Math Processor Unit Library

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+.TH ismul 3  "December 27, 2024" "libmpu" "LibMPU Programmer's Manual"
+.SH NAME
+\fBismul\fP \- signed multiplication of integers
+.SH SYNOPSIS
+.nf
+.B #include <libmpu.h>
+.PP
+.BI "void ismul( mpu_int *" prod ", mpu_int *" num ", mpu_int *" mul ", int " nb_prod ", int " nb_num " );
+.fi
+.SH DESCRIPTION
+The function \fBismul()\fP performs the multiplication operation of the variable located
+at the address \fBnum\fP by the variable located at the address \fBmul\fP, taking into account
+the sign of the variables. The result is placed at \fBprod\fP. The contents of the memory at
+\fBnum\fP, \fBmul\fP are not changed, the previous memory contents at \fBprod\fP are lost.
+The parameter \fBnb_prod\fP determines the size of the operand (in bytes) located at the
+address \fBprod\fP, and the parameter \fBnb_num\fP defines the size of operands (in bytes)
+located at the addresses \fBnum\fP, \fBmul\fP.
+.PP
+The function affects the flags \fBA\fP, \fBC\fP, \fBO\fP, \fBP\fP, \fBS\fP, \fBZ\fP, \fBR\fP.
+.PP
+The \fBA\fP flag is reset to 0. The \fBP\fP flag is set only when the size of the \fBprod\fP
+operand is one or two bytes (\fBnb\fP == 1 || \fBnb\fP == 2). Flag \fBR\fP (major || remainder)
+is set in the case that the resulting product requires a larger size than the \fBnb_prod\fP
+parameter.
+.sp
+.SH SEE ALSO
+.BR iadd(3),
+.BR isub(3),
+.BR iadc(3),
+.BR isbb(3),
+.BR ishl(3),
+.BR ishr(3),
+.BR isal(3),
+.BR isar(3),
+.BR irol(3),
+.BR iror(3),
+.BR ircl(3),
+.BR ircr(3),
+.BR ishln(3),
+.BR ishrn(3),
+.BR isaln(3),
+.BR isarn(3),
+.BR iroln(3),
+.BR irorn(3),
+.BR ircln(3),
+.BR ircrn(3),
+.BR ineg(3),
+.BR inot(3),
+.BR iand(3),
+.BR itest(3),
+.BR icmp(3),
+.BR ior(3),
+.BR ixor(3),
+.BR iinc(3),
+.BR idec(3),
+.BR ixchg(3),
+.BR icpy(3),
+.BR icvt(3),
+.BR imul(3),
+.BR idiv(3),
+.BR isdiv(3),
+.BR iatoi(3),
+.BR iatoui(3),
+.BR iitoa(3),
+.BR iuitoa(3).