Hi,
I was half asleep when I reported my last code generation problem, but
this time I think I am awake :-)
The attached test.c file compiles to the attached test.s file. There
seems to be something rather wrong with this. The arithmetic performed
on accum2 looks OK, but accum1 is screwed up. accum1 is never loaded or
stored, and screwy registers are used in accumulating the result of the
imul16 routine.
Regards,
Steve
#include <signal.h>
#include <io.h>
int32_t static __inline__ imul16(register int16_t x, register int16_t y)
{
register int32_t z;
__asm__ (
"__MPY=0x130 \n"
"__MPYS=0x132 \n"
"__MAC=0x134 \n"
"__MACS=0x136 \n"
"__OP2=0x138 \n"
"__RESLO=0x13a \n"
"__RESHI=0x13c \n"
"__SUMEXT=0x13e \n"
" mov %1,&__MPYS \n"
" mov %2,&__OP2 \n"
" mov &__RESHI,%B0 \n"
" mov &__RESLO,%A0 \n"
: "=r"(z)
: "r"(x), "r"(y));
return z;
}
int32_t accum1;
int32_t accum2;
interrupt (TIMERB0_VECTOR) adc_interrupt(void)
{
int16_t sampleA;
int16_t sampleB;
sampleA = ADC12MEM[0];
sampleB = ADC12MEM[1];
accum1 += imul16(sampleA, sampleB);
accum2 += imul16(sampleA, sampleA);
}
.file "test.c"
.arch msp430x149
/* Hardware multiplier registers: */
__MPY=0x130
__MPYS=0x132
__MAC=0x134
__MACS=0x136
__OP2=0x138
__RESLO=0x13a
__RESHI=0x13c
__SUMEXT=0x13e
.text
.p2align 1,0
.global adc_interrupt
.global vector_fffa
.type adc_interrupt,@function
/***********************
* Interrupt Service Routine `adc_interrupt' at 0xfffa
***********************/
vector_fffa:
adc_interrupt:
/* prologue: frame size = 0 */
.L__FrameSize_adc_interrupt=0x0
.L__FrameOffset_adc_interrupt=0x6
push r15
push r14
push r13
/* prologue end (size=3) */
mov &320, r13
mov &322, r15
/* #APP */
__MPY=0x130
__MPYS=0x132
__MAC=0x134
__MACS=0x136
__OP2=0x138
__RESLO=0x13a
__RESHI=0x13c
__SUMEXT=0x13e
mov r13,&__MPYS
mov r15,&__OP2
mov &__RESHI,r15
mov &__RESLO,r14
/* #NOAPP */
add r14, r14
addc r15, r15
/* #APP */
__MPY=0x130
__MPYS=0x132
__MAC=0x134
__MACS=0x136
__OP2=0x138
__RESLO=0x13a
__RESHI=0x13c
__SUMEXT=0x13e
mov r13,&__MPYS
mov r13,&__OP2
mov &__RESHI,r15
mov &__RESLO,r14
/* #NOAPP */
add r14, &accum2
addc r15, &accum2+2
/* epilogue: frame size=0 */
pop r13
pop r14
pop r15
reti
/* epilogue end (size=4) */
/* function adc_interrupt size 71 (64) */
.Lfe1:
.size adc_interrupt,.Lfe1-adc_interrupt
/********* End of function ******/
.comm accum1,4,2
.comm accum2,4,2
/*********************************************************************
* File test.c: code size: 71 words (0x47)
* incl. words in prologues: 3, epilogues: 4
*********************************************************************/
