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213c90d3c1
Trying to populate the recently added test for GetInstructionSize I
stumbled over this.
gdb and bddisasm have the opinion this instruction is 9 bytes.
Also lldb shows this:
```
(lldb) disassemble --bytes --start-address 0x0000555555556004 --end-address 0x0000555555556024
0x555555556004: 41 81 7b 73 74 75 76 77 cmpl $0x77767574, 0x73(%r11) ; imm = 0x77767574
0x55555555600c: 41 81 7c 73 74 75 76 77 78 cmpl $0x78777675, 0x74(%r11,%rsi,2) ; imm = 0x78777675
0x555555556015: 41 81 7d 73 74 75 76 77 cmpl $0x77767574, 0x73(%r13) ; imm = 0x77767574
0x55555555601d: 00 00 addb %al, (%rax)
```
There is also a handy tool in llvm to directly feed in the byte sequence
- `41 81 7c` also uses 9 bytes here:
```
$ echo -n -e "0x41, 0x81, 0x7b, 0x73, 0x74, 0x75, 0x76, 0x77, 0x90" | ./llvm/build/bin/llvm-mc --disassemble --show-encoding
.text
cmpl $2004252020, 115(%r11) # encoding: [0x41,0x81,0x7b,0x73,0x74,0x75,0x76,0x77]
# imm = 0x77767574
nop # encoding: [0x90]
$ echo -n -e "0x41, 0x81, 0x7c, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x90" | ./llvm/build/bin/llvm-mc --disassemble --show-encoding
.text
cmpl $2021095029, 116(%r11,%rsi,2) # encoding: [0x41,0x81,0x7c,0x73,0x74,0x75,0x76,0x77,0x78]
# imm = 0x78777675
nop # encoding: [0x90]
```
Compiler-RT ================================ This directory and its subdirectories contain source code for the compiler support routines. Compiler-RT is open source software. You may freely distribute it under the terms of the license agreement found in LICENSE.txt. ================================