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Match ASM comment spacing to 1.1.x

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This commit is contained in:
Scott Lahteine 2018-06-27 17:26:37 -05:00
parent 053438a3aa
commit 4d3a9930c5
1 changed files with 130 additions and 130 deletions
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260
Marlin/src/module/planner.cpp
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@ -386,89 +386,89 @@ void Planner::init() {
// use Newton-Raphson for the calculation, and will strive to get way less cycles // use Newton-Raphson for the calculation, and will strive to get way less cycles
// for the same result - Using C division, it takes 500cycles to complete . // for the same result - Using C division, it takes 500cycles to complete .
A("clr %3") // idx = 0 A("clr %3") // idx = 0
A("mov %14,%6") A("mov %14,%6")
A("mov %15,%7") A("mov %15,%7")
A("mov %16,%8") // nr = interval A("mov %16,%8") // nr = interval
A("tst %16") // nr & 0xFF0000 == 0 ? A("tst %16") // nr & 0xFF0000 == 0 ?
A("brne 2f") // No, skip this A("brne 2f") // No, skip this
A("mov %16,%15") A("mov %16,%15")
A("mov %15,%14") // nr <<= 8, %14 not needed A("mov %15,%14") // nr <<= 8, %14 not needed
A("subi %3,-8") // idx += 8 A("subi %3,-8") // idx += 8
A("tst %16") // nr & 0xFF0000 == 0 ? A("tst %16") // nr & 0xFF0000 == 0 ?
A("brne 2f") // No, skip this A("brne 2f") // No, skip this
A("mov %16,%15") // nr <<= 8, %14 not needed A("mov %16,%15") // nr <<= 8, %14 not needed
A("clr %15") // We clear %14 A("clr %15") // We clear %14
A("subi %3,-8") // idx += 8 A("subi %3,-8") // idx += 8
// here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0 // here %16 != 0 and %16:%15 contains at least 9 MSBits, or both %16:%15 are 0
L("2") L("2")
A("cpi %16,0x10") // (nr & 0xF00000) == 0 ? A("cpi %16,0x10") // (nr & 0xF00000) == 0 ?
A("brcc 3f") // No, skip this A("brcc 3f") // No, skip this
A("swap %15") // Swap nibbles A("swap %15") // Swap nibbles
A("swap %16") // Swap nibbles. Low nibble is 0 A("swap %16") // Swap nibbles. Low nibble is 0
A("mov %14, %15") A("mov %14, %15")
A("andi %14,0x0F") // Isolate low nibble A("andi %14,0x0F") // Isolate low nibble
A("andi %15,0xF0") // Keep proper nibble in %15 A("andi %15,0xF0") // Keep proper nibble in %15
A("or %16, %14") // %16:%15 <<= 4 A("or %16, %14") // %16:%15 <<= 4
A("subi %3,-4") // idx += 4 A("subi %3,-4") // idx += 4
L("3") L("3")
A("cpi %16,0x40") // (nr & 0xC00000) == 0 ? A("cpi %16,0x40") // (nr & 0xC00000) == 0 ?
A("brcc 4f") // No, skip this A("brcc 4f") // No, skip this
A("add %15,%15") A("add %15,%15")
A("adc %16,%16") A("adc %16,%16")
A("add %15,%15") A("add %15,%15")
A("adc %16,%16") // %16:%15 <<= 2 A("adc %16,%16") // %16:%15 <<= 2
A("subi %3,-2") // idx += 2 A("subi %3,-2") // idx += 2
L("4") L("4")
A("cpi %16,0x80") // (nr & 0x800000) == 0 ? A("cpi %16,0x80") // (nr & 0x800000) == 0 ?
A("brcc 5f") // No, skip this A("brcc 5f") // No, skip this
A("add %15,%15") A("add %15,%15")
A("adc %16,%16") // %16:%15 <<= 1 A("adc %16,%16") // %16:%15 <<= 1
A("inc %3") // idx += 1 A("inc %3") // idx += 1
// Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure // Now %16:%15 contains its MSBit set to 1, or %16:%15 is == 0. We are now absolutely sure
// we have at least 9 MSBits available to enter the initial estimation table // we have at least 9 MSBits available to enter the initial estimation table
L("5") L("5")
A("add %15,%15") A("add %15,%15")
A("adc %16,%16") // %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table) A("adc %16,%16") // %16:%15 = tidx = (nr <<= 1), we lose the top MSBit (always set to 1, %16 is the index into the inverse table)
A("add r30,%16") // Only use top 8 bits A("add r30,%16") // Only use top 8 bits
A("adc r31,%13") // r31:r30 = inv_tab + (tidx) A("adc r31,%13") // r31:r30 = inv_tab + (tidx)
A("lpm %14, Z") // %14 = inv_tab[tidx] A("lpm %14, Z") // %14 = inv_tab[tidx]
A("ldi %15, 1") // %15 = 1 %15:%14 = inv_tab[tidx] + 256 A("ldi %15, 1") // %15 = 1 %15:%14 = inv_tab[tidx] + 256
// We must scale the approximation to the proper place // We must scale the approximation to the proper place
A("clr %16") // %16 will always be 0 here A("clr %16") // %16 will always be 0 here
A("subi %3,8") // idx == 8 ? A("subi %3,8") // idx == 8 ?
A("breq 6f") // yes, no need to scale A("breq 6f") // yes, no need to scale
A("brcs 7f") // If C=1, means idx < 8, result was negative! A("brcs 7f") // If C=1, means idx < 8, result was negative!
// idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8] // idx > 8, now %3 = idx - 8. We must perform a left shift. idx range:[1-8]
A("sbrs %3,0") // shift by 1bit position? A("sbrs %3,0") // shift by 1bit position?
A("rjmp 8f") // No A("rjmp 8f") // No
A("add %14,%14") A("add %14,%14")
A("adc %15,%15") // %15:16 <<= 1 A("adc %15,%15") // %15:16 <<= 1
L("8") L("8")
A("sbrs %3,1") // shift by 2bit position? A("sbrs %3,1") // shift by 2bit position?
A("rjmp 9f") // No A("rjmp 9f") // No
A("add %14,%14") A("add %14,%14")
A("adc %15,%15") A("adc %15,%15")
A("add %14,%14") A("add %14,%14")
A("adc %15,%15") // %15:16 <<= 1 A("adc %15,%15") // %15:16 <<= 1
L("9") L("9")
A("sbrs %3,2") // shift by 4bits position? A("sbrs %3,2") // shift by 4bits position?
A("rjmp 16f") // No A("rjmp 16f") // No
A("swap %15") // Swap nibbles. lo nibble of %15 will always be 0 A("swap %15") // Swap nibbles. lo nibble of %15 will always be 0
A("swap %14") // Swap nibbles A("swap %14") // Swap nibbles
A("mov %12,%14") A("mov %12,%14")
A("andi %12,0x0F") // isolate low nibble A("andi %12,0x0F") // isolate low nibble
A("andi %14,0xF0") // and clear it A("andi %14,0xF0") // and clear it
A("or %15,%12") // %15:%16 <<= 4 A("or %15,%12") // %15:%16 <<= 4
L("16") L("16")
A("sbrs %3,3") // shift by 8bits position? A("sbrs %3,3") // shift by 8bits position?
A("rjmp 6f") // No, we are done A("rjmp 6f") // No, we are done
A("mov %16,%15") A("mov %16,%15")
A("mov %15,%14") A("mov %15,%14")
A("clr %14") A("clr %14")
@ -476,32 +476,32 @@ void Planner::init() {
// idx < 8, now %3 = idx - 8. Get the count of bits // idx < 8, now %3 = idx - 8. Get the count of bits
L("7") L("7")
A("neg %3") // %3 = -idx = count of bits to move right. idx range:[1...8] A("neg %3") // %3 = -idx = count of bits to move right. idx range:[1...8]
A("sbrs %3,0") // shift by 1 bit position ? A("sbrs %3,0") // shift by 1 bit position ?
A("rjmp 10f") // No, skip it A("rjmp 10f") // No, skip it
A("asr %15") // (bit7 is always 0 here) A("asr %15") // (bit7 is always 0 here)
A("ror %14") A("ror %14")
L("10") L("10")
A("sbrs %3,1") // shift by 2 bit position ? A("sbrs %3,1") // shift by 2 bit position ?
A("rjmp 11f") // No, skip it A("rjmp 11f") // No, skip it
A("asr %15") // (bit7 is always 0 here) A("asr %15") // (bit7 is always 0 here)
A("ror %14") A("ror %14")
A("asr %15") // (bit7 is always 0 here) A("asr %15") // (bit7 is always 0 here)
A("ror %14") A("ror %14")
L("11") L("11")
A("sbrs %3,2") // shift by 4 bit position ? A("sbrs %3,2") // shift by 4 bit position ?
A("rjmp 12f") // No, skip it A("rjmp 12f") // No, skip it
A("swap %15") // Swap nibbles A("swap %15") // Swap nibbles
A("andi %14, 0xF0") // Lose the lowest nibble A("andi %14, 0xF0") // Lose the lowest nibble
A("swap %14") // Swap nibbles. Upper nibble is 0 A("swap %14") // Swap nibbles. Upper nibble is 0
A("or %14,%15") // Pass nibble from upper byte A("or %14,%15") // Pass nibble from upper byte
A("andi %15, 0x0F") // And get rid of that nibble A("andi %15, 0x0F") // And get rid of that nibble
L("12") L("12")
A("sbrs %3,3") // shift by 8 bit position ? A("sbrs %3,3") // shift by 8 bit position ?
A("rjmp 6f") // No, skip it A("rjmp 6f") // No, skip it
A("mov %14,%15") A("mov %14,%15")
A("clr %15") A("clr %15")
L("6") // %16:%15:%14 = initial estimation of 0x1000000 / d L("6") // %16:%15:%14 = initial estimation of 0x1000000 / d
// Now, we must refine the estimation present on %16:%15:%14 using 1 iteration // Now, we must refine the estimation present on %16:%15:%14 using 1 iteration
// of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough // of Newton-Raphson. As it has a quadratic convergence, 1 iteration is enough
@ -517,33 +517,33 @@ void Planner::init() {
A("clr %0") A("clr %0")
A("clr %1") A("clr %1")
A("clr %2") A("clr %2")
A("ldi %3,2") // %3:%2:%1:%0 = 0x2000000 A("ldi %3,2") // %3:%2:%1:%0 = 0x2000000
A("mul %6,%14") // r1:r0 = LO(d) * LO(x) A("mul %6,%14") // r1:r0 = LO(d) * LO(x)
A("sub %0,r0") A("sub %0,r0")
A("sbc %1,r1") A("sbc %1,r1")
A("sbc %2,%13") A("sbc %2,%13")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * LO(x) A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * LO(x)
A("mul %7,%14") // r1:r0 = MI(d) * LO(x) A("mul %7,%14") // r1:r0 = MI(d) * LO(x)
A("sub %1,r0") A("sub %1,r0")
A("sbc %2,r1" ) A("sbc %2,r1" )
A("sbc %3,%13") // %3:%2:%1:%0 -= MI(d) * LO(x) << 8 A("sbc %3,%13") // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
A("mul %8,%14") // r1:r0 = HI(d) * LO(x) A("mul %8,%14") // r1:r0 = HI(d) * LO(x)
A("sub %2,r0") A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16 A("sbc %3,r1") // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
A("mul %6,%15") // r1:r0 = LO(d) * MI(x) A("mul %6,%15") // r1:r0 = LO(d) * MI(x)
A("sub %1,r0") A("sub %1,r0")
A("sbc %2,r1") A("sbc %2,r1")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * MI(x) << 8 A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
A("mul %7,%15") // r1:r0 = MI(d) * MI(x) A("mul %7,%15") // r1:r0 = MI(d) * MI(x)
A("sub %2,r0") A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MI(d) * MI(x) << 16 A("sbc %3,r1") // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
A("mul %8,%15") // r1:r0 = HI(d) * MI(x) A("mul %8,%15") // r1:r0 = HI(d) * MI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24 A("sub %3,r0") // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
A("mul %6,%16") // r1:r0 = LO(d) * HI(x) A("mul %6,%16") // r1:r0 = LO(d) * HI(x)
A("sub %2,r0") A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= LO(d) * HI(x) << 16 A("sbc %3,r1") // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
A("mul %7,%16") // r1:r0 = MI(d) * HI(x) A("mul %7,%16") // r1:r0 = MI(d) * HI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MI(d) * HI(x) << 24 A("sub %3,r0") // %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
@ -553,62 +553,62 @@ void Planner::init() {
// %13 = 0 // %13 = 0
// result = %11:%10:%9:%5:%4 // result = %11:%10:%9:%5:%4
A("mul %14,%0") // r1:r0 = LO(x) * LO(acc) A("mul %14,%0") // r1:r0 = LO(x) * LO(acc)
A("mov %4,r1") A("mov %4,r1")
A("clr %5") A("clr %5")
A("clr %9") A("clr %9")
A("clr %10") A("clr %10")
A("clr %11") // %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8 A("clr %11") // %11:%10:%9:%5:%4 = LO(x) * LO(acc) >> 8
A("mul %15,%0") // r1:r0 = MI(x) * LO(acc) A("mul %15,%0") // r1:r0 = MI(x) * LO(acc)
A("add %4,r0") A("add %4,r0")
A("adc %5,r1") A("adc %5,r1")
A("adc %9,%13") A("adc %9,%13")
A("adc %10,%13") A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * LO(acc) A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * LO(acc)
A("mul %16,%0") // r1:r0 = HI(x) * LO(acc) A("mul %16,%0") // r1:r0 = HI(x) * LO(acc)
A("add %5,r0") A("add %5,r0")
A("adc %9,r1") A("adc %9,r1")
A("adc %10,%13") A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8 A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * LO(acc) << 8
A("mul %14,%1") // r1:r0 = LO(x) * MIL(acc) A("mul %14,%1") // r1:r0 = LO(x) * MIL(acc)
A("add %4,r0") A("add %4,r0")
A("adc %5,r1") A("adc %5,r1")
A("adc %9,%13") A("adc %9,%13")
A("adc %10,%13") A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * MIL(acc) A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * MIL(acc)
A("mul %15,%1") // r1:r0 = MI(x) * MIL(acc) A("mul %15,%1") // r1:r0 = MI(x) * MIL(acc)
A("add %5,r0") A("add %5,r0")
A("adc %9,r1") A("adc %9,r1")
A("adc %10,%13") A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8 A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 8
A("mul %16,%1") // r1:r0 = HI(x) * MIL(acc) A("mul %16,%1") // r1:r0 = HI(x) * MIL(acc)
A("add %9,r0") A("add %9,r0")
A("adc %10,r1") A("adc %10,r1")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16 A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIL(acc) << 16
A("mul %14,%2") // r1:r0 = LO(x) * MIH(acc) A("mul %14,%2") // r1:r0 = LO(x) * MIH(acc)
A("add %5,r0") A("add %5,r0")
A("adc %9,r1") A("adc %9,r1")
A("adc %10,%13") A("adc %10,%13")
A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8 A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * MIH(acc) << 8
A("mul %15,%2") // r1:r0 = MI(x) * MIH(acc) A("mul %15,%2") // r1:r0 = MI(x) * MIH(acc)
A("add %9,r0") A("add %9,r0")
A("adc %10,r1") A("adc %10,r1")
A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16 A("adc %11,%13") // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 16
A("mul %16,%2") // r1:r0 = HI(x) * MIH(acc) A("mul %16,%2") // r1:r0 = HI(x) * MIH(acc)
A("add %10,r0") A("add %10,r0")
A("adc %11,r1") // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24 A("adc %11,r1") // %11:%10:%9:%5:%4 += MI(x) * MIH(acc) << 24
A("mul %14,%3") // r1:r0 = LO(x) * HI(acc) A("mul %14,%3") // r1:r0 = LO(x) * HI(acc)
A("add %9,r0") A("add %9,r0")
A("adc %10,r1") A("adc %10,r1")
A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16 A("adc %11,%13") // %11:%10:%9:%5:%4 = LO(x) * HI(acc) << 16
A("mul %15,%3") // r1:r0 = MI(x) * HI(acc) A("mul %15,%3") // r1:r0 = MI(x) * HI(acc)
A("add %10,r0") A("add %10,r0")
A("adc %11,r1") // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24 A("adc %11,r1") // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 24
A("mul %16,%3") // r1:r0 = HI(x) * HI(acc) A("mul %16,%3") // r1:r0 = HI(x) * HI(acc)
A("add %11,r0") // %11:%10:%9:%5:%4 += MI(x) * HI(acc) << 32 A("add %11,r0") // %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.
@ -619,47 +619,47 @@ void Planner::init() {
A("ldi %3,1") A("ldi %3,1")
A("clr %2") A("clr %2")
A("clr %1") A("clr %1")
A("clr %0") // %3:%2:%1:%0 = 0x1000000 A("clr %0") // %3:%2:%1:%0 = 0x1000000
A("mul %6,%9") // r1:r0 = LO(d) * LO(x) A("mul %6,%9") // r1:r0 = LO(d) * LO(x)
A("sub %0,r0") A("sub %0,r0")
A("sbc %1,r1") A("sbc %1,r1")
A("sbc %2,%13") A("sbc %2,%13")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * LO(x) A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * LO(x)
A("mul %7,%9") // r1:r0 = MI(d) * LO(x) A("mul %7,%9") // r1:r0 = MI(d) * LO(x)
A("sub %1,r0") A("sub %1,r0")
A("sbc %2,r1") A("sbc %2,r1")
A("sbc %3,%13") // %3:%2:%1:%0 -= MI(d) * LO(x) << 8 A("sbc %3,%13") // %3:%2:%1:%0 -= MI(d) * LO(x) << 8
A("mul %8,%9") // r1:r0 = HI(d) * LO(x) A("mul %8,%9") // r1:r0 = HI(d) * LO(x)
A("sub %2,r0") A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16 A("sbc %3,r1") // %3:%2:%1:%0 -= MIL(d) * LO(x) << 16
A("mul %6,%10") // r1:r0 = LO(d) * MI(x) A("mul %6,%10") // r1:r0 = LO(d) * MI(x)
A("sub %1,r0") A("sub %1,r0")
A("sbc %2,r1") A("sbc %2,r1")
A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * MI(x) << 8 A("sbc %3,%13") // %3:%2:%1:%0 -= LO(d) * MI(x) << 8
A("mul %7,%10") // r1:r0 = MI(d) * MI(x) A("mul %7,%10") // r1:r0 = MI(d) * MI(x)
A("sub %2,r0") A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= MI(d) * MI(x) << 16 A("sbc %3,r1") // %3:%2:%1:%0 -= MI(d) * MI(x) << 16
A("mul %8,%10") // r1:r0 = HI(d) * MI(x) A("mul %8,%10") // r1:r0 = HI(d) * MI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24 A("sub %3,r0") // %3:%2:%1:%0 -= MIL(d) * MI(x) << 24
A("mul %6,%11") // r1:r0 = LO(d) * HI(x) A("mul %6,%11") // r1:r0 = LO(d) * HI(x)
A("sub %2,r0") A("sub %2,r0")
A("sbc %3,r1") // %3:%2:%1:%0 -= LO(d) * HI(x) << 16 A("sbc %3,r1") // %3:%2:%1:%0 -= LO(d) * HI(x) << 16
A("mul %7,%11") // r1:r0 = MI(d) * HI(x) A("mul %7,%11") // r1:r0 = MI(d) * HI(x)
A("sub %3,r0") // %3:%2:%1:%0 -= MI(d) * HI(x) << 24 A("sub %3,r0") // %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
A("sub %0,%6") A("sub %0,%6")
A("sbc %1,%7") A("sbc %1,%7")
A("sbc %2,%8") // r -= d A("sbc %2,%8") // r -= d
A("brcs 14f") // if ( r >= d) A("brcs 14f") // if ( r >= d)
// %11:%10:%9 = x // %11:%10:%9 = x
A("ldi %3,1") A("ldi %3,1")
A("add %9,%3") A("add %9,%3")
A("adc %10,%13") A("adc %10,%13")
A("adc %11,%13") // x++ A("adc %11,%13") // x++
L("14") L("14")
// Estimation is done. %11:%10:%9 = x // Estimation is done. %11:%10:%9 = x