From bb1546f55be3b243b71d39e5fb7457c5b21e32c9 Mon Sep 17 00:00:00 2001 From: José Fonseca Date: Fri, 2 Jul 2010 16:57:57 +0100 Subject: gallivm: Move gather functions to its own module. They need to grow, and they provide basic functionality which is not specific to sampling. --- src/gallium/auxiliary/gallivm/lp_bld_gather.c | 148 ++++++++++++++++++++++++++ 1 file changed, 148 insertions(+) create mode 100644 src/gallium/auxiliary/gallivm/lp_bld_gather.c (limited to 'src/gallium/auxiliary/gallivm/lp_bld_gather.c') diff --git a/src/gallium/auxiliary/gallivm/lp_bld_gather.c b/src/gallium/auxiliary/gallivm/lp_bld_gather.c new file mode 100644 index 0000000000..d60472e065 --- /dev/null +++ b/src/gallium/auxiliary/gallivm/lp_bld_gather.c @@ -0,0 +1,148 @@ +/************************************************************************** + * + * Copyright 2010 VMware, Inc. + * All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the + * "Software"), to deal in the Software without restriction, including + * without limitation the rights to use, copy, modify, merge, publish, + * distribute, sub license, and/or sell copies of the Software, and to + * permit persons to whom the Software is furnished to do so, subject to + * the following conditions: + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL + * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, + * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR + * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE + * USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * The above copyright notice and this permission notice (including the + * next paragraph) shall be included in all copies or substantial portions + * of the Software. + * + **************************************************************************/ + + +#include "util/u_debug.h" +#include "lp_bld_debug.h" +#include "lp_bld_const.h" +#include "lp_bld_format.h" +#include "lp_bld_gather.h" + + +/** + * Get the pointer to one element from scatter positions in memory. + * + * @sa lp_build_gather() + */ +LLVMValueRef +lp_build_gather_elem_ptr(LLVMBuilderRef builder, + unsigned length, + LLVMValueRef base_ptr, + LLVMValueRef offsets, + unsigned i) +{ + LLVMValueRef offset; + LLVMValueRef ptr; + + assert(LLVMTypeOf(base_ptr) == LLVMPointerType(LLVMInt8Type(), 0)); + + if (length == 1) { + assert(i == 0); + offset = offsets; + } else { + LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0); + offset = LLVMBuildExtractElement(builder, offsets, index, ""); + } + + ptr = LLVMBuildGEP(builder, base_ptr, &offset, 1, ""); + + return ptr; +} + + +/** + * Gather one element from scatter positions in memory. + * + * @sa lp_build_gather() + */ +LLVMValueRef +lp_build_gather_elem(LLVMBuilderRef builder, + unsigned length, + unsigned src_width, + unsigned dst_width, + LLVMValueRef base_ptr, + LLVMValueRef offsets, + unsigned i) +{ + LLVMTypeRef src_type = LLVMIntType(src_width); + LLVMTypeRef src_ptr_type = LLVMPointerType(src_type, 0); + LLVMTypeRef dst_elem_type = LLVMIntType(dst_width); + LLVMValueRef ptr; + LLVMValueRef res; + + assert(LLVMTypeOf(base_ptr) == LLVMPointerType(LLVMInt8Type(), 0)); + + ptr = lp_build_gather_elem_ptr(builder, length, base_ptr, offsets, i); + ptr = LLVMBuildBitCast(builder, ptr, src_ptr_type, ""); + res = LLVMBuildLoad(builder, ptr, ""); + + assert(src_width <= dst_width); + if (src_width > dst_width) + res = LLVMBuildTrunc(builder, res, dst_elem_type, ""); + if (src_width < dst_width) + res = LLVMBuildZExt(builder, res, dst_elem_type, ""); + + return res; +} + + +/** + * Gather elements from scatter positions in memory into a single vector. + * Use for fetching texels from a texture. + * For SSE, typical values are length=4, src_width=32, dst_width=32. + * + * @param length length of the offsets + * @param src_width src element width in bits + * @param dst_width result element width in bits (src will be expanded to fit) + * @param base_ptr base pointer, should be a i8 pointer type. + * @param offsets vector with offsets + */ +LLVMValueRef +lp_build_gather(LLVMBuilderRef builder, + unsigned length, + unsigned src_width, + unsigned dst_width, + LLVMValueRef base_ptr, + LLVMValueRef offsets) +{ + LLVMValueRef res; + + if (length == 1) { + /* Scalar */ + return lp_build_gather_elem(builder, length, + src_width, dst_width, + base_ptr, offsets, 0); + } else { + /* Vector */ + + LLVMTypeRef dst_elem_type = LLVMIntType(dst_width); + LLVMTypeRef dst_vec_type = LLVMVectorType(dst_elem_type, length); + unsigned i; + + res = LLVMGetUndef(dst_vec_type); + for (i = 0; i < length; ++i) { + LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0); + LLVMValueRef elem; + elem = lp_build_gather_elem(builder, length, + src_width, dst_width, + base_ptr, offsets, i); + res = LLVMBuildInsertElement(builder, res, elem, index, ""); + } + } + + return res; +} -- cgit v1.2.3