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@ -406,300 +406,300 @@ void Planner::init() { |
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register const uint8_t* ptab = inv_tab; |
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register const uint8_t* ptab = inv_tab; |
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__asm__ __volatile__( |
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__asm__ __volatile__( |
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/* %8:%7:%6 = interval*/ |
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// %8:%7:%6 = interval
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/* r31:r30: MUST be those registers, and they must point to the inv_tab */ |
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// r31:r30: MUST be those registers, and they must point to the inv_tab
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" clr %13" "\n\t" /* %13 = 0 */ |
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" clr %13" "\n\t" // %13 = 0
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/* Now we must compute */ |
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// Now we must compute
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/* result = 0xFFFFFF / d */ |
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// result = 0xFFFFFF / d
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/* %8:%7:%6 = interval*/ |
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// %8:%7:%6 = interval
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/* %16:%15:%14 = nr */ |
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// %16:%15:%14 = nr
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/* %13 = 0*/ |
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// %13 = 0
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/* A plain division of 24x24 bits should take 388 cycles to complete. We will */ |
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// A plain division of 24x24 bits should take 388 cycles to complete. We will
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/* use Newton-Raphson for the calculation, and will strive to get way less cycles*/ |
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// use Newton-Raphson for the calculation, and will strive to get way less cycles
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/* for the same result - Using C division, it takes 500cycles to complete .*/ |
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// for the same result - Using C division, it takes 500cycles to complete .
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" clr %3" "\n\t" /* idx = 0 */ |
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" clr %3" "\n\t" // idx = 0
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" mov %14,%6" "\n\t" |
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" mov %14,%6" "\n\t" |
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" mov %15,%7" "\n\t" |
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" mov %15,%7" "\n\t" |
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" mov %16,%8" "\n\t" /* nr = interval */ |
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" mov %16,%8" "\n\t" // nr = interval
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" tst %16" "\n\t" /* nr & 0xFF0000 == 0 ? */ |
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" tst %16" "\n\t" // nr & 0xFF0000 == 0 ?
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" brne 2f" "\n\t" /* No, skip this */ |
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" brne 2f" "\n\t" // No, skip this
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" mov %16,%15" "\n\t" |
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" mov %16,%15" "\n\t" |
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" mov %15,%14" "\n\t" /* nr <<= 8, %14 not needed */ |
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" mov %15,%14" "\n\t" // nr <<= 8, %14 not needed
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" subi %3,-8" "\n\t" /* idx += 8 */ |
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" subi %3,-8" "\n\t" // idx += 8
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" tst %16" "\n\t" /* nr & 0xFF0000 == 0 ? */ |
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" tst %16" "\n\t" // nr & 0xFF0000 == 0 ?
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" brne 2f" "\n\t" /* No, skip this */ |
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" brne 2f" "\n\t" // No, skip this
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" mov %16,%15" "\n\t" /* nr <<= 8, %14 not needed */ |
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" mov %16,%15" "\n\t" // nr <<= 8, %14 not needed
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" clr %15" "\n\t" /* We clear %14 */ |
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" clr %15" "\n\t" // We clear %14
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" subi %3,-8" "\n\t" /* idx += 8 */ |
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" subi %3,-8" "\n\t" // idx += 8
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/* here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0 */ |
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// here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0
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"2:" "\n\t" |
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"2:" "\n\t" |
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" cpi %16,0x10" "\n\t" /* (nr & 0xf00000) == 0 ? */ |
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" cpi %16,0x10" "\n\t" // (nr & 0xf00000) == 0 ?
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" brcc 3f" "\n\t" /* No, skip this */ |
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" brcc 3f" "\n\t" // No, skip this
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" swap %15" "\n\t" /* Swap nibbles */ |
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" swap %15" "\n\t" // Swap nibbles
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" swap %16" "\n\t" /* Swap nibbles. Low nibble is 0 */ |
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" swap %16" "\n\t" // Swap nibbles. Low nibble is 0
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" mov %14, %15" "\n\t" |
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" mov %14, %15" "\n\t" |
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" andi %14,0x0f" "\n\t" /* Isolate low nibble */ |
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" andi %14,0x0f" "\n\t" // Isolate low nibble
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" andi %15,0xf0" "\n\t" /* Keep proper nibble in %15 */ |
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" andi %15,0xf0" "\n\t" // Keep proper nibble in %15
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" or %16, %14" "\n\t" /* %16:%15 <<= 4 */ |
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" or %16, %14" "\n\t" // %16:%15 <<= 4
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" subi %3,-4" "\n\t" /* idx += 4 */ |
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" subi %3,-4" "\n\t" // idx += 4
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"3:" "\n\t" |
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"3:" "\n\t" |
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" cpi %16,0x40" "\n\t" /* (nr & 0xc00000) == 0 ? */ |
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" cpi %16,0x40" "\n\t" // (nr & 0xc00000) == 0 ?
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" brcc 4f" "\n\t" /* No, skip this*/ |
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" brcc 4f" "\n\t" // No, skip this
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" add %15,%15" "\n\t" |
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" add %15,%15" "\n\t" |
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" adc %16,%16" "\n\t" |
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" adc %16,%16" "\n\t" |
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" add %15,%15" "\n\t" |
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" add %15,%15" "\n\t" |
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" adc %16,%16" "\n\t" /* %16:%15 <<= 2 */ |
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" adc %16,%16" "\n\t" // %16:%15 <<= 2
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" subi %3,-2" "\n\t" /* idx += 2 */ |
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" subi %3,-2" "\n\t" // idx += 2
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"4:" "\n\t" |
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"4:" "\n\t" |
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" cpi %16,0x80" "\n\t" /* (nr & 0x800000) == 0 ? */ |
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" cpi %16,0x80" "\n\t" // (nr & 0x800000) == 0 ?
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" brcc 5f" "\n\t" /* No, skip this */ |
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" brcc 5f" "\n\t" // No, skip this
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" add %15,%15" "\n\t" |
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" add %15,%15" "\n\t" |
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" adc %16,%16" "\n\t" /* %16:%15 <<= 1 */ |
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" adc %16,%16" "\n\t" // %16:%15 <<= 1
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" inc %3" "\n\t" /* idx += 1 */ |
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" inc %3" "\n\t" // idx += 1
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/* Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure*/ |
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// Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure
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/* we have at least 9 MSBits available to enter the initial estimation table*/ |
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// we have at least 9 MSBits available to enter the initial estimation table
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"5:" "\n\t" |
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"5:" "\n\t" |
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" add %15,%15" "\n\t" |
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" add %15,%15" "\n\t" |
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" adc %16,%16" "\n\t" /* %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table)*/ |
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" adc %16,%16" "\n\t" // %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table)
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" add r30,%16" "\n\t" /* Only use top 8 bits */ |
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" add r30,%16" "\n\t" // Only use top 8 bits
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" adc r31,%13" "\n\t" /* r31:r30 = inv_tab + (tidx) */ |
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" adc r31,%13" "\n\t" // r31:r30 = inv_tab + (tidx)
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" lpm %14, Z" "\n\t" /* %14 = inv_tab[tidx] */ |
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" lpm %14, Z" "\n\t" // %14 = inv_tab[tidx]
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" ldi %15, 1" "\n\t" /* %15 = 1 %15:%14 = inv_tab[tidx] + 256 */ |
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" ldi %15, 1" "\n\t" // %15 = 1 %15:%14 = inv_tab[tidx] + 256
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/* We must scale the approximation to the proper place*/ |
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// We must scale the approximation to the proper place
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" clr %16" "\n\t" /* %16 will always be 0 here */ |
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" clr %16" "\n\t" // %16 will always be 0 here
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" subi %3,8" "\n\t" /* idx == 8 ? */ |
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" subi %3,8" "\n\t" // idx == 8 ?
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" breq 6f" "\n\t" /* yes, no need to scale*/ |
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" breq 6f" "\n\t" // yes, no need to scale
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" brcs 7f" "\n\t" /* If C=1, means idx < 8, result was negative!*/ |
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" brcs 7f" "\n\t" // If C=1, means idx < 8, result was negative!
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/* idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8]*/ |
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// idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8]
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" sbrs %3,0" "\n\t" /* shift by 1bit position?*/ |
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" sbrs %3,0" "\n\t" // shift by 1bit position?
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" rjmp 8f" "\n\t" /* No*/ |
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" rjmp 8f" "\n\t" // No
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" add %14,%14" "\n\t" |
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" add %14,%14" "\n\t" |
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" adc %15,%15" "\n\t" /* %15:16 <<= 1*/ |
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" adc %15,%15" "\n\t" // %15:16 <<= 1
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"8:" "\n\t" |
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"8:" "\n\t" |
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" sbrs %3,1" "\n\t" /* shift by 2bit position?*/ |
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" sbrs %3,1" "\n\t" // shift by 2bit position?
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" rjmp 9f" "\n\t" /* No*/ |
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" rjmp 9f" "\n\t" // No
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" add %14,%14" "\n\t" |
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" add %14,%14" "\n\t" |
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" adc %15,%15" "\n\t" |
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" adc %15,%15" "\n\t" |
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" add %14,%14" "\n\t" |
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" add %14,%14" "\n\t" |
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" adc %15,%15" "\n\t" /* %15:16 <<= 1*/ |
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" adc %15,%15" "\n\t" // %15:16 <<= 1
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"9:" "\n\t" |
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"9:" "\n\t" |
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" sbrs %3,2" "\n\t" /* shift by 4bits position?*/ |
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" sbrs %3,2" "\n\t" // shift by 4bits position?
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" rjmp 16f" "\n\t" /* No*/ |
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" rjmp 16f" "\n\t" // No
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" swap %15" "\n\t" /* Swap nibbles. lo nibble of %15 will always be 0*/ |
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" swap %15" "\n\t" // Swap nibbles. lo nibble of %15 will always be 0
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" swap %14" "\n\t" /* Swap nibbles*/ |
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" swap %14" "\n\t" // Swap nibbles
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" mov %12,%14" "\n\t" |
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" mov %12,%14" "\n\t" |
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" andi %12,0x0f" "\n\t" /* isolate low nibble*/ |
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" andi %12,0x0f" "\n\t" // isolate low nibble
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" andi %14,0xf0" "\n\t" /* and clear it*/ |
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" andi %14,0xf0" "\n\t" // and clear it
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" or %15,%12" "\n\t" /* %15:%16 <<= 4*/ |
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" or %15,%12" "\n\t" // %15:%16 <<= 4
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"16:" "\n\t" |
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"16:" "\n\t" |
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" sbrs %3,3" "\n\t" /* shift by 8bits position?*/ |
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" sbrs %3,3" "\n\t" // shift by 8bits position?
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" rjmp 6f" "\n\t" /* No, we are done */ |
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" rjmp 6f" "\n\t" // No, we are done
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" mov %16,%15" "\n\t" |
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" mov %16,%15" "\n\t" |
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" mov %15,%14" "\n\t" |
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" mov %15,%14" "\n\t" |
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" clr %14" "\n\t" |
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" clr %14" "\n\t" |
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" jmp 6f" "\n\t" |
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" jmp 6f" "\n\t" |
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/* idx < 8, now %3 = idx - 8. Get the count of bits */ |
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// idx < 8, now %3 = idx - 8. Get the count of bits
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"7:" "\n\t" |
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"7:" "\n\t" |
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" neg %3" "\n\t" /* %3 = -idx = count of bits to move right. idx range:[1...8]*/ |
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" neg %3" "\n\t" // %3 = -idx = count of bits to move right. idx range:[1...8]
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" sbrs %3,0" "\n\t" /* shift by 1 bit position ?*/ |
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" sbrs %3,0" "\n\t" // shift by 1 bit position ?
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" rjmp 10f" "\n\t" /* No, skip it*/ |
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" rjmp 10f" "\n\t" // No, skip it
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" asr %15" "\n\t" /* (bit7 is always 0 here)*/ |
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" asr %15" "\n\t" // (bit7 is always 0 here)
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" ror %14" "\n\t" |
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" ror %14" "\n\t" |
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"10:" "\n\t" |
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"10:" "\n\t" |
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" sbrs %3,1" "\n\t" /* shift by 2 bit position ?*/ |
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" sbrs %3,1" "\n\t" // shift by 2 bit position ?
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" rjmp 11f" "\n\t" /* No, skip it*/ |
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" rjmp 11f" "\n\t" // No, skip it
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" asr %15" "\n\t" /* (bit7 is always 0 here)*/ |
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" asr %15" "\n\t" // (bit7 is always 0 here)
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" ror %14" "\n\t" |
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" ror %14" "\n\t" |
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" asr %15" "\n\t" /* (bit7 is always 0 here)*/ |
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" asr %15" "\n\t" // (bit7 is always 0 here)
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" ror %14" "\n\t" |
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" ror %14" "\n\t" |
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"11:" "\n\t" |
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"11:" "\n\t" |
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" sbrs %3,2" "\n\t" /* shift by 4 bit position ?*/ |
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" sbrs %3,2" "\n\t" // shift by 4 bit position ?
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" rjmp 12f" "\n\t" /* No, skip it*/ |
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" rjmp 12f" "\n\t" // No, skip it
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" swap %15" "\n\t" /* Swap nibbles*/ |
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" swap %15" "\n\t" // Swap nibbles
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" andi %14, 0xf0" "\n\t" /* Lose the lowest nibble*/ |
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" andi %14, 0xf0" "\n\t" // Lose the lowest nibble
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" swap %14" "\n\t" /* Swap nibbles. Upper nibble is 0*/ |
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" swap %14" "\n\t" // Swap nibbles. Upper nibble is 0
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" or %14,%15" "\n\t" /* Pass nibble from upper byte*/ |
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" or %14,%15" "\n\t" // Pass nibble from upper byte
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" andi %15, 0x0f" "\n\t" /* And get rid of that nibble*/ |
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" andi %15, 0x0f" "\n\t" // And get rid of that nibble
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"12:" "\n\t" |
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"12:" "\n\t" |
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" sbrs %3,3" "\n\t" /* shift by 8 bit position ?*/ |
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" sbrs %3,3" "\n\t" // shift by 8 bit position ?
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" rjmp 6f" "\n\t" /* No, skip it*/ |
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" rjmp 6f" "\n\t" // No, skip it
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" mov %14,%15" "\n\t" |
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" mov %14,%15" "\n\t" |
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" clr %15" "\n\t" |
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" clr %15" "\n\t" |
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"6:" "\n\t" /* %16:%15:%14 = initial estimation of 0x1000000 / d*/ |
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"6:" "\n\t" // %16:%15:%14 = initial estimation of 0x1000000 / d
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/* Now, we must refine the estimation present on %16:%15:%14 using 1 iteration*/ |
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// Now, we must refine the estimation present on %16:%15:%14 using 1 iteration
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/* of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough*/ |
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// of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough
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/* to get more than 18bits of precision (the initial table lookup gives 9 bits of*/ |
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// to get more than 18bits of precision (the initial table lookup gives 9 bits of
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/* precision to start from). 18bits of precision is all what is needed here for result */ |
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// precision to start from). 18bits of precision is all what is needed here for result
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/* %8:%7:%6 = d = interval*/ |
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// %8:%7:%6 = d = interval
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/* %16:%15:%14 = x = initial estimation of 0x1000000 / d*/ |
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// %16:%15:%14 = x = initial estimation of 0x1000000 / d
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/* %13 = 0*/ |
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// %13 = 0
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/* %3:%2:%1:%0 = working accumulator*/ |
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// %3:%2:%1:%0 = working accumulator
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/* Compute 1<<25 - x*d. Result should never exceed 25 bits and should always be positive*/ |
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// Compute 1<<25 - x*d. Result should never exceed 25 bits and should always be positive
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" clr %0" "\n\t" |
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" clr %0" "\n\t" |
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" clr %1" "\n\t" |
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" clr %1" "\n\t" |
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" clr %2" "\n\t" |
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" clr %2" "\n\t" |
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" ldi %3,2" "\n\t" /* %3:%2:%1:%0 = 0x2000000*/ |
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" ldi %3,2" "\n\t" // %3:%2:%1:%0 = 0x2000000
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" mul %6,%14" "\n\t" /* r1:r0 = LO(d) * LO(x)*/ |
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" mul %6,%14" "\n\t" // r1:r0 = LO(d) * LO(x)
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" sub %0,r0" "\n\t" |
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" sub %0,r0" "\n\t" |
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" sbc %1,r1" "\n\t" |
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" sbc %1,r1" "\n\t" |
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" sbc %2,%13" "\n\t" |
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" sbc %2,%13" "\n\t" |
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" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * LO(x)*/ |
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" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * LO(x)
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" mul %7,%14" "\n\t" /* r1:r0 = MI(d) * LO(x)*/ |
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" mul %7,%14" "\n\t" // r1:r0 = MI(d) * LO(x)
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" sub %1,r0" "\n\t" |
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" sub %1,r0" "\n\t" |
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" sbc %2,r1" "\n\t" |
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" sbc %2,r1" "\n\t" |
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" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= MI(d) * LO(x) << 8*/ |
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" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
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" mul %8,%14" "\n\t" /* r1:r0 = HI(d) * LO(x)*/ |
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" mul %8,%14" "\n\t" // r1:r0 = HI(d) * LO(x)
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" sub %2,r0" "\n\t" |
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" sub %2,r0" "\n\t" |
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" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * LO(x) << 16*/ |
|
|
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
|
|
|
" mul %6,%15" "\n\t" /* r1:r0 = LO(d) * MI(x)*/ |
|
|
" mul %6,%15" "\n\t" // r1:r0 = LO(d) * MI(x)
|
|
|
" sub %1,r0" "\n\t" |
|
|
" sub %1,r0" "\n\t" |
|
|
" sbc %2,r1" "\n\t" |
|
|
" sbc %2,r1" "\n\t" |
|
|
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * MI(x) << 8*/ |
|
|
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
|
|
|
" mul %7,%15" "\n\t" /* r1:r0 = MI(d) * MI(x)*/ |
|
|
" mul %7,%15" "\n\t" // r1:r0 = MI(d) * MI(x)
|
|
|
" sub %2,r0" "\n\t" |
|
|
" sub %2,r0" "\n\t" |
|
|
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MI(d) * MI(x) << 16*/ |
|
|
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
|
|
|
" mul %8,%15" "\n\t" /* r1:r0 = HI(d) * MI(x)*/ |
|
|
" mul %8,%15" "\n\t" // r1:r0 = HI(d) * MI(x)
|
|
|
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * MI(x) << 24*/ |
|
|
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
|
|
|
" mul %6,%16" "\n\t" /* r1:r0 = LO(d) * HI(x)*/ |
|
|
" mul %6,%16" "\n\t" // r1:r0 = LO(d) * HI(x)
|
|
|
" sub %2,r0" "\n\t" |
|
|
" sub %2,r0" "\n\t" |
|
|
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= LO(d) * HI(x) << 16*/ |
|
|
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
|
|
|
" mul %7,%16" "\n\t" /* r1:r0 = MI(d) * HI(x)*/ |
|
|
" mul %7,%16" "\n\t" // r1:r0 = MI(d) * HI(x)
|
|
|
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MI(d) * HI(x) << 24*/ |
|
|
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MI(d) * HI(x) << 24
|
|
|
/* %3:%2:%1:%0 = (1<<25) - x*d [169]*/ |
|
|
// %3:%2:%1:%0 = (1<<25) - x*d [169]
|
|
|
|
|
|
|
|
|
/* We need to multiply that result by x, and we are only interested in the top 24bits of that multiply*/ |
|
|
// We need to multiply that result by x, and we are only interested in the top 24bits of that multiply
|
|
|
|
|
|
|
|
|
/* %16:%15:%14 = x = initial estimation of 0x1000000 / d*/ |
|
|
// %16:%15:%14 = x = initial estimation of 0x1000000 / d
|
|
|
/* %3:%2:%1:%0 = (1<<25) - x*d = acc*/ |
|
|
// %3:%2:%1:%0 = (1<<25) - x*d = acc
|
|
|
/* %13 = 0 */ |
|
|
// %13 = 0
|
|
|
|
|
|
|
|
|
/* result = %11:%10:%9:%5:%4*/ |
|
|
// result = %11:%10:%9:%5:%4
|
|
|
" mul %14,%0" "\n\t" /* r1:r0 = LO(x) * LO(acc)*/ |
|
|
" mul %14,%0" "\n\t" // r1:r0 = LO(x) * LO(acc)
|
|
|
" mov %4,r1" "\n\t" |
|
|
" mov %4,r1" "\n\t" |
|
|
" clr %5" "\n\t" |
|
|
" clr %5" "\n\t" |
|
|
" clr %9" "\n\t" |
|
|
" clr %9" "\n\t" |
|
|
" clr %10" "\n\t" |
|
|
" clr %10" "\n\t" |
|
|
" clr %11" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8*/ |
|
|
" clr %11" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8
|
|
|
" mul %15,%0" "\n\t" /* r1:r0 = MI(x) * LO(acc)*/ |
|
|
" mul %15,%0" "\n\t" // r1:r0 = MI(x) * LO(acc)
|
|
|
" add %4,r0" "\n\t" |
|
|
" add %4,r0" "\n\t" |
|
|
" adc %5,r1" "\n\t" |
|
|
" adc %5,r1" "\n\t" |
|
|
" adc %9,%13" "\n\t" |
|
|
" adc %9,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * LO(acc) */ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * LO(acc)
|
|
|
" mul %16,%0" "\n\t" /* r1:r0 = HI(x) * LO(acc)*/ |
|
|
" mul %16,%0" "\n\t" // r1:r0 = HI(x) * LO(acc)
|
|
|
" add %5,r0" "\n\t" |
|
|
" add %5,r0" "\n\t" |
|
|
" adc %9,r1" "\n\t" |
|
|
" adc %9,r1" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8
|
|
|
|
|
|
|
|
|
" mul %14,%1" "\n\t" /* r1:r0 = LO(x) * MIL(acc)*/ |
|
|
" mul %14,%1" "\n\t" // r1:r0 = LO(x) * MIL(acc)
|
|
|
" add %4,r0" "\n\t" |
|
|
" add %4,r0" "\n\t" |
|
|
" adc %5,r1" "\n\t" |
|
|
" adc %5,r1" "\n\t" |
|
|
" adc %9,%13" "\n\t" |
|
|
" adc %9,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * MIL(acc)*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * MIL(acc)
|
|
|
" mul %15,%1" "\n\t" /* r1:r0 = MI(x) * MIL(acc)*/ |
|
|
" mul %15,%1" "\n\t" // r1:r0 = MI(x) * MIL(acc)
|
|
|
" add %5,r0" "\n\t" |
|
|
" add %5,r0" "\n\t" |
|
|
" adc %9,r1" "\n\t" |
|
|
" adc %9,r1" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8
|
|
|
" mul %16,%1" "\n\t" /* r1:r0 = HI(x) * MIL(acc)*/ |
|
|
" mul %16,%1" "\n\t" // r1:r0 = HI(x) * MIL(acc)
|
|
|
" add %9,r0" "\n\t" |
|
|
" add %9,r0" "\n\t" |
|
|
" adc %10,r1" "\n\t" |
|
|
" adc %10,r1" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16
|
|
|
|
|
|
|
|
|
" mul %14,%2" "\n\t" /* r1:r0 = LO(x) * MIH(acc)*/ |
|
|
" mul %14,%2" "\n\t" // r1:r0 = LO(x) * MIH(acc)
|
|
|
" add %5,r0" "\n\t" |
|
|
" add %5,r0" "\n\t" |
|
|
" adc %9,r1" "\n\t" |
|
|
" adc %9,r1" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8
|
|
|
" mul %15,%2" "\n\t" /* r1:r0 = MI(x) * MIH(acc)*/ |
|
|
" mul %15,%2" "\n\t" // r1:r0 = MI(x) * MIH(acc)
|
|
|
" add %9,r0" "\n\t" |
|
|
" add %9,r0" "\n\t" |
|
|
" adc %10,r1" "\n\t" |
|
|
" adc %10,r1" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16
|
|
|
" mul %16,%2" "\n\t" /* r1:r0 = HI(x) * MIH(acc)*/ |
|
|
" mul %16,%2" "\n\t" // r1:r0 = HI(x) * MIH(acc)
|
|
|
" add %10,r0" "\n\t" |
|
|
" add %10,r0" "\n\t" |
|
|
" adc %11,r1" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24*/ |
|
|
" adc %11,r1" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24
|
|
|
|
|
|
|
|
|
" mul %14,%3" "\n\t" /* r1:r0 = LO(x) * HI(acc)*/ |
|
|
" mul %14,%3" "\n\t" // r1:r0 = LO(x) * HI(acc)
|
|
|
" add %9,r0" "\n\t" |
|
|
" add %9,r0" "\n\t" |
|
|
" adc %10,r1" "\n\t" |
|
|
" adc %10,r1" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16*/ |
|
|
" adc %11,%13" "\n\t" // %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16
|
|
|
" mul %15,%3" "\n\t" /* r1:r0 = MI(x) * HI(acc)*/ |
|
|
" mul %15,%3" "\n\t" // r1:r0 = MI(x) * HI(acc)
|
|
|
" add %10,r0" "\n\t" |
|
|
" add %10,r0" "\n\t" |
|
|
" adc %11,r1" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24*/ |
|
|
" adc %11,r1" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24
|
|
|
" mul %16,%3" "\n\t" /* r1:r0 = HI(x) * HI(acc)*/ |
|
|
" mul %16,%3" "\n\t" // r1:r0 = HI(x) * HI(acc)
|
|
|
" add %11,r0" "\n\t" /* %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 32*/ |
|
|
" add %11,r0" "\n\t" // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 32
|
|
|
|
|
|
|
|
|
/* At this point, %11:%10:%9 contains the new estimation of x. */ |
|
|
// At this point, %11:%10:%9 contains the new estimation of x.
|
|
|
|
|
|
|
|
|
/* Finally, we must correct the result. Estimate remainder as*/ |
|
|
// Finally, we must correct the result. Estimate remainder as
|
|
|
/* (1<<24) - x*d*/ |
|
|
// (1<<24) - x*d
|
|
|
/* %11:%10:%9 = x*/ |
|
|
// %11:%10:%9 = x
|
|
|
/* %8:%7:%6 = d = interval" "\n\t" /* */ |
|
|
// %8:%7:%6 = d = interval" "\n\t"
|
|
|
" ldi %3,1" "\n\t" |
|
|
" ldi %3,1" "\n\t" |
|
|
" clr %2" "\n\t" |
|
|
" clr %2" "\n\t" |
|
|
" clr %1" "\n\t" |
|
|
" clr %1" "\n\t" |
|
|
" clr %0" "\n\t" /* %3:%2:%1:%0 = 0x1000000*/ |
|
|
" clr %0" "\n\t" // %3:%2:%1:%0 = 0x1000000
|
|
|
" mul %6,%9" "\n\t" /* r1:r0 = LO(d) * LO(x)*/ |
|
|
" mul %6,%9" "\n\t" // r1:r0 = LO(d) * LO(x)
|
|
|
" sub %0,r0" "\n\t" |
|
|
" sub %0,r0" "\n\t" |
|
|
" sbc %1,r1" "\n\t" |
|
|
" sbc %1,r1" "\n\t" |
|
|
" sbc %2,%13" "\n\t" |
|
|
" sbc %2,%13" "\n\t" |
|
|
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * LO(x)*/ |
|
|
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * LO(x)
|
|
|
" mul %7,%9" "\n\t" /* r1:r0 = MI(d) * LO(x)*/ |
|
|
" mul %7,%9" "\n\t" // r1:r0 = MI(d) * LO(x)
|
|
|
" sub %1,r0" "\n\t" |
|
|
" sub %1,r0" "\n\t" |
|
|
" sbc %2,r1" "\n\t" |
|
|
" sbc %2,r1" "\n\t" |
|
|
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= MI(d) * LO(x) << 8*/ |
|
|
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
|
|
|
" mul %8,%9" "\n\t" /* r1:r0 = HI(d) * LO(x)*/ |
|
|
" mul %8,%9" "\n\t" // r1:r0 = HI(d) * LO(x)
|
|
|
" sub %2,r0" "\n\t" |
|
|
" sub %2,r0" "\n\t" |
|
|
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * LO(x) << 16*/ |
|
|
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
|
|
|
" mul %6,%10" "\n\t" /* r1:r0 = LO(d) * MI(x)*/ |
|
|
" mul %6,%10" "\n\t" // r1:r0 = LO(d) * MI(x)
|
|
|
" sub %1,r0" "\n\t" |
|
|
" sub %1,r0" "\n\t" |
|
|
" sbc %2,r1" "\n\t" |
|
|
" sbc %2,r1" "\n\t" |
|
|
" sbc %3,%13" "\n\t" /* %3:%2:%1:%0 -= LO(d) * MI(x) << 8*/ |
|
|
" sbc %3,%13" "\n\t" // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
|
|
|
" mul %7,%10" "\n\t" /* r1:r0 = MI(d) * MI(x)*/ |
|
|
" mul %7,%10" "\n\t" // r1:r0 = MI(d) * MI(x)
|
|
|
" sub %2,r0" "\n\t" |
|
|
" sub %2,r0" "\n\t" |
|
|
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= MI(d) * MI(x) << 16*/ |
|
|
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
|
|
|
" mul %8,%10" "\n\t" /* r1:r0 = HI(d) * MI(x)*/ |
|
|
" mul %8,%10" "\n\t" // r1:r0 = HI(d) * MI(x)
|
|
|
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MIL(d) * MI(x) << 24*/ |
|
|
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
|
|
|
" mul %6,%11" "\n\t" /* r1:r0 = LO(d) * HI(x)*/ |
|
|
" mul %6,%11" "\n\t" // r1:r0 = LO(d) * HI(x)
|
|
|
" sub %2,r0" "\n\t" |
|
|
" sub %2,r0" "\n\t" |
|
|
" sbc %3,r1" "\n\t" /* %3:%2:%1:%0 -= LO(d) * HI(x) << 16*/ |
|
|
" sbc %3,r1" "\n\t" // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
|
|
|
" mul %7,%11" "\n\t" /* r1:r0 = MI(d) * HI(x)*/ |
|
|
" mul %7,%11" "\n\t" // r1:r0 = MI(d) * HI(x)
|
|
|
" sub %3,r0" "\n\t" /* %3:%2:%1:%0 -= MI(d) * HI(x) << 24*/ |
|
|
" sub %3,r0" "\n\t" // %3:%2:%1:%0 -= MI(d) * HI(x) << 24
|
|
|
/* %3:%2:%1:%0 = r = (1<<24) - x*d*/ |
|
|
// %3:%2:%1:%0 = r = (1<<24) - x*d
|
|
|
/* %8:%7:%6 = d = interval */ |
|
|
// %8:%7:%6 = d = interval
|
|
|
|
|
|
|
|
|
/* Perform the final correction*/ |
|
|
// Perform the final correction
|
|
|
" sub %0,%6" "\n\t" |
|
|
" sub %0,%6" "\n\t" |
|
|
" sbc %1,%7" "\n\t" |
|
|
" sbc %1,%7" "\n\t" |
|
|
" sbc %2,%8" "\n\t" /* r -= d*/ |
|
|
" sbc %2,%8" "\n\t" // r -= d
|
|
|
" brcs 14f" "\n\t" /* if ( r >= d) */ |
|
|
" brcs 14f" "\n\t" // if ( r >= d)
|
|
|
|
|
|
|
|
|
/* %11:%10:%9 = x */ |
|
|
// %11:%10:%9 = x
|
|
|
" ldi %3,1" "\n\t" |
|
|
" ldi %3,1" "\n\t" |
|
|
" add %9,%3" "\n\t" |
|
|
" add %9,%3" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %10,%13" "\n\t" |
|
|
" adc %11,%13" "\n\t" /* x++*/ |
|
|
" adc %11,%13" "\n\t" // x++
|
|
|
"14:" "\n\t" |
|
|
"14:" "\n\t" |
|
|
|
|
|
|
|
|
/* Estimation is done. %11:%10:%9 = x */ |
|
|
// Estimation is done. %11:%10:%9 = x
|
|
|
" clr __zero_reg__" "\n\t" /* Make C runtime happy */ |
|
|
" clr __zero_reg__" "\n\t" // Make C runtime happy
|
|
|
/* [211 cycles total]*/ |
|
|
// [211 cycles total]
|
|
|
: "=r" (r2), |
|
|
: "=r" (r2), |
|
|
"=r" (r3), |
|
|
"=r" (r3), |
|
|
"=r" (r4), |
|
|
"=r" (r4), |
|
|