| /************************************************************************** |
| * |
| * Copyright 2009-2010 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 above copyright notice and this permission notice (including the |
| * next paragraph) shall be included in all copies or substantial portions |
| * of the Software. |
| * |
| * 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 VMWARE 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. |
| * |
| **************************************************************************/ |
| |
| |
| /** |
| * @file |
| * Helper |
| * |
| * LLVM IR doesn't support all basic arithmetic operations we care about (most |
| * notably min/max and saturated operations), and it is often necessary to |
| * resort machine-specific intrinsics directly. The functions here hide all |
| * these implementation details from the other modules. |
| * |
| * We also do simple expressions simplification here. Reasons are: |
| * - it is very easy given we have all necessary information readily available |
| * - LLVM optimization passes fail to simplify several vector expressions |
| * - We often know value constraints which the optimization passes have no way |
| * of knowing, such as when source arguments are known to be in [0, 1] range. |
| * |
| * @author Jose Fonseca <jfonseca@vmware.com> |
| */ |
| |
| |
| #include "util/u_memory.h" |
| #include "util/u_debug.h" |
| #include "util/u_math.h" |
| #include "util/u_string.h" |
| #include "util/u_cpu_detect.h" |
| |
| #include "lp_bld_type.h" |
| #include "lp_bld_const.h" |
| #include "lp_bld_init.h" |
| #include "lp_bld_intr.h" |
| #include "lp_bld_logic.h" |
| #include "lp_bld_pack.h" |
| #include "lp_bld_debug.h" |
| #include "lp_bld_arit.h" |
| |
| |
| #define EXP_POLY_DEGREE 5 |
| |
| #define LOG_POLY_DEGREE 4 |
| |
| |
| /** |
| * Generate min(a, b) |
| * No checks for special case values of a or b = 1 or 0 are done. |
| */ |
| static LLVMValueRef |
| lp_build_min_simple(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| const struct lp_type type = bld->type; |
| const char *intrinsic = NULL; |
| unsigned intr_size = 0; |
| LLVMValueRef cond; |
| |
| assert(lp_check_value(type, a)); |
| assert(lp_check_value(type, b)); |
| |
| /* TODO: optimize the constant case */ |
| |
| if (type.floating && util_cpu_caps.has_sse) { |
| if (type.width == 32) { |
| if (type.length == 1) { |
| intrinsic = "llvm.x86.sse.min.ss"; |
| intr_size = 128; |
| } |
| else if (type.length <= 4 || !util_cpu_caps.has_avx) { |
| intrinsic = "llvm.x86.sse.min.ps"; |
| intr_size = 128; |
| } |
| else { |
| intrinsic = "llvm.x86.avx.min.ps.256"; |
| intr_size = 256; |
| } |
| } |
| if (type.width == 64 && util_cpu_caps.has_sse2) { |
| if (type.length == 1) { |
| intrinsic = "llvm.x86.sse2.min.sd"; |
| intr_size = 128; |
| } |
| else if (type.length == 2 || !util_cpu_caps.has_avx) { |
| intrinsic = "llvm.x86.sse2.min.pd"; |
| intr_size = 128; |
| } |
| else { |
| intrinsic = "llvm.x86.avx.min.pd.256"; |
| intr_size = 256; |
| } |
| } |
| } |
| else if (util_cpu_caps.has_sse2 && type.length >= 2) { |
| intr_size = 128; |
| if ((type.width == 8 || type.width == 16) && |
| (type.width * type.length <= 64) && |
| (gallivm_debug & GALLIVM_DEBUG_PERF)) { |
| debug_printf("%s: inefficient code, bogus shuffle due to packing\n", |
| __FUNCTION__); |
| } |
| if (type.width == 8 && !type.sign) { |
| intrinsic = "llvm.x86.sse2.pminu.b"; |
| } |
| else if (type.width == 16 && type.sign) { |
| intrinsic = "llvm.x86.sse2.pmins.w"; |
| } |
| if (util_cpu_caps.has_sse4_1) { |
| if (type.width == 8 && type.sign) { |
| intrinsic = "llvm.x86.sse41.pminsb"; |
| } |
| if (type.width == 16 && !type.sign) { |
| intrinsic = "llvm.x86.sse41.pminuw"; |
| } |
| if (type.width == 32 && !type.sign) { |
| intrinsic = "llvm.x86.sse41.pminud"; |
| } |
| if (type.width == 32 && type.sign) { |
| intrinsic = "llvm.x86.sse41.pminsd"; |
| } |
| } |
| } |
| |
| if(intrinsic) { |
| return lp_build_intrinsic_binary_anylength(bld->gallivm, intrinsic, |
| type, |
| intr_size, a, b); |
| } |
| |
| cond = lp_build_cmp(bld, PIPE_FUNC_LESS, a, b); |
| return lp_build_select(bld, cond, a, b); |
| } |
| |
| |
| /** |
| * Generate max(a, b) |
| * No checks for special case values of a or b = 1 or 0 are done. |
| */ |
| static LLVMValueRef |
| lp_build_max_simple(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| const struct lp_type type = bld->type; |
| const char *intrinsic = NULL; |
| unsigned intr_size = 0; |
| LLVMValueRef cond; |
| |
| assert(lp_check_value(type, a)); |
| assert(lp_check_value(type, b)); |
| |
| /* TODO: optimize the constant case */ |
| |
| if (type.floating && util_cpu_caps.has_sse) { |
| if (type.width == 32) { |
| if (type.length == 1) { |
| intrinsic = "llvm.x86.sse.max.ss"; |
| intr_size = 128; |
| } |
| else if (type.length <= 4 || !util_cpu_caps.has_avx) { |
| intrinsic = "llvm.x86.sse.max.ps"; |
| intr_size = 128; |
| } |
| else { |
| intrinsic = "llvm.x86.avx.max.ps.256"; |
| intr_size = 256; |
| } |
| } |
| if (type.width == 64 && util_cpu_caps.has_sse2) { |
| if (type.length == 1) { |
| intrinsic = "llvm.x86.sse2.max.sd"; |
| intr_size = 128; |
| } |
| else if (type.length == 2 || !util_cpu_caps.has_avx) { |
| intrinsic = "llvm.x86.sse2.max.pd"; |
| intr_size = 128; |
| } |
| else { |
| intrinsic = "llvm.x86.avx.max.pd.256"; |
| intr_size = 256; |
| } |
| } |
| } |
| else if (util_cpu_caps.has_sse2 && type.length >= 2) { |
| intr_size = 128; |
| if ((type.width == 8 || type.width == 16) && |
| (type.width * type.length <= 64) && |
| (gallivm_debug & GALLIVM_DEBUG_PERF)) { |
| debug_printf("%s: inefficient code, bogus shuffle due to packing\n", |
| __FUNCTION__); |
| } |
| if (type.width == 8 && !type.sign) { |
| intrinsic = "llvm.x86.sse2.pmaxu.b"; |
| intr_size = 128; |
| } |
| else if (type.width == 16 && type.sign) { |
| intrinsic = "llvm.x86.sse2.pmaxs.w"; |
| } |
| if (util_cpu_caps.has_sse4_1) { |
| if (type.width == 8 && type.sign) { |
| intrinsic = "llvm.x86.sse41.pmaxsb"; |
| } |
| if (type.width == 16 && !type.sign) { |
| intrinsic = "llvm.x86.sse41.pmaxuw"; |
| } |
| if (type.width == 32 && !type.sign) { |
| intrinsic = "llvm.x86.sse41.pmaxud"; |
| } |
| if (type.width == 32 && type.sign) { |
| intrinsic = "llvm.x86.sse41.pmaxsd"; |
| } |
| } |
| } |
| |
| if(intrinsic) { |
| return lp_build_intrinsic_binary_anylength(bld->gallivm, intrinsic, |
| type, |
| intr_size, a, b); |
| } |
| |
| cond = lp_build_cmp(bld, PIPE_FUNC_GREATER, a, b); |
| return lp_build_select(bld, cond, a, b); |
| } |
| |
| |
| /** |
| * Generate 1 - a, or ~a depending on bld->type. |
| */ |
| LLVMValueRef |
| lp_build_comp(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(lp_check_value(type, a)); |
| |
| if(a == bld->one) |
| return bld->zero; |
| if(a == bld->zero) |
| return bld->one; |
| |
| if(type.norm && !type.floating && !type.fixed && !type.sign) { |
| if(LLVMIsConstant(a)) |
| return LLVMConstNot(a); |
| else |
| return LLVMBuildNot(builder, a, ""); |
| } |
| |
| if(LLVMIsConstant(a)) |
| if (type.floating) |
| return LLVMConstFSub(bld->one, a); |
| else |
| return LLVMConstSub(bld->one, a); |
| else |
| if (type.floating) |
| return LLVMBuildFSub(builder, bld->one, a, ""); |
| else |
| return LLVMBuildSub(builder, bld->one, a, ""); |
| } |
| |
| |
| /** |
| * Generate a + b |
| */ |
| LLVMValueRef |
| lp_build_add(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef res; |
| |
| assert(lp_check_value(type, a)); |
| assert(lp_check_value(type, b)); |
| |
| if(a == bld->zero) |
| return b; |
| if(b == bld->zero) |
| return a; |
| if(a == bld->undef || b == bld->undef) |
| return bld->undef; |
| |
| if(bld->type.norm) { |
| const char *intrinsic = NULL; |
| |
| if(a == bld->one || b == bld->one) |
| return bld->one; |
| |
| if(util_cpu_caps.has_sse2 && |
| type.width * type.length == 128 && |
| !type.floating && !type.fixed) { |
| if(type.width == 8) |
| intrinsic = type.sign ? "llvm.x86.sse2.padds.b" : "llvm.x86.sse2.paddus.b"; |
| if(type.width == 16) |
| intrinsic = type.sign ? "llvm.x86.sse2.padds.w" : "llvm.x86.sse2.paddus.w"; |
| } |
| |
| if(intrinsic) |
| return lp_build_intrinsic_binary(builder, intrinsic, lp_build_vec_type(bld->gallivm, bld->type), a, b); |
| } |
| |
| if(LLVMIsConstant(a) && LLVMIsConstant(b)) |
| if (type.floating) |
| res = LLVMConstFAdd(a, b); |
| else |
| res = LLVMConstAdd(a, b); |
| else |
| if (type.floating) |
| res = LLVMBuildFAdd(builder, a, b, ""); |
| else |
| res = LLVMBuildAdd(builder, a, b, ""); |
| |
| /* clamp to ceiling of 1.0 */ |
| if(bld->type.norm && (bld->type.floating || bld->type.fixed)) |
| res = lp_build_min_simple(bld, res, bld->one); |
| |
| /* XXX clamp to floor of -1 or 0??? */ |
| |
| return res; |
| } |
| |
| |
| /** Return the scalar sum of the elements of a. |
| * Should avoid this operation whenever possible. |
| */ |
| LLVMValueRef |
| lp_build_horizontal_add(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef index, res; |
| unsigned i, length; |
| LLVMValueRef shuffles1[LP_MAX_VECTOR_LENGTH / 2]; |
| LLVMValueRef shuffles2[LP_MAX_VECTOR_LENGTH / 2]; |
| LLVMValueRef vecres, elem2; |
| |
| assert(lp_check_value(type, a)); |
| |
| if (type.length == 1) { |
| return a; |
| } |
| |
| assert(!bld->type.norm); |
| |
| /* |
| * for byte vectors can do much better with psadbw. |
| * Using repeated shuffle/adds here. Note with multiple vectors |
| * this can be done more efficiently as outlined in the intel |
| * optimization manual. |
| * Note: could cause data rearrangement if used with smaller element |
| * sizes. |
| */ |
| |
| vecres = a; |
| length = type.length / 2; |
| while (length > 1) { |
| LLVMValueRef vec1, vec2; |
| for (i = 0; i < length; i++) { |
| shuffles1[i] = lp_build_const_int32(bld->gallivm, i); |
| shuffles2[i] = lp_build_const_int32(bld->gallivm, i + length); |
| } |
| vec1 = LLVMBuildShuffleVector(builder, vecres, vecres, |
| LLVMConstVector(shuffles1, length), ""); |
| vec2 = LLVMBuildShuffleVector(builder, vecres, vecres, |
| LLVMConstVector(shuffles2, length), ""); |
| if (type.floating) { |
| vecres = LLVMBuildFAdd(builder, vec1, vec2, ""); |
| } |
| else { |
| vecres = LLVMBuildAdd(builder, vec1, vec2, ""); |
| } |
| length = length >> 1; |
| } |
| |
| /* always have vector of size 2 here */ |
| assert(length == 1); |
| |
| index = lp_build_const_int32(bld->gallivm, 0); |
| res = LLVMBuildExtractElement(builder, vecres, index, ""); |
| index = lp_build_const_int32(bld->gallivm, 1); |
| elem2 = LLVMBuildExtractElement(builder, vecres, index, ""); |
| |
| if (type.floating) |
| res = LLVMBuildFAdd(builder, res, elem2, ""); |
| else |
| res = LLVMBuildAdd(builder, res, elem2, ""); |
| |
| return res; |
| } |
| |
| /** |
| * Return the horizontal sums of 4 float vectors as a float4 vector. |
| * This uses the technique as outlined in Intel Optimization Manual. |
| */ |
| static LLVMValueRef |
| lp_build_horizontal_add4x4f(struct lp_build_context *bld, |
| LLVMValueRef src[4]) |
| { |
| struct gallivm_state *gallivm = bld->gallivm; |
| LLVMBuilderRef builder = gallivm->builder; |
| LLVMValueRef shuffles[4]; |
| LLVMValueRef tmp[4]; |
| LLVMValueRef sumtmp[2], shuftmp[2]; |
| |
| /* lower half of regs */ |
| shuffles[0] = lp_build_const_int32(gallivm, 0); |
| shuffles[1] = lp_build_const_int32(gallivm, 1); |
| shuffles[2] = lp_build_const_int32(gallivm, 4); |
| shuffles[3] = lp_build_const_int32(gallivm, 5); |
| tmp[0] = LLVMBuildShuffleVector(builder, src[0], src[1], |
| LLVMConstVector(shuffles, 4), ""); |
| tmp[2] = LLVMBuildShuffleVector(builder, src[2], src[3], |
| LLVMConstVector(shuffles, 4), ""); |
| |
| /* upper half of regs */ |
| shuffles[0] = lp_build_const_int32(gallivm, 2); |
| shuffles[1] = lp_build_const_int32(gallivm, 3); |
| shuffles[2] = lp_build_const_int32(gallivm, 6); |
| shuffles[3] = lp_build_const_int32(gallivm, 7); |
| tmp[1] = LLVMBuildShuffleVector(builder, src[0], src[1], |
| LLVMConstVector(shuffles, 4), ""); |
| tmp[3] = LLVMBuildShuffleVector(builder, src[2], src[3], |
| LLVMConstVector(shuffles, 4), ""); |
| |
| sumtmp[0] = LLVMBuildFAdd(builder, tmp[0], tmp[1], ""); |
| sumtmp[1] = LLVMBuildFAdd(builder, tmp[2], tmp[3], ""); |
| |
| shuffles[0] = lp_build_const_int32(gallivm, 0); |
| shuffles[1] = lp_build_const_int32(gallivm, 2); |
| shuffles[2] = lp_build_const_int32(gallivm, 4); |
| shuffles[3] = lp_build_const_int32(gallivm, 6); |
| shuftmp[0] = LLVMBuildShuffleVector(builder, sumtmp[0], sumtmp[1], |
| LLVMConstVector(shuffles, 4), ""); |
| |
| shuffles[0] = lp_build_const_int32(gallivm, 1); |
| shuffles[1] = lp_build_const_int32(gallivm, 3); |
| shuffles[2] = lp_build_const_int32(gallivm, 5); |
| shuffles[3] = lp_build_const_int32(gallivm, 7); |
| shuftmp[1] = LLVMBuildShuffleVector(builder, sumtmp[0], sumtmp[1], |
| LLVMConstVector(shuffles, 4), ""); |
| |
| return LLVMBuildFAdd(builder, shuftmp[0], shuftmp[1], ""); |
| } |
| |
| |
| /* |
| * partially horizontally add 2-4 float vectors with length nx4, |
| * i.e. only four adjacent values in each vector will be added, |
| * assuming values are really grouped in 4 which also determines |
| * output order. |
| * |
| * Return a vector of the same length as the initial vectors, |
| * with the excess elements (if any) being undefined. |
| * The element order is independent of number of input vectors. |
| * For 3 vectors x0x1x2x3x4x5x6x7, y0y1y2y3y4y5y6y7, z0z1z2z3z4z5z6z7 |
| * the output order thus will be |
| * sumx0-x3,sumy0-y3,sumz0-z3,undef,sumx4-x7,sumy4-y7,sumz4z7,undef |
| */ |
| LLVMValueRef |
| lp_build_hadd_partial4(struct lp_build_context *bld, |
| LLVMValueRef vectors[], |
| unsigned num_vecs) |
| { |
| struct gallivm_state *gallivm = bld->gallivm; |
| LLVMBuilderRef builder = gallivm->builder; |
| LLVMValueRef ret_vec; |
| LLVMValueRef tmp[4]; |
| const char *intrinsic = NULL; |
| |
| assert(num_vecs >= 2 && num_vecs <= 4); |
| assert(bld->type.floating); |
| |
| /* only use this with at least 2 vectors, as it is sort of expensive |
| * (depending on cpu) and we always need two horizontal adds anyway, |
| * so a shuffle/add approach might be better. |
| */ |
| |
| tmp[0] = vectors[0]; |
| tmp[1] = vectors[1]; |
| |
| tmp[2] = num_vecs > 2 ? vectors[2] : vectors[0]; |
| tmp[3] = num_vecs > 3 ? vectors[3] : vectors[0]; |
| |
| if (util_cpu_caps.has_sse3 && bld->type.width == 32 && |
| bld->type.length == 4) { |
| intrinsic = "llvm.x86.sse3.hadd.ps"; |
| } |
| else if (util_cpu_caps.has_avx && bld->type.width == 32 && |
| bld->type.length == 8) { |
| intrinsic = "llvm.x86.avx.hadd.ps.256"; |
| } |
| if (intrinsic) { |
| tmp[0] = lp_build_intrinsic_binary(builder, intrinsic, |
| lp_build_vec_type(gallivm, bld->type), |
| tmp[0], tmp[1]); |
| if (num_vecs > 2) { |
| tmp[1] = lp_build_intrinsic_binary(builder, intrinsic, |
| lp_build_vec_type(gallivm, bld->type), |
| tmp[2], tmp[3]); |
| } |
| else { |
| tmp[1] = tmp[0]; |
| } |
| return lp_build_intrinsic_binary(builder, intrinsic, |
| lp_build_vec_type(gallivm, bld->type), |
| tmp[0], tmp[1]); |
| } |
| |
| if (bld->type.length == 4) { |
| ret_vec = lp_build_horizontal_add4x4f(bld, tmp); |
| } |
| else { |
| LLVMValueRef partres[LP_MAX_VECTOR_LENGTH/4]; |
| unsigned j; |
| unsigned num_iter = bld->type.length / 4; |
| struct lp_type parttype = bld->type; |
| parttype.length = 4; |
| for (j = 0; j < num_iter; j++) { |
| LLVMValueRef partsrc[4]; |
| unsigned i; |
| for (i = 0; i < 4; i++) { |
| partsrc[i] = lp_build_extract_range(gallivm, tmp[i], j*4, 4); |
| } |
| partres[j] = lp_build_horizontal_add4x4f(bld, partsrc); |
| } |
| ret_vec = lp_build_concat(gallivm, partres, parttype, num_iter); |
| } |
| return ret_vec; |
| } |
| |
| /** |
| * Generate a - b |
| */ |
| LLVMValueRef |
| lp_build_sub(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef res; |
| |
| assert(lp_check_value(type, a)); |
| assert(lp_check_value(type, b)); |
| |
| if(b == bld->zero) |
| return a; |
| if(a == bld->undef || b == bld->undef) |
| return bld->undef; |
| if(a == b) |
| return bld->zero; |
| |
| if(bld->type.norm) { |
| const char *intrinsic = NULL; |
| |
| if(b == bld->one) |
| return bld->zero; |
| |
| if(util_cpu_caps.has_sse2 && |
| type.width * type.length == 128 && |
| !type.floating && !type.fixed) { |
| if(type.width == 8) |
| intrinsic = type.sign ? "llvm.x86.sse2.psubs.b" : "llvm.x86.sse2.psubus.b"; |
| if(type.width == 16) |
| intrinsic = type.sign ? "llvm.x86.sse2.psubs.w" : "llvm.x86.sse2.psubus.w"; |
| } |
| |
| if(intrinsic) |
| return lp_build_intrinsic_binary(builder, intrinsic, lp_build_vec_type(bld->gallivm, bld->type), a, b); |
| } |
| |
| if(LLVMIsConstant(a) && LLVMIsConstant(b)) |
| if (type.floating) |
| res = LLVMConstFSub(a, b); |
| else |
| res = LLVMConstSub(a, b); |
| else |
| if (type.floating) |
| res = LLVMBuildFSub(builder, a, b, ""); |
| else |
| res = LLVMBuildSub(builder, a, b, ""); |
| |
| if(bld->type.norm && (bld->type.floating || bld->type.fixed)) |
| res = lp_build_max_simple(bld, res, bld->zero); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Normalized 8bit multiplication. |
| * |
| * - alpha plus one |
| * |
| * makes the following approximation to the division (Sree) |
| * |
| * a*b/255 ~= (a*(b + 1)) >> 256 |
| * |
| * which is the fastest method that satisfies the following OpenGL criteria |
| * |
| * 0*0 = 0 and 255*255 = 255 |
| * |
| * - geometric series |
| * |
| * takes the geometric series approximation to the division |
| * |
| * t/255 = (t >> 8) + (t >> 16) + (t >> 24) .. |
| * |
| * in this case just the first two terms to fit in 16bit arithmetic |
| * |
| * t/255 ~= (t + (t >> 8)) >> 8 |
| * |
| * note that just by itself it doesn't satisfies the OpenGL criteria, as |
| * 255*255 = 254, so the special case b = 255 must be accounted or roundoff |
| * must be used |
| * |
| * - geometric series plus rounding |
| * |
| * when using a geometric series division instead of truncating the result |
| * use roundoff in the approximation (Jim Blinn) |
| * |
| * t/255 ~= (t + (t >> 8) + 0x80) >> 8 |
| * |
| * achieving the exact results |
| * |
| * @sa Alvy Ray Smith, Image Compositing Fundamentals, Tech Memo 4, Aug 15, 1995, |
| * ftp://ftp.alvyray.com/Acrobat/4_Comp.pdf |
| * @sa Michael Herf, The "double blend trick", May 2000, |
| * http://www.stereopsis.com/doubleblend.html |
| */ |
| static LLVMValueRef |
| lp_build_mul_u8n(struct gallivm_state *gallivm, |
| struct lp_type i16_type, |
| LLVMValueRef a, LLVMValueRef b) |
| { |
| LLVMBuilderRef builder = gallivm->builder; |
| LLVMValueRef c8; |
| LLVMValueRef ab; |
| |
| assert(!i16_type.floating); |
| assert(lp_check_value(i16_type, a)); |
| assert(lp_check_value(i16_type, b)); |
| |
| c8 = lp_build_const_int_vec(gallivm, i16_type, 8); |
| |
| #if 0 |
| |
| /* a*b/255 ~= (a*(b + 1)) >> 256 */ |
| b = LLVMBuildAdd(builder, b, lp_build_const_int_vec(gallium, i16_type, 1), ""); |
| ab = LLVMBuildMul(builder, a, b, ""); |
| |
| #else |
| |
| /* ab/255 ~= (ab + (ab >> 8) + 0x80) >> 8 */ |
| ab = LLVMBuildMul(builder, a, b, ""); |
| ab = LLVMBuildAdd(builder, ab, LLVMBuildLShr(builder, ab, c8, ""), ""); |
| ab = LLVMBuildAdd(builder, ab, lp_build_const_int_vec(gallivm, i16_type, 0x80), ""); |
| |
| #endif |
| |
| ab = LLVMBuildLShr(builder, ab, c8, ""); |
| |
| return ab; |
| } |
| |
| |
| /** |
| * Generate a * b |
| */ |
| LLVMValueRef |
| lp_build_mul(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef shift; |
| LLVMValueRef res; |
| |
| assert(lp_check_value(type, a)); |
| assert(lp_check_value(type, b)); |
| |
| if(a == bld->zero) |
| return bld->zero; |
| if(a == bld->one) |
| return b; |
| if(b == bld->zero) |
| return bld->zero; |
| if(b == bld->one) |
| return a; |
| if(a == bld->undef || b == bld->undef) |
| return bld->undef; |
| |
| if(!type.floating && !type.fixed && type.norm) { |
| if(type.width == 8) { |
| struct lp_type i16_type = lp_wider_type(type); |
| LLVMValueRef al, ah, bl, bh, abl, abh, ab; |
| |
| lp_build_unpack2(bld->gallivm, type, i16_type, a, &al, &ah); |
| lp_build_unpack2(bld->gallivm, type, i16_type, b, &bl, &bh); |
| |
| /* PMULLW, PSRLW, PADDW */ |
| abl = lp_build_mul_u8n(bld->gallivm, i16_type, al, bl); |
| abh = lp_build_mul_u8n(bld->gallivm, i16_type, ah, bh); |
| |
| ab = lp_build_pack2(bld->gallivm, i16_type, type, abl, abh); |
| |
| return ab; |
| } |
| |
| /* FIXME */ |
| assert(0); |
| } |
| |
| if(type.fixed) |
| shift = lp_build_const_int_vec(bld->gallivm, type, type.width/2); |
| else |
| shift = NULL; |
| |
| if(LLVMIsConstant(a) && LLVMIsConstant(b)) { |
| if (type.floating) |
| res = LLVMConstFMul(a, b); |
| else |
| res = LLVMConstMul(a, b); |
| if(shift) { |
| if(type.sign) |
| res = LLVMConstAShr(res, shift); |
| else |
| res = LLVMConstLShr(res, shift); |
| } |
| } |
| else { |
| if (type.floating) |
| res = LLVMBuildFMul(builder, a, b, ""); |
| else |
| res = LLVMBuildMul(builder, a, b, ""); |
| if(shift) { |
| if(type.sign) |
| res = LLVMBuildAShr(builder, res, shift, ""); |
| else |
| res = LLVMBuildLShr(builder, res, shift, ""); |
| } |
| } |
| |
| return res; |
| } |
| |
| |
| /** |
| * Small vector x scale multiplication optimization. |
| */ |
| LLVMValueRef |
| lp_build_mul_imm(struct lp_build_context *bld, |
| LLVMValueRef a, |
| int b) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef factor; |
| |
| assert(lp_check_value(bld->type, a)); |
| |
| if(b == 0) |
| return bld->zero; |
| |
| if(b == 1) |
| return a; |
| |
| if(b == -1) |
| return lp_build_negate(bld, a); |
| |
| if(b == 2 && bld->type.floating) |
| return lp_build_add(bld, a, a); |
| |
| if(util_is_power_of_two(b)) { |
| unsigned shift = ffs(b) - 1; |
| |
| if(bld->type.floating) { |
| #if 0 |
| /* |
| * Power of two multiplication by directly manipulating the exponent. |
| * |
| * XXX: This might not be always faster, it will introduce a small error |
| * for multiplication by zero, and it will produce wrong results |
| * for Inf and NaN. |
| */ |
| unsigned mantissa = lp_mantissa(bld->type); |
| factor = lp_build_const_int_vec(bld->gallivm, bld->type, (unsigned long long)shift << mantissa); |
| a = LLVMBuildBitCast(builder, a, lp_build_int_vec_type(bld->type), ""); |
| a = LLVMBuildAdd(builder, a, factor, ""); |
| a = LLVMBuildBitCast(builder, a, lp_build_vec_type(bld->gallivm, bld->type), ""); |
| return a; |
| #endif |
| } |
| else { |
| factor = lp_build_const_vec(bld->gallivm, bld->type, shift); |
| return LLVMBuildShl(builder, a, factor, ""); |
| } |
| } |
| |
| factor = lp_build_const_vec(bld->gallivm, bld->type, (double)b); |
| return lp_build_mul(bld, a, factor); |
| } |
| |
| |
| /** |
| * Generate a / b |
| */ |
| LLVMValueRef |
| lp_build_div(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(lp_check_value(type, a)); |
| assert(lp_check_value(type, b)); |
| |
| if(a == bld->zero) |
| return bld->zero; |
| if(a == bld->one) |
| return lp_build_rcp(bld, b); |
| if(b == bld->zero) |
| return bld->undef; |
| if(b == bld->one) |
| return a; |
| if(a == bld->undef || b == bld->undef) |
| return bld->undef; |
| |
| if(LLVMIsConstant(a) && LLVMIsConstant(b)) { |
| if (type.floating) |
| return LLVMConstFDiv(a, b); |
| else if (type.sign) |
| return LLVMConstSDiv(a, b); |
| else |
| return LLVMConstUDiv(a, b); |
| } |
| |
| if(((util_cpu_caps.has_sse && type.width == 32 && type.length == 4) || |
| (util_cpu_caps.has_avx && type.width == 32 && type.length == 8)) && |
| type.floating) |
| return lp_build_mul(bld, a, lp_build_rcp(bld, b)); |
| |
| if (type.floating) |
| return LLVMBuildFDiv(builder, a, b, ""); |
| else if (type.sign) |
| return LLVMBuildSDiv(builder, a, b, ""); |
| else |
| return LLVMBuildUDiv(builder, a, b, ""); |
| } |
| |
| |
| /** |
| * Linear interpolation -- without any checks. |
| * |
| * @sa http://www.stereopsis.com/doubleblend.html |
| */ |
| static INLINE LLVMValueRef |
| lp_build_lerp_simple(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef v0, |
| LLVMValueRef v1) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef delta; |
| LLVMValueRef res; |
| |
| assert(lp_check_value(bld->type, x)); |
| assert(lp_check_value(bld->type, v0)); |
| assert(lp_check_value(bld->type, v1)); |
| |
| delta = lp_build_sub(bld, v1, v0); |
| |
| res = lp_build_mul(bld, x, delta); |
| |
| res = lp_build_add(bld, v0, res); |
| |
| if (bld->type.fixed) { |
| /* XXX: This step is necessary for lerping 8bit colors stored on 16bits, |
| * but it will be wrong for other uses. Basically we need a more |
| * powerful lp_type, capable of further distinguishing the values |
| * interpretation from the value storage. */ |
| res = LLVMBuildAnd(builder, res, lp_build_const_int_vec(bld->gallivm, bld->type, (1 << bld->type.width/2) - 1), ""); |
| } |
| |
| return res; |
| } |
| |
| |
| /** |
| * Linear interpolation. |
| */ |
| LLVMValueRef |
| lp_build_lerp(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef v0, |
| LLVMValueRef v1) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef res; |
| |
| assert(lp_check_value(type, x)); |
| assert(lp_check_value(type, v0)); |
| assert(lp_check_value(type, v1)); |
| |
| if (type.norm) { |
| struct lp_type wide_type; |
| struct lp_build_context wide_bld; |
| LLVMValueRef xl, xh, v0l, v0h, v1l, v1h, resl, resh; |
| LLVMValueRef shift; |
| |
| assert(type.length >= 2); |
| assert(!type.sign); |
| |
| /* |
| * Create a wider type, enough to hold the intermediate result of the |
| * multiplication. |
| */ |
| memset(&wide_type, 0, sizeof wide_type); |
| wide_type.fixed = TRUE; |
| wide_type.width = type.width*2; |
| wide_type.length = type.length/2; |
| |
| lp_build_context_init(&wide_bld, bld->gallivm, wide_type); |
| |
| lp_build_unpack2(bld->gallivm, type, wide_type, x, &xl, &xh); |
| lp_build_unpack2(bld->gallivm, type, wide_type, v0, &v0l, &v0h); |
| lp_build_unpack2(bld->gallivm, type, wide_type, v1, &v1l, &v1h); |
| |
| /* |
| * Scale x from [0, 255] to [0, 256] |
| */ |
| |
| shift = lp_build_const_int_vec(bld->gallivm, wide_type, type.width - 1); |
| |
| xl = lp_build_add(&wide_bld, xl, |
| LLVMBuildAShr(builder, xl, shift, "")); |
| xh = lp_build_add(&wide_bld, xh, |
| LLVMBuildAShr(builder, xh, shift, "")); |
| |
| /* |
| * Lerp both halves. |
| */ |
| |
| resl = lp_build_lerp_simple(&wide_bld, xl, v0l, v1l); |
| resh = lp_build_lerp_simple(&wide_bld, xh, v0h, v1h); |
| |
| res = lp_build_pack2(bld->gallivm, wide_type, type, resl, resh); |
| } else { |
| res = lp_build_lerp_simple(bld, x, v0, v1); |
| } |
| |
| return res; |
| } |
| |
| |
| LLVMValueRef |
| lp_build_lerp_2d(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef y, |
| LLVMValueRef v00, |
| LLVMValueRef v01, |
| LLVMValueRef v10, |
| LLVMValueRef v11) |
| { |
| LLVMValueRef v0 = lp_build_lerp(bld, x, v00, v01); |
| LLVMValueRef v1 = lp_build_lerp(bld, x, v10, v11); |
| return lp_build_lerp(bld, y, v0, v1); |
| } |
| |
| |
| /** |
| * Generate min(a, b) |
| * Do checks for special cases. |
| */ |
| LLVMValueRef |
| lp_build_min(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| assert(lp_check_value(bld->type, a)); |
| assert(lp_check_value(bld->type, b)); |
| |
| if(a == bld->undef || b == bld->undef) |
| return bld->undef; |
| |
| if(a == b) |
| return a; |
| |
| if (bld->type.norm) { |
| if (!bld->type.sign) { |
| if (a == bld->zero || b == bld->zero) { |
| return bld->zero; |
| } |
| } |
| if(a == bld->one) |
| return b; |
| if(b == bld->one) |
| return a; |
| } |
| |
| return lp_build_min_simple(bld, a, b); |
| } |
| |
| |
| /** |
| * Generate max(a, b) |
| * Do checks for special cases. |
| */ |
| LLVMValueRef |
| lp_build_max(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef b) |
| { |
| assert(lp_check_value(bld->type, a)); |
| assert(lp_check_value(bld->type, b)); |
| |
| if(a == bld->undef || b == bld->undef) |
| return bld->undef; |
| |
| if(a == b) |
| return a; |
| |
| if(bld->type.norm) { |
| if(a == bld->one || b == bld->one) |
| return bld->one; |
| if (!bld->type.sign) { |
| if (a == bld->zero) { |
| return b; |
| } |
| if (b == bld->zero) { |
| return a; |
| } |
| } |
| } |
| |
| return lp_build_max_simple(bld, a, b); |
| } |
| |
| |
| /** |
| * Generate clamp(a, min, max) |
| * Do checks for special cases. |
| */ |
| LLVMValueRef |
| lp_build_clamp(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef min, |
| LLVMValueRef max) |
| { |
| assert(lp_check_value(bld->type, a)); |
| assert(lp_check_value(bld->type, min)); |
| assert(lp_check_value(bld->type, max)); |
| |
| a = lp_build_min(bld, a, max); |
| a = lp_build_max(bld, a, min); |
| return a; |
| } |
| |
| |
| /** |
| * Generate abs(a) |
| */ |
| LLVMValueRef |
| lp_build_abs(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| |
| assert(lp_check_value(type, a)); |
| |
| if(!type.sign) |
| return a; |
| |
| if(type.floating) { |
| /* Mask out the sign bit */ |
| LLVMTypeRef int_vec_type = lp_build_int_vec_type(bld->gallivm, type); |
| unsigned long long absMask = ~(1ULL << (type.width - 1)); |
| LLVMValueRef mask = lp_build_const_int_vec(bld->gallivm, type, ((unsigned long long) absMask)); |
| a = LLVMBuildBitCast(builder, a, int_vec_type, ""); |
| a = LLVMBuildAnd(builder, a, mask, ""); |
| a = LLVMBuildBitCast(builder, a, vec_type, ""); |
| return a; |
| } |
| |
| if(type.width*type.length == 128 && util_cpu_caps.has_ssse3) { |
| switch(type.width) { |
| case 8: |
| return lp_build_intrinsic_unary(builder, "llvm.x86.ssse3.pabs.b.128", vec_type, a); |
| case 16: |
| return lp_build_intrinsic_unary(builder, "llvm.x86.ssse3.pabs.w.128", vec_type, a); |
| case 32: |
| return lp_build_intrinsic_unary(builder, "llvm.x86.ssse3.pabs.d.128", vec_type, a); |
| } |
| } |
| else if (type.width*type.length == 256 && util_cpu_caps.has_ssse3 && |
| (gallivm_debug & GALLIVM_DEBUG_PERF) && |
| (type.width == 8 || type.width == 16 || type.width == 32)) { |
| debug_printf("%s: inefficient code, should split vectors manually\n", |
| __FUNCTION__); |
| } |
| |
| return lp_build_max(bld, a, LLVMBuildNeg(builder, a, "")); |
| } |
| |
| |
| LLVMValueRef |
| lp_build_negate(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| |
| assert(lp_check_value(bld->type, a)); |
| |
| #if HAVE_LLVM >= 0x0207 |
| if (bld->type.floating) |
| a = LLVMBuildFNeg(builder, a, ""); |
| else |
| #endif |
| a = LLVMBuildNeg(builder, a, ""); |
| |
| return a; |
| } |
| |
| |
| /** Return -1, 0 or +1 depending on the sign of a */ |
| LLVMValueRef |
| lp_build_sgn(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef cond; |
| LLVMValueRef res; |
| |
| assert(lp_check_value(type, a)); |
| |
| /* Handle non-zero case */ |
| if(!type.sign) { |
| /* if not zero then sign must be positive */ |
| res = bld->one; |
| } |
| else if(type.floating) { |
| LLVMTypeRef vec_type; |
| LLVMTypeRef int_type; |
| LLVMValueRef mask; |
| LLVMValueRef sign; |
| LLVMValueRef one; |
| unsigned long long maskBit = (unsigned long long)1 << (type.width - 1); |
| |
| int_type = lp_build_int_vec_type(bld->gallivm, type); |
| vec_type = lp_build_vec_type(bld->gallivm, type); |
| mask = lp_build_const_int_vec(bld->gallivm, type, maskBit); |
| |
| /* Take the sign bit and add it to 1 constant */ |
| sign = LLVMBuildBitCast(builder, a, int_type, ""); |
| sign = LLVMBuildAnd(builder, sign, mask, ""); |
| one = LLVMConstBitCast(bld->one, int_type); |
| res = LLVMBuildOr(builder, sign, one, ""); |
| res = LLVMBuildBitCast(builder, res, vec_type, ""); |
| } |
| else |
| { |
| /* signed int/norm/fixed point */ |
| /* could use psign with sse3 and appropriate vectors here */ |
| LLVMValueRef minus_one = lp_build_const_vec(bld->gallivm, type, -1.0); |
| cond = lp_build_cmp(bld, PIPE_FUNC_GREATER, a, bld->zero); |
| res = lp_build_select(bld, cond, bld->one, minus_one); |
| } |
| |
| /* Handle zero */ |
| cond = lp_build_cmp(bld, PIPE_FUNC_EQUAL, a, bld->zero); |
| res = lp_build_select(bld, cond, bld->zero, res); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Set the sign of float vector 'a' according to 'sign'. |
| * If sign==0, return abs(a). |
| * If sign==1, return -abs(a); |
| * Other values for sign produce undefined results. |
| */ |
| LLVMValueRef |
| lp_build_set_sign(struct lp_build_context *bld, |
| LLVMValueRef a, LLVMValueRef sign) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef int_vec_type = lp_build_int_vec_type(bld->gallivm, type); |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMValueRef shift = lp_build_const_int_vec(bld->gallivm, type, type.width - 1); |
| LLVMValueRef mask = lp_build_const_int_vec(bld->gallivm, type, |
| ~((unsigned long long) 1 << (type.width - 1))); |
| LLVMValueRef val, res; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| /* val = reinterpret_cast<int>(a) */ |
| val = LLVMBuildBitCast(builder, a, int_vec_type, ""); |
| /* val = val & mask */ |
| val = LLVMBuildAnd(builder, val, mask, ""); |
| /* sign = sign << shift */ |
| sign = LLVMBuildShl(builder, sign, shift, ""); |
| /* res = val | sign */ |
| res = LLVMBuildOr(builder, val, sign, ""); |
| /* res = reinterpret_cast<float>(res) */ |
| res = LLVMBuildBitCast(builder, res, vec_type, ""); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Convert vector of (or scalar) int to vector of (or scalar) float. |
| */ |
| LLVMValueRef |
| lp_build_int_to_float(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| |
| assert(type.floating); |
| |
| return LLVMBuildSIToFP(builder, a, vec_type, ""); |
| } |
| |
| static boolean |
| sse41_rounding_available(const struct lp_type type) |
| { |
| if ((util_cpu_caps.has_sse4_1 && |
| (type.length == 1 || type.width*type.length == 128)) || |
| (util_cpu_caps.has_avx && type.width*type.length == 256)) |
| return TRUE; |
| |
| return FALSE; |
| } |
| |
| enum lp_build_round_sse41_mode |
| { |
| LP_BUILD_ROUND_SSE41_NEAREST = 0, |
| LP_BUILD_ROUND_SSE41_FLOOR = 1, |
| LP_BUILD_ROUND_SSE41_CEIL = 2, |
| LP_BUILD_ROUND_SSE41_TRUNCATE = 3 |
| }; |
| |
| |
| /** |
| * Helper for SSE4.1's ROUNDxx instructions. |
| * |
| * NOTE: In the SSE4.1's nearest mode, if two values are equally close, the |
| * result is the even value. That is, rounding 2.5 will be 2.0, and not 3.0. |
| */ |
| static INLINE LLVMValueRef |
| lp_build_round_sse41(struct lp_build_context *bld, |
| LLVMValueRef a, |
| enum lp_build_round_sse41_mode mode) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef i32t = LLVMInt32TypeInContext(bld->gallivm->context); |
| const char *intrinsic; |
| LLVMValueRef res; |
| |
| assert(type.floating); |
| |
| assert(lp_check_value(type, a)); |
| assert(util_cpu_caps.has_sse4_1); |
| |
| if (type.length == 1) { |
| LLVMTypeRef vec_type; |
| LLVMValueRef undef; |
| LLVMValueRef args[3]; |
| LLVMValueRef index0 = LLVMConstInt(i32t, 0, 0); |
| |
| switch(type.width) { |
| case 32: |
| intrinsic = "llvm.x86.sse41.round.ss"; |
| break; |
| case 64: |
| intrinsic = "llvm.x86.sse41.round.sd"; |
| break; |
| default: |
| assert(0); |
| return bld->undef; |
| } |
| |
| vec_type = LLVMVectorType(bld->elem_type, 4); |
| |
| undef = LLVMGetUndef(vec_type); |
| |
| args[0] = undef; |
| args[1] = LLVMBuildInsertElement(builder, undef, a, index0, ""); |
| args[2] = LLVMConstInt(i32t, mode, 0); |
| |
| res = lp_build_intrinsic(builder, intrinsic, |
| vec_type, args, Elements(args)); |
| |
| res = LLVMBuildExtractElement(builder, res, index0, ""); |
| } |
| else { |
| if (type.width * type.length == 128) { |
| switch(type.width) { |
| case 32: |
| intrinsic = "llvm.x86.sse41.round.ps"; |
| break; |
| case 64: |
| intrinsic = "llvm.x86.sse41.round.pd"; |
| break; |
| default: |
| assert(0); |
| return bld->undef; |
| } |
| } |
| else { |
| assert(type.width * type.length == 256); |
| assert(util_cpu_caps.has_avx); |
| |
| switch(type.width) { |
| case 32: |
| intrinsic = "llvm.x86.avx.round.ps.256"; |
| break; |
| case 64: |
| intrinsic = "llvm.x86.avx.round.pd.256"; |
| break; |
| default: |
| assert(0); |
| return bld->undef; |
| } |
| } |
| |
| res = lp_build_intrinsic_binary(builder, intrinsic, |
| bld->vec_type, a, |
| LLVMConstInt(i32t, mode, 0)); |
| } |
| |
| return res; |
| } |
| |
| |
| static INLINE LLVMValueRef |
| lp_build_iround_nearest_sse2(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef i32t = LLVMInt32TypeInContext(bld->gallivm->context); |
| LLVMTypeRef ret_type = lp_build_int_vec_type(bld->gallivm, type); |
| const char *intrinsic; |
| LLVMValueRef res; |
| |
| assert(type.floating); |
| /* using the double precision conversions is a bit more complicated */ |
| assert(type.width == 32); |
| |
| assert(lp_check_value(type, a)); |
| assert(util_cpu_caps.has_sse2); |
| |
| /* This is relying on MXCSR rounding mode, which should always be nearest. */ |
| if (type.length == 1) { |
| LLVMTypeRef vec_type; |
| LLVMValueRef undef; |
| LLVMValueRef arg; |
| LLVMValueRef index0 = LLVMConstInt(i32t, 0, 0); |
| |
| vec_type = LLVMVectorType(bld->elem_type, 4); |
| |
| intrinsic = "llvm.x86.sse.cvtss2si"; |
| |
| undef = LLVMGetUndef(vec_type); |
| |
| arg = LLVMBuildInsertElement(builder, undef, a, index0, ""); |
| |
| res = lp_build_intrinsic_unary(builder, intrinsic, |
| ret_type, arg); |
| } |
| else { |
| if (type.width* type.length == 128) { |
| intrinsic = "llvm.x86.sse2.cvtps2dq"; |
| } |
| else { |
| assert(type.width*type.length == 256); |
| assert(util_cpu_caps.has_avx); |
| |
| intrinsic = "llvm.x86.avx.cvt.ps2dq.256"; |
| } |
| res = lp_build_intrinsic_unary(builder, intrinsic, |
| ret_type, a); |
| } |
| |
| return res; |
| } |
| |
| |
| /** |
| * Return the integer part of a float (vector) value (== round toward zero). |
| * The returned value is a float (vector). |
| * Ex: trunc(-1.5) = -1.0 |
| */ |
| LLVMValueRef |
| lp_build_trunc(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| if (sse41_rounding_available(type)) { |
| return lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_TRUNCATE); |
| } |
| else { |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMTypeRef int_vec_type = lp_build_int_vec_type(bld->gallivm, type); |
| LLVMValueRef res; |
| res = LLVMBuildFPToSI(builder, a, int_vec_type, ""); |
| res = LLVMBuildSIToFP(builder, res, vec_type, ""); |
| return res; |
| } |
| } |
| |
| |
| /** |
| * Return float (vector) rounded to nearest integer (vector). The returned |
| * value is a float (vector). |
| * Ex: round(0.9) = 1.0 |
| * Ex: round(-1.5) = -2.0 |
| */ |
| LLVMValueRef |
| lp_build_round(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| if (sse41_rounding_available(type)) { |
| return lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_NEAREST); |
| } |
| else { |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMValueRef res; |
| res = lp_build_iround(bld, a); |
| res = LLVMBuildSIToFP(builder, res, vec_type, ""); |
| return res; |
| } |
| } |
| |
| |
| /** |
| * Return floor of float (vector), result is a float (vector) |
| * Ex: floor(1.1) = 1.0 |
| * Ex: floor(-1.1) = -2.0 |
| */ |
| LLVMValueRef |
| lp_build_floor(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| if (sse41_rounding_available(type)) { |
| return lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_FLOOR); |
| } |
| else { |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMValueRef res; |
| res = lp_build_ifloor(bld, a); |
| res = LLVMBuildSIToFP(builder, res, vec_type, ""); |
| return res; |
| } |
| } |
| |
| |
| /** |
| * Return ceiling of float (vector), returning float (vector). |
| * Ex: ceil( 1.1) = 2.0 |
| * Ex: ceil(-1.1) = -1.0 |
| */ |
| LLVMValueRef |
| lp_build_ceil(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| if (sse41_rounding_available(type)) { |
| return lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_CEIL); |
| } |
| else { |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMValueRef res; |
| res = lp_build_iceil(bld, a); |
| res = LLVMBuildSIToFP(builder, res, vec_type, ""); |
| return res; |
| } |
| } |
| |
| |
| /** |
| * Return fractional part of 'a' computed as a - floor(a) |
| * Typically used in texture coord arithmetic. |
| */ |
| LLVMValueRef |
| lp_build_fract(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| assert(bld->type.floating); |
| return lp_build_sub(bld, a, lp_build_floor(bld, a)); |
| } |
| |
| |
| /** |
| * Prevent returning a fractional part of 1.0 for very small negative values of |
| * 'a' by clamping against 0.99999(9). |
| */ |
| static inline LLVMValueRef |
| clamp_fract(struct lp_build_context *bld, LLVMValueRef fract) |
| { |
| LLVMValueRef max; |
| |
| /* this is the largest number smaller than 1.0 representable as float */ |
| max = lp_build_const_vec(bld->gallivm, bld->type, |
| 1.0 - 1.0/(1LL << (lp_mantissa(bld->type) + 1))); |
| return lp_build_min(bld, fract, max); |
| } |
| |
| |
| /** |
| * Same as lp_build_fract, but guarantees that the result is always smaller |
| * than one. |
| */ |
| LLVMValueRef |
| lp_build_fract_safe(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| return clamp_fract(bld, lp_build_fract(bld, a)); |
| } |
| |
| |
| /** |
| * Return the integer part of a float (vector) value (== round toward zero). |
| * The returned value is an integer (vector). |
| * Ex: itrunc(-1.5) = -1 |
| */ |
| LLVMValueRef |
| lp_build_itrunc(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef int_vec_type = lp_build_int_vec_type(bld->gallivm, type); |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| return LLVMBuildFPToSI(builder, a, int_vec_type, ""); |
| } |
| |
| |
| /** |
| * Return float (vector) rounded to nearest integer (vector). The returned |
| * value is an integer (vector). |
| * Ex: iround(0.9) = 1 |
| * Ex: iround(-1.5) = -2 |
| */ |
| LLVMValueRef |
| lp_build_iround(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef int_vec_type = bld->int_vec_type; |
| LLVMValueRef res; |
| |
| assert(type.floating); |
| |
| assert(lp_check_value(type, a)); |
| |
| if ((util_cpu_caps.has_sse2 && |
| ((type.width == 32) && (type.length == 1 || type.length == 4))) || |
| (util_cpu_caps.has_avx && type.width == 32 && type.length == 8)) { |
| return lp_build_iround_nearest_sse2(bld, a); |
| } |
| if (sse41_rounding_available(type)) { |
| res = lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_NEAREST); |
| } |
| else { |
| LLVMValueRef half; |
| |
| half = lp_build_const_vec(bld->gallivm, type, 0.5); |
| |
| if (type.sign) { |
| LLVMTypeRef vec_type = bld->vec_type; |
| LLVMValueRef mask = lp_build_const_int_vec(bld->gallivm, type, |
| (unsigned long long)1 << (type.width - 1)); |
| LLVMValueRef sign; |
| |
| /* get sign bit */ |
| sign = LLVMBuildBitCast(builder, a, int_vec_type, ""); |
| sign = LLVMBuildAnd(builder, sign, mask, ""); |
| |
| /* sign * 0.5 */ |
| half = LLVMBuildBitCast(builder, half, int_vec_type, ""); |
| half = LLVMBuildOr(builder, sign, half, ""); |
| half = LLVMBuildBitCast(builder, half, vec_type, ""); |
| } |
| |
| res = LLVMBuildFAdd(builder, a, half, ""); |
| } |
| |
| res = LLVMBuildFPToSI(builder, res, int_vec_type, ""); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Return floor of float (vector), result is an int (vector) |
| * Ex: ifloor(1.1) = 1.0 |
| * Ex: ifloor(-1.1) = -2.0 |
| */ |
| LLVMValueRef |
| lp_build_ifloor(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef int_vec_type = bld->int_vec_type; |
| LLVMValueRef res; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| res = a; |
| if (type.sign) { |
| if (sse41_rounding_available(type)) { |
| res = lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_FLOOR); |
| } |
| else { |
| /* Take the sign bit and add it to 1 constant */ |
| LLVMTypeRef vec_type = bld->vec_type; |
| unsigned mantissa = lp_mantissa(type); |
| LLVMValueRef mask = lp_build_const_int_vec(bld->gallivm, type, |
| (unsigned long long)1 << (type.width - 1)); |
| LLVMValueRef sign; |
| LLVMValueRef offset; |
| |
| /* sign = a < 0 ? ~0 : 0 */ |
| sign = LLVMBuildBitCast(builder, a, int_vec_type, ""); |
| sign = LLVMBuildAnd(builder, sign, mask, ""); |
| sign = LLVMBuildAShr(builder, sign, |
| lp_build_const_int_vec(bld->gallivm, type, |
| type.width - 1), |
| "ifloor.sign"); |
| |
| /* offset = -0.99999(9)f */ |
| offset = lp_build_const_vec(bld->gallivm, type, |
| -(double)(((unsigned long long)1 << mantissa) - 10)/((unsigned long long)1 << mantissa)); |
| offset = LLVMConstBitCast(offset, int_vec_type); |
| |
| /* offset = a < 0 ? offset : 0.0f */ |
| offset = LLVMBuildAnd(builder, offset, sign, ""); |
| offset = LLVMBuildBitCast(builder, offset, vec_type, "ifloor.offset"); |
| |
| res = LLVMBuildFAdd(builder, res, offset, "ifloor.res"); |
| } |
| } |
| |
| /* round to nearest (toward zero) */ |
| res = LLVMBuildFPToSI(builder, res, int_vec_type, "ifloor.res"); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Return ceiling of float (vector), returning int (vector). |
| * Ex: iceil( 1.1) = 2 |
| * Ex: iceil(-1.1) = -1 |
| */ |
| LLVMValueRef |
| lp_build_iceil(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef int_vec_type = bld->int_vec_type; |
| LLVMValueRef res; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| if (sse41_rounding_available(type)) { |
| res = lp_build_round_sse41(bld, a, LP_BUILD_ROUND_SSE41_CEIL); |
| } |
| else { |
| LLVMTypeRef vec_type = bld->vec_type; |
| unsigned mantissa = lp_mantissa(type); |
| LLVMValueRef offset; |
| |
| /* offset = 0.99999(9)f */ |
| offset = lp_build_const_vec(bld->gallivm, type, |
| (double)(((unsigned long long)1 << mantissa) - 10)/((unsigned long long)1 << mantissa)); |
| |
| if (type.sign) { |
| LLVMValueRef mask = lp_build_const_int_vec(bld->gallivm, type, |
| (unsigned long long)1 << (type.width - 1)); |
| LLVMValueRef sign; |
| |
| /* sign = a < 0 ? 0 : ~0 */ |
| sign = LLVMBuildBitCast(builder, a, int_vec_type, ""); |
| sign = LLVMBuildAnd(builder, sign, mask, ""); |
| sign = LLVMBuildAShr(builder, sign, |
| lp_build_const_int_vec(bld->gallivm, type, |
| type.width - 1), |
| "iceil.sign"); |
| sign = LLVMBuildNot(builder, sign, "iceil.not"); |
| |
| /* offset = a < 0 ? 0.0 : offset */ |
| offset = LLVMConstBitCast(offset, int_vec_type); |
| offset = LLVMBuildAnd(builder, offset, sign, ""); |
| offset = LLVMBuildBitCast(builder, offset, vec_type, "iceil.offset"); |
| } |
| |
| res = LLVMBuildFAdd(builder, a, offset, "iceil.res"); |
| } |
| |
| /* round to nearest (toward zero) */ |
| res = LLVMBuildFPToSI(builder, res, int_vec_type, "iceil.res"); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Combined ifloor() & fract(). |
| * |
| * Preferred to calling the functions separately, as it will ensure that the |
| * strategy (floor() vs ifloor()) that results in less redundant work is used. |
| */ |
| void |
| lp_build_ifloor_fract(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef *out_ipart, |
| LLVMValueRef *out_fpart) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMValueRef ipart; |
| |
| assert(type.floating); |
| assert(lp_check_value(type, a)); |
| |
| if (sse41_rounding_available(type)) { |
| /* |
| * floor() is easier. |
| */ |
| |
| ipart = lp_build_floor(bld, a); |
| *out_fpart = LLVMBuildFSub(builder, a, ipart, "fpart"); |
| *out_ipart = LLVMBuildFPToSI(builder, ipart, bld->int_vec_type, "ipart"); |
| } |
| else { |
| /* |
| * ifloor() is easier. |
| */ |
| |
| *out_ipart = lp_build_ifloor(bld, a); |
| ipart = LLVMBuildSIToFP(builder, *out_ipart, bld->vec_type, "ipart"); |
| *out_fpart = LLVMBuildFSub(builder, a, ipart, "fpart"); |
| } |
| } |
| |
| |
| /** |
| * Same as lp_build_ifloor_fract, but guarantees that the fractional part is |
| * always smaller than one. |
| */ |
| void |
| lp_build_ifloor_fract_safe(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef *out_ipart, |
| LLVMValueRef *out_fpart) |
| { |
| lp_build_ifloor_fract(bld, a, out_ipart, out_fpart); |
| *out_fpart = clamp_fract(bld, *out_fpart); |
| } |
| |
| |
| LLVMValueRef |
| lp_build_sqrt(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| char intrinsic[32]; |
| |
| assert(lp_check_value(type, a)); |
| |
| /* TODO: optimize the constant case */ |
| |
| assert(type.floating); |
| if (type.length == 1) { |
| util_snprintf(intrinsic, sizeof intrinsic, "llvm.sqrt.f%u", type.width); |
| } |
| else { |
| util_snprintf(intrinsic, sizeof intrinsic, "llvm.sqrt.v%uf%u", type.length, type.width); |
| } |
| |
| return lp_build_intrinsic_unary(builder, intrinsic, vec_type, a); |
| } |
| |
| |
| /** |
| * Do one Newton-Raphson step to improve reciprocate precision: |
| * |
| * x_{i+1} = x_i * (2 - a * x_i) |
| * |
| * XXX: Unfortunately this won't give IEEE-754 conformant results for 0 or |
| * +/-Inf, giving NaN instead. Certain applications rely on this behavior, |
| * such as Google Earth, which does RCP(RSQRT(0.0) when drawing the Earth's |
| * halo. It would be necessary to clamp the argument to prevent this. |
| * |
| * See also: |
| * - http://en.wikipedia.org/wiki/Division_(digital)#Newton.E2.80.93Raphson_division |
| * - http://softwarecommunity.intel.com/articles/eng/1818.htm |
| */ |
| static INLINE LLVMValueRef |
| lp_build_rcp_refine(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef rcp_a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef two = lp_build_const_vec(bld->gallivm, bld->type, 2.0); |
| LLVMValueRef res; |
| |
| res = LLVMBuildFMul(builder, a, rcp_a, ""); |
| res = LLVMBuildFSub(builder, two, res, ""); |
| res = LLVMBuildFMul(builder, rcp_a, res, ""); |
| |
| return res; |
| } |
| |
| |
| LLVMValueRef |
| lp_build_rcp(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(lp_check_value(type, a)); |
| |
| if(a == bld->zero) |
| return bld->undef; |
| if(a == bld->one) |
| return bld->one; |
| if(a == bld->undef) |
| return bld->undef; |
| |
| assert(type.floating); |
| |
| if(LLVMIsConstant(a)) |
| return LLVMConstFDiv(bld->one, a); |
| |
| /* |
| * We don't use RCPPS because: |
| * - it only has 10bits of precision |
| * - it doesn't even get the reciprocate of 1.0 exactly |
| * - doing Newton-Rapshon steps yields wrong (NaN) values for 0.0 or Inf |
| * - for recent processors the benefit over DIVPS is marginal, a case |
| * dependent |
| * |
| * We could still use it on certain processors if benchmarks show that the |
| * RCPPS plus necessary workarounds are still preferrable to DIVPS; or for |
| * particular uses that require less workarounds. |
| */ |
| |
| if (FALSE && ((util_cpu_caps.has_sse && type.width == 32 && type.length == 4) || |
| (util_cpu_caps.has_avx && type.width == 32 && type.length == 8))){ |
| const unsigned num_iterations = 0; |
| LLVMValueRef res; |
| unsigned i; |
| const char *intrinsic = NULL; |
| |
| if (type.length == 4) { |
| intrinsic = "llvm.x86.sse.rcp.ps"; |
| } |
| else { |
| intrinsic = "llvm.x86.avx.rcp.ps.256"; |
| } |
| |
| res = lp_build_intrinsic_unary(builder, intrinsic, bld->vec_type, a); |
| |
| for (i = 0; i < num_iterations; ++i) { |
| res = lp_build_rcp_refine(bld, a, res); |
| } |
| |
| return res; |
| } |
| |
| return LLVMBuildFDiv(builder, bld->one, a, ""); |
| } |
| |
| |
| /** |
| * Do one Newton-Raphson step to improve rsqrt precision: |
| * |
| * x_{i+1} = 0.5 * x_i * (3.0 - a * x_i * x_i) |
| * |
| * See also: |
| * - http://softwarecommunity.intel.com/articles/eng/1818.htm |
| */ |
| static INLINE LLVMValueRef |
| lp_build_rsqrt_refine(struct lp_build_context *bld, |
| LLVMValueRef a, |
| LLVMValueRef rsqrt_a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef half = lp_build_const_vec(bld->gallivm, bld->type, 0.5); |
| LLVMValueRef three = lp_build_const_vec(bld->gallivm, bld->type, 3.0); |
| LLVMValueRef res; |
| |
| res = LLVMBuildFMul(builder, rsqrt_a, rsqrt_a, ""); |
| res = LLVMBuildFMul(builder, a, res, ""); |
| res = LLVMBuildFSub(builder, three, res, ""); |
| res = LLVMBuildFMul(builder, rsqrt_a, res, ""); |
| res = LLVMBuildFMul(builder, half, res, ""); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Generate 1/sqrt(a) |
| */ |
| LLVMValueRef |
| lp_build_rsqrt(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| |
| assert(lp_check_value(type, a)); |
| |
| assert(type.floating); |
| |
| if ((util_cpu_caps.has_sse && type.width == 32 && type.length == 4) || |
| (util_cpu_caps.has_avx && type.width == 32 && type.length == 8)) { |
| const unsigned num_iterations = 1; |
| LLVMValueRef res; |
| unsigned i; |
| const char *intrinsic = NULL; |
| |
| if (type.length == 4) { |
| intrinsic = "llvm.x86.sse.rsqrt.ps"; |
| } |
| else { |
| intrinsic = "llvm.x86.avx.rsqrt.ps.256"; |
| } |
| |
| res = lp_build_intrinsic_unary(builder, intrinsic, bld->vec_type, a); |
| |
| |
| for (i = 0; i < num_iterations; ++i) { |
| res = lp_build_rsqrt_refine(bld, a, res); |
| } |
| |
| return res; |
| } |
| |
| return lp_build_rcp(bld, lp_build_sqrt(bld, a)); |
| } |
| |
| |
| /** |
| * Generate sin(a) using SSE2 |
| */ |
| LLVMValueRef |
| lp_build_sin(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| struct gallivm_state *gallivm = bld->gallivm; |
| LLVMBuilderRef builder = gallivm->builder; |
| struct lp_type int_type = lp_int_type(bld->type); |
| LLVMBuilderRef b = builder; |
| |
| /* |
| * take the absolute value, |
| * x = _mm_and_ps(x, *(v4sf*)_ps_inv_sign_mask); |
| */ |
| |
| LLVMValueRef inv_sig_mask = lp_build_const_int_vec(gallivm, bld->type, ~0x80000000); |
| LLVMValueRef a_v4si = LLVMBuildBitCast(b, a, bld->int_vec_type, "a_v4si"); |
| |
| LLVMValueRef absi = LLVMBuildAnd(b, a_v4si, inv_sig_mask, "absi"); |
| LLVMValueRef x_abs = LLVMBuildBitCast(b, absi, bld->vec_type, "x_abs"); |
| |
| /* |
| * extract the sign bit (upper one) |
| * sign_bit = _mm_and_ps(sign_bit, *(v4sf*)_ps_sign_mask); |
| */ |
| LLVMValueRef sig_mask = lp_build_const_int_vec(gallivm, bld->type, 0x80000000); |
| LLVMValueRef sign_bit_i = LLVMBuildAnd(b, a_v4si, sig_mask, "sign_bit_i"); |
| |
| /* |
| * scale by 4/Pi |
| * y = _mm_mul_ps(x, *(v4sf*)_ps_cephes_FOPI); |
| */ |
| |
| LLVMValueRef FOPi = lp_build_const_vec(gallivm, bld->type, 1.27323954473516); |
| LLVMValueRef scale_y = LLVMBuildFMul(b, x_abs, FOPi, "scale_y"); |
| |
| /* |
| * store the integer part of y in mm0 |
| * emm2 = _mm_cvttps_epi32(y); |
| */ |
| |
| LLVMValueRef emm2_i = LLVMBuildFPToSI(b, scale_y, bld->int_vec_type, "emm2_i"); |
| |
| /* |
| * j=(j+1) & (~1) (see the cephes sources) |
| * emm2 = _mm_add_epi32(emm2, *(v4si*)_pi32_1); |
| */ |
| |
| LLVMValueRef all_one = lp_build_const_int_vec(gallivm, bld->type, 1); |
| LLVMValueRef emm2_add = LLVMBuildAdd(b, emm2_i, all_one, "emm2_add"); |
| /* |
| * emm2 = _mm_and_si128(emm2, *(v4si*)_pi32_inv1); |
| */ |
| LLVMValueRef inv_one = lp_build_const_int_vec(gallivm, bld->type, ~1); |
| LLVMValueRef emm2_and = LLVMBuildAnd(b, emm2_add, inv_one, "emm2_and"); |
| |
| /* |
| * y = _mm_cvtepi32_ps(emm2); |
| */ |
| LLVMValueRef y_2 = LLVMBuildSIToFP(b, emm2_and, bld->vec_type, "y_2"); |
| |
| /* get the swap sign flag |
| * emm0 = _mm_and_si128(emm2, *(v4si*)_pi32_4); |
| */ |
| LLVMValueRef pi32_4 = lp_build_const_int_vec(gallivm, bld->type, 4); |
| LLVMValueRef emm0_and = LLVMBuildAnd(b, emm2_add, pi32_4, "emm0_and"); |
| |
| /* |
| * emm2 = _mm_slli_epi32(emm0, 29); |
| */ |
| LLVMValueRef const_29 = lp_build_const_int_vec(gallivm, bld->type, 29); |
| LLVMValueRef swap_sign_bit = LLVMBuildShl(b, emm0_and, const_29, "swap_sign_bit"); |
| |
| /* |
| * get the polynom selection mask |
| * there is one polynom for 0 <= x <= Pi/4 |
| * and another one for Pi/4<x<=Pi/2 |
| * Both branches will be computed. |
| * |
| * emm2 = _mm_and_si128(emm2, *(v4si*)_pi32_2); |
| * emm2 = _mm_cmpeq_epi32(emm2, _mm_setzero_si128()); |
| */ |
| |
| LLVMValueRef pi32_2 = lp_build_const_int_vec(gallivm, bld->type, 2); |
| LLVMValueRef emm2_3 = LLVMBuildAnd(b, emm2_and, pi32_2, "emm2_3"); |
| LLVMValueRef poly_mask = lp_build_compare(gallivm, |
| int_type, PIPE_FUNC_EQUAL, |
| emm2_3, lp_build_const_int_vec(gallivm, bld->type, 0)); |
| /* |
| * sign_bit = _mm_xor_ps(sign_bit, swap_sign_bit); |
| */ |
| LLVMValueRef sign_bit_1 = LLVMBuildXor(b, sign_bit_i, swap_sign_bit, "sign_bit"); |
| |
| /* |
| * _PS_CONST(minus_cephes_DP1, -0.78515625); |
| * _PS_CONST(minus_cephes_DP2, -2.4187564849853515625e-4); |
| * _PS_CONST(minus_cephes_DP3, -3.77489497744594108e-8); |
| */ |
| LLVMValueRef DP1 = lp_build_const_vec(gallivm, bld->type, -0.78515625); |
| LLVMValueRef DP2 = lp_build_const_vec(gallivm, bld->type, -2.4187564849853515625e-4); |
| LLVMValueRef DP3 = lp_build_const_vec(gallivm, bld->type, -3.77489497744594108e-8); |
| |
| /* |
| * The magic pass: "Extended precision modular arithmetic" |
| * x = ((x - y * DP1) - y * DP2) - y * DP3; |
| * xmm1 = _mm_mul_ps(y, xmm1); |
| * xmm2 = _mm_mul_ps(y, xmm2); |
| * xmm3 = _mm_mul_ps(y, xmm3); |
| */ |
| LLVMValueRef xmm1 = LLVMBuildFMul(b, y_2, DP1, "xmm1"); |
| LLVMValueRef xmm2 = LLVMBuildFMul(b, y_2, DP2, "xmm2"); |
| LLVMValueRef xmm3 = LLVMBuildFMul(b, y_2, DP3, "xmm3"); |
| |
| /* |
| * x = _mm_add_ps(x, xmm1); |
| * x = _mm_add_ps(x, xmm2); |
| * x = _mm_add_ps(x, xmm3); |
| */ |
| |
| LLVMValueRef x_1 = LLVMBuildFAdd(b, x_abs, xmm1, "x_1"); |
| LLVMValueRef x_2 = LLVMBuildFAdd(b, x_1, xmm2, "x_2"); |
| LLVMValueRef x_3 = LLVMBuildFAdd(b, x_2, xmm3, "x_3"); |
| |
| /* |
| * Evaluate the first polynom (0 <= x <= Pi/4) |
| * |
| * z = _mm_mul_ps(x,x); |
| */ |
| LLVMValueRef z = LLVMBuildFMul(b, x_3, x_3, "z"); |
| |
| /* |
| * _PS_CONST(coscof_p0, 2.443315711809948E-005); |
| * _PS_CONST(coscof_p1, -1.388731625493765E-003); |
| * _PS_CONST(coscof_p2, 4.166664568298827E-002); |
| */ |
| LLVMValueRef coscof_p0 = lp_build_const_vec(gallivm, bld->type, 2.443315711809948E-005); |
| LLVMValueRef coscof_p1 = lp_build_const_vec(gallivm, bld->type, -1.388731625493765E-003); |
| LLVMValueRef coscof_p2 = lp_build_const_vec(gallivm, bld->type, 4.166664568298827E-002); |
| |
| /* |
| * y = *(v4sf*)_ps_coscof_p0; |
| * y = _mm_mul_ps(y, z); |
| */ |
| LLVMValueRef y_3 = LLVMBuildFMul(b, z, coscof_p0, "y_3"); |
| LLVMValueRef y_4 = LLVMBuildFAdd(b, y_3, coscof_p1, "y_4"); |
| LLVMValueRef y_5 = LLVMBuildFMul(b, y_4, z, "y_5"); |
| LLVMValueRef y_6 = LLVMBuildFAdd(b, y_5, coscof_p2, "y_6"); |
| LLVMValueRef y_7 = LLVMBuildFMul(b, y_6, z, "y_7"); |
| LLVMValueRef y_8 = LLVMBuildFMul(b, y_7, z, "y_8"); |
| |
| |
| /* |
| * tmp = _mm_mul_ps(z, *(v4sf*)_ps_0p5); |
| * y = _mm_sub_ps(y, tmp); |
| * y = _mm_add_ps(y, *(v4sf*)_ps_1); |
| */ |
| LLVMValueRef half = lp_build_const_vec(gallivm, bld->type, 0.5); |
| LLVMValueRef tmp = LLVMBuildFMul(b, z, half, "tmp"); |
| LLVMValueRef y_9 = LLVMBuildFSub(b, y_8, tmp, "y_8"); |
| LLVMValueRef one = lp_build_const_vec(gallivm, bld->type, 1.0); |
| LLVMValueRef y_10 = LLVMBuildFAdd(b, y_9, one, "y_9"); |
| |
| /* |
| * _PS_CONST(sincof_p0, -1.9515295891E-4); |
| * _PS_CONST(sincof_p1, 8.3321608736E-3); |
| * _PS_CONST(sincof_p2, -1.6666654611E-1); |
| */ |
| LLVMValueRef sincof_p0 = lp_build_const_vec(gallivm, bld->type, -1.9515295891E-4); |
| LLVMValueRef sincof_p1 = lp_build_const_vec(gallivm, bld->type, 8.3321608736E-3); |
| LLVMValueRef sincof_p2 = lp_build_const_vec(gallivm, bld->type, -1.6666654611E-1); |
| |
| /* |
| * Evaluate the second polynom (Pi/4 <= x <= 0) |
| * |
| * y2 = *(v4sf*)_ps_sincof_p0; |
| * y2 = _mm_mul_ps(y2, z); |
| * y2 = _mm_add_ps(y2, *(v4sf*)_ps_sincof_p1); |
| * y2 = _mm_mul_ps(y2, z); |
| * y2 = _mm_add_ps(y2, *(v4sf*)_ps_sincof_p2); |
| * y2 = _mm_mul_ps(y2, z); |
| * y2 = _mm_mul_ps(y2, x); |
| * y2 = _mm_add_ps(y2, x); |
| */ |
| |
| LLVMValueRef y2_3 = LLVMBuildFMul(b, z, sincof_p0, "y2_3"); |
| LLVMValueRef y2_4 = LLVMBuildFAdd(b, y2_3, sincof_p1, "y2_4"); |
| LLVMValueRef y2_5 = LLVMBuildFMul(b, y2_4, z, "y2_5"); |
| LLVMValueRef y2_6 = LLVMBuildFAdd(b, y2_5, sincof_p2, "y2_6"); |
| LLVMValueRef y2_7 = LLVMBuildFMul(b, y2_6, z, "y2_7"); |
| LLVMValueRef y2_8 = LLVMBuildFMul(b, y2_7, x_3, "y2_8"); |
| LLVMValueRef y2_9 = LLVMBuildFAdd(b, y2_8, x_3, "y2_9"); |
| |
| /* |
| * select the correct result from the two polynoms |
| * xmm3 = poly_mask; |
| * y2 = _mm_and_ps(xmm3, y2); //, xmm3); |
| * y = _mm_andnot_ps(xmm3, y); |
| * y = _mm_add_ps(y,y2); |
| */ |
| LLVMValueRef y2_i = LLVMBuildBitCast(b, y2_9, bld->int_vec_type, "y2_i"); |
| LLVMValueRef y_i = LLVMBuildBitCast(b, y_10, bld->int_vec_type, "y_i"); |
| LLVMValueRef y2_and = LLVMBuildAnd(b, y2_i, poly_mask, "y2_and"); |
| LLVMValueRef inv = lp_build_const_int_vec(gallivm, bld->type, ~0); |
| LLVMValueRef poly_mask_inv = LLVMBuildXor(b, poly_mask, inv, "poly_mask_inv"); |
| LLVMValueRef y_and = LLVMBuildAnd(b, y_i, poly_mask_inv, "y_and"); |
| LLVMValueRef y_combine = LLVMBuildAdd(b, y_and, y2_and, "y_combine"); |
| |
| /* |
| * update the sign |
| * y = _mm_xor_ps(y, sign_bit); |
| */ |
| LLVMValueRef y_sign = LLVMBuildXor(b, y_combine, sign_bit_1, "y_sin"); |
| LLVMValueRef y_result = LLVMBuildBitCast(b, y_sign, bld->vec_type, "y_result"); |
| return y_result; |
| } |
| |
| |
| /** |
| * Generate cos(a) using SSE2 |
| */ |
| LLVMValueRef |
| lp_build_cos(struct lp_build_context *bld, |
| LLVMValueRef a) |
| { |
| struct gallivm_state *gallivm = bld->gallivm; |
| LLVMBuilderRef builder = gallivm->builder; |
| struct lp_type int_type = lp_int_type(bld->type); |
| LLVMBuilderRef b = builder; |
| |
| /* |
| * take the absolute value, |
| * x = _mm_and_ps(x, *(v4sf*)_ps_inv_sign_mask); |
| */ |
| |
| LLVMValueRef inv_sig_mask = lp_build_const_int_vec(gallivm, bld->type, ~0x80000000); |
| LLVMValueRef a_v4si = LLVMBuildBitCast(b, a, bld->int_vec_type, "a_v4si"); |
| |
| LLVMValueRef absi = LLVMBuildAnd(b, a_v4si, inv_sig_mask, "absi"); |
| LLVMValueRef x_abs = LLVMBuildBitCast(b, absi, bld->vec_type, "x_abs"); |
| |
| /* |
| * scale by 4/Pi |
| * y = _mm_mul_ps(x, *(v4sf*)_ps_cephes_FOPI); |
| */ |
| |
| LLVMValueRef FOPi = lp_build_const_vec(gallivm, bld->type, 1.27323954473516); |
| LLVMValueRef scale_y = LLVMBuildFMul(b, x_abs, FOPi, "scale_y"); |
| |
| /* |
| * store the integer part of y in mm0 |
| * emm2 = _mm_cvttps_epi32(y); |
| */ |
| |
| LLVMValueRef emm2_i = LLVMBuildFPToSI(b, scale_y, bld->int_vec_type, "emm2_i"); |
| |
| /* |
| * j=(j+1) & (~1) (see the cephes sources) |
| * emm2 = _mm_add_epi32(emm2, *(v4si*)_pi32_1); |
| */ |
| |
| LLVMValueRef all_one = lp_build_const_int_vec(gallivm, bld->type, 1); |
| LLVMValueRef emm2_add = LLVMBuildAdd(b, emm2_i, all_one, "emm2_add"); |
| /* |
| * emm2 = _mm_and_si128(emm2, *(v4si*)_pi32_inv1); |
| */ |
| LLVMValueRef inv_one = lp_build_const_int_vec(gallivm, bld->type, ~1); |
| LLVMValueRef emm2_and = LLVMBuildAnd(b, emm2_add, inv_one, "emm2_and"); |
| |
| /* |
| * y = _mm_cvtepi32_ps(emm2); |
| */ |
| LLVMValueRef y_2 = LLVMBuildSIToFP(b, emm2_and, bld->vec_type, "y_2"); |
| |
| |
| /* |
| * emm2 = _mm_sub_epi32(emm2, *(v4si*)_pi32_2); |
| */ |
| LLVMValueRef const_2 = lp_build_const_int_vec(gallivm, bld->type, 2); |
| LLVMValueRef emm2_2 = LLVMBuildSub(b, emm2_and, const_2, "emm2_2"); |
| |
| |
| /* get the swap sign flag |
| * emm0 = _mm_andnot_si128(emm2, *(v4si*)_pi32_4); |
| */ |
| LLVMValueRef inv = lp_build_const_int_vec(gallivm, bld->type, ~0); |
| LLVMValueRef emm0_not = LLVMBuildXor(b, emm2_2, inv, "emm0_not"); |
| LLVMValueRef pi32_4 = lp_build_const_int_vec(gallivm, bld->type, 4); |
| LLVMValueRef emm0_and = LLVMBuildAnd(b, emm0_not, pi32_4, "emm0_and"); |
| |
| /* |
| * emm2 = _mm_slli_epi32(emm0, 29); |
| */ |
| LLVMValueRef const_29 = lp_build_const_int_vec(gallivm, bld->type, 29); |
| LLVMValueRef sign_bit = LLVMBuildShl(b, emm0_and, const_29, "sign_bit"); |
| |
| /* |
| * get the polynom selection mask |
| * there is one polynom for 0 <= x <= Pi/4 |
| * and another one for Pi/4<x<=Pi/2 |
| * Both branches will be computed. |
| * |
| * emm2 = _mm_and_si128(emm2, *(v4si*)_pi32_2); |
| * emm2 = _mm_cmpeq_epi32(emm2, _mm_setzero_si128()); |
| */ |
| |
| LLVMValueRef pi32_2 = lp_build_const_int_vec(gallivm, bld->type, 2); |
| LLVMValueRef emm2_3 = LLVMBuildAnd(b, emm2_2, pi32_2, "emm2_3"); |
| LLVMValueRef poly_mask = lp_build_compare(gallivm, |
| int_type, PIPE_FUNC_EQUAL, |
| emm2_3, lp_build_const_int_vec(gallivm, bld->type, 0)); |
| |
| /* |
| * _PS_CONST(minus_cephes_DP1, -0.78515625); |
| * _PS_CONST(minus_cephes_DP2, -2.4187564849853515625e-4); |
| * _PS_CONST(minus_cephes_DP3, -3.77489497744594108e-8); |
| */ |
| LLVMValueRef DP1 = lp_build_const_vec(gallivm, bld->type, -0.78515625); |
| LLVMValueRef DP2 = lp_build_const_vec(gallivm, bld->type, -2.4187564849853515625e-4); |
| LLVMValueRef DP3 = lp_build_const_vec(gallivm, bld->type, -3.77489497744594108e-8); |
| |
| /* |
| * The magic pass: "Extended precision modular arithmetic" |
| * x = ((x - y * DP1) - y * DP2) - y * DP3; |
| * xmm1 = _mm_mul_ps(y, xmm1); |
| * xmm2 = _mm_mul_ps(y, xmm2); |
| * xmm3 = _mm_mul_ps(y, xmm3); |
| */ |
| LLVMValueRef xmm1 = LLVMBuildFMul(b, y_2, DP1, "xmm1"); |
| LLVMValueRef xmm2 = LLVMBuildFMul(b, y_2, DP2, "xmm2"); |
| LLVMValueRef xmm3 = LLVMBuildFMul(b, y_2, DP3, "xmm3"); |
| |
| /* |
| * x = _mm_add_ps(x, xmm1); |
| * x = _mm_add_ps(x, xmm2); |
| * x = _mm_add_ps(x, xmm3); |
| */ |
| |
| LLVMValueRef x_1 = LLVMBuildFAdd(b, x_abs, xmm1, "x_1"); |
| LLVMValueRef x_2 = LLVMBuildFAdd(b, x_1, xmm2, "x_2"); |
| LLVMValueRef x_3 = LLVMBuildFAdd(b, x_2, xmm3, "x_3"); |
| |
| /* |
| * Evaluate the first polynom (0 <= x <= Pi/4) |
| * |
| * z = _mm_mul_ps(x,x); |
| */ |
| LLVMValueRef z = LLVMBuildFMul(b, x_3, x_3, "z"); |
| |
| /* |
| * _PS_CONST(coscof_p0, 2.443315711809948E-005); |
| * _PS_CONST(coscof_p1, -1.388731625493765E-003); |
| * _PS_CONST(coscof_p2, 4.166664568298827E-002); |
| */ |
| LLVMValueRef coscof_p0 = lp_build_const_vec(gallivm, bld->type, 2.443315711809948E-005); |
| LLVMValueRef coscof_p1 = lp_build_const_vec(gallivm, bld->type, -1.388731625493765E-003); |
| LLVMValueRef coscof_p2 = lp_build_const_vec(gallivm, bld->type, 4.166664568298827E-002); |
| |
| /* |
| * y = *(v4sf*)_ps_coscof_p0; |
| * y = _mm_mul_ps(y, z); |
| */ |
| LLVMValueRef y_3 = LLVMBuildFMul(b, z, coscof_p0, "y_3"); |
| LLVMValueRef y_4 = LLVMBuildFAdd(b, y_3, coscof_p1, "y_4"); |
| LLVMValueRef y_5 = LLVMBuildFMul(b, y_4, z, "y_5"); |
| LLVMValueRef y_6 = LLVMBuildFAdd(b, y_5, coscof_p2, "y_6"); |
| LLVMValueRef y_7 = LLVMBuildFMul(b, y_6, z, "y_7"); |
| LLVMValueRef y_8 = LLVMBuildFMul(b, y_7, z, "y_8"); |
| |
| |
| /* |
| * tmp = _mm_mul_ps(z, *(v4sf*)_ps_0p5); |
| * y = _mm_sub_ps(y, tmp); |
| * y = _mm_add_ps(y, *(v4sf*)_ps_1); |
| */ |
| LLVMValueRef half = lp_build_const_vec(gallivm, bld->type, 0.5); |
| LLVMValueRef tmp = LLVMBuildFMul(b, z, half, "tmp"); |
| LLVMValueRef y_9 = LLVMBuildFSub(b, y_8, tmp, "y_8"); |
| LLVMValueRef one = lp_build_const_vec(gallivm, bld->type, 1.0); |
| LLVMValueRef y_10 = LLVMBuildFAdd(b, y_9, one, "y_9"); |
| |
| /* |
| * _PS_CONST(sincof_p0, -1.9515295891E-4); |
| * _PS_CONST(sincof_p1, 8.3321608736E-3); |
| * _PS_CONST(sincof_p2, -1.6666654611E-1); |
| */ |
| LLVMValueRef sincof_p0 = lp_build_const_vec(gallivm, bld->type, -1.9515295891E-4); |
| LLVMValueRef sincof_p1 = lp_build_const_vec(gallivm, bld->type, 8.3321608736E-3); |
| LLVMValueRef sincof_p2 = lp_build_const_vec(gallivm, bld->type, -1.6666654611E-1); |
| |
| /* |
| * Evaluate the second polynom (Pi/4 <= x <= 0) |
| * |
| * y2 = *(v4sf*)_ps_sincof_p0; |
| * y2 = _mm_mul_ps(y2, z); |
| * y2 = _mm_add_ps(y2, *(v4sf*)_ps_sincof_p1); |
| * y2 = _mm_mul_ps(y2, z); |
| * y2 = _mm_add_ps(y2, *(v4sf*)_ps_sincof_p2); |
| * y2 = _mm_mul_ps(y2, z); |
| * y2 = _mm_mul_ps(y2, x); |
| * y2 = _mm_add_ps(y2, x); |
| */ |
| |
| LLVMValueRef y2_3 = LLVMBuildFMul(b, z, sincof_p0, "y2_3"); |
| LLVMValueRef y2_4 = LLVMBuildFAdd(b, y2_3, sincof_p1, "y2_4"); |
| LLVMValueRef y2_5 = LLVMBuildFMul(b, y2_4, z, "y2_5"); |
| LLVMValueRef y2_6 = LLVMBuildFAdd(b, y2_5, sincof_p2, "y2_6"); |
| LLVMValueRef y2_7 = LLVMBuildFMul(b, y2_6, z, "y2_7"); |
| LLVMValueRef y2_8 = LLVMBuildFMul(b, y2_7, x_3, "y2_8"); |
| LLVMValueRef y2_9 = LLVMBuildFAdd(b, y2_8, x_3, "y2_9"); |
| |
| /* |
| * select the correct result from the two polynoms |
| * xmm3 = poly_mask; |
| * y2 = _mm_and_ps(xmm3, y2); //, xmm3); |
| * y = _mm_andnot_ps(xmm3, y); |
| * y = _mm_add_ps(y,y2); |
| */ |
| LLVMValueRef y2_i = LLVMBuildBitCast(b, y2_9, bld->int_vec_type, "y2_i"); |
| LLVMValueRef y_i = LLVMBuildBitCast(b, y_10, bld->int_vec_type, "y_i"); |
| LLVMValueRef y2_and = LLVMBuildAnd(b, y2_i, poly_mask, "y2_and"); |
| LLVMValueRef poly_mask_inv = LLVMBuildXor(b, poly_mask, inv, "poly_mask_inv"); |
| LLVMValueRef y_and = LLVMBuildAnd(b, y_i, poly_mask_inv, "y_and"); |
| LLVMValueRef y_combine = LLVMBuildAdd(b, y_and, y2_and, "y_combine"); |
| |
| /* |
| * update the sign |
| * y = _mm_xor_ps(y, sign_bit); |
| */ |
| LLVMValueRef y_sign = LLVMBuildXor(b, y_combine, sign_bit, "y_sin"); |
| LLVMValueRef y_result = LLVMBuildBitCast(b, y_sign, bld->vec_type, "y_result"); |
| return y_result; |
| } |
| |
| |
| /** |
| * Generate pow(x, y) |
| */ |
| LLVMValueRef |
| lp_build_pow(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef y) |
| { |
| /* TODO: optimize the constant case */ |
| if (gallivm_debug & GALLIVM_DEBUG_PERF && |
| LLVMIsConstant(x) && LLVMIsConstant(y)) { |
| debug_printf("%s: inefficient/imprecise constant arithmetic\n", |
| __FUNCTION__); |
| } |
| |
| return lp_build_exp2(bld, lp_build_mul(bld, lp_build_log2(bld, x), y)); |
| } |
| |
| |
| /** |
| * Generate exp(x) |
| */ |
| LLVMValueRef |
| lp_build_exp(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| /* log2(e) = 1/log(2) */ |
| LLVMValueRef log2e = lp_build_const_vec(bld->gallivm, bld->type, |
| 1.4426950408889634); |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| return lp_build_exp2(bld, lp_build_mul(bld, log2e, x)); |
| } |
| |
| |
| /** |
| * Generate log(x) |
| */ |
| LLVMValueRef |
| lp_build_log(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| /* log(2) */ |
| LLVMValueRef log2 = lp_build_const_vec(bld->gallivm, bld->type, |
| 0.69314718055994529); |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| return lp_build_mul(bld, log2, lp_build_log2(bld, x)); |
| } |
| |
| |
| /** |
| * Generate polynomial. |
| * Ex: coeffs[0] + x * coeffs[1] + x^2 * coeffs[2]. |
| */ |
| static LLVMValueRef |
| lp_build_polynomial(struct lp_build_context *bld, |
| LLVMValueRef x, |
| const double *coeffs, |
| unsigned num_coeffs) |
| { |
| const struct lp_type type = bld->type; |
| LLVMValueRef even = NULL, odd = NULL; |
| LLVMValueRef x2; |
| unsigned i; |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| /* TODO: optimize the constant case */ |
| if (gallivm_debug & GALLIVM_DEBUG_PERF && |
| LLVMIsConstant(x)) { |
| debug_printf("%s: inefficient/imprecise constant arithmetic\n", |
| __FUNCTION__); |
| } |
| |
| /* |
| * Calculate odd and even terms seperately to decrease data dependency |
| * Ex: |
| * c[0] + x^2 * c[2] + x^4 * c[4] ... |
| * + x * (c[1] + x^2 * c[3] + x^4 * c[5]) ... |
| */ |
| x2 = lp_build_mul(bld, x, x); |
| |
| for (i = num_coeffs; i--; ) { |
| LLVMValueRef coeff; |
| |
| coeff = lp_build_const_vec(bld->gallivm, type, coeffs[i]); |
| |
| if (i % 2 == 0) { |
| if (even) |
| even = lp_build_add(bld, coeff, lp_build_mul(bld, x2, even)); |
| else |
| even = coeff; |
| } else { |
| if (odd) |
| odd = lp_build_add(bld, coeff, lp_build_mul(bld, x2, odd)); |
| else |
| odd = coeff; |
| } |
| } |
| |
| if (odd) |
| return lp_build_add(bld, lp_build_mul(bld, odd, x), even); |
| else if (even) |
| return even; |
| else |
| return bld->undef; |
| } |
| |
| |
| /** |
| * Minimax polynomial fit of 2**x, in range [0, 1[ |
| */ |
| const double lp_build_exp2_polynomial[] = { |
| #if EXP_POLY_DEGREE == 5 |
| 0.999999925063526176901, |
| 0.693153073200168932794, |
| 0.240153617044375388211, |
| 0.0558263180532956664775, |
| 0.00898934009049466391101, |
| 0.00187757667519147912699 |
| #elif EXP_POLY_DEGREE == 4 |
| 1.00000259337069434683, |
| 0.693003834469974940458, |
| 0.24144275689150793076, |
| 0.0520114606103070150235, |
| 0.0135341679161270268764 |
| #elif EXP_POLY_DEGREE == 3 |
| 0.999925218562710312959, |
| 0.695833540494823811697, |
| 0.226067155427249155588, |
| 0.0780245226406372992967 |
| #elif EXP_POLY_DEGREE == 2 |
| 1.00172476321474503578, |
| 0.657636275736077639316, |
| 0.33718943461968720704 |
| #else |
| #error |
| #endif |
| }; |
| |
| |
| void |
| lp_build_exp2_approx(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef *p_exp2_int_part, |
| LLVMValueRef *p_frac_part, |
| LLVMValueRef *p_exp2) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMValueRef ipart = NULL; |
| LLVMValueRef fpart = NULL; |
| LLVMValueRef expipart = NULL; |
| LLVMValueRef expfpart = NULL; |
| LLVMValueRef res = NULL; |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| if(p_exp2_int_part || p_frac_part || p_exp2) { |
| /* TODO: optimize the constant case */ |
| if (gallivm_debug & GALLIVM_DEBUG_PERF && |
| LLVMIsConstant(x)) { |
| debug_printf("%s: inefficient/imprecise constant arithmetic\n", |
| __FUNCTION__); |
| } |
| |
| assert(type.floating && type.width == 32); |
| |
| x = lp_build_min(bld, x, lp_build_const_vec(bld->gallivm, type, 129.0)); |
| x = lp_build_max(bld, x, lp_build_const_vec(bld->gallivm, type, -126.99999)); |
| |
| /* ipart = floor(x) */ |
| /* fpart = x - ipart */ |
| lp_build_ifloor_fract(bld, x, &ipart, &fpart); |
| } |
| |
| if(p_exp2_int_part || p_exp2) { |
| /* expipart = (float) (1 << ipart) */ |
| expipart = LLVMBuildAdd(builder, ipart, |
| lp_build_const_int_vec(bld->gallivm, type, 127), ""); |
| expipart = LLVMBuildShl(builder, expipart, |
| lp_build_const_int_vec(bld->gallivm, type, 23), ""); |
| expipart = LLVMBuildBitCast(builder, expipart, vec_type, ""); |
| } |
| |
| if(p_exp2) { |
| expfpart = lp_build_polynomial(bld, fpart, lp_build_exp2_polynomial, |
| Elements(lp_build_exp2_polynomial)); |
| |
| res = LLVMBuildFMul(builder, expipart, expfpart, ""); |
| } |
| |
| if(p_exp2_int_part) |
| *p_exp2_int_part = expipart; |
| |
| if(p_frac_part) |
| *p_frac_part = fpart; |
| |
| if(p_exp2) |
| *p_exp2 = res; |
| } |
| |
| |
| LLVMValueRef |
| lp_build_exp2(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| LLVMValueRef res; |
| lp_build_exp2_approx(bld, x, NULL, NULL, &res); |
| return res; |
| } |
| |
| |
| /** |
| * Extract the exponent of a IEEE-754 floating point value. |
| * |
| * Optionally apply an integer bias. |
| * |
| * Result is an integer value with |
| * |
| * ifloor(log2(x)) + bias |
| */ |
| LLVMValueRef |
| lp_build_extract_exponent(struct lp_build_context *bld, |
| LLVMValueRef x, |
| int bias) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| unsigned mantissa = lp_mantissa(type); |
| LLVMValueRef res; |
| |
| assert(type.floating); |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| x = LLVMBuildBitCast(builder, x, bld->int_vec_type, ""); |
| |
| res = LLVMBuildLShr(builder, x, |
| lp_build_const_int_vec(bld->gallivm, type, mantissa), ""); |
| res = LLVMBuildAnd(builder, res, |
| lp_build_const_int_vec(bld->gallivm, type, 255), ""); |
| res = LLVMBuildSub(builder, res, |
| lp_build_const_int_vec(bld->gallivm, type, 127 - bias), ""); |
| |
| return res; |
| } |
| |
| |
| /** |
| * Extract the mantissa of the a floating. |
| * |
| * Result is a floating point value with |
| * |
| * x / floor(log2(x)) |
| */ |
| LLVMValueRef |
| lp_build_extract_mantissa(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| unsigned mantissa = lp_mantissa(type); |
| LLVMValueRef mantmask = lp_build_const_int_vec(bld->gallivm, type, |
| (1ULL << mantissa) - 1); |
| LLVMValueRef one = LLVMConstBitCast(bld->one, bld->int_vec_type); |
| LLVMValueRef res; |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| assert(type.floating); |
| |
| x = LLVMBuildBitCast(builder, x, bld->int_vec_type, ""); |
| |
| /* res = x / 2**ipart */ |
| res = LLVMBuildAnd(builder, x, mantmask, ""); |
| res = LLVMBuildOr(builder, res, one, ""); |
| res = LLVMBuildBitCast(builder, res, bld->vec_type, ""); |
| |
| return res; |
| } |
| |
| |
| |
| /** |
| * Minimax polynomial fit of log2((1.0 + sqrt(x))/(1.0 - sqrt(x)))/sqrt(x) ,for x in range of [0, 1/9[ |
| * These coefficients can be generate with |
| * http://www.boost.org/doc/libs/1_36_0/libs/math/doc/sf_and_dist/html/math_toolkit/toolkit/internals2/minimax.html |
| */ |
| const double lp_build_log2_polynomial[] = { |
| #if LOG_POLY_DEGREE == 5 |
| 2.88539008148777786488L, |
| 0.961796878841293367824L, |
| 0.577058946784739859012L, |
| 0.412914355135828735411L, |
| 0.308591899232910175289L, |
| 0.352376952300281371868L, |
| #elif LOG_POLY_DEGREE == 4 |
| 2.88539009343309178325L, |
| 0.961791550404184197881L, |
| 0.577440339438736392009L, |
| 0.403343858251329912514L, |
| 0.406718052498846252698L, |
| #elif LOG_POLY_DEGREE == 3 |
| 2.88538959748872753838L, |
| 0.961932915889597772928L, |
| 0.571118517972136195241L, |
| 0.493997535084709500285L, |
| #else |
| #error |
| #endif |
| }; |
| |
| /** |
| * See http://www.devmaster.net/forums/showthread.php?p=43580 |
| * http://en.wikipedia.org/wiki/Logarithm#Calculation |
| * http://www.nezumi.demon.co.uk/consult/logx.htm |
| */ |
| void |
| lp_build_log2_approx(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef *p_exp, |
| LLVMValueRef *p_floor_log2, |
| LLVMValueRef *p_log2) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| const struct lp_type type = bld->type; |
| LLVMTypeRef vec_type = lp_build_vec_type(bld->gallivm, type); |
| LLVMTypeRef int_vec_type = lp_build_int_vec_type(bld->gallivm, type); |
| |
| LLVMValueRef expmask = lp_build_const_int_vec(bld->gallivm, type, 0x7f800000); |
| LLVMValueRef mantmask = lp_build_const_int_vec(bld->gallivm, type, 0x007fffff); |
| LLVMValueRef one = LLVMConstBitCast(bld->one, int_vec_type); |
| |
| LLVMValueRef i = NULL; |
| LLVMValueRef y = NULL; |
| LLVMValueRef z = NULL; |
| LLVMValueRef exp = NULL; |
| LLVMValueRef mant = NULL; |
| LLVMValueRef logexp = NULL; |
| LLVMValueRef logmant = NULL; |
| LLVMValueRef res = NULL; |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| if(p_exp || p_floor_log2 || p_log2) { |
| /* TODO: optimize the constant case */ |
| if (gallivm_debug & GALLIVM_DEBUG_PERF && |
| LLVMIsConstant(x)) { |
| debug_printf("%s: inefficient/imprecise constant arithmetic\n", |
| __FUNCTION__); |
| } |
| |
| assert(type.floating && type.width == 32); |
| |
| /* |
| * We don't explicitly handle denormalized numbers. They will yield a |
| * result in the neighbourhood of -127, which appears to be adequate |
| * enough. |
| */ |
| |
| i = LLVMBuildBitCast(builder, x, int_vec_type, ""); |
| |
| /* exp = (float) exponent(x) */ |
| exp = LLVMBuildAnd(builder, i, expmask, ""); |
| } |
| |
| if(p_floor_log2 || p_log2) { |
| logexp = LLVMBuildLShr(builder, exp, lp_build_const_int_vec(bld->gallivm, type, 23), ""); |
| logexp = LLVMBuildSub(builder, logexp, lp_build_const_int_vec(bld->gallivm, type, 127), ""); |
| logexp = LLVMBuildSIToFP(builder, logexp, vec_type, ""); |
| } |
| |
| if(p_log2) { |
| /* mant = 1 + (float) mantissa(x) */ |
| mant = LLVMBuildAnd(builder, i, mantmask, ""); |
| mant = LLVMBuildOr(builder, mant, one, ""); |
| mant = LLVMBuildBitCast(builder, mant, vec_type, ""); |
| |
| /* y = (mant - 1) / (mant + 1) */ |
| y = lp_build_div(bld, |
| lp_build_sub(bld, mant, bld->one), |
| lp_build_add(bld, mant, bld->one) |
| ); |
| |
| /* z = y^2 */ |
| z = lp_build_mul(bld, y, y); |
| |
| /* compute P(z) */ |
| logmant = lp_build_polynomial(bld, z, lp_build_log2_polynomial, |
| Elements(lp_build_log2_polynomial)); |
| |
| /* logmant = y * P(z) */ |
| logmant = lp_build_mul(bld, y, logmant); |
| |
| res = lp_build_add(bld, logmant, logexp); |
| } |
| |
| if(p_exp) { |
| exp = LLVMBuildBitCast(builder, exp, vec_type, ""); |
| *p_exp = exp; |
| } |
| |
| if(p_floor_log2) |
| *p_floor_log2 = logexp; |
| |
| if(p_log2) |
| *p_log2 = res; |
| } |
| |
| |
| LLVMValueRef |
| lp_build_log2(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| LLVMValueRef res; |
| lp_build_log2_approx(bld, x, NULL, NULL, &res); |
| return res; |
| } |
| |
| |
| /** |
| * Faster (and less accurate) log2. |
| * |
| * log2(x) = floor(log2(x)) - 1 + x / 2**floor(log2(x)) |
| * |
| * Piece-wise linear approximation, with exact results when x is a |
| * power of two. |
| * |
| * See http://www.flipcode.com/archives/Fast_log_Function.shtml |
| */ |
| LLVMValueRef |
| lp_build_fast_log2(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef ipart; |
| LLVMValueRef fpart; |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| assert(bld->type.floating); |
| |
| /* ipart = floor(log2(x)) - 1 */ |
| ipart = lp_build_extract_exponent(bld, x, -1); |
| ipart = LLVMBuildSIToFP(builder, ipart, bld->vec_type, ""); |
| |
| /* fpart = x / 2**ipart */ |
| fpart = lp_build_extract_mantissa(bld, x); |
| |
| /* ipart + fpart */ |
| return LLVMBuildFAdd(builder, ipart, fpart, ""); |
| } |
| |
| |
| /** |
| * Fast implementation of iround(log2(x)). |
| * |
| * Not an approximation -- it should give accurate results all the time. |
| */ |
| LLVMValueRef |
| lp_build_ilog2(struct lp_build_context *bld, |
| LLVMValueRef x) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef sqrt2 = lp_build_const_vec(bld->gallivm, bld->type, M_SQRT2); |
| LLVMValueRef ipart; |
| |
| assert(bld->type.floating); |
| |
| assert(lp_check_value(bld->type, x)); |
| |
| /* x * 2^(0.5) i.e., add 0.5 to the log2(x) */ |
| x = LLVMBuildFMul(builder, x, sqrt2, ""); |
| |
| /* ipart = floor(log2(x) + 0.5) */ |
| ipart = lp_build_extract_exponent(bld, x, 0); |
| |
| return ipart; |
| } |
| |
| LLVMValueRef |
| lp_build_mod(struct lp_build_context *bld, |
| LLVMValueRef x, |
| LLVMValueRef y) |
| { |
| LLVMBuilderRef builder = bld->gallivm->builder; |
| LLVMValueRef res; |
| const struct lp_type type = bld->type; |
| |
| assert(lp_check_value(type, x)); |
| assert(lp_check_value(type, y)); |
| |
| if (type.floating) |
| res = LLVMBuildFRem(builder, x, y, ""); |
| else if (type.sign) |
| res = LLVMBuildSRem(builder, x, y, ""); |
| else |
| res = LLVMBuildURem(builder, x, y, ""); |
| return res; |
| } |