- args.coords[0] = coord_x;
- args.coords[1] = coord_y;
- if (coord_z)
- args.coords[2] = coord_z;
-
- args.opcode = ac_image_load;
- args.dim = coord_z ? ac_image_2darray : ac_image_2d;
- args.resource = fmask_desc_ptr;
- args.dmask = 0xf;
- args.attributes = AC_FUNC_ATTR_READNONE;
-
- res = ac_build_image_opcode(ctx, &args);
-
- res = ac_to_integer(ctx, res);
- LLVMValueRef four = LLVMConstInt(ctx->i32, 4, false);
- LLVMValueRef F = LLVMConstInt(ctx->i32, 0xf, false);
-
- LLVMValueRef fmask = LLVMBuildExtractElement(ctx->builder,
- res,
- ctx->i32_0, "");
-
- LLVMValueRef sample_index4 =
- LLVMBuildMul(ctx->builder, sample_index, four, "");
- LLVMValueRef shifted_fmask =
- LLVMBuildLShr(ctx->builder, fmask, sample_index4, "");
- LLVMValueRef final_sample =
- LLVMBuildAnd(ctx->builder, shifted_fmask, F, "");
-
- /* Don't rewrite the sample index if WORD1.DATA_FORMAT of the FMASK
- * resource descriptor is 0 (invalid),
- */
- LLVMValueRef fmask_desc =
- LLVMBuildBitCast(ctx->builder, fmask_desc_ptr,
- ctx->v8i32, "");
-
- LLVMValueRef fmask_word1 =
- LLVMBuildExtractElement(ctx->builder, fmask_desc,
- ctx->i32_1, "");
-
- LLVMValueRef word1_is_nonzero =
- LLVMBuildICmp(ctx->builder, LLVMIntNE,
- fmask_word1, ctx->i32_0, "");
-
- /* Replace the MSAA sample index. */
- sample_index =
- LLVMBuildSelect(ctx->builder, word1_is_nonzero,
- final_sample, sample_index, "");
- return sample_index;