There are a number of global compiler definitions. Most of these should not be changed. One configuration that can be changed is memory allocation.

System memory used for floating point number variables are defined in math.asm using RESQ statements to declare uninitialized blocks of memory in the BSS section. These are statically allocated when the program is started as part of the load image. The maximum size of the floating point variables can be configured in "var_header.inc". As shown below, the default variable size is about 40 million decimal digits. It is suggested to uncomment one of the following lines. The image contains 17 variables of this size. It is necessary to recompile the binary after this is changed using the make command.

File: var_header.inc

; Variable size and Exponent size must be multiple of 4 byte (32 bit) DWord
;
;VAR_WSIZE  equ 0x010     ;Size of variable in words (~250  Digits)
;VAR_WSIZE  equ 0x0100    ;Size of variable in words (~  4 KDigits)
;VAR_WSIZE  equ 0x01000   ;Size of variable in words (~ 75 KDigits)
;VAR_WSIZE  equ 0x010000  ;Size of variable in words (1.26 MDigits)
;VAR_WSIZE  equ 0x040000  ;Size of variable in words ( ~5 MDigits)
;VAR_WSIZE  equ 0x0100000 ;Size of variable in words (~20 MDigits)
VAR_WSIZE  equ 0x0200000 ;Size of variable in words (~40 MDigits)      <-- Default
;VAR_WSIZE  equ 0x0400000 ;Size of variable in words (~80.8 MDigits)
;VAR_WSIZE  equ 0x0800000 ;Size of variable in words (~161  MDigits)

The backbone of this program is a series of binary bitwise arithmetic functions used for multiplication and division. These are conventional multi-precisions routines bitwise rotations combined with addition and subtraction. However, this method is extremely slow. In order to increase speed, alternate multiplication and division routines can use the 64 bit microprocessor MUL and DIV instruction to work with 128 bit / 64 bit integer operations.

The "mmode" command is used to set or view a series of flags used to select or de-select various alternate arithmetic methods. The default value of mmode is 0.

For example, calculation of Pi using Chudnovsky formula to 100,000 digits:
Time 10 seconds (mmode=0)
Time 652 Seconds (mmode 463, full bitwise arithmetic)

To view the options, type: "help mmode"

Usage: mmode <optional integer bit pattern>

Description: Without argument, mmode displays MathMode variable.
Using mmode with argument will load the integer argument into
the MathMode variable.

Modes:
   1   (0x01)  Force: FP_Long_Mult (binary shift and add)
   2   (0x02)  Force: FP_Long_Div (binary shift and subtract)
   4   (0x04)  Disable: 64 bit i7 MUL with single word non-zero.
   8   (0x08)  Disable: 64 bit i7 DIV with single word non-zero.
   16  (0x10)  FP_Reciprocal: Disable variable accuracy.
   32  (0x20)  FP_Reciprocal: bitwise multiplication.
   64  (0x40)  FP_Addition: Force bitwise alignment
   128 (0x80)  FP_Normalization: Force bitwise alignment
   256 (0x100) Disable function ReduceSeriesAccuracy during summations

   Use 0 to select normal (most efficient) mode.
   Use 12 to force matrix mode (disable auto short).
   Use 15 to force binary long mode.
   Use 463 for full bitwise arithmetic (for benchmarking).