[llvm-dev] Is this a bug or is llvm processing conservative?

[Panyuntao(Compiler) via llvm-dev]

Hi, All developers:

I have this code. For (*b)[2], It is reasonable that llvm thinks it's unaligned access. and I think the array pointer always points to 4 - byte aligned array elements.

[cid:image001.png at 01D61C07.2E95DB10]
CMD: clang  --target=arm-none-eabi -mcpu=cortex-r52 -mthumb -O0 -emit-llvm -S test.c -o test.ll
LLVM think it's an align 1 store, I don't think so.
[cid:image002.png at 01D61C08.6DC76AF0]
CMD: llc -mattr=+strict-align test.ll
If the CPU does not support non-aligned access, The access is divided into four one-byte access.

[cid:image003.png at 01D61C09.E2D82DB0]
CMD: llc -mattr=-strict-align test.ll
If the CPU support non-aligned access, It's a normal four-byte access.
[cid:image004.png at 01D61C0A.F65032B0]

But gcc always think it's an aligned access ,and processed him as a four-byte access. I think this is reasonable.
CMD1: arm-none-eabi-gcc -mcpu=cortex-r52 -mthumb  -munaligned-access -O0 -emit-llvm -S test.c -o test.s
CMD2: arm-none-eabi-gcc -mcpu=cortex-r52 -mthumb  -mno-unaligned-access -O0 -emit-llvm -S test.c -o test.s
[cid:image005.png at 01D61C0B.34493800]

Why does LLVM think it's a one-byte-aligned access? I think it makes more sense to access the number of aligned based on the type of the array element to which the array pointer points
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