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QEMU doesn't implement ARMv4/v5 legacy SCTLR.U==0 load-and-rotate unaligned access handling
Description of problem:
**ldr r7, \[r0, r1\]** works differently on real device and QEMU. Probably all **ldr Rd, \[Rs\]** commands works wrongly in QEMU with Raspberry Pi emulation.
Steps to reproduce:
1. Launch the attached software **kernel_qemu.img** in QEMU.
2. Launch the attached software **kerenel.img** on real Raspberry Pi 1B+.
3. Look at the r7. It contains different data.
Additional information:
**kernel_qemu.img** and **kerenel.img** are the same program. It just compiled with different origins - 0x8000 for real device and 0x10000 for QEMU. But code inside the program works at the same addresses.
r0 = 0x183a4
r1 = 0x817
**\[r0, r1\]** points to byte 0x42 in memory with such data:
**0x80 0x15 0x22 \[0x42\] 0x03 0x21 0x87**
After **ldr r7, \[r0, r1\]** execution real device puts to r7: **0x22158042**
After **ldr r7, \[r0, r1\]** execution QEMU puts to r7: **0x87210342**
QEMU:
Real Raspberry Pi 1B+: 
[kernel_qemu.img](/uploads/ae6a7490660569d5fe56adc9f4dde85d/kernel_qemu.img) [kernel.img](/uploads/48c94a66370c1fe8720fe89603c45c7b/kernel.img)
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