29 lines
824 B
C++
29 lines
824 B
C++
//: operating directly on a register
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:(scenario add_r32_to_r32)
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% Reg[0].i = 0x10;
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% Reg[3].i = 1;
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# op ModR/M SIB displacement immediate
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01 d8 # add EBX (reg 3) to EAX (reg 0)
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+run: add reg 3 to effective address
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+run: effective address is reg 0
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+run: storing 0x00000011
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:(before "End Mod Special-cases")
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case 3:
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// mod 3 is just register direct addressing
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trace(2, "run") << "effective address is reg " << NUM(rm) << end();
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result = &Reg[rm].i;
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break;
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//:: subtract
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:(scenario subtract_r32_from_r32)
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% Reg[0].i = 10;
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% Reg[3].i = 1;
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# op ModR/M SIB displacement immediate
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29 d8 # subtract EBX (reg 3) from EAX (reg 0)
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+run: subtract reg 3 from effective address
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+run: effective address is reg 0
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+run: storing 0x00000009
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