--- /dev/null
+Taken from upstream PR: https://github.com/xbmc/xbmc/pull/3760
+
+Signed-off-by: Bernd Kuhls <bernd.kuhls@t-online.de>
+
+
+From 7388e8be7cd5e78100532ebf0dba15dccb7b03f8 Mon Sep 17 00:00:00 2001
+From: Ben Avison <bavison@riscosopen.org>
+Date: Tue, 3 Dec 2013 15:51:39 +0000
+Subject: [PATCH] Faster and simpler portable implementation of
+ MathUtils::round_int().
+
+Much as I like a bit of inline assembler, I have also removed the ARM versions
+of MathUtils::truncate_int() and MathUtils::round_int(). The former was just
+how any sane compiler should have assembled a cast from double to signed int
+anyway. The latter was a much too complicated way to achieve the desired
+effect, and was switched out in most ARM builds anyway in favour of the old
+portable implementation that used floor().
+
+Verified that MathUtils::test() still passes, and that GCC is now able to
+inline MathUtils::round_int(), where it didn't previously.
+
+I tested on a Raspberry Pi with the default theme, displaying the front page
+with the RSS ticker enabled. This saturates the CPU, so I'm measuring the
+improvement using the debug window's FPS figure. This patch improves this from
+~50.8 FPS to ~52.6 FPS.
+---
+ xbmc/utils/MathUtils.h | 129 +++++++++++++++++++++++--------------------------
+ 1 file changed, 61 insertions(+), 68 deletions(-)
+
+diff --git a/xbmc/utils/MathUtils.h b/xbmc/utils/MathUtils.h
+index 96af9f4..0dae77d 100644
+--- a/xbmc/utils/MathUtils.h
++++ b/xbmc/utils/MathUtils.h
+@@ -34,17 +34,13 @@
+
+ #if defined(__ppc__) || \
+ defined(__powerpc__) || \
+- (defined(TARGET_DARWIN_IOS) && defined(__llvm__)) || \
+- (defined(TARGET_ANDROID) && defined(__arm__)) || \
+- defined(TARGET_RASPBERRY_PI)
++ defined(__arm__)
+ #define DISABLE_MATHUTILS_ASM_ROUND_INT
+ #endif
+
+ #if defined(__ppc__) || \
+ defined(__powerpc__) || \
+- (defined(TARGET_DARWIN) && defined(__llvm__)) || \
+- (defined(TARGET_ANDROID) && defined(__arm__)) || \
+- defined(TARGET_RASPBERRY_PI)
++ defined(__arm__)
+ #define DISABLE_MATHUTILS_ASM_TRUNCATE_INT
+ #endif
+
+@@ -73,60 +69,63 @@
+ {
+ assert(x > static_cast<double>(INT_MIN / 2) - 1.0);
+ assert(x < static_cast<double>(INT_MAX / 2) + 1.0);
+- const float round_to_nearest = 0.5f;
+- int i;
+
+ #if defined(DISABLE_MATHUTILS_ASM_ROUND_INT)
+- i = floor(x + round_to_nearest);
+-
+-#elif defined(__arm__)
+- // From 'ARM-v7-M Architecture Reference Manual' page A7-569:
+- // "The floating-point to integer operation (vcvt) [normally] uses the Round towards Zero rounding mode"
+- // Because of this...we must use some less-than-straightforward logic to perform this operation without
+- // changing the rounding mode flags
+-
+- /* The assembly below implements the following logic:
+- if (x < 0)
+- inc = -0.5f
+- else
+- inc = 0.5f
+- int_val = trunc(x+inc);
+- err = x - int_val;
+- if (err == 0.5f)
+- int_val++;
+- return int_val;
+- */
++ /* This implementation warrants some further explanation.
++ *
++ * First, a couple of notes on rounding:
++ * 1) C casts from float/double to integer round towards zero.
++ * 2) Float/double additions are rounded according to the normal rules,
++ * in other words: on some architectures, it's fixed at compile-time,
++ * and on others it can be set using fesetround()). The following
++ * analysis assumes round-to-nearest with ties rounding to even. This
++ * is a fairly sensible choice, and is the default with ARM VFP.
++ *
++ * What this function wants is round-to-nearest with ties rounding to
++ * +infinity. This isn't an IEEE rounding mode, even if we could guarantee
++ * that all architectures supported fesetround(), which they don't. Instead,
++ * this adds an offset of 2147483648.5 (= 0x80000000.8p0), then casts to
++ * an unsigned int (crucially, all possible inputs are now in a range where
++ * round to zero acts the same as round to -infinity) and then subtracts
++ * 0x80000000 in the integer domain. The 0.5 component of the offset
++ * converts what is effectively a round down into a round to nearest, with
++ * ties rounding up, as desired.
++ *
++ * There is a catch, that because there is a double rounding, there is a
++ * small region where the input falls just *below* a tie, where the addition
++ * of the offset causes a round *up* to an exact integer, due to the finite
++ * level of precision available in floating point. You need to be aware of
++ * this when calling this function, although at present it is not believed
++ * that XBMC ever attempts to round numbers in this window.
++ *
++ * It is worth proving the size of the affected window. Recall that double
++ * precision employs a mantissa of 52 bits.
++ * 1) For all inputs -0.5 <= x <= INT_MAX
++ * Once the offset is applied, the most significant binary digit in the
++ * floating-point representation is +2^31.
++ * At this magnitude, the smallest step representable in double precision
++ * is 2^31 / 2^52 = 0.000000476837158203125
++ * So the size of the range which is rounded up due to the addition is
++ * half the size of this step, or 0.0000002384185791015625
++ *
++ * 2) For all inputs INT_MIN/2 < x < -0.5
++ * Once the offset is applied, the most significant binary digit in the
++ * floating-point representation is +2^30.
++ * At this magnitude, the smallest step representable in double precision
++ * is 2^30 / 2^52 = 0.0000002384185791015625
++ * So the size of the range which is rounded up due to the addition is
++ * half the size of this step, or 0.00000011920928955078125
++ *
++ * 3) For all inputs INT_MIN <= x <= INT_MIN/2
++ * The representation once the offset is applied has equal or greater
++ * precision than the input, so the addition does not cause rounding.
++ */
++ return ((unsigned int) (x + 0x80000000.8p0)) - 0x80000000;
+
+- __asm__ __volatile__ (
+-#if defined(__ARM_PCS_VFP)
+- "fconstd d1,#%G[rnd_val] \n\t" // Copy round_to_nearest into a working register (d1 = 0.5)
+ #else
+- "vmov.F64 d1,%[rnd_val] \n\t"
+-#endif
+- "fcmpezd %P[value] \n\t" // Check value against zero (value == 0?)
+- "fmstat \n\t" // Copy the floating-point status flags into the general-purpose status flags
+- "it mi \n\t"
+- "vnegmi.F64 d1, d1 \n\t" // if N-flag is set, negate round_to_nearest (if (value < 0) d1 = -1 * d1)
+- "vadd.F64 d1,%P[value],d1 \n\t" // Add round_to_nearest to value, store result in working register (d1 += value)
+- "vcvt.S32.F64 s3,d1 \n\t" // Truncate(round towards zero) (s3 = (int)d1)
+- "vmov %[result],s3 \n\t" // Store the integer result in a general-purpose register (result = s3)
+- "vcvt.F64.S32 d1,s3 \n\t" // Convert back to floating-point (d1 = (double)s3)
+- "vsub.F64 d1,%P[value],d1 \n\t" // Calculate the error (d1 = value - d1)
+-#if defined(__ARM_PCS_VFP)
+- "fconstd d2,#%G[rnd_val] \n\t" // d2 = 0.5;
+-#else
+- "vmov.F64 d2,%[rnd_val] \n\t"
+-#endif
+- "fcmped d1, d2 \n\t" // (d1 == 0.5?)
+- "fmstat \n\t" // Copy the floating-point status flags into the general-purpose status flags
+- "it eq \n\t"
+- "addeq %[result],#1 \n\t" // (if (d1 == d2) result++;)
+- : [result] "=r"(i) // Outputs
+- : [rnd_val] "Dv" (round_to_nearest), [value] "w"(x) // Inputs
+- : "d1", "d2", "s3" // Clobbers
+- );
+-
+-#elif defined(__SSE2__)
++ const float round_to_nearest = 0.5f;
++ int i;
++#if defined(__SSE2__)
+ const float round_dn_to_nearest = 0.4999999f;
+ i = (x > 0) ? _mm_cvttsd_si32(_mm_set_sd(x + round_to_nearest)) : _mm_cvttsd_si32(_mm_set_sd(x - round_dn_to_nearest));
+
+@@ -150,8 +149,8 @@
+ );
+
+ #endif
+-
+ return i;
++#endif
+ }
+
+ /*! \brief Truncate to nearest integer.
+@@ -165,20 +164,13 @@
+ {
+ assert(x > static_cast<double>(INT_MIN / 2) - 1.0);
+ assert(x < static_cast<double>(INT_MAX / 2) + 1.0);
+- int i;
+
+ #if defined(DISABLE_MATHUTILS_ASM_TRUNCATE_INT)
+- return i = (int)x;
+-
+-#elif defined(__arm__)
+- __asm__ __volatile__ (
+- "vcvt.S32.F64 %[result],%P[value] \n\t" // Truncate(round towards zero) and store the result
+- : [result] "=w"(i) // Outputs
+- : [value] "w"(x) // Inputs
+- );
+- return i;
++ return x;
+
+-#elif defined(TARGET_WINDOWS)
++#else
++ int i;
++#if defined(TARGET_WINDOWS)
+ const float round_towards_m_i = -0.5f;
+ __asm
+ {
+@@ -204,6 +196,7 @@
+ if (x < 0)
+ i = -i;
+ return (i);
++#endif
+ }
+
+ inline int64_t abs(int64_t a)
+--
+1.9.1
+
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