[Mesa-dev] [Mesa-stable] [PATCH] ac/nir: Make the GFX9 buffer size fix apply to image loads/atomics too.

[Juan A. Suarez Romero]

On Mon, 2018-04-16 at 00:09 +0200, Bas Nieuwenhuizen wrote:
> No clue how I missed those ...
> 
> Fixes: 4503ff760c "ac/nir: Add workaround for GFX9 buffer views."
> CC: <mesa-stable at lists.freedesktop.org>
> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=105320


Hi, Bas!

This commit is a candidate for next 17.3 and 18.0 stable releases.


Regarding the next 17.3.9 release, which should be released today, as this is
the last one of 17.3, I understand you want this patch as part of the release,
right?

If that's the case, I cherry-picked the commit and solved some trivial
conflicts. You can check to verify I correctly solved them at:

https://github.com/Igalia/release-mesa/commit/37ad9fc7c6cecdb8a99d071ca6fdc2d663
7501a8


Related with that commit, maybe you want to ensure that this one also is
correct:

https://github.com/Igalia/release-mesa/commit/51b4bdc7761b30a56299ee80f51521151d
4eec47



Regarding the next 18.0.1, is it fine if we post-pone this patch for next
18.0.2, or do you think this must be added in 18.0.1?


	J.A.



> ---
>  src/amd/common/ac_nir_to_llvm.c | 39 +++++++++++++++++++--------------
>  1 file changed, 22 insertions(+), 17 deletions(-)
> 
> diff --git a/src/amd/common/ac_nir_to_llvm.c b/src/amd/common/ac_nir_to_llvm.c
> index 3a3aa72988..45405d30fe 100644
> --- a/src/amd/common/ac_nir_to_llvm.c
> +++ b/src/amd/common/ac_nir_to_llvm.c
> @@ -2191,6 +2191,25 @@ static LLVMValueRef get_image_coords(struct ac_nir_context *ctx,
>  	return res;
>  }
>  
> +static LLVMValueRef get_image_buffer_descriptor(struct ac_nir_context *ctx,
> +                                                const nir_intrinsic_instr *instr, bool write)
> +{
> +	LLVMValueRef rsrc = get_sampler_desc(ctx, instr->variables[0], AC_DESC_BUFFER, NULL, true, write);
> +	if (ctx->abi->gfx9_stride_size_workaround) {
> +		LLVMValueRef elem_count = LLVMBuildExtractElement(ctx->ac.builder, rsrc, LLVMConstInt(ctx->ac.i32, 2, 0), "");
> +		LLVMValueRef stride = LLVMBuildExtractElement(ctx->ac.builder, rsrc, LLVMConstInt(ctx->ac.i32, 1, 0), "");
> +		stride = LLVMBuildLShr(ctx->ac.builder, stride, LLVMConstInt(ctx->ac.i32, 16, 0), "");
> +
> +		LLVMValueRef new_elem_count = LLVMBuildSelect(ctx->ac.builder,
> +		                                              LLVMBuildICmp(ctx->ac.builder, LLVMIntUGT, elem_count, stride, ""),
> +		                                              elem_count, stride, "");
> +
> +		rsrc = LLVMBuildInsertElement(ctx->ac.builder, rsrc, new_elem_count,
> +		                              LLVMConstInt(ctx->ac.i32, 2, 0), "");
> +	}
> +	return rsrc;
> +}
> +
>  static LLVMValueRef visit_image_load(struct ac_nir_context *ctx,
>  				     const nir_intrinsic_instr *instr)
>  {
> @@ -2211,7 +2230,7 @@ static LLVMValueRef visit_image_load(struct ac_nir_context *ctx,
>  		unsigned num_channels = util_last_bit(mask);
>  		LLVMValueRef rsrc, vindex;
>  
> -		rsrc = get_sampler_desc(ctx, instr->variables[0], AC_DESC_BUFFER, NULL, true, false);
> +		rsrc = get_image_buffer_descriptor(ctx, instr, false);
>  		vindex = LLVMBuildExtractElement(ctx->ac.builder, get_src(ctx, instr->src[0]),
>  						 ctx->ac.i32_0, "");
>  
> @@ -2262,20 +2281,7 @@ static void visit_image_store(struct ac_nir_context *ctx,
>  		glc = ctx->ac.i1true;
>  
>  	if (dim == GLSL_SAMPLER_DIM_BUF) {
> -		LLVMValueRef rsrc = get_sampler_desc(ctx, instr->variables[0], AC_DESC_BUFFER, NULL, true, true);
> -
> -		if (ctx->abi->gfx9_stride_size_workaround) {
> -			LLVMValueRef elem_count = LLVMBuildExtractElement(ctx->ac.builder, rsrc, LLVMConstInt(ctx->ac.i32, 2, 0), "");
> -			LLVMValueRef stride = LLVMBuildExtractElement(ctx->ac.builder, rsrc, LLVMConstInt(ctx->ac.i32, 1, 0), "");
> -			stride = LLVMBuildLShr(ctx->ac.builder, stride, LLVMConstInt(ctx->ac.i32, 16, 0), "");
> -
> -			LLVMValueRef new_elem_count = LLVMBuildSelect(ctx->ac.builder,
> -			                                              LLVMBuildICmp(ctx->ac.builder, LLVMIntUGT, elem_count, stride, ""),
> -			                                              elem_count, stride, "");
> -
> -			rsrc = LLVMBuildInsertElement(ctx->ac.builder, rsrc, new_elem_count,
> -			                              LLVMConstInt(ctx->ac.i32, 2, 0), "");
> -		}
> +		LLVMValueRef rsrc = get_image_buffer_descriptor(ctx, instr, true);
>  
>  		params[0] = ac_to_float(&ctx->ac, get_src(ctx, instr->src[2])); /* data */
>  		params[1] = rsrc;
> @@ -2360,8 +2366,7 @@ static LLVMValueRef visit_image_atomic(struct ac_nir_context *ctx,
>  	params[param_count++] = get_src(ctx, instr->src[2]);
>  
>  	if (glsl_get_sampler_dim(type) == GLSL_SAMPLER_DIM_BUF) {
> -		params[param_count++] = get_sampler_desc(ctx, instr->variables[0], AC_DESC_BUFFER,
> -							 NULL, true, true);
> +		params[param_count++] = get_image_buffer_descriptor(ctx, instr, true);
>  		params[param_count++] = LLVMBuildExtractElement(ctx->ac.builder, get_src(ctx, instr->src[0]),
>  								ctx->ac.i32_0, ""); /* vindex */
>  		params[param_count++] = ctx->ac.i32_0; /* voffset */