[Mesa-dev] [PATCH 1/1] ac/nir: use ordered float comparisons except for not equal

[Timothy Arceri]

Using this on its own I believe will cause CTS regressions, which is 
what the other patches were about. Feel free to take on the feedback and 
come up with a proper solution. I'm not really sure how to progress this.


On 24/02/18 00:21, Samuel Pitoiset wrote:
> Original patch from Timothy Arceri, I have just fixed the
> not equal case locally.
> 
> This fixes one important rendering issue in Wolfenstein 2
> (the cutscene transition issue).
> 
> RadeonSI uses the same ordered comparisons, so I guess that
> what we should do as well.
> 
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104302
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=104905
> Cc: <mesa-stable at lists.freedesktop.org>
> Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
> ---
>   src/amd/common/ac_nir_to_llvm.c | 6 +++---
>   1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
> index cccc687157..bc1d16d2a4 100644
> --- a/src/amd/common/ac_nir_to_llvm.c
> +++ b/src/amd/common/ac_nir_to_llvm.c
> @@ -1801,16 +1801,16 @@ static void visit_alu(struct ac_nir_context *ctx, const nir_alu_instr *instr)
>   		result = emit_int_cmp(&ctx->ac, LLVMIntUGE, src[0], src[1]);
>   		break;
>   	case nir_op_feq:
> -		result = emit_float_cmp(&ctx->ac, LLVMRealUEQ, src[0], src[1]);
> +		result = emit_float_cmp(&ctx->ac, LLVMRealOEQ, src[0], src[1]);
>   		break;
>   	case nir_op_fne:
>   		result = emit_float_cmp(&ctx->ac, LLVMRealUNE, src[0], src[1]);
>   		break;
>   	case nir_op_flt:
> -		result = emit_float_cmp(&ctx->ac, LLVMRealULT, src[0], src[1]);
> +		result = emit_float_cmp(&ctx->ac, LLVMRealOLT, src[0], src[1]);
>   		break;
>   	case nir_op_fge:
> -		result = emit_float_cmp(&ctx->ac, LLVMRealUGE, src[0], src[1]);
> +		result = emit_float_cmp(&ctx->ac, LLVMRealOGE, src[0], src[1]);
>   		break;
>   	case nir_op_fabs:
>   		result = emit_intrin_1f_param(&ctx->ac, "llvm.fabs",
>