[PATCH] RISC-V: Enable overlap-by-pieces in case of fast unaliged access
Vineet Gupta
vineetg@rivosinc.com
Tue Nov 2 20:15:12 GMT 2021
On 11/2/21 1:09 PM, Christoph Müllner wrote:
>>>> Without overlap_op_by_pieces we get:
>>>> 8e: 00053023 sd zero,0(a0)
>>>> 92: 00052423 sw zero,8(a0)
>>>> 96: 00051623 sh zero,12(a0)
>>>> 9a: 00050723 sb zero,14(a0)
>> To generate even the non optimized code above with gcc 11 [1][2], what
>> do I need to do. Despite -mno-strict-align and trying -mtune={rocket,
>> sifive-7-series}, I only get the fully unrolled version
> You need a tuning struct with slow_unaligned_access == false.
> Both, Rocket and Sifive 7, have slow unaligned access set to true.
> Mainline you have thead-c906 which would work.
But doesn't -mno-strict-align imply that ?
Thx,
-Vineet
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