Math Processor Unit Library

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+.\" Copyright 2024 Andrew V.Kosteltsev (kx@radix-linux.su)
+.\"
+.\"
+.TH iadd 3  "December 27, 2024" "libmpu" "LibMPU Programmer's Manual"
+.SH NAME
+\fBiadd\fP \- signed and unsigned addition
+.SH SYNOPSIS
+.nf
+.B #include <libmpu.h>
+.PP
+.BI "void iadd( mpu_int *" c ", mpu_int *" a ", mpu_int *" b ", int " nb " );
+.fi
+.SH DESCRIPTION
+The \fBiadd()\fP function performs the operation of addition of integers located at addresses \fBa\fP and
+\fBb\fP, with the result placed at address \fBc\fP. The operands can be numbers with or without a sign.
+The memory contents at addresses \fBa\fP, \fBb\fP are not changed, the previous memory contents at address
+\fBc\fP are lost. The \fBnb\fP parameter defines the size in bytes of the operands located at addresses
+\fBc\fP, \fBa\fP, \fBb\fP.
+.PP
+The function affects the flags \fBA\fP, \fBC\fP, \fBO\fP, \fBP\fP, \fBS\fP, \fBZ\fP, and \fBV\fP.
+.PP
+Flags \fBА\fP and \fBP\fP are set only when the size of operands \fBa\fP, \fBb\fP is one or
+two bytes (\fBnb\fP == 1 || \fBnb\fP == 2).
+.sp
+.SH EXAMPLES
+.nf
+.sp
+#include <libmpu.h>
+#include <stdio.h>
+
+int main( void )
+{
+  int  rc = 0;
+
+  __mpu_init();
+  __mpu_extra_warnings = 1;
+
+  {
+    mpu_int128_t   c, a, b;
+    int            nb = NB_I128;
+    __mpu_char8_t  s[256];
+
+    iatoi( a, "237", nb ); /* evaluate the A variable */
+    iatoi( b,  "37", nb ); /* evaluate the B variable */
+
+    iadd( c, a, b, nb );
+    iitoa( s, c, RADIX_DEC, LOWERCASE, nb ); /* convert C value to ASCII string S */
+    printf( "c = %s;\\n", s ); /* c = 274; */
+  }
+
+  __mpu_free_context();
+
+  return( rc );
+}
+.fi
+.sp
+.SH SEE ALSO
+.BR iadc (3),
+.BR isub (3),
+.BR isbb (3).
+