From 1709ace359a2d513cf09de28bf372248f6103f6a Mon Sep 17 00:00:00 2001 From: José Fonseca Date: Wed, 12 Aug 2009 02:34:55 +0100 Subject: llvmpipe: Implement more arithmetic functions. --- src/gallium/drivers/llvmpipe/lp_bld_arit.c | 175 ++++++++++++++++++++--------- src/gallium/drivers/llvmpipe/lp_bld_arit.h | 16 +++ 2 files changed, 140 insertions(+), 51 deletions(-) (limited to 'src') diff --git a/src/gallium/drivers/llvmpipe/lp_bld_arit.c b/src/gallium/drivers/llvmpipe/lp_bld_arit.c index a73331ddc9..a322ec233e 100644 --- a/src/gallium/drivers/llvmpipe/lp_bld_arit.c +++ b/src/gallium/drivers/llvmpipe/lp_bld_arit.c @@ -46,8 +46,10 @@ #include "util/u_debug.h" +#include "util/u_string.h" #include "lp_bld_type.h" +#include "lp_bld_const.h" #include "lp_bld_intr.h" #include "lp_bld_arit.h" @@ -555,23 +557,13 @@ lp_build_sqrt(struct lp_build_context *bld, { const union lp_type type = bld->type; LLVMTypeRef vec_type = lp_build_vec_type(type); - const char *intrinsic; + char intrinsic[32]; + /* TODO: optimize the constant case */ /* TODO: optimize the constant case */ assert(type.floating); - - switch(type.width) { - case 32: - intrinsic = "llvm.sqrt.f32"; - break; - case 64: - intrinsic = "llvm.sqrt.f64"; - break; - default: - assert(0); - return LLVMGetUndef(vec_type); - } + util_snprintf(intrinsic, sizeof intrinsic, "llvm.sqrt.v%uf%u", type.length, type.width); return lp_build_intrinsic_unary(bld->builder, intrinsic, vec_type, a); } @@ -629,23 +621,12 @@ lp_build_cos(struct lp_build_context *bld, { const union lp_type type = bld->type; LLVMTypeRef vec_type = lp_build_vec_type(type); - const char *intrinsic; + char intrinsic[32]; /* TODO: optimize the constant case */ assert(type.floating); - - switch(type.width) { - case 32: - intrinsic = "llvm.cos.f32"; - break; - case 64: - intrinsic = "llvm.cos.f64"; - break; - default: - assert(0); - return LLVMGetUndef(vec_type); - } + util_snprintf(intrinsic, sizeof intrinsic, "llvm.cos.v%uf%u", type.length, type.width); return lp_build_intrinsic_unary(bld->builder, intrinsic, vec_type, a); } @@ -657,23 +638,12 @@ lp_build_sin(struct lp_build_context *bld, { const union lp_type type = bld->type; LLVMTypeRef vec_type = lp_build_vec_type(type); - const char *intrinsic; + char intrinsic[32]; /* TODO: optimize the constant case */ assert(type.floating); - - switch(type.width) { - case 32: - intrinsic = "llvm.sin.f32"; - break; - case 64: - intrinsic = "llvm.sin.f64"; - break; - default: - assert(0); - return LLVMGetUndef(vec_type); - } + util_snprintf(intrinsic, sizeof intrinsic, "llvm.sin.v%uf%u", type.length, type.width); return lp_build_intrinsic_unary(bld->builder, intrinsic, vec_type, a); } @@ -686,24 +656,127 @@ lp_build_pow(struct lp_build_context *bld, { const union lp_type type = bld->type; LLVMTypeRef vec_type = lp_build_vec_type(type); - const char *intrinsic; + char intrinsic[32]; /* TODO: optimize the constant case */ assert(type.floating); + util_snprintf(intrinsic, sizeof intrinsic, "llvm.pow.v%uf%u", type.length, type.width); - switch(type.width) { - case 32: - intrinsic = "llvm.pow.f32"; - break; - case 64: - intrinsic = "llvm.pow.f64"; - break; - default: - assert(0); - return LLVMGetUndef(vec_type); + return lp_build_intrinsic_binary(bld->builder, intrinsic, vec_type, a, b); +} + + +LLVMValueRef +lp_build_exp(struct lp_build_context *bld, + LLVMValueRef a) +{ + /* FIXME: optimize */ + return lp_build_pow(bld, lp_build_const_uni(bld->type, 2.7182818284590452354), a); +} + + +LLVMValueRef +lp_build_log(struct lp_build_context *bld, + LLVMValueRef a) +{ + /* FIXME: implement */ + return bld->undef; +} + + +#define EXP_POLY_DEGREE 3 +#define LOG_POLY_DEGREE 5 + + +static LLVMValueRef +lp_build_polynomial(struct lp_build_context *bld, + LLVMValueRef x, + const double *coeffs, + unsigned num_coeffs) +{ + const union lp_type type = bld->type; + LLVMValueRef res = NULL; + unsigned i; + + for (i = num_coeffs; i--; ) { + LLVMValueRef coeff = lp_build_const_uni(type, coeffs[i]); + if(res) + res = lp_build_add(bld, coeff, lp_build_mul(bld, x, res)); + else + res = coeff; } - return lp_build_intrinsic_binary(bld->builder, intrinsic, vec_type, a, b); + if(res) + return res; + else + return bld->undef; +} + + +LLVMValueRef +lp_build_exp2(struct lp_build_context *bld, + LLVMValueRef a) +{ + /* FIXME: optimize */ + return lp_build_pow(bld, lp_build_const_uni(bld->type, 2.0), a); } + +/** + * See http://www.devmaster.net/forums/showthread.php?p=43580 + */ +LLVMValueRef +lp_build_log2(struct lp_build_context *bld, + LLVMValueRef x) +{ + const union lp_type type = bld->type; + LLVMTypeRef vec_type = lp_build_vec_type(type); + LLVMTypeRef int_vec_type = lp_build_int_vec_type(type); + + LLVMValueRef expmask = lp_build_int_const_uni(type, 0x7f800000); + LLVMValueRef mantmask = lp_build_int_const_uni(type, 0x007fffff); + LLVMValueRef one = LLVMConstBitCast(bld->one, int_vec_type); + + LLVMValueRef i = LLVMBuildBitCast(bld->builder, x, int_vec_type, ""); + + LLVMValueRef exp; + LLVMValueRef mant; + LLVMValueRef logmant; + + /* exp = (float) exponent(x) */ + exp = LLVMBuildAnd(bld->builder, i, expmask, ""); + exp = LLVMBuildLShr(bld->builder, exp, lp_build_int_const_uni(type, 23), ""); + exp = LLVMBuildSub(bld->builder, exp, lp_build_int_const_uni(type, 127), ""); + exp = LLVMBuildSIToFP(bld->builder, exp, vec_type, ""); + + /* mant = (float) mantissa(x) */ + mant = LLVMBuildAnd(bld->builder, i, mantmask, ""); + mant = LLVMBuildOr(bld->builder, mant, one, ""); + mant = LLVMBuildSIToFP(bld->builder, mant, vec_type, ""); + + /* Minimax polynomial fit of log2(x)/(x - 1), for x in range [1, 2[ + * 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 polynomial[] = { +#if LOG_POLY_DEGREE == 6 + 3.11578814719469302614, -3.32419399085241980044, 2.59883907202499966007, -1.23152682416275988241, 0.318212422185251071475, -0.0344359067839062357313 +#elif LOG_POLY_DEGREE == 5 + 2.8882704548164776201, -2.52074962577807006663, 1.48116647521213171641, -0.465725644288844778798, 0.0596515482674574969533 +#elif LOG_POLY_DEGREE == 4 + 2.61761038894603480148, -1.75647175389045657003, 0.688243882994381274313, -0.107254423828329604454 +#elif LOG_POLY_DEGREE == 3 + 2.28330284476918490682, -1.04913055217340124191, 0.204446009836232697516 +#else +#error +#endif + }; + + logmant = lp_build_polynomial(bld, mant, polynomial, sizeof(polynomial)/sizeof(polynomial[0])); + + /* This effectively increases the polynomial degree by one, but ensures that log2(1) == 0*/ + logmant = LLVMBuildMul(bld->builder, logmant, LLVMBuildMul(bld->builder, mant, bld->one, ""), ""); + + return LLVMBuildAdd(bld->builder, logmant, exp, ""); +} diff --git a/src/gallium/drivers/llvmpipe/lp_bld_arit.h b/src/gallium/drivers/llvmpipe/lp_bld_arit.h index 2545d2cdfb..9f8fccb0d4 100644 --- a/src/gallium/drivers/llvmpipe/lp_bld_arit.h +++ b/src/gallium/drivers/llvmpipe/lp_bld_arit.h @@ -110,4 +110,20 @@ lp_build_pow(struct lp_build_context *bld, LLVMValueRef a, LLVMValueRef b); +LLVMValueRef +lp_build_exp(struct lp_build_context *bld, + LLVMValueRef a); + +LLVMValueRef +lp_build_log(struct lp_build_context *bld, + LLVMValueRef a); + +LLVMValueRef +lp_build_exp2(struct lp_build_context *bld, + LLVMValueRef a); + +LLVMValueRef +lp_build_log2(struct lp_build_context *bld, + LLVMValueRef a); + #endif /* !LP_BLD_ARIT_H */ -- cgit v1.2.3