[Mspgcc-users] How the hardware multiplier work in the mspgcc?

[penguinfly]

Hi,everybody:
Excuse me! English is not my first language. I'm chinese.
It is hard to express my meanings clearly with my poor english.
I lvoe the mspgcc, but there are some troubles When I useing 
16-bit multiplication in f147 and fe427. The result of the 16-bit 
multiplication should be 32-bit, but the compiler only read 
the register 0x013a(RESLO). Is this a bug or something wrong
when i useing the hardware multiplier?
By the way, is it necessary to add "#define __msp430_have_fll"
in msp430xE42x.h?
(mspgcc-20060407,win2000/xp)
   
   
   mian.c:
uint16_t vara,varb,varc;
void dispLED(uint16_t);
...
int main(void)
{
...
vara=0x6000;
varb=0x5000;
varc = varb * vara / 0x7000;
dispLED(varc);
...
}

Part of the Assemble List:
vara=0x6000;

    81bc: b2 40 00 60 mov #24576, &0x020c ;#0x6000
    81c0: 0c 02 
varb=0x5000;

    81c2: b2 40 00 50 mov #20480, &0x0208 ;#0x5000
    81c6: 08 02 
varc = varb * vara / 0x7000;

    81c8: 02 12          push r2 ;
    81ca: 32 c2          dint 
    81cc: 03 43          nop 
    81ce: b2 40 00 50 mov #20480, &0x0132 ;#0x5000
    81d2: 32 01 
    81d4: b2 40 00 60 mov #24576, &0x0138 ;#0x6000
    81d8: 38 01 
    81da: 1f 42 3a 01 mov &0x013a,r15 ;0x013a
    81de: 32 41          pop r2 ;
    81e0: 0c 4f           mov r15, r12 ;
    81e2: 3a 40 00 70 mov #28672, r10 ;#0x7000
    81e6: b0 12 dc 82 call #-32036 ;#0x82dc
    81ea: 0f 4c           mov r12, r15 ;
    81ec: 82 4c 0a 02 mov r12, &0x020a ;
dispLED(varc);

    81f0: b0 12 7a 81 call #-32390 ;#0x817a


                
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