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Eliminate nibble macros.

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Thomas Harte 2024-10-09 21:04:32 -04:00
parent 95fac5dc13
commit 4838728521
1 changed files with 11 additions and 13 deletions
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20
InstructionSets/M50740/Executor.cpp
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@ -724,16 +724,15 @@ template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_u
uint16_t partials = 0; uint16_t partials = 0;
int result = carry_flag_; int result = carry_flag_;
#define nibble(mask, limit, adjustment, carry) \ const auto nibble = [&](uint16_t mask, uint16_t limit, uint16_t adjustment, uint16_t carry) {
result += (a & mask) + (*operand & mask); \ result += (a & mask) + (*operand & mask);
partials += result & mask; \ partials += result & mask;
if(result >= limit) result = ((result + (adjustment)) & (carry - 1)) + carry; if(result >= limit) result = ((result + (adjustment)) & (carry - 1)) + carry;
};
nibble(0x000f, 0x000a, 0x0006, 0x00010); nibble(0x000f, 0x000a, 0x0006, 0x00010);
nibble(0x00f0, 0x00a0, 0x0060, 0x00100); nibble(0x00f0, 0x00a0, 0x0060, 0x00100);
#undef nibble
overflow_result_ = uint8_t((partials ^ a) & (partials ^ *operand)); overflow_result_ = uint8_t((partials ^ a) & (partials ^ *operand));
set_nz(uint8_t(result)); set_nz(uint8_t(result));
carry_flag_ = (result >> 8) & 1; carry_flag_ = (result >> 8) & 1;
@ -742,17 +741,16 @@ template <Operation operation> void Executor::perform(uint8_t *operand [[maybe_u
unsigned int borrow = carry_flag_ ^ 1; unsigned int borrow = carry_flag_ ^ 1;
const uint16_t decimal_result = uint16_t(a - *operand - borrow); const uint16_t decimal_result = uint16_t(a - *operand - borrow);
#define nibble(mask, adjustment, carry) \ const auto nibble = [&](uint16_t mask, uint16_t adjustment, uint16_t carry) {
result += (a & mask) - (*operand & mask) - borrow; \ result += (a & mask) - (*operand & mask) - borrow;
if(result > mask) result -= adjustment; \ if(result > mask) result -= adjustment;
borrow = (result > mask) ? carry : 0; \ borrow = (result > mask) ? carry : 0;
result &= (carry - 1); result &= (carry - 1);
};
nibble(0x000f, 0x0006, 0x00010); nibble(0x000f, 0x0006, 0x00010);
nibble(0x00f0, 0x0060, 0x00100); nibble(0x00f0, 0x0060, 0x00100);
#undef nibble
overflow_result_ = uint8_t((decimal_result ^ a) & (~decimal_result ^ *operand)); overflow_result_ = uint8_t((decimal_result ^ a) & (~decimal_result ^ *operand));
set_nz(uint8_t(result)); set_nz(uint8_t(result));
carry_flag_ = ((borrow >> 8)&1)^1; carry_flag_ = ((borrow >> 8)&1)^1;