Revert "remove LinearTransform from libutils"
This reverts commit d4d6167f614a9001d9827a8634a26b5e9445a22c.
Bug: 36206160
Test: Fugu compiles, didn't before the revert
Change-Id: I2b0d3a05546ee2605555a9aa7ae028f2baeaf439
(cherry picked from commit b80f086f69a4bc2e51d1f94ae58d7ba6b20514c4)
diff --git a/libs/common_time/Android.mk b/libs/common_time/Android.mk
index 636f057..1fec504 100644
--- a/libs/common_time/Android.mk
+++ b/libs/common_time/Android.mk
@@ -15,8 +15,7 @@
clock_recovery.cpp \
common_clock.cpp \
main.cpp \
- utils.cpp \
- LinearTransform.cpp
+ utils.cpp
# Uncomment to enable vesbose logging and debug service.
#TIME_SERVICE_DEBUG=true
diff --git a/libs/common_time/LinearTransform.cpp b/libs/common_time/LinearTransform.cpp
deleted file mode 100644
index 6730855..0000000
--- a/libs/common_time/LinearTransform.cpp
+++ /dev/null
@@ -1,281 +0,0 @@
-/*
- * Copyright (C) 2011 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#define __STDC_LIMIT_MACROS
-
-#include "LinearTransform.h"
-#include <assert.h>
-
-
-// disable sanitize as these functions may intentionally overflow (see comments below).
-// the ifdef can be removed when host builds use clang.
-#if defined(__clang__)
-#define ATTRIBUTE_NO_SANITIZE_INTEGER __attribute__((no_sanitize("integer")))
-#else
-#define ATTRIBUTE_NO_SANITIZE_INTEGER
-#endif
-
-namespace android {
-
-// sanitize failure with T = int32_t and x = 0x80000000
-template<class T>
-ATTRIBUTE_NO_SANITIZE_INTEGER
-static inline T ABS(T x) { return (x < 0) ? -x : x; }
-
-// Static math methods involving linear transformations
-// remote sanitize failure on overflow case.
-ATTRIBUTE_NO_SANITIZE_INTEGER
-static bool scale_u64_to_u64(
- uint64_t val,
- uint32_t N,
- uint32_t D,
- uint64_t* res,
- bool round_up_not_down) {
- uint64_t tmp1, tmp2;
- uint32_t r;
-
- assert(res);
- assert(D);
-
- // Let U32(X) denote a uint32_t containing the upper 32 bits of a 64 bit
- // integer X.
- // Let L32(X) denote a uint32_t containing the lower 32 bits of a 64 bit
- // integer X.
- // Let X[A, B] with A <= B denote bits A through B of the integer X.
- // Let (A | B) denote the concatination of two 32 bit ints, A and B.
- // IOW X = (A | B) => U32(X) == A && L32(X) == B
- //
- // compute M = val * N (a 96 bit int)
- // ---------------------------------
- // tmp2 = U32(val) * N (a 64 bit int)
- // tmp1 = L32(val) * N (a 64 bit int)
- // which means
- // M = val * N = (tmp2 << 32) + tmp1
- tmp2 = (val >> 32) * N;
- tmp1 = (val & UINT32_MAX) * N;
-
- // compute M[32, 95]
- // tmp2 = tmp2 + U32(tmp1)
- // = (U32(val) * N) + U32(L32(val) * N)
- // = M[32, 95]
- tmp2 += tmp1 >> 32;
-
- // if M[64, 95] >= D, then M/D has bits > 63 set and we have
- // an overflow.
- if ((tmp2 >> 32) >= D) {
- *res = UINT64_MAX;
- return false;
- }
-
- // Divide. Going in we know
- // tmp2 = M[32, 95]
- // U32(tmp2) < D
- r = tmp2 % D;
- tmp2 /= D;
-
- // At this point
- // tmp1 = L32(val) * N
- // tmp2 = M[32, 95] / D
- // = (M / D)[32, 95]
- // r = M[32, 95] % D
- // U32(tmp2) = 0
- //
- // compute tmp1 = (r | M[0, 31])
- tmp1 = (tmp1 & UINT32_MAX) | ((uint64_t)r << 32);
-
- // Divide again. Keep the remainder around in order to round properly.
- r = tmp1 % D;
- tmp1 /= D;
-
- // At this point
- // tmp2 = (M / D)[32, 95]
- // tmp1 = (M / D)[ 0, 31]
- // r = M % D
- // U32(tmp1) = 0
- // U32(tmp2) = 0
-
- // Pack the result and deal with the round-up case (As well as the
- // remote possiblility over overflow in such a case).
- *res = (tmp2 << 32) | tmp1;
- if (r && round_up_not_down) {
- ++(*res);
- if (!(*res)) {
- *res = UINT64_MAX;
- return false;
- }
- }
-
- return true;
-}
-
-// at least one known sanitize failure (see comment below)
-ATTRIBUTE_NO_SANITIZE_INTEGER
-static bool linear_transform_s64_to_s64(
- int64_t val,
- int64_t basis1,
- int32_t N,
- uint32_t D,
- bool invert_frac,
- int64_t basis2,
- int64_t* out) {
- uint64_t scaled, res;
- uint64_t abs_val;
- bool is_neg;
-
- if (!out)
- return false;
-
- // Compute abs(val - basis_64). Keep track of whether or not this delta
- // will be negative after the scale opertaion.
- if (val < basis1) {
- is_neg = true;
- abs_val = basis1 - val;
- } else {
- is_neg = false;
- abs_val = val - basis1;
- }
-
- if (N < 0)
- is_neg = !is_neg;
-
- if (!scale_u64_to_u64(abs_val,
- invert_frac ? D : ABS(N),
- invert_frac ? ABS(N) : D,
- &scaled,
- is_neg))
- return false; // overflow/undeflow
-
- // if scaled is >= 0x8000<etc>, then we are going to overflow or
- // underflow unless ABS(basis2) is large enough to pull us back into the
- // non-overflow/underflow region.
- if (scaled & INT64_MIN) {
- if (is_neg && (basis2 < 0))
- return false; // certain underflow
-
- if (!is_neg && (basis2 >= 0))
- return false; // certain overflow
-
- if (ABS(basis2) <= static_cast<int64_t>(scaled & INT64_MAX))
- return false; // not enough
-
- // Looks like we are OK
- *out = (is_neg ? (-scaled) : scaled) + basis2;
- } else {
- // Scaled fits within signed bounds, so we just need to check for
- // over/underflow for two signed integers. Basically, if both scaled
- // and basis2 have the same sign bit, and the result has a different
- // sign bit, then we have under/overflow. An easy way to compute this
- // is
- // (scaled_signbit XNOR basis_signbit) &&
- // (scaled_signbit XOR res_signbit)
- // ==
- // (scaled_signbit XOR basis_signbit XOR 1) &&
- // (scaled_signbit XOR res_signbit)
-
- if (is_neg)
- scaled = -scaled; // known sanitize failure
- res = scaled + basis2;
-
- if ((scaled ^ basis2 ^ INT64_MIN) & (scaled ^ res) & INT64_MIN)
- return false;
-
- *out = res;
- }
-
- return true;
-}
-
-bool LinearTransform::doForwardTransform(int64_t a_in, int64_t* b_out) const {
- if (0 == a_to_b_denom)
- return false;
-
- return linear_transform_s64_to_s64(a_in,
- a_zero,
- a_to_b_numer,
- a_to_b_denom,
- false,
- b_zero,
- b_out);
-}
-
-bool LinearTransform::doReverseTransform(int64_t b_in, int64_t* a_out) const {
- if (0 == a_to_b_numer)
- return false;
-
- return linear_transform_s64_to_s64(b_in,
- b_zero,
- a_to_b_numer,
- a_to_b_denom,
- true,
- a_zero,
- a_out);
-}
-
-template <class T> void LinearTransform::reduce(T* N, T* D) {
- T a, b;
- if (!N || !D || !(*D)) {
- assert(false);
- return;
- }
-
- a = *N;
- b = *D;
-
- if (a == 0) {
- *D = 1;
- return;
- }
-
- // This implements Euclid's method to find GCD.
- if (a < b) {
- T tmp = a;
- a = b;
- b = tmp;
- }
-
- while (1) {
- // a is now the greater of the two.
- const T remainder = a % b;
- if (remainder == 0) {
- *N /= b;
- *D /= b;
- return;
- }
- // by swapping remainder and b, we are guaranteeing that a is
- // still the greater of the two upon entrance to the loop.
- a = b;
- b = remainder;
- }
-};
-
-template void LinearTransform::reduce<uint64_t>(uint64_t* N, uint64_t* D);
-template void LinearTransform::reduce<uint32_t>(uint32_t* N, uint32_t* D);
-
-// sanitize failure if *N = 0x80000000
-ATTRIBUTE_NO_SANITIZE_INTEGER
-void LinearTransform::reduce(int32_t* N, uint32_t* D) {
- if (N && D && *D) {
- if (*N < 0) {
- *N = -(*N);
- reduce(reinterpret_cast<uint32_t*>(N), D);
- *N = -(*N);
- } else {
- reduce(reinterpret_cast<uint32_t*>(N), D);
- }
- }
-}
-
-} // namespace android
diff --git a/libs/common_time/LinearTransform.h b/libs/common_time/LinearTransform.h
deleted file mode 100644
index bf6ab8e..0000000
--- a/libs/common_time/LinearTransform.h
+++ /dev/null
@@ -1,64 +0,0 @@
-/*
- * Copyright (C) 2011 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef _LINEAR_TRANSFORM_H
-#define _LINEAR_TRANSFORM_H
-
-#include <stdint.h>
-
-namespace android {
-
-// LinearTransform defines a structure which hold the definition of a
-// transformation from single dimensional coordinate system A into coordinate
-// system B (and back again). Values in A and in B are 64 bit, the linear
-// scale factor is expressed as a rational number using two 32 bit values.
-//
-// Specifically, let
-// f(a) = b
-// F(b) = f^-1(b) = a
-// then
-//
-// f(a) = (((a - a_zero) * a_to_b_numer) / a_to_b_denom) + b_zero;
-//
-// and
-//
-// F(b) = (((b - b_zero) * a_to_b_denom) / a_to_b_numer) + a_zero;
-//
-struct LinearTransform {
- int64_t a_zero;
- int64_t b_zero;
- int32_t a_to_b_numer;
- uint32_t a_to_b_denom;
-
- // Transform from A->B
- // Returns true on success, or false in the case of a singularity or an
- // overflow.
- bool doForwardTransform(int64_t a_in, int64_t* b_out) const;
-
- // Transform from B->A
- // Returns true on success, or false in the case of a singularity or an
- // overflow.
- bool doReverseTransform(int64_t b_in, int64_t* a_out) const;
-
- // Helpers which will reduce the fraction N/D using Euclid's method.
- template <class T> static void reduce(T* N, T* D);
- static void reduce(int32_t* N, uint32_t* D);
-};
-
-
-}
-
-#endif // _LINEAR_TRANSFORM_H
diff --git a/libs/common_time/clock_recovery.h b/libs/common_time/clock_recovery.h
index 8066a39..278a75e 100644
--- a/libs/common_time/clock_recovery.h
+++ b/libs/common_time/clock_recovery.h
@@ -19,10 +19,9 @@
#include <stdint.h>
#include <common_time/ICommonClock.h>
+#include <utils/LinearTransform.h>
#include <utils/threads.h>
-#include "LinearTransform.h"
-
#ifdef TIME_SERVICE_DEBUG
#include "diag_thread.h"
#endif
diff --git a/libs/common_time/common_clock.cpp b/libs/common_time/common_clock.cpp
index aed52f1..ee326e1 100644
--- a/libs/common_time/common_clock.cpp
+++ b/libs/common_time/common_clock.cpp
@@ -23,6 +23,7 @@
#include <stdint.h>
#include <utils/Errors.h>
+#include <utils/LinearTransform.h>
#include "common_clock.h"
diff --git a/libs/common_time/common_clock.h b/libs/common_time/common_clock.h
index 5e4e5f5..b786fdc 100644
--- a/libs/common_time/common_clock.h
+++ b/libs/common_time/common_clock.h
@@ -20,10 +20,9 @@
#include <stdint.h>
#include <utils/Errors.h>
+#include <utils/LinearTransform.h>
#include <utils/threads.h>
-#include "LinearTransform.h"
-
namespace android {
class CommonClock {
