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Fixed 8-bit XCHG instruction on the 64-bit old recompiler when both source and destination are a high 8-bit register (AH, CH, BH, or DH), fixes the longstanding Chicago 58s bug.

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This commit is contained in:
OBattler
2020-12-12 15:59:10 +01:00
parent 09bc3d6cd0
commit a55b9c6512
2 changed files with 18 additions and 29 deletions
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43
src/codegen/codegen_ops_x86-64.h
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@@ -297,33 +297,26 @@ static inline void STORE_REG_TARGET_B_RELEASE(int host_reg, int guest_reg)
addbyte(0x44);
addbyte(0x89);
addbyte(0xc0 | ((host_reg & 3) << 3));
if (host_reg & 0x10)
{
addbyte(0x66); /*AND AX, 0xff00*/
addbyte(0x25);
addword(0xff00);
}
else
{
addbyte(0x66); /*SHL AX, 8*/
addbyte(0xc1);
addbyte(0xe0);
addbyte(0x08);
}
}
else
{
if (host_reg)
{
addbyte(0x66); /*MOV AX, host_reg*/
addbyte(0x89);
addbyte(0xc0 | ((host_reg & 3) << 3));
}
addbyte(0x66); /*SHL AX, 8*/
addbyte(0xc1);
addbyte(0xe0);
addbyte(0x08);
else if (host_reg & 3)
{
addbyte(0x66); /*MOV AX, host_reg*/
addbyte(0x89);
addbyte(0xc0 | ((host_reg & 3) << 3));
}
if (host_reg & 0x10)
{
addbyte(0x66); /*AND AX, 0xff00*/
addbyte(0x25);
addword(0xff00);
}
else
{
addbyte(0x66); /*SHL AX, 8*/
addbyte(0xc1);
addbyte(0xe0);
addbyte(0x08);
}
addbyte(0x66); /*AND dest_reg, 0x00ff*/
addbyte(0x41);
addbyte(0x81);