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@pranith pranith commented Mar 4, 2021

Several of the special versions of POP such as POPDS, POPSS, etc list the operand as ignore instead of write. Pull request capstone-engine#1725 corrects the issue.

Actual cstool output for POPDS (note missing WRITE on operand[0]):
./cstool -d x32 "1f"
0 1f pop ds
Prefix:0x00 0x00 0x00 0x00
Opcode:0x1f 0x00 0x00 0x00
rex: 0x0
addr_size: 4
modrm: 0x0
disp: 0x0
sib: 0x0
op_count: 1
operands[0].type: REG = ds
operands[0].size: 2
Groups: privilege not64bitmode

Expected output from cstool for POPDS (note inclusion of WRITE on operand[0]):
./cstool -d x32 "1f"
0 1f pop ds
Prefix:0x00 0x00 0x00 0x00
Opcode:0x1f 0x00 0x00 0x00
rex: 0x0
addr_size: 4
modrm: 0x0
disp: 0x0
sib: 0x0
op_count: 1
operands[0].type: REG = ds
operands[0].size: 2
operands[0].access: WRITE
Registers modified: ds
Groups: privilege not64bitmode

Re-fix operand access of three mov instructions
The python script for generating constants in the bindings does not know how to handle the #if 0 statements included in these files.
Pulling from upstream
Registry access for the destination operand of the conditional move (cmov) opcodes were incorrectly listed as READ | WRITE. Although you would expect the two operands to be compared in this opcode, it instead relies on the associated flag in EFLAGS regardless of the value in the destination operand.
@pranith pranith closed this Mar 4, 2021
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