[PATCH v3] RISC-V: Introduce gcc attribute riscv_rvv_vector_bits for RVV

[Li, Pan2]

> The result of comparison should be vbool* rather than v[u]int*.
> The result of comparison should be vbool* rather than vfloat*,
> otherwise all 1 is not really meanful for floating point value.

> But I know clang generates the same strange/wrong code here...

I see, will update the test cases and double check about it in v4.

> &, ^, | has supported on clang, so I think we should support that as well

Looks gcc lack of such operation right now, so mark the TYPE_INDIVISIBLE_P (type) = 0 as aarch64 did.
I have a try but I am afraid we need separated patch to take care of it for risk control consideration.

Pan

-----Original Message-----
From: Kito Cheng <kito.cheng@gmail.com> 
Sent: Thursday, March 21, 2024 9:25 PM
To: Li, Pan2 <pan2.li@intel.com>
Cc: gcc-patches@gcc.gnu.org; juzhe.zhong@rivai.ai; Wang, Yanzhang <yanzhang.wang@intel.com>; rdapp.gcc@gmail.com; vineetg@rivosinc.com; palmer@rivosinc.com
Subject: Re: [PATCH v3] RISC-V: Introduce gcc attribute riscv_rvv_vector_bits for RVV

> For the vint*m*_t below operations are allowed.
> * The sizeof.
> * The global variable(s).
> * The element of union and struct.
> * The cast to other equalities.
> * CMP: >, <, ==, !=, <=, >=

The result of comparison should be vbool* rather than v[u]int*.

> * ALU: +, -, *, /, %, &, |, ^, >>, <<, ~, -
>
> For the vfloat*m*_t below operations are allowed.
> * The sizeof.
> * The global variable(s).
> * The element of union and struct.
> * The cast to other equalities.
> * CMP: >, <, ==, !=, <=, >=

The result of comparison should be vbool* rather than vfloat*,
otherwise all 1 is not really meanful for floating point value.

But I know clang generates the same strange/wrong code here...

> * ALU: +, -, *, /, -
>
> For the vbool*_t types only below operations are allowed except
> the CMP and ALU. The CMP and ALU operations on vbool*_t is not
> well defined currently.
> * The sizeof.
> * The global variable(s).
> * The element of union and struct.
> * The cast to other equalities.

&, ^, | has supported on clang, so I think we should support that as well