/************************************************************************** * * Copyright 2009 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 functions for type conversions. * * We want to use the fastest type for a given computation whenever feasible. * The other side of this is that we need to be able convert between several * types accurately and efficiently. * * Conversion between types of different bit width is quite complex since a * * To remember there are a few invariants in type conversions: * * - register width must remain constant: * * src_type.width * src_type.length == dst_type.width * dst_type.length * * - total number of elements must remain constant: * * src_type.length * num_srcs == dst_type.length * num_dsts * * It is not always possible to do the conversion both accurately and * efficiently, usually due to lack of adequate machine instructions. In these * cases it is important not to cut shortcuts here and sacrifice accuracy, as * there this functions can be used anywhere. In the future we might have a * precision parameter which can gauge the accuracy vs efficiency compromise, * but for now if the data conversion between two stages happens to be the * bottleneck, then most likely should just avoid converting at all and run * both stages with the same type. * * Make sure to run lp_test_conv unit test after any change to this file. * * @author Jose Fonseca */ #include "util/u_debug.h" #include "util/u_math.h" #include "util/u_half.h" #include "util/u_cpu_detect.h" #include "lp_bld_type.h" #include "lp_bld_const.h" #include "lp_bld_arit.h" #include "lp_bld_bitarit.h" #include "lp_bld_pack.h" #include "lp_bld_conv.h" #include "lp_bld_logic.h" #include "lp_bld_intr.h" #include "lp_bld_printf.h" #include "lp_bld_format.h" /** * Converts int16 half-float to float32 * Note this can be performed in 1 instruction if vcvtph2ps exists (f16c/cvt16) * [llvm.x86.vcvtph2ps / _mm_cvtph_ps] * * @param src value to convert * */ LLVMValueRef lp_build_half_to_float(struct gallivm_state *gallivm, LLVMValueRef src) { LLVMBuilderRef builder = gallivm->builder; LLVMTypeRef src_type = LLVMTypeOf(src); unsigned src_length = LLVMGetTypeKind(src_type) == LLVMVectorTypeKind ? LLVMGetVectorSize(src_type) : 1; struct lp_type f32_type = lp_type_float_vec(32, 32 * src_length); struct lp_type i32_type = lp_type_int_vec(32, 32 * src_length); LLVMTypeRef int_vec_type = lp_build_vec_type(gallivm, i32_type); LLVMValueRef h; if (util_cpu_caps.has_f16c && HAVE_LLVM >= 0x0301 && (src_length == 4 || src_length == 8)) { const char *intrinsic = NULL; if (src_length == 4) { src = lp_build_pad_vector(gallivm, src, 8); intrinsic = "llvm.x86.vcvtph2ps.128"; } else { intrinsic = "llvm.x86.vcvtph2ps.256"; } return lp_build_intrinsic_unary(builder, intrinsic, lp_build_vec_type(gallivm, f32_type), src); } /* Convert int16 vector to int32 vector by zero ext (might generate bad code) */ h = LLVMBuildZExt(builder, src, int_vec_type, ""); return lp_build_smallfloat_to_float(gallivm, f32_type, h, 10, 5, 0, true); } /** * Converts float32 to int16 half-float * Note this can be performed in 1 instruction if vcvtps2ph exists (f16c/cvt16) * [llvm.x86.vcvtps2ph / _mm_cvtps_ph] * * @param src value to convert * * Convert float32 to half floats, preserving Infs and NaNs, * with rounding towards zero (trunc). */ LLVMValueRef lp_build_float_to_half(struct gallivm_state *gallivm, LLVMValueRef src) { LLVMBuilderRef builder = gallivm->builder; LLVMTypeRef f32_vec_type = LLVMTypeOf(src); unsigned length = LLVMGetTypeKind(f32_vec_type) == LLVMVectorTypeKind ? LLVMGetVectorSize(f32_vec_type) : 1; struct lp_type i32_type = lp_type_int_vec(32, 32 * length); struct lp_type i16_type = lp_type_int_vec(16, 16 * length); LLVMValueRef result; if (util_cpu_caps.has_f16c && HAVE_LLVM >= 0x0301 && (length == 4 || length == 8)) { struct lp_type i168_type = lp_type_int_vec(16, 16 * 8); unsigned mode = 3; /* same as LP_BUILD_ROUND_TRUNCATE */ LLVMTypeRef i32t = LLVMInt32TypeInContext(gallivm->context); const char *intrinsic = NULL; if (length == 4) { intrinsic = "llvm.x86.vcvtps2ph.128"; } else { intrinsic = "llvm.x86.vcvtps2ph.256"; } result = lp_build_intrinsic_binary(builder, intrinsic, lp_build_vec_type(gallivm, i168_type), src, LLVMConstInt(i32t, mode, 0)); if (length == 4) { result = lp_build_extract_range(gallivm, result, 0, 4); } } else { result = lp_build_float_to_smallfloat(gallivm, i32_type, src, 10, 5, 0, true); /* Convert int32 vector to int16 vector by trunc (might generate bad code) */ result = LLVMBuildTrunc(builder, result, lp_build_vec_type(gallivm, i16_type), ""); } /* * Debugging code. */ if (0) { LLVMTypeRef i32t = LLVMInt32TypeInContext(gallivm->context); LLVMTypeRef i16t = LLVMInt16TypeInContext(gallivm->context); LLVMTypeRef f32t = LLVMFloatTypeInContext(gallivm->context); LLVMValueRef ref_result = LLVMGetUndef(LLVMVectorType(i16t, length)); unsigned i; LLVMTypeRef func_type = LLVMFunctionType(i16t, &f32t, 1, 0); LLVMValueRef func = lp_build_const_int_pointer(gallivm, func_to_pointer((func_pointer)util_float_to_half)); func = LLVMBuildBitCast(builder, func, LLVMPointerType(func_type, 0), "util_float_to_half"); for (i = 0; i < length; ++i) { LLVMValueRef index = LLVMConstInt(i32t, i, 0); LLVMValueRef f32 = LLVMBuildExtractElement(builder, src, index, ""); #if 0 /* XXX: not really supported by backends */ LLVMValueRef f16 = lp_build_intrinsic_unary(builder, "llvm.convert.to.fp16", i16t, f32); #else LLVMValueRef f16 = LLVMBuildCall(builder, func, &f32, 1, ""); #endif ref_result = LLVMBuildInsertElement(builder, ref_result, f16, index, ""); } lp_build_print_value(gallivm, "src = ", src); lp_build_print_value(gallivm, "llvm = ", result); lp_build_print_value(gallivm, "util = ", ref_result); lp_build_printf(gallivm, "\n"); } return result; } /** * Special case for converting clamped IEEE-754 floats to unsigned norms. * * The mathematical voodoo below may seem excessive but it is actually * paramount we do it this way for several reasons. First, there is no single * precision FP to unsigned integer conversion Intel SSE instruction. Second, * secondly, even if there was, since the FP's mantissa takes only a fraction * of register bits the typically scale and cast approach would require double * precision for accurate results, and therefore half the throughput * * Although the result values can be scaled to an arbitrary bit width specified * by dst_width, the actual result type will have the same width. * * Ex: src = { float, float, float, float } * return { i32, i32, i32, i32 } where each value is in [0, 2^dst_width-1]. */ LLVMValueRef lp_build_clamped_float_to_unsigned_norm(struct gallivm_state *gallivm, struct lp_type src_type, unsigned dst_width, LLVMValueRef src) { LLVMBuilderRef builder = gallivm->builder; LLVMTypeRef int_vec_type = lp_build_int_vec_type(gallivm, src_type); LLVMValueRef res; unsigned mantissa; assert(src_type.floating); assert(dst_width <= src_type.width); src_type.sign = FALSE; mantissa = lp_mantissa(src_type); if (dst_width <= mantissa) { /* * Apply magic coefficients that will make the desired result to appear * in the lowest significant bits of the mantissa, with correct rounding. * * This only works if the destination width fits in the mantissa. */ unsigned long long ubound; unsigned long long mask; double scale; double bias; ubound = (1ULL << dst_width); mask = ubound - 1; scale = (double)mask/ubound; bias = (double)(1ULL << (mantissa - dst_width)); res = LLVMBuildFMul(builder, src, lp_build_const_vec(gallivm, src_type, scale), ""); /* instead of fadd/and could (with sse2) just use lp_build_iround */ res = LLVMBuildFAdd(builder, res, lp_build_const_vec(gallivm, src_type, bias), ""); res = LLVMBuildBitCast(builder, res, int_vec_type, ""); res = LLVMBuildAnd(builder, res, lp_build_const_int_vec(gallivm, src_type, mask), ""); } else if (dst_width == (mantissa + 1)) { /* * The destination width matches exactly what can be represented in * floating point (i.e., mantissa + 1 bits). So do a straight * multiplication followed by casting. No further rounding is necessary. */ double scale; scale = (double)((1ULL << dst_width) - 1); res = LLVMBuildFMul(builder, src, lp_build_const_vec(gallivm, src_type, scale), ""); res = LLVMBuildFPToSI(builder, res, int_vec_type, ""); } else { /* * The destination exceeds what can be represented in the floating point. * So multiply by the largest power two we get away with, and when * subtract the most significant bit to rescale to normalized values. * * The largest power of two factor we can get away is * (1 << (src_type.width - 1)), because we need to use signed . In theory it * should be (1 << (src_type.width - 2)), but IEEE 754 rules states * INT_MIN should be returned in FPToSI, which is the correct result for * values near 1.0! * * This means we get (src_type.width - 1) correct bits for values near 0.0, * and (mantissa + 1) correct bits for values near 1.0. Equally or more * important, we also get exact results for 0.0 and 1.0. */ unsigned n = MIN2(src_type.width - 1, dst_width); double scale = (double)(1ULL << n); unsigned lshift = dst_width - n; unsigned rshift = n; LLVMValueRef lshifted; LLVMValueRef rshifted; res = LLVMBuildFMul(builder, src, lp_build_const_vec(gallivm, src_type, scale), ""); res = LLVMBuildFPToSI(builder, res, int_vec_type, ""); /* * Align the most significant bit to its final place. * * This will cause 1.0 to overflow to 0, but the later adjustment will * get it right. */ if (lshift) { lshifted = LLVMBuildShl(builder, res, lp_build_const_int_vec(gallivm, src_type, lshift), ""); } else { lshifted = res; } /* * Align the most significant bit to the right. */ rshifted = LLVMBuildLShr(builder, res, lp_build_const_int_vec(gallivm, src_type, rshift), ""); /* * Subtract the MSB to the LSB, therefore re-scaling from * (1 << dst_width) to ((1 << dst_width) - 1). */ res = LLVMBuildSub(builder, lshifted, rshifted, ""); } return res; } /** * Inverse of lp_build_clamped_float_to_unsigned_norm above. * Ex: src = { i32, i32, i32, i32 } with values in range [0, 2^src_width-1] * return {float, float, float, float} with values in range [0, 1]. */ LLVMValueRef lp_build_unsigned_norm_to_float(struct gallivm_state *gallivm, unsigned src_width, struct lp_type dst_type, LLVMValueRef src) { LLVMBuilderRef builder = gallivm->builder; LLVMTypeRef vec_type = lp_build_vec_type(gallivm, dst_type); LLVMTypeRef int_vec_type = lp_build_int_vec_type(gallivm, dst_type); LLVMValueRef bias_; LLVMValueRef res; unsigned mantissa; unsigned n; unsigned long long ubound; unsigned long long mask; double scale; double bias; assert(dst_type.floating); mantissa = lp_mantissa(dst_type); if (src_width <= (mantissa + 1)) { /* * The source width matches fits what can be represented in floating * point (i.e., mantissa + 1 bits). So do a straight multiplication * followed by casting. No further rounding is necessary. */ scale = 1.0/(double)((1ULL << src_width) - 1); res = LLVMBuildSIToFP(builder, src, vec_type, ""); res = LLVMBuildFMul(builder, res, lp_build_const_vec(gallivm, dst_type, scale), ""); return res; } else { /* * The source width exceeds what can be represented in floating * point. So truncate the incoming values. */ n = MIN2(mantissa, src_width); ubound = ((unsigned long long)1 << n); mask = ubound - 1; scale = (double)ubound/mask; bias = (double)((unsigned long long)1 << (mantissa - n)); res = src; if (src_width > mantissa) { int shift = src_width - mantissa; res = LLVMBuildLShr(builder, res, lp_build_const_int_vec(gallivm, dst_type, shift), ""); } bias_ = lp_build_const_vec(gallivm, dst_type, bias); res = LLVMBuildOr(builder, res, LLVMBuildBitCast(builder, bias_, int_vec_type, ""), ""); res = LLVMBuildBitCast(builder, res, vec_type, ""); res = LLVMBuildFSub(builder, res, bias_, ""); res = LLVMBuildFMul(builder, res, lp_build_const_vec(gallivm, dst_type, scale), ""); } return res; } /** * Pick a suitable num_dsts for lp_build_conv to ensure optimal cases are used. * * Returns the number of dsts created from src */ int lp_build_conv_auto(struct gallivm_state *gallivm, struct lp_type src_type, struct lp_type* dst_type, const LLVMValueRef *src, unsigned num_srcs, LLVMValueRef *dst) { int i; int num_dsts = num_srcs; if (src_type.floating == dst_type->floating && src_type.width == dst_type->width && src_type.length == dst_type->length && src_type.fixed == dst_type->fixed && src_type.norm == dst_type->norm && src_type.sign == dst_type->sign) return num_dsts; /* Special case 4x4f -> 1x16ub or 2x8f -> 1x16ub */ if (src_type.floating == 1 && src_type.fixed == 0 && src_type.sign == 1 && src_type.norm == 0 && src_type.width == 32 && dst_type->floating == 0 && dst_type->fixed == 0 && dst_type->sign == 0 && dst_type->norm == 1 && dst_type->width == 8) { /* Special case 4x4f --> 1x16ub */ if (src_type.length == 4 && util_cpu_caps.has_sse2) { num_dsts = (num_srcs + 3) / 4; dst_type->length = num_srcs * 4 >= 16 ? 16 : num_srcs * 4; lp_build_conv(gallivm, src_type, *dst_type, src, num_srcs, dst, num_dsts); return num_dsts; } /* Special case 2x8f --> 1x16ub */ if (src_type.length == 8 && util_cpu_caps.has_avx) { num_dsts = (num_srcs + 1) / 2; dst_type->length = num_srcs * 8 >= 16 ? 16 : num_srcs * 8; lp_build_conv(gallivm, src_type, *dst_type, src, num_srcs, dst, num_dsts); return num_dsts; } } /* lp_build_resize does not support M:N */ if (src_type.width == dst_type->width) { lp_build_conv(gallivm, src_type, *dst_type, src, num_srcs, dst, num_dsts); } else { for (i = 0; i < num_srcs; ++i) { lp_build_conv(gallivm, src_type, *dst_type, &src[i], 1, &dst[i], 1); } } return num_dsts; } /** * Generic type conversion. * * TODO: Take a precision argument, or even better, add a new precision member * to the lp_type union. */ void lp_build_conv(struct gallivm_state *gallivm, struct lp_type src_type, struct lp_type dst_type, const LLVMValueRef *src, unsigned num_srcs, LLVMValueRef *dst, unsigned num_dsts) { LLVMBuilderRef builder = gallivm->builder; struct lp_type tmp_type; LLVMValueRef tmp[LP_MAX_VECTOR_LENGTH]; unsigned num_tmps; unsigned i; /* We must not loose or gain channels. Only precision */ assert(src_type.length * num_srcs == dst_type.length * num_dsts); assert(src_type.length <= LP_MAX_VECTOR_LENGTH); assert(dst_type.length <= LP_MAX_VECTOR_LENGTH); assert(num_srcs <= LP_MAX_VECTOR_LENGTH); assert(num_dsts <= LP_MAX_VECTOR_LENGTH); tmp_type = src_type; for(i = 0; i < num_srcs; ++i) { assert(lp_check_value(src_type, src[i])); tmp[i] = src[i]; } num_tmps = num_srcs; /* Special case 4x4f --> 1x16ub, 2x4f -> 1x8ub, 1x4f -> 1x4ub */ if (src_type.floating == 1 && src_type.fixed == 0 && src_type.sign == 1 && src_type.norm == 0 && src_type.width == 32 && src_type.length == 4 && dst_type.floating == 0 && dst_type.fixed == 0 && dst_type.sign == 0 && dst_type.norm == 1 && dst_type.width == 8 && ((dst_type.length == 16 && 4 * num_dsts == num_srcs) || (num_dsts == 1 && dst_type.length * num_srcs == 16 && num_srcs != 3)) && util_cpu_caps.has_sse2) { struct lp_build_context bld; struct lp_type int16_type, int32_type; struct lp_type dst_type_ext = dst_type; LLVMValueRef const_255f; unsigned i, j; lp_build_context_init(&bld, gallivm, src_type); dst_type_ext.length = 16; int16_type = int32_type = dst_type_ext; int16_type.width *= 2; int16_type.length /= 2; int16_type.sign = 1; int32_type.width *= 4; int32_type.length /= 4; int32_type.sign = 1; const_255f = lp_build_const_vec(gallivm, src_type, 255.0f); for (i = 0; i < num_dsts; ++i, src += 4) { LLVMValueRef lo, hi; for (j = 0; j < dst_type.length / 4; ++j) { tmp[j] = LLVMBuildFMul(builder, src[j], const_255f, ""); tmp[j] = lp_build_iround(&bld, tmp[j]); } if (num_srcs == 1) { tmp[1] = tmp[0]; } /* relying on clamping behavior of sse2 intrinsics here */ lo = lp_build_pack2(gallivm, int32_type, int16_type, tmp[0], tmp[1]); if (num_srcs < 4) { hi = lo; } else { hi = lp_build_pack2(gallivm, int32_type, int16_type, tmp[2], tmp[3]); } dst[i] = lp_build_pack2(gallivm, int16_type, dst_type_ext, lo, hi); } if (num_srcs < 4) { dst[0] = lp_build_extract_range(gallivm, dst[0], 0, dst_type.length); } return; } /* Special case 2x8f --> 1x16ub, 1x8f ->1x8ub */ else if (src_type.floating == 1 && src_type.fixed == 0 && src_type.sign == 1 && src_type.norm == 0 && src_type.width == 32 && src_type.length == 8 && dst_type.floating == 0 && dst_type.fixed == 0 && dst_type.sign == 0 && dst_type.norm == 1 && dst_type.width == 8 && ((dst_type.length == 16 && 2 * num_dsts == num_srcs) || (num_dsts == 1 && dst_type.length * num_srcs == 8)) && util_cpu_caps.has_avx) { struct lp_build_context bld; struct lp_type int16_type, int32_type; struct lp_type dst_type_ext = dst_type; LLVMValueRef const_255f; unsigned i; lp_build_context_init(&bld, gallivm, src_type); dst_type_ext.length = 16; int16_type = int32_type = dst_type_ext; int16_type.width *= 2; int16_type.length /= 2; int16_type.sign = 1; int32_type.width *= 4; int32_type.length /= 4; int32_type.sign = 1; const_255f = lp_build_const_vec(gallivm, src_type, 255.0f); for (i = 0; i < num_dsts; ++i, src += 2) { LLVMValueRef lo, hi, a, b; a = LLVMBuildFMul(builder, src[0], const_255f, ""); a = lp_build_iround(&bld, a); tmp[0] = lp_build_extract_range(gallivm, a, 0, 4); tmp[1] = lp_build_extract_range(gallivm, a, 4, 4); /* relying on clamping behavior of sse2 intrinsics here */ lo = lp_build_pack2(gallivm, int32_type, int16_type, tmp[0], tmp[1]); if (num_srcs == 1) { hi = lo; } else { b = LLVMBuildFMul(builder, src[1], const_255f, ""); b = lp_build_iround(&bld, b); tmp[2] = lp_build_extract_range(gallivm, b, 0, 4); tmp[3] = lp_build_extract_range(gallivm, b, 4, 4); hi = lp_build_pack2(gallivm, int32_type, int16_type, tmp[2], tmp[3]); } dst[i] = lp_build_pack2(gallivm, int16_type, dst_type_ext, lo, hi); } if (num_srcs == 1) { dst[0] = lp_build_extract_range(gallivm, dst[0], 0, dst_type.length); } return; } /* Special case -> 16bit half-float */ else if (dst_type.floating && dst_type.width == 16) { /* Only support src as 32bit float currently */ assert(src_type.floating && src_type.width == 32); for(i = 0; i < num_tmps; ++i) dst[i] = lp_build_float_to_half(gallivm, tmp[i]); return; } /* Pre convert half-floats to floats */ else if (src_type.floating && src_type.width == 16) { for(i = 0; i < num_tmps; ++i) tmp[i] = lp_build_half_to_float(gallivm, tmp[i]); tmp_type.width = 32; } /* * Clamp if necessary */ if(memcmp(&src_type, &dst_type, sizeof src_type) != 0) { struct lp_build_context bld; double src_min = lp_const_min(src_type); double dst_min = lp_const_min(dst_type); double src_max = lp_const_max(src_type); double dst_max = lp_const_max(dst_type); LLVMValueRef thres; lp_build_context_init(&bld, gallivm, tmp_type); if(src_min < dst_min) { if(dst_min == 0.0) thres = bld.zero; else thres = lp_build_const_vec(gallivm, src_type, dst_min); for(i = 0; i < num_tmps; ++i) tmp[i] = lp_build_max(&bld, tmp[i], thres); } if(src_max > dst_max) { if(dst_max == 1.0) thres = bld.one; else thres = lp_build_const_vec(gallivm, src_type, dst_max); for(i = 0; i < num_tmps; ++i) tmp[i] = lp_build_min(&bld, tmp[i], thres); } } /* * Scale to the narrowest range */ if(dst_type.floating) { /* Nothing to do */ } else if(tmp_type.floating) { if(!dst_type.fixed && !dst_type.sign && dst_type.norm) { for(i = 0; i < num_tmps; ++i) { tmp[i] = lp_build_clamped_float_to_unsigned_norm(gallivm, tmp_type, dst_type.width, tmp[i]); } tmp_type.floating = FALSE; } else { double dst_scale = lp_const_scale(dst_type); if (dst_scale != 1.0) { LLVMValueRef scale = lp_build_const_vec(gallivm, tmp_type, dst_scale); for(i = 0; i < num_tmps; ++i) tmp[i] = LLVMBuildFMul(builder, tmp[i], scale, ""); } /* * these functions will use fptosi in some form which won't work * with 32bit uint dst. Causes lp_test_conv failures though. */ if (0) assert(dst_type.sign || dst_type.width < 32); if (dst_type.sign && dst_type.norm && !dst_type.fixed) { struct lp_build_context bld; lp_build_context_init(&bld, gallivm, tmp_type); for(i = 0; i < num_tmps; ++i) { tmp[i] = lp_build_iround(&bld, tmp[i]); } tmp_type.floating = FALSE; } else { LLVMTypeRef tmp_vec_type; tmp_type.floating = FALSE; tmp_vec_type = lp_build_vec_type(gallivm, tmp_type); for(i = 0; i < num_tmps; ++i) { #if 0 if(dst_type.sign) tmp[i] = LLVMBuildFPToSI(builder, tmp[i], tmp_vec_type, ""); else tmp[i] = LLVMBuildFPToUI(builder, tmp[i], tmp_vec_type, ""); #else /* FIXME: there is no SSE counterpart for LLVMBuildFPToUI */ tmp[i] = LLVMBuildFPToSI(builder, tmp[i], tmp_vec_type, ""); #endif } } } } else { unsigned src_shift = lp_const_shift(src_type); unsigned dst_shift = lp_const_shift(dst_type); unsigned src_offset = lp_const_offset(src_type); unsigned dst_offset = lp_const_offset(dst_type); /* Compensate for different offsets */ if (dst_offset > src_offset && src_type.width > dst_type.width) { for (i = 0; i < num_tmps; ++i) { LLVMValueRef shifted; LLVMValueRef shift = lp_build_const_int_vec(gallivm, tmp_type, src_shift - 1); if(src_type.sign) shifted = LLVMBuildAShr(builder, tmp[i], shift, ""); else shifted = LLVMBuildLShr(builder, tmp[i], shift, ""); tmp[i] = LLVMBuildSub(builder, tmp[i], shifted, ""); } } if(src_shift > dst_shift) { LLVMValueRef shift = lp_build_const_int_vec(gallivm, tmp_type, src_shift - dst_shift); for(i = 0; i < num_tmps; ++i) if(src_type.sign) tmp[i] = LLVMBuildAShr(builder, tmp[i], shift, ""); else tmp[i] = LLVMBuildLShr(builder, tmp[i], shift, ""); } } /* * Truncate or expand bit width * * No data conversion should happen here, although the sign bits are * crucial to avoid bad clamping. */ { struct lp_type new_type; new_type = tmp_type; new_type.sign = dst_type.sign; new_type.width = dst_type.width; new_type.length = dst_type.length; lp_build_resize(gallivm, tmp_type, new_type, tmp, num_srcs, tmp, num_dsts); tmp_type = new_type; num_tmps = num_dsts; } /* * Scale to the widest range */ if(src_type.floating) { /* Nothing to do */ } else if(!src_type.floating && dst_type.floating) { if(!src_type.fixed && !src_type.sign && src_type.norm) { for(i = 0; i < num_tmps; ++i) { tmp[i] = lp_build_unsigned_norm_to_float(gallivm, src_type.width, dst_type, tmp[i]); } tmp_type.floating = TRUE; } else { double src_scale = lp_const_scale(src_type); LLVMTypeRef tmp_vec_type; /* Use an equally sized integer for intermediate computations */ tmp_type.floating = TRUE; tmp_type.sign = TRUE; tmp_vec_type = lp_build_vec_type(gallivm, tmp_type); for(i = 0; i < num_tmps; ++i) { #if 0 if(dst_type.sign) tmp[i] = LLVMBuildSIToFP(builder, tmp[i], tmp_vec_type, ""); else tmp[i] = LLVMBuildUIToFP(builder, tmp[i], tmp_vec_type, ""); #else /* FIXME: there is no SSE counterpart for LLVMBuildUIToFP */ tmp[i] = LLVMBuildSIToFP(builder, tmp[i], tmp_vec_type, ""); #endif } if (src_scale != 1.0) { LLVMValueRef scale = lp_build_const_vec(gallivm, tmp_type, 1.0/src_scale); for(i = 0; i < num_tmps; ++i) tmp[i] = LLVMBuildFMul(builder, tmp[i], scale, ""); } /* the formula above will produce value below -1.0 for most negative * value but everything seems happy with that hence disable for now */ if (0 && !src_type.fixed && src_type.norm && src_type.sign) { struct lp_build_context bld; lp_build_context_init(&bld, gallivm, dst_type); for(i = 0; i < num_tmps; ++i) { tmp[i] = lp_build_max(&bld, tmp[i], lp_build_const_vec(gallivm, dst_type, -1.0f)); } } } } else { unsigned src_shift = lp_const_shift(src_type); unsigned dst_shift = lp_const_shift(dst_type); unsigned src_offset = lp_const_offset(src_type); unsigned dst_offset = lp_const_offset(dst_type); if (src_shift < dst_shift) { LLVMValueRef pre_shift[LP_MAX_VECTOR_LENGTH]; LLVMValueRef shift = lp_build_const_int_vec(gallivm, tmp_type, dst_shift - src_shift); for (i = 0; i < num_tmps; ++i) { pre_shift[i] = tmp[i]; tmp[i] = LLVMBuildShl(builder, tmp[i], shift, ""); } /* Compensate for different offsets */ if (dst_offset > src_offset) { for (i = 0; i < num_tmps; ++i) { tmp[i] = LLVMBuildSub(builder, tmp[i], pre_shift[i], ""); } } } } for(i = 0; i < num_dsts; ++i) { dst[i] = tmp[i]; assert(lp_check_value(dst_type, dst[i])); } } /** * Bit mask conversion. * * This will convert the integer masks that match the given types. * * The mask values should 0 or -1, i.e., all bits either set to zero or one. * Any other value will likely cause unpredictable results. * * This is basically a very trimmed down version of lp_build_conv. */ void lp_build_conv_mask(struct gallivm_state *gallivm, struct lp_type src_type, struct lp_type dst_type, const LLVMValueRef *src, unsigned num_srcs, LLVMValueRef *dst, unsigned num_dsts) { /* We must not loose or gain channels. Only precision */ assert(src_type.length * num_srcs == dst_type.length * num_dsts); /* * Drop * * We assume all values are 0 or -1 */ src_type.floating = FALSE; src_type.fixed = FALSE; src_type.sign = TRUE; src_type.norm = FALSE; dst_type.floating = FALSE; dst_type.fixed = FALSE; dst_type.sign = TRUE; dst_type.norm = FALSE; /* * Truncate or expand bit width */ lp_build_resize(gallivm, src_type, dst_type, src, num_srcs, dst, num_dsts); }