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[aarch64] Enable Always and Never Branch patching for TBZ/TBNZ and CBZ/CBNZ #7281

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[aarch64] Enable Always and Never Branch patching for TBZ/TBNZ and CBZ/CBNZ #7281

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18 changes: 13 additions & 5 deletions arch/arm64/arch_arm64.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -1168,7 +1168,7 @@ class Arm64Architecture : public Architecture
Instruction instr;
if (!Disassemble(data, addr, len, instr))
return false;
return IsConditionalBranch(instr);
return IsConditionalJump(instr);
}


Expand All @@ -1177,7 +1177,7 @@ class Arm64Architecture : public Architecture
Instruction instr;
if (!Disassemble(data, addr, len, instr))
return false;
return IsConditionalBranch(instr);
return IsConditionalJump(instr);
}


Expand Down Expand Up @@ -1230,9 +1230,17 @@ class Arm64Architecture : public Architecture
return false;

uint32_t* value = (uint32_t*)data;
// Combine the immediate in the first operand with the unconditional branch opcode to form
// an unconditional branch instruction
*value = (5 << 26) | (((uint32_t)((instr.operands[0].immediate - addr) >> 2)) & 0x03ffffff);
if (IsConditionalBranch(instr))
{
// Combine the immediate in the first operand with the unconditional branch opcode to form
// an unconditional branch instruction
*value = (5 << 26) | (((uint32_t)((instr.operands[0].immediate - addr) >> 2)) & 0x03ffffff);
}
else
{
// Force to a *BZ, then change the register to zero register (WZR or XZR, determined by bit 31)
*value = (*value & ~(1 << 24)) | 0x0f;
}
return true;
}

Expand Down