Merge branch 'master' into develop

Author: BenoitStef

hdl/psi_common_math_pkg.vhd

@@ -12,9 +12,6 @@ use ieee.std_logic_1164.all;
 use ieee.numeric_std.all;
 use ieee.math_real.all;
 
-library std;
-use std.textio.all;
-
 library work;
 use work.psi_common_array_pkg.all;
 
@@ -400,12 +397,75 @@ package body psi_common_math_pkg is
 
   -- convert string to real
   function from_str(input : string) return real is
-    variable line_v : line := new string'(input);
-    variable v      : real;
+    constant Nbsp_c : character := character'val(160);
+    variable Idx_v : integer := input'low;
+    variable IsNeg_v : boolean := false;
+    variable ValInt_v : integer := 0;
+    variable ValFrac_v : real := 0.0;
+    variable FracDigits_v : integer := 0;
+    variable Exp_v : integer := 0;
+    variable ExpNeg_v : boolean := false;
+    variable ValAbs_v : real := 0.0;
   begin
-    read(line_v, v);
-    deallocate(line_v);
-    return v;
+    -- skip leading white-spaces (space, non-breaking space or horizontal tab)
+    while (Idx_v <= input'high) and (input(Idx_v) = ' ' or input(Idx_v) = Nbsp_c or input(Idx_v) = HT) loop
+      Idx_v := Idx_v + 1;
+    end loop;
+    
+    -- Check sign
+    if (Idx_v <= input'high) and ((input(Idx_v) = '-') or (input(Idx_v) = '+')) then
+      IsNeg_v := (input(Idx_v) = '-');
+      Idx_v := Idx_v + 1;
+    end if;
+    
+    -- Parse Integer
+    while (Idx_v <= input'high) and (input(Idx_v) <= '9') and (input(Idx_v) >= '0') loop
+      ValInt_v := ValInt_v*10 + (character'pos(input(Idx_v))-character'pos('0'));
+      Idx_v := Idx_v + 1;
+    end loop;
+    
+    -- Check decimal point
+    if (Idx_v <= input'high) then
+      if input(Idx_v) = '.' then
+        Idx_v := Idx_v + 1;
+    
+        -- Parse Fractional
+        while (Idx_v <= input'high) and (input(Idx_v) <= '9') and (input(Idx_v) >= '0') loop
+          ValFrac_v := ValFrac_v*10.0 + real((character'pos(input(Idx_v))-character'pos('0')));
+          FracDigits_v := FracDigits_v + 1;
+          Idx_v := Idx_v + 1;
+        end loop;
+      end if;
+    end if;
+    
+    -- Check exponent
+    if (Idx_v <= input'high) then
+      if (input(Idx_v) = 'E') or (input(Idx_v) = 'e') then
+        Idx_v := Idx_v + 1;
+        -- Check sign
+        if (Idx_v <= input'high) and ((input(Idx_v) = '-') or (input(Idx_v) = '+')) then
+          ExpNeg_v := (input(Idx_v) = '-');
+          Idx_v := Idx_v + 1;
+        end if;
+        
+        -- Parse Integer
+        while (Idx_v <= input'high) and (input(Idx_v) <= '9') and (input(Idx_v) >= '0') loop
+          Exp_v := Exp_v*10 + (character'pos(input(Idx_v))-character'pos('0'));
+          Idx_v := Idx_v + 1;
+        end loop;
+        if ExpNeg_v then
+          Exp_v := -Exp_v;
+        end if;
+      end if;
+    end if;
+    
+    -- Return
+    ValAbs_v := (real(ValInt_v)+ValFrac_v/10.0**real(FracDigits_v))*10.0**real(Exp_v);
+    if IsNeg_v then
+      return -ValAbs_v;
+    else
+      return ValAbs_v;
+    end if; 
   end function;
 
   -- convert string to real array