34 lines
708 B
Go
34 lines
708 B
Go
package x86
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import "git.akyoto.dev/cli/q/src/cpu"
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// memoryAccess encodes a memory access.
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func memoryAccess(code []byte, opCode8 byte, opCode32 byte, register cpu.Register, offset int8, numBytes byte, source cpu.Register) []byte {
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opCode := opCode32
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if numBytes == 1 {
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opCode = opCode8
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}
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mod := AddressMemory
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if offset != 0 || register == RBP || register == R13 {
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mod = AddressMemoryOffset8
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}
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if numBytes == 2 {
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code = append(code, 0x66)
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}
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code = encode(code, mod, source, register, numBytes, opCode)
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if register == RSP || register == R12 {
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code = append(code, SIB(Scale1, 0b100, 0b100))
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}
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if mod == AddressMemoryOffset8 {
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code = append(code, byte(offset))
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}
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return code
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}
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