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-rw-r--r--libpixelflinger/fixed.cpp339
1 files changed, 0 insertions, 339 deletions
diff --git a/libpixelflinger/fixed.cpp b/libpixelflinger/fixed.cpp
deleted file mode 100644
index 5b920628b..000000000
--- a/libpixelflinger/fixed.cpp
+++ /dev/null
@@ -1,339 +0,0 @@
-/* libs/pixelflinger/fixed.cpp
-**
-** Copyright 2006, 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.
-*/
-
-#include <stdio.h>
-
-#include <private/pixelflinger/ggl_context.h>
-#include <private/pixelflinger/ggl_fixed.h>
-
-
-// ------------------------------------------------------------------------
-
-int32_t gglRecipQNormalized(int32_t x, int* exponent)
-{
- const int32_t s = x>>31;
- uint32_t a = s ? -x : x;
-
- // the result will overflow, so just set it to the biggest/inf value
- if (ggl_unlikely(a <= 2LU)) {
- *exponent = 0;
- return s ? FIXED_MIN : FIXED_MAX;
- }
-
- // Newton-Raphson iteration:
- // x = r*(2 - a*r)
-
- const int32_t lz = gglClz(a);
- a <<= lz; // 0.32
- uint32_t r = a;
- // note: if a == 0x80000000, this means x was a power-of-2, in this
- // case we don't need to compute anything. We get the reciprocal for
- // (almost) free.
- if (a != 0x80000000) {
- r = (0x2E800 << (30-16)) - (r>>(2-1)); // 2.30, r = 2.90625 - 2*a
- // 0.32 + 2.30 = 2.62 -> 2.30
- // 2.30 + 2.30 = 4.60 -> 2.30
- r = (((2LU<<30) - uint32_t((uint64_t(a)*r) >> 32)) * uint64_t(r)) >> 30;
- r = (((2LU<<30) - uint32_t((uint64_t(a)*r) >> 32)) * uint64_t(r)) >> 30;
- }
-
- // shift right 1-bit to make room for the sign bit
- *exponent = 30-lz-1;
- r >>= 1;
- return s ? -r : r;
-}
-
-int32_t gglRecipQ(GGLfixed x, int q)
-{
- int shift;
- x = gglRecipQNormalized(x, &shift);
- shift += 16-q;
- x += 1L << (shift-1); // rounding
- x >>= shift;
- return x;
-}
-
-// ------------------------------------------------------------------------
-
-GGLfixed gglFastDivx(GGLfixed n, GGLfixed d)
-{
- if ((d>>24) && ((d>>24)+1)) {
- n >>= 8;
- d >>= 8;
- }
- return gglMulx(n, gglRecip(d));
-}
-
-// ------------------------------------------------------------------------
-
-static const GGLfixed ggl_sqrt_reciproc_approx_tab[8] = {
- // 1/sqrt(x) with x = 1-N/16, N=[8...1]
- 0x16A09, 0x15555, 0x143D1, 0x134BF, 0x1279A, 0x11C01, 0x111AC, 0x10865
-};
-
-GGLfixed gglSqrtRecipx(GGLfixed x)
-{
- if (x == 0) return FIXED_MAX;
- if (x == FIXED_ONE) return x;
- const GGLfixed a = x;
- const int32_t lz = gglClz(x);
- x = ggl_sqrt_reciproc_approx_tab[(a>>(28-lz))&0x7];
- const int32_t exp = lz - 16;
- if (exp <= 0) x >>= -exp>>1;
- else x <<= (exp>>1) + (exp & 1);
- if (exp & 1) {
- x = gglMulx(x, ggl_sqrt_reciproc_approx_tab[0])>>1;
- }
- // 2 Newton-Raphson iterations: x = x/2*(3-(a*x)*x)
- x = gglMulx((x>>1),(0x30000 - gglMulx(gglMulx(a,x),x)));
- x = gglMulx((x>>1),(0x30000 - gglMulx(gglMulx(a,x),x)));
- return x;
-}
-
-GGLfixed gglSqrtx(GGLfixed a)
-{
- // Compute a full precision square-root (24 bits accuracy)
- GGLfixed r = 0;
- GGLfixed bit = 0x800000;
- int32_t bshift = 15;
- do {
- GGLfixed temp = bit + (r<<1);
- if (bshift >= 8) temp <<= (bshift-8);
- else temp >>= (8-bshift);
- if (a >= temp) {
- r += bit;
- a -= temp;
- }
- bshift--;
- } while (bit>>=1);
- return r;
-}
-
-// ------------------------------------------------------------------------
-
-static const GGLfixed ggl_log_approx_tab[] = {
- // -ln(x)/ln(2) with x = N/16, N=[8...16]
- 0xFFFF, 0xd47f, 0xad96, 0x8a62, 0x6a3f, 0x4caf, 0x3151, 0x17d6, 0x0000
-};
-
-static const GGLfixed ggl_alog_approx_tab[] = { // domain [0 - 1.0]
- 0xffff, 0xeac0, 0xd744, 0xc567, 0xb504, 0xa5fe, 0x9837, 0x8b95, 0x8000
-};
-
-GGLfixed gglPowx(GGLfixed x, GGLfixed y)
-{
- // prerequisite: 0 <= x <= 1, and y >=0
-
- // pow(x,y) = 2^(y*log2(x))
- // = 2^(y*log2(x*(2^exp)*(2^-exp))))
- // = 2^(y*(log2(X)-exp))
- // = 2^(log2(X)*y - y*exp)
- // = 2^( - (-log2(X)*y + y*exp) )
-
- int32_t exp = gglClz(x) - 16;
- GGLfixed f = x << exp;
- x = (f & 0x0FFF)<<4;
- f = (f >> 12) & 0x7;
- GGLfixed p = gglMulAddx(
- ggl_log_approx_tab[f+1] - ggl_log_approx_tab[f], x,
- ggl_log_approx_tab[f]);
- p = gglMulAddx(p, y, y*exp);
- exp = gglFixedToIntFloor(p);
- if (exp < 31) {
- p = gglFracx(p);
- x = (p & 0x1FFF)<<3;
- p >>= 13;
- p = gglMulAddx(
- ggl_alog_approx_tab[p+1] - ggl_alog_approx_tab[p], x,
- ggl_alog_approx_tab[p]);
- p >>= exp;
- } else {
- p = 0;
- }
- return p;
- // ( powf((a*65536.0f), (b*65536.0f)) ) * 65536.0f;
-}
-
-// ------------------------------------------------------------------------
-
-int32_t gglDivQ(GGLfixed n, GGLfixed d, int32_t i)
-{
- //int32_t r =int32_t((int64_t(n)<<i)/d);
- const int32_t ds = n^d;
- if (n<0) n = -n;
- if (d<0) d = -d;
- int nd = gglClz(d) - gglClz(n);
- i += nd + 1;
- if (nd > 0) d <<= nd;
- else n <<= -nd;
- uint32_t q = 0;
-
- int j = i & 7;
- i >>= 3;
-
- // gcc deals with the code below pretty well.
- // we get 3.75 cycles per bit in the main loop
- // and 8 cycles per bit in the termination loop
- if (ggl_likely(i)) {
- n -= d;
- do {
- q <<= 8;
- if (n>=0) q |= 128;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 64;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 32;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 16;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 8;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 4;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 2;
- else n += d;
- n = n*2 - d;
- if (n>=0) q |= 1;
- else n += d;
-
- if (--i == 0)
- goto finish;
-
- n = n*2 - d;
- } while(true);
- do {
- q <<= 1;
- n = n*2 - d;
- if (n>=0) q |= 1;
- else n += d;
- finish: ;
- } while (j--);
- return (ds<0) ? -q : q;
- }
-
- n -= d;
- if (n>=0) q |= 1;
- else n += d;
- j--;
- goto finish;
-}
-
-// ------------------------------------------------------------------------
-
-// assumes that the int32_t values of a, b, and c are all positive
-// use when both a and b are larger than c
-
-template <typename T>
-static inline void swap(T& a, T& b) {
- T t(a);
- a = b;
- b = t;
-}
-
-static __attribute__((noinline))
-int32_t slow_muldiv(uint32_t a, uint32_t b, uint32_t c)
-{
- // first we compute a*b as a 64-bit integer
- // (GCC generates umull with the code below)
- uint64_t ab = uint64_t(a)*b;
- uint32_t hi = ab>>32;
- uint32_t lo = ab;
- uint32_t result;
-
- // now perform the division
- if (hi >= c) {
- overflow:
- result = 0x7fffffff; // basic overflow
- } else if (hi == 0) {
- result = lo/c; // note: c can't be 0
- if ((result >> 31) != 0) // result must fit in 31 bits
- goto overflow;
- } else {
- uint32_t r = hi;
- int bits = 31;
- result = 0;
- do {
- r = (r << 1) | (lo >> 31);
- lo <<= 1;
- result <<= 1;
- if (r >= c) {
- r -= c;
- result |= 1;
- }
- } while (bits--);
- }
- return int32_t(result);
-}
-
-// assumes a >= 0 and c >= b >= 0
-static inline
-int32_t quick_muldiv(int32_t a, int32_t b, int32_t c)
-{
- int32_t r = 0, q = 0, i;
- int leading = gglClz(a);
- i = 32 - leading;
- a <<= leading;
- do {
- r <<= 1;
- if (a < 0)
- r += b;
- a <<= 1;
- q <<= 1;
- if (r >= c) {
- r -= c;
- q++;
- }
- asm(""::); // gcc generates better code this way
- if (r >= c) {
- r -= c;
- q++;
- }
- }
- while (--i);
- return q;
-}
-
-// this function computes a*b/c with 64-bit intermediate accuracy
-// overflows (e.g. division by 0) are handled and return INT_MAX
-
-int32_t gglMulDivi(int32_t a, int32_t b, int32_t c)
-{
- int32_t result;
- int32_t sign = a^b^c;
-
- if (a < 0) a = -a;
- if (b < 0) b = -b;
- if (c < 0) c = -c;
-
- if (a < b) {
- swap(a, b);
- }
-
- if (b <= c) result = quick_muldiv(a, b, c);
- else result = slow_muldiv((uint32_t)a, (uint32_t)b, (uint32_t)c);
-
- if (sign < 0)
- result = -result;
-
- return result;
-}
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