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-rw-r--r--pl/math/sv_log2_3u.c73
1 files changed, 0 insertions, 73 deletions
diff --git a/pl/math/sv_log2_3u.c b/pl/math/sv_log2_3u.c
deleted file mode 100644
index 0775a39cc85d..000000000000
--- a/pl/math/sv_log2_3u.c
+++ /dev/null
@@ -1,73 +0,0 @@
-/*
- * Double-precision SVE log2 function.
- *
- * Copyright (c) 2022-2023, Arm Limited.
- * SPDX-License-Identifier: MIT OR Apache-2.0 WITH LLVM-exception
- */
-
-#include "sv_math.h"
-#include "pl_sig.h"
-#include "pl_test.h"
-#include "poly_sve_f64.h"
-
-#define N (1 << V_LOG2_TABLE_BITS)
-#define Off 0x3fe6900900000000
-#define Max (0x7ff0000000000000)
-#define Min (0x0010000000000000)
-#define Thresh (0x7fe0000000000000) /* Max - Min. */
-
-static svfloat64_t NOINLINE
-special_case (svfloat64_t x, svfloat64_t y, svbool_t cmp)
-{
- return sv_call_f64 (log2, x, y, cmp);
-}
-
-/* Double-precision SVE log2 routine.
- Implements the same algorithm as AdvSIMD log10, with coefficients and table
- entries scaled in extended precision.
- The maximum observed error is 2.58 ULP:
- SV_NAME_D1 (log2)(0x1.0b556b093869bp+0) got 0x1.fffb34198d9dap-5
- want 0x1.fffb34198d9ddp-5. */
-svfloat64_t SV_NAME_D1 (log2) (svfloat64_t x, const svbool_t pg)
-{
- svuint64_t ix = svreinterpret_u64 (x);
- svbool_t special = svcmpge (pg, svsub_x (pg, ix, Min), Thresh);
-
- /* x = 2^k z; where z is in range [Off,2*Off) and exact.
- The range is split into N subintervals.
- The ith subinterval contains z and c is near its center. */
- svuint64_t tmp = svsub_x (pg, ix, Off);
- svuint64_t i = svlsr_x (pg, tmp, 51 - V_LOG2_TABLE_BITS);
- i = svand_x (pg, i, (N - 1) << 1);
- svfloat64_t k = svcvt_f64_x (pg, svasr_x (pg, svreinterpret_s64 (tmp), 52));
- svfloat64_t z = svreinterpret_f64 (
- svsub_x (pg, ix, svand_x (pg, tmp, 0xfffULL << 52)));
-
- svfloat64_t invc = svld1_gather_index (pg, &__v_log2_data.table[0].invc, i);
- svfloat64_t log2c
- = svld1_gather_index (pg, &__v_log2_data.table[0].log2c, i);
-
- /* log2(x) = log1p(z/c-1)/log(2) + log2(c) + k. */
-
- svfloat64_t r = svmad_x (pg, invc, z, -1.0);
- svfloat64_t w = svmla_x (pg, log2c, r, __v_log2_data.invln2);
-
- svfloat64_t r2 = svmul_x (pg, r, r);
- svfloat64_t y = sv_pw_horner_4_f64_x (pg, r, r2, __v_log2_data.poly);
- w = svadd_x (pg, k, w);
-
- if (unlikely (svptest_any (pg, special)))
- return special_case (x, svmla_x (svnot_z (pg, special), w, r2, y),
- special);
- return svmla_x (pg, w, r2, y);
-}
-
-PL_SIG (SV, D, 1, log2, 0.01, 11.1)
-PL_TEST_ULP (SV_NAME_D1 (log2), 2.09)
-PL_TEST_EXPECT_FENV_ALWAYS (SV_NAME_D1 (log2))
-PL_TEST_INTERVAL (SV_NAME_D1 (log2), -0.0, -0x1p126, 1000)
-PL_TEST_INTERVAL (SV_NAME_D1 (log2), 0.0, 0x1p-126, 4000)
-PL_TEST_INTERVAL (SV_NAME_D1 (log2), 0x1p-126, 0x1p-23, 50000)
-PL_TEST_INTERVAL (SV_NAME_D1 (log2), 0x1p-23, 1.0, 50000)
-PL_TEST_INTERVAL (SV_NAME_D1 (log2), 1.0, 100, 50000)
-PL_TEST_INTERVAL (SV_NAME_D1 (log2), 100, inf, 50000)