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A few micro-optimizations in the 6502 emulation (found by cppcheck).

This commit is contained in:
Stephen Anthony 2018-08-27 12:17:22 -02:30
parent 8c7488914d
commit c901f282bb
2 changed files with 18 additions and 18 deletions
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24
src/emucore/M6502.ins
View File

@ -616,10 +616,10 @@ case 0x4b:
// Set carry flag according to the right-most bit
C = A & 0x01;
A = (A >> 1) & 0x7f;
A >>= 1;
notZ = A;
N = A & 0x80;
N = 0;
}
break;
@ -2671,10 +2671,10 @@ case 0x4a:
// Set carry flag according to the right-most bit
C = A & 0x01;
A = (A >> 1) & 0x7f;
A >>= 1;
notZ = A;
N = A & 0x80;
N = 0;
}
break;
@ -2689,11 +2689,11 @@ case 0x46:
// Set carry flag according to the right-most bit in value
C = operand & 0x01;
operand = (operand >> 1) & 0x7f;
operand >>= 1;
poke(operandAddress, operand, DISASM_WRITE);
notZ = operand;
N = operand & 0x80;
N = 0;
}
break;
@ -2709,11 +2709,11 @@ case 0x56:
// Set carry flag according to the right-most bit in value
C = operand & 0x01;
operand = (operand >> 1) & 0x7f;
operand >>= 1;
poke(operandAddress, operand, DISASM_WRITE);
notZ = operand;
N = operand & 0x80;
N = 0;
}
break;
@ -2728,11 +2728,11 @@ case 0x4e:
// Set carry flag according to the right-most bit in value
C = operand & 0x01;
operand = (operand >> 1) & 0x7f;
operand >>= 1;
poke(operandAddress, operand, DISASM_WRITE);
notZ = operand;
N = operand & 0x80;
N = 0;
}
break;
@ -2749,11 +2749,11 @@ case 0x5e:
// Set carry flag according to the right-most bit in value
C = operand & 0x01;
operand = (operand >> 1) & 0x7f;
operand >>= 1;
poke(operandAddress, operand, DISASM_WRITE);
notZ = operand;
N = operand & 0x80;
N = 0;
}
break;

12
src/emucore/M6502.m4
View File

@ -482,10 +482,10 @@ define(M6502_ASR, `{
// Set carry flag according to the right-most bit
C = A & 0x01;
A = (A >> 1) & 0x7f;
A >>= 1;
notZ = A;
N = A & 0x80;
N = 0;
}')
define(M6502_BIT, `{
@ -691,21 +691,21 @@ define(M6502_LSR, `{
// Set carry flag according to the right-most bit in value
C = operand & 0x01;
operand = (operand >> 1) & 0x7f;
operand >>= 1;
poke(operandAddress, operand, DISASM_WRITE);
notZ = operand;
N = operand & 0x80;
N = 0;
}')
define(M6502_LSRA, `{
// Set carry flag according to the right-most bit
C = A & 0x01;
A = (A >> 1) & 0x7f;
A >>= 1;
notZ = A;
N = A & 0x80;
N = 0;
}')
define(M6502_LXA, `{