; #########################################################################
;
;                         FPU Determinants
;
;##########################################################################
;
; Procedure to evaluate a NxN determinant
;
; lpSrc = pointer to array of the determinant's data
; uSize = size N of the determinant (N is the rows/columns number)
; uType = type of the data
;           0 = DWORD
;           1 = QWORD
;           2 = REAL4
;           3 = REAL8
;           4 = REAL10
;
; The result is returned in ST(0) on the FPU.
;
; The original determinant's data is not modified.
;
; -----------------------------------------------------------------------

    .386
    .model flat, stdcall  ; 32 bit memory model
    option casemap :none  ; case sensitive

      include E:\masm32\include\windows.inc

      include E:\masm32\include\kernel32.inc
      includelib E:\masm32\lib\kernel32.lib

; The above is simply to indicate the minimum requirements.
; Do not repeat if you paste the proc in your app.

; #########################################################################
	.data
	M	REAL4 2.0
		REAL4 2.0
		REAL4 3.0
		REAL4 4.0
		REAL4 5.0
		REAL4 6.0
		REAL4 7.0
		REAL4 8.0
		REAL4 9.0

	V	REAL4 1.0
		REAL4 2.0
		REAL4 3.0
	.code
FpuDet PROTO STDCALL, lpSrc:DWORD, uSize:DWORD, uType:DWORD

main proc
	invoke FpuDet, addr M, 3, 2
	db 0CCh ; rF
	ret
main endp

FpuDet proc public uses ebx esi edi lpSrc:DWORD, uSize:DWORD, uType:DWORD

LOCAL hMem  :DWORD

      mov   eax,uSize
      mul   eax
      push  eax
      imul  eax,10
      invoke LocalAlloc,LPTR,eax
      mov   hMem,eax
      mov   edi,eax
      mov   esi,lpSrc
      pop   ecx
      .if   uType == 0
       @@:
          fild  dword ptr[esi]
          fstp  tbyte ptr[edi]
          add   esi,4
          add   edi,10
          dec   ecx
          jnz   @B
      .elseif uType == 1
       @@:
          fild  qword ptr[esi]
          fstp  tbyte ptr[edi]
          add   esi,8
          add   edi,10
          dec   ecx
          jnz   @B
      .elseif uType == 2
       @@:
          fld  dword ptr[esi]
          fstp  tbyte ptr[edi]
          add   esi,4
          add   edi,10
          dec   ecx
          jnz   @B
      .elseif uType == 3
       @@:
          fld  qword ptr[esi]
          fstp  tbyte ptr[edi]
          add   esi,8
          add   edi,10
          dec   ecx
          jnz   @B
      .elseif uType == 4
            imul  ecx,5
            rep   movsw
      .endif

      fld1
      mov   ebx,uSize
det0:
      mov   eax,uSize
      sub   eax,ebx
      mul   uSize
      imul  eax,10
      mov   edx,uSize
      sub   edx,ebx
      imul  edx,10
      add   eax,edx
      mov   esi,hMem
      add   esi,eax
      mov   edi,uSize
      imul  edi,10
      add   edi,esi

      fld   tbyte ptr[esi]
      fmul  st(1),st
      mov   ecx,ebx
      dec   ecx
      jnz   @F
      fstp  st
      invoke LocalFree,hMem
      ret

   @@:
      mov   edx,ecx
det1:
      fld   tbyte ptr[edi]
      fdiv  st,st(1)
      push  edi
      push  esi
      push  edx
det2:
      add   esi,10
      add   edi,10
      fld   tbyte ptr[esi]
      fmul  st,st(1)
      fld   tbyte ptr[edi]
      fsubr
      fstp  tbyte ptr[edi]
      dec   edx
      jnz   det2
      pop   edx
      pop   esi
      pop   edi
      mov   eax,uSize
      imul  eax,10
      add   edi,eax
      fstp  st
      dec   ecx
      jnz   det1
      fstp  st
      dec   ebx
      jmp   det0

FpuDet endp
end main