C++ LLVMBuildGEP函数代码示例

static void
store_cached_block(struct gallivm_state *gallivm,
                   LLVMValueRef *col,
                   LLVMValueRef tag_value,
                   LLVMValueRef hash_index,
                   LLVMValueRef cache)
{
   LLVMBuilderRef builder = gallivm->builder;
   LLVMValueRef ptr, indices[3];
   LLVMTypeRef type_ptr4x32;
   unsigned count;

   type_ptr4x32 = LLVMPointerType(LLVMVectorType(LLVMInt32TypeInContext(gallivm->context), 4), 0);
   indices[0] = lp_build_const_int32(gallivm, 0);
   indices[1] = lp_build_const_int32(gallivm, LP_BUILD_FORMAT_CACHE_MEMBER_TAGS);
   indices[2] = hash_index;
   ptr = LLVMBuildGEP(builder, cache, indices, ARRAY_SIZE(indices), "");
   LLVMBuildStore(builder, tag_value, ptr);

   indices[1] = lp_build_const_int32(gallivm, LP_BUILD_FORMAT_CACHE_MEMBER_DATA);
   hash_index = LLVMBuildMul(builder, hash_index,
                             lp_build_const_int32(gallivm, 16), "");
   for (count = 0; count < 4; count++) {
      indices[2] = hash_index;
      ptr = LLVMBuildGEP(builder, cache, indices, ARRAY_SIZE(indices), "");
      ptr = LLVMBuildBitCast(builder, ptr, type_ptr4x32, "");
      LLVMBuildStore(builder, col[count], ptr);
      hash_index = LLVMBuildAdd(builder, hash_index,
                                lp_build_const_int32(gallivm, 4), "");
   }
}

/**
 * Generate color blending and color output.
 * \param rt  the render target index (to index blend, colormask state)
 * \param type  the pixel color type
 * \param context_ptr  pointer to the runtime JIT context
 * \param mask  execution mask (active fragment/pixel mask)
 * \param src  colors from the fragment shader
 * \param dst_ptr  the destination color buffer pointer
 */
static void
generate_blend(const struct pipe_blend_state *blend,
               unsigned rt,
               LLVMBuilderRef builder,
               struct lp_type type,
               LLVMValueRef context_ptr,
               LLVMValueRef mask,
               LLVMValueRef *src,
               LLVMValueRef dst_ptr)
{
   struct lp_build_context bld;
   struct lp_build_flow_context *flow;
   struct lp_build_mask_context mask_ctx;
   LLVMTypeRef vec_type;
   LLVMValueRef const_ptr;
   LLVMValueRef con[4];
   LLVMValueRef dst[4];
   LLVMValueRef res[4];
   unsigned chan;

   lp_build_context_init(&bld, builder, type);

   flow = lp_build_flow_create(builder);

   /* we'll use this mask context to skip blending if all pixels are dead */
   lp_build_mask_begin(&mask_ctx, flow, type, mask);

   vec_type = lp_build_vec_type(type);

   const_ptr = lp_jit_context_blend_color(builder, context_ptr);
   const_ptr = LLVMBuildBitCast(builder, const_ptr,
                                LLVMPointerType(vec_type, 0), "");

   /* load constant blend color and colors from the dest color buffer */
   for(chan = 0; chan < 4; ++chan) {
      LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
      con[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, const_ptr, &index, 1, ""), "");

      dst[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dst_ptr, &index, 1, ""), "");

      lp_build_name(con[chan], "con.%c", "rgba"[chan]);
      lp_build_name(dst[chan], "dst.%c", "rgba"[chan]);
   }

   /* do blend */
   lp_build_blend_soa(builder, blend, type, rt, src, dst, con, res);

   /* store results to color buffer */
   for(chan = 0; chan < 4; ++chan) {
      if(blend->rt[rt].colormask & (1 << chan)) {
         LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
         lp_build_name(res[chan], "res.%c", "rgba"[chan]);
         res[chan] = lp_build_select(&bld, mask, res[chan], dst[chan]);
         LLVMBuildStore(builder, res[chan], LLVMBuildGEP(builder, dst_ptr, &index, 1, ""));
      }
   }

   lp_build_mask_end(&mask_ctx);
   lp_build_flow_destroy(flow);
}

/**
 * Generate color blending and color output.
 */
static void
generate_blend(const struct pipe_blend_state *blend,
               LLVMBuilderRef builder,
               struct lp_type type,
               LLVMValueRef context_ptr,
               LLVMValueRef mask,
               LLVMValueRef *src,
               LLVMValueRef dst_ptr)
{
   struct lp_build_context bld;
   struct lp_build_flow_context *flow;
   struct lp_build_mask_context mask_ctx;
   LLVMTypeRef vec_type;
   LLVMTypeRef int_vec_type;
   LLVMValueRef const_ptr;
   LLVMValueRef con[4];
   LLVMValueRef dst[4];
   LLVMValueRef res[4];
   unsigned chan;

   lp_build_context_init(&bld, builder, type);

   flow = lp_build_flow_create(builder);
   lp_build_mask_begin(&mask_ctx, flow, type, mask);

   vec_type = lp_build_vec_type(type);
   int_vec_type = lp_build_int_vec_type(type);

   const_ptr = lp_jit_context_blend_color(builder, context_ptr);
   const_ptr = LLVMBuildBitCast(builder, const_ptr,
                                LLVMPointerType(vec_type, 0), "");

   for(chan = 0; chan < 4; ++chan) {
      LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
      con[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, const_ptr, &index, 1, ""), "");

      dst[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dst_ptr, &index, 1, ""), "");

      lp_build_name(con[chan], "con.%c", "rgba"[chan]);
      lp_build_name(dst[chan], "dst.%c", "rgba"[chan]);
   }

   lp_build_blend_soa(builder, blend, type, src, dst, con, res);

   for(chan = 0; chan < 4; ++chan) {
      if(blend->colormask & (1 << chan)) {
         LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
         lp_build_name(res[chan], "res.%c", "rgba"[chan]);
         res[chan] = lp_build_select(&bld, mask, res[chan], dst[chan]);
         LLVMBuildStore(builder, res[chan], LLVMBuildGEP(builder, dst_ptr, &index, 1, ""));
      }
   }

   lp_build_mask_end(&mask_ctx);
   lp_build_flow_destroy(flow);
}

static LLVMValueRef
add_conv_test(struct gallivm_state *gallivm,
              struct lp_type src_type, unsigned num_srcs,
              struct lp_type dst_type, unsigned num_dsts)
{
   LLVMModuleRef module = gallivm->module;
   LLVMContextRef context = gallivm->context;
   LLVMBuilderRef builder = gallivm->builder;
   LLVMTypeRef args[2];
   LLVMValueRef func;
   LLVMValueRef src_ptr;
   LLVMValueRef dst_ptr;
   LLVMBasicBlockRef block;
   LLVMValueRef src[LP_MAX_VECTOR_LENGTH];
   LLVMValueRef dst[LP_MAX_VECTOR_LENGTH];
   unsigned i;

   args[0] = LLVMPointerType(lp_build_vec_type(gallivm, src_type), 0);
   args[1] = LLVMPointerType(lp_build_vec_type(gallivm, dst_type), 0);

   func = LLVMAddFunction(module, "test",
                          LLVMFunctionType(LLVMVoidTypeInContext(context),
                                           args, 2, 0));
   LLVMSetFunctionCallConv(func, LLVMCCallConv);
   src_ptr = LLVMGetParam(func, 0);
   dst_ptr = LLVMGetParam(func, 1);

   block = LLVMAppendBasicBlockInContext(context, func, "entry");
   LLVMPositionBuilderAtEnd(builder, block);

   for(i = 0; i < num_srcs; ++i) {
      LLVMValueRef index = LLVMConstInt(LLVMInt32TypeInContext(context), i, 0);
      LLVMValueRef ptr = LLVMBuildGEP(builder, src_ptr, &index, 1, "");
      src[i] = LLVMBuildLoad(builder, ptr, "");
   }

   lp_build_conv(gallivm, src_type, dst_type, src, num_srcs, dst, num_dsts);

   for(i = 0; i < num_dsts; ++i) {
      LLVMValueRef index = LLVMConstInt(LLVMInt32TypeInContext(context), i, 0);
      LLVMValueRef ptr = LLVMBuildGEP(builder, dst_ptr, &index, 1, "");
      LLVMBuildStore(builder, dst[i], ptr);
   }

   LLVMBuildRetVoid(builder);;

   gallivm_verify_function(gallivm, func);

   return func;
}

static LLVMValueRef
emit_fetch_temporary(
	struct lp_build_tgsi_context *bld_base,
	const struct tgsi_full_src_register *reg,
	enum tgsi_opcode_type type,
	unsigned swizzle)
{
	struct lp_build_tgsi_soa_context *bld = lp_soa_context(bld_base);
	LLVMBuilderRef builder = bld_base->base.gallivm->builder;
	if (swizzle == ~0) {
		LLVMValueRef values[TGSI_NUM_CHANNELS] = {};
		unsigned chan;
		for (chan = 0; chan < TGSI_NUM_CHANNELS; chan++) {
			values[chan] = emit_fetch_temporary(bld_base, reg, type, chan);
		}
		return lp_build_gather_values(bld_base->base.gallivm, values,
						TGSI_NUM_CHANNELS);
	}

	if (reg->Register.Indirect) {
		LLVMValueRef array_index = emit_array_index(bld, reg, swizzle);
		LLVMValueRef ptr = LLVMBuildGEP(builder, bld->temps_array, &array_index,
						1, "");
		return LLVMBuildLoad(builder, ptr, "");
	} else {
		LLVMValueRef temp_ptr;
		temp_ptr = lp_get_temp_ptr_soa(bld, reg->Register.Index, swizzle);
		return bitcast(bld_base,type,LLVMBuildLoad(builder, temp_ptr, ""));
	}
}

LLVMValueRef build_utcb_load(
	struct llvm_ctx *ctx,
	LLVMValueRef ix,
	const char *name)
{
	return LLVMBuildLoad(ctx->builder,
		LLVMBuildGEP(ctx->builder, ctx->utcb, &ix, 1, "utcb.addr.in"),
		name);
}

void
lp_build_pointer_set(LLVMBuilderRef builder,
                     LLVMValueRef ptr,
                     LLVMValueRef index,
                     LLVMValueRef value)
{
   LLVMValueRef element_ptr;
   element_ptr = LLVMBuildGEP(builder, ptr, &index, 1, "");
   LLVMBuildStore(builder, value, element_ptr);
}

/**
 * @brief lp_build_fetch_rgba_aos_array
 *
 * \param format_desc   describes format of the image we're fetching from
 * \param dst_type      output type
 * \param base_ptr      address of the pixel block (or the texel if uncompressed)
 * \param offset        ptr offset
 */
LLVMValueRef
lp_build_fetch_rgba_aos_array(struct gallivm_state *gallivm,
                              const struct util_format_description *format_desc,
                              struct lp_type dst_type,
                              LLVMValueRef base_ptr,
                              LLVMValueRef offset)
{
    struct lp_build_context bld;
    LLVMBuilderRef builder = gallivm->builder;
    LLVMTypeRef src_elem_type, src_vec_type;
    LLVMValueRef ptr, res = NULL;
    struct lp_type src_type;

    memset(&src_type, 0, sizeof src_type);
    src_type.floating = format_desc->channel[0].type == UTIL_FORMAT_TYPE_FLOAT;
    src_type.fixed    = format_desc->channel[0].type == UTIL_FORMAT_TYPE_FIXED;
    src_type.sign     = format_desc->channel[0].type != UTIL_FORMAT_TYPE_UNSIGNED;
    src_type.norm     = format_desc->channel[0].normalized;
    src_type.width    = format_desc->channel[0].size;
    src_type.length   = format_desc->nr_channels;

    assert(src_type.length <= dst_type.length);

    src_elem_type = lp_build_elem_type(gallivm, src_type);
    src_vec_type  = lp_build_vec_type(gallivm,  src_type);

    /* Read whole vector from memory, unaligned */
    if (!res) {
        ptr = LLVMBuildGEP(builder, base_ptr, &offset, 1, "");
        ptr = LLVMBuildPointerCast(builder, ptr, LLVMPointerType(src_vec_type, 0), "");
        res = LLVMBuildLoad(builder, ptr, "");
        lp_set_load_alignment(res, src_type.width / 8);
    }

    /* Truncate doubles to float */
    if (src_type.floating && src_type.width == 64) {
        src_type.width = 32;
        src_vec_type  = lp_build_vec_type(gallivm,  src_type);

        res = LLVMBuildFPTrunc(builder, res, src_vec_type, "");
    }

    /* Expand to correct length */
    if (src_type.length < dst_type.length) {
        res = lp_build_pad_vector(gallivm, res, src_type, dst_type.length);
        src_type.length = dst_type.length;
    }

    /* Convert to correct format */
    lp_build_conv(gallivm, src_type, dst_type, &res, 1, &res, 1);

    /* Swizzle it */
    lp_build_context_init(&bld, gallivm, dst_type);
    return lp_build_format_swizzle_aos(format_desc, &bld, res);
}

LLVMValueRef gendesc_fieldinfo(compile_t* c, LLVMValueRef desc, size_t index)
{
  LLVMValueRef fields = desc_field(c, desc, DESC_FIELDS);

  LLVMValueRef gep[2];
  gep[0] = LLVMConstInt(c->i32, 0, false);
  gep[1] = LLVMConstInt(c->i32, index, false);

  LLVMValueRef field_desc = LLVMBuildGEP(c->builder, fields, gep, 2, "");
  return LLVMBuildLoad(c->builder, field_desc, "");
}

LLVMValueRef gendesc_vtable(compile_t* c, LLVMValueRef object, size_t colour)
{
  LLVMValueRef desc = gendesc_fetch(c, object);
  LLVMValueRef vtable = LLVMBuildStructGEP(c->builder, desc, DESC_VTABLE, "");

  LLVMValueRef gep[2];
  gep[0] = LLVMConstInt(c->i32, 0, false);
  gep[1] = LLVMConstInt(c->i32, colour, false);

  LLVMValueRef func_ptr = LLVMBuildGEP(c->builder, vtable, gep, 2, "");
  return LLVMBuildLoad(c->builder, func_ptr, "");
}

LLVMValueRef gendesc_istrait(compile_t* c, LLVMValueRef desc, ast_t* type)
{
  // Get the trait identifier.
  reach_type_t* t = reach_type(c->reach, type);
  assert(t != NULL);
  LLVMValueRef trait_id = LLVMConstInt(c->i32, t->type_id, false);

  // Read the count and the trait list from the descriptor.
  LLVMValueRef count = desc_field(c, desc, DESC_TRAIT_COUNT);
  LLVMValueRef list = desc_field(c, desc, DESC_TRAITS);

  LLVMBasicBlockRef entry_block = LLVMGetInsertBlock(c->builder);
  LLVMBasicBlockRef cond_block = codegen_block(c, "cond");
  LLVMBasicBlockRef body_block = codegen_block(c, "body");
  LLVMBasicBlockRef post_block = codegen_block(c, "post");
  LLVMBuildBr(c->builder, cond_block);

  // While the index is less than the count, check an ID.
  LLVMPositionBuilderAtEnd(c->builder, cond_block);
  LLVMValueRef phi = LLVMBuildPhi(c->builder, c->i32, "");
  LLVMValueRef zero = LLVMConstInt(c->i32, 0, false);
  LLVMAddIncoming(phi, &zero, &entry_block, 1);

  LLVMValueRef test = LLVMBuildICmp(c->builder, LLVMIntULT, phi, count, "");
  LLVMBuildCondBr(c->builder, test, body_block, post_block);

  // The phi node is the index. Get ID and compare it.
  LLVMPositionBuilderAtEnd(c->builder, body_block);

  LLVMValueRef gep[2];
  gep[0] = LLVMConstInt(c->i32, 0, false);
  gep[1] = phi;

  LLVMValueRef id_ptr = LLVMBuildGEP(c->builder, list, gep, 2, "");
  LLVMValueRef id = LLVMBuildLoad(c->builder, id_ptr, "");
  LLVMValueRef test_id = LLVMBuildICmp(c->builder, LLVMIntEQ, id, trait_id,
    "");

  // Add one to the phi node.
  LLVMValueRef one = LLVMConstInt(c->i32, 1, false);
  LLVMValueRef inc = LLVMBuildAdd(c->builder, phi, one, "");
  LLVMAddIncoming(phi, &inc, &body_block, 1);

  // Either to the post block or back to the condition.
  LLVMBuildCondBr(c->builder, test_id, post_block, cond_block);

  LLVMPositionBuilderAtEnd(c->builder, post_block);
  LLVMValueRef result = LLVMBuildPhi(c->builder, c->i1, "");
  LLVMAddIncoming(result, &test, &cond_block, 1);
  LLVMAddIncoming(result, &test_id, &body_block, 1);

  return result;
}

LLVMValueRef
ac_build_gep0(struct ac_llvm_context *ctx,
	      LLVMValueRef base_ptr,
	      LLVMValueRef index)
{
	LLVMValueRef indices[2] = {
		LLVMConstInt(ctx->i32, 0, 0),
		index,
	};
	return LLVMBuildGEP(ctx->builder, base_ptr,
			    indices, 2, "");
}

void
lp_build_pointer_set_unaligned(LLVMBuilderRef builder,
                               LLVMValueRef ptr,
                               LLVMValueRef index,
                               LLVMValueRef value,
                               unsigned alignment)
{
   LLVMValueRef element_ptr;
   LLVMValueRef instr;
   element_ptr = LLVMBuildGEP(builder, ptr, &index, 1, "");
   instr = LLVMBuildStore(builder, value, element_ptr);
   lp_set_store_alignment(instr, alignment);
}

/**
 * Return pointer to a single mipmap level.
 * \param data_array  array of pointers to mipmap levels
 * \param level  integer mipmap level
 */
LLVMValueRef
lp_build_get_mipmap_level(struct lp_build_sample_context *bld,
                          LLVMValueRef level)
{
   LLVMBuilderRef builder = bld->gallivm->builder;
   LLVMValueRef indexes[2], data_ptr;

   indexes[0] = lp_build_const_int32(bld->gallivm, 0);
   indexes[1] = level;
   data_ptr = LLVMBuildGEP(builder, bld->data_array, indexes, 2, "");
   data_ptr = LLVMBuildLoad(builder, data_ptr, "");
   return data_ptr;
}

/**
 * Dereference stride_array[mipmap_level] array to get a stride.
 * Return stride as a vector.
 */
static LLVMValueRef
lp_build_get_level_stride_vec(struct lp_build_sample_context *bld,
                              LLVMValueRef stride_array, LLVMValueRef level)
{
   LLVMBuilderRef builder = bld->gallivm->builder;
   LLVMValueRef indexes[2], stride;
   indexes[0] = lp_build_const_int32(bld->gallivm, 0);
   indexes[1] = level;
   stride = LLVMBuildGEP(builder, stride_array, indexes, 2, "");
   stride = LLVMBuildLoad(builder, stride, "");
   stride = lp_build_broadcast_scalar(&bld->int_coord_bld, stride);
   return stride;
}