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UNDEFINED case for instruction BLX
Hi
I refer to the instruction BLX imm (T2 encoding) in ARMv7 (Thumb mode).
11110 S imm10H 11 J1 0 J2 imm10L H
if H == '1' then UNDEFINED;
I1 = NOT(J1 EOR S); I2 = NOT(J2 EOR S); imm32 = SignExtend(S:I1:I2:imm10H:imm10L:'00', 32);
targetInstrSet = InstrSet_A32;
if InITBlock() && !LastInITBlock() then UNPREDICTABLE;
According to the manual, if H equals to 1, this instruction should be an UNDEFINED instruction. However, it seems QEMU does not check this constraint in function trans_BLX_i. Thanks
Regards
Muhui
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