From efa24b220d9633d5d7bfef632b33df180dcb0e74 Mon Sep 17 00:00:00 2001
From: FreeArtMan <dos21h@gmail.com>
Date: Thu, 27 May 2021 21:10:45 +0100
Subject: Update 10 html to md articles

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+title:Assembler calculate polynomial
+keywords:assembler,c,math,polynomial
+
+# Assembler calculate polynomial
+Calculating polynomial with asm and C
+
+```asm
+format ELF
+section ".text" executable
+public poly
+align 4
+poly:
+a equ dword [ebp+8]
+b equ dword [ebp+12]
+c equ dword [ebp+16]
+x equ dword [ebp+20]
+    ;a*x*x+b*x+c
+    push ebp
+    mov ebp , esp
+    fld c
+    fld x
+    fld b
+    fld x
+    fld a
+    fmulp st1 , st0
+    faddp st1 , st0
+    fmulp st1 , st0
+    faddp st1 , st0
+    pop ebp
+    ret
+```
+
+For calculating polynomial used polish notation
+Wiki
+In other words a*x*x+b*x+c to reduce operations changed to (a*x+b)*x+c
+and then written out operation by priorities [*,+,*,+].
+Compiling this with lines
+
+```
+fasm poly.asm poly.o
+```
+
+```c
+#include <stdio.h>
+extern float poly( float , float , float , float );
+int main()
+{
+    float res = poly( 1.0 , 2.0 , 3.0 , 3.0 );
+    printf( "%f\n" , res );
+    return 0;
+}
+```
+
+
+Compiling this with lines
+```
+gcc -c main.c -o main.o
+```
+Combining
+```
+gcc main.o poly.o -o main
+```
+Update on 06.12.2009
+After running dome C code with FPU calculations and -O2 flag 
+
+```asm
+format ELF
+section ".text" executable
+ 
+public poly
+align 4
+poly:
+a equ dword [ebp+8]
+b equ dword [ebp+12]
+c equ dword [ebp+16]
+x equ dword [ebp+20]
+    ;a*x*x+b*x+c
+    push ebp
+    mov ebp , esp
+ 
+    fld a
+    fmul x
+    fadd b
+    fmul x
+    fadd c
+     
+    pop ebp
+    ret
+```
+
+Now only 5 instructions
+
+
+# Links
+http://en.wikipedia.org/wiki/Polish_notation
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