/03/05 02:36:05  steve
- *  Use sscanf to make doubles from strings.
+ * Revision 1.13  2003/03/05 03:45:01  steve
+ *  Restore verireal constructor to match vvp processing of reals.
  *
  * Revision 1.11  2003/02/07 06:13:44  steve
  *  Store real values as native double.