diff options
| author |  Abseil Team <absl-team@google.com> | 2021-01-29 12:09:30 -0800 |
|---|---|---|
| committer |  CJ Johnson <johnsoncj@google.com> | 2021-01-29 15:12:57 -0500 |
| commit | a9a49560208484f1f99efdde889da6147e8722fe (patch) | |
| tree | 72b0dbfed7927df49820ce1a99a0db86aaafc5cf /absl/strings/internal/memutil.h | |
| parent | af39e133059928cfcdeea0592434720897f20173 (diff) | |
Export of internal Abseil changes
--
c68f1886f5e8fd90eb0c2d2e68feaf00a7cdacda by CJ Johnson <johnsoncj@google.com>:
Introduce absl::Cleanup to the OSS repo
PiperOrigin-RevId: 354583156
--
17030cf388e10f7eb959e3e566326d1072ce392e by Abseil Team <absl-team@google.com>:
Internal change only
PiperOrigin-RevId: 354574953
--
e979d7236d4f3252e79ddda6739b67a9a326bf6d by CJ Johnson <johnsoncj@google.com>:
Internal change
PiperOrigin-RevId: 354545297
--
7ea02b3783f7f49ef97d86a8f6580a19cc57df14 by Abseil Team <absl-team@google.com>:
Pre-allocate memory for vectors where the size is known.
PiperOrigin-RevId: 354344576
--
9246c7cb11f1d6444f79ebe25acc69a8a9b870e0 by Matt Kulukundis <kfm@google.com>:
Add support for Elbrus 2000 (e2k)
Import of https://github.com/abseil/abseil-cpp/pull/889
PiperOrigin-RevId: 354344013
--
0fc93d359cc1fb307552e917b37b7b2e7eed822f by Abseil Team <absl-team@google.com>:
Integrate CordRepRing logic into cord (but do not enable it)
PiperOrigin-RevId: 354312238
--
eda05622f7da71466723acb33403f783529df24b by Abseil Team <absl-team@google.com>:
Protect ignore diagnostic with "__has_warning".
PiperOrigin-RevId: 354112334
--
47716c5d8fb10efa4fdd801d28bac414c6f8ec32 by Abseil Team <absl-team@google.com>:
Rearrange InlinedVector copy constructor and destructor to treat
a few special cases inline and then tail-call a non-inlined routine
for the rest. In particular, we optimize for empty vectors in both
cases.
Added a couple of benchmarks that copy either an InlVec<int64> or
an InlVec<InlVec<int64>>.
Speed difference:
```
BM_CopyTrivial/0 0.92ns +- 0% 0.47ns +- 0% -48.91% (p=0.000 n=11+12)
BM_CopyTrivial/1 0.92ns +- 0% 1.15ns +- 0% +25.00% (p=0.000 n=10+9)
BM_CopyTrivial/8 8.57ns +- 0% 10.72ns +- 1% +25.16% (p=0.000 n=10+12)
BM_CopyNonTrivial/0 3.21ns +- 0% 0.70ns +- 0% -78.23% (p=0.000 n=12+10)
BM_CopyNonTrivial/1 5.88ns +- 1% 5.51ns +- 0% -6.28% (p=0.000 n=10+8)
BM_CopyNonTrivial/8 21.5ns +- 1% 15.2ns +- 2% -29.23% (p=0.000 n=12+12)
```
Note: the slowdowns are a few cycles which is expected given the procedure
call added in that case. We decided this is a good tradeoff given the code
size reductions and the more significant speedups for empty vectors.
Size difference (as measured by nm):
```
BM_CopyTrivial from 1048 bytes to 326 bytes.
BM_CopyNonTrivial from 749 bytes to 470 bytes.
```
Code size for a large binary drops by ~500KB (from 349415719 to 348906015 348906191).
All of the benchmarks that showed a significant difference:
Ones that improve with this CL:
```
BM_CopyNonTrivial/0 3.21ns +- 0% 0.70ns +- 0% -78.23% (p=0.000 n=12+10)
BM_InlinedVectorFillString/0 0.93ns +- 0% 0.24ns +- 0% -74.19% (p=0.000 n=12+10)
BM_InlinedVectorAssignments/1 10.5ns +- 0% 4.1ns +- 0% -60.64% (p=0.000 n=11+10)
BM_InlinedVectorAssignments/2 10.7ns +- 0% 4.4ns +- 0% -59.08% (p=0.000 n=11+11)
BM_CopyTrivial/0 0.92ns +- 0% 0.47ns +- 0% -48.91% (p=0.000 n=11+12)
BM_CopyNonTrivial/8 21.5ns +- 1% 15.2ns +- 2% -29.23% (p=0.000 n=12+12)
BM_StdVectorEmpty 0.47ns +- 1% 0.35ns +- 0% -24.73% (p=0.000 n=12+12)
BM_StdVectorSize 0.46ns +- 2% 0.35ns +- 0% -24.32% (p=0.000 n=12+12)
BM_SwapElements<LargeCopyableOnly>/0 3.44ns +- 0% 2.76ns +- 1% -19.83% (p=0.000 n=11+11)
BM_InlinedVectorFillRange/256 20.7ns +- 1% 17.8ns +- 0% -14.08% (p=0.000 n=12+9)
BM_CopyNonTrivial/1 5.88ns +- 1% 5.51ns +- 0% -6.28% (p=0.000 n=10+8)
BM_SwapElements<LargeCopyableMovable>/1 4.19ns +- 0% 3.95ns +- 1% -5.63% (p=0.000 n=11+12)
BM_SwapElements<LargeCopyableMovableSwappable>/1 4.18ns +- 0% 3.99ns +- 0% -4.70% (p=0.000 n=9+11)
BM_SwapElements<LargeCopyableMovable>/0 2.41ns +- 0% 2.31ns +- 0% -4.45% (p=0.000 n=12+12)
BM_InlinedVectorFillRange/64 8.25ns +- 0% 8.04ns +- 0% -2.51% (p=0.000 n=12+11)
BM_SwapElements<LargeCopyableOnly>/1 82.4ns +- 0% 81.5ns +- 0% -1.06% (p=0.000 n=12+12)
```
Ones that get worse with this CL:
```
BM_CopyTrivial/1 0.92ns +- 0% 1.15ns +- 0% +25.00% (p=0.000 n=10+9)
BM_CopyTrivial/8 8.57ns +- 0% 10.72ns +- 1% +25.16% (p=0.000 n=10+12)
BM_SwapElements<LargeCopyableMovableSwappable>/512 1.48ns +- 1% 1.66ns +- 1% +11.88% (p=0.000 n=12+12)
BM_InlinedVectorFillString/1 11.5ns +- 0% 12.8ns +- 1% +11.62% (p=0.000 n=12+11)
BM_SwapElements<LargeCopyableMovableSwappable>/64 1.48ns +- 2% 1.66ns +- 1% +11.66% (p=0.000 n=12+11)
BM_SwapElements<LargeCopyableMovableSwappable>/1k 1.48ns +- 1% 1.65ns +- 2% +11.32% (p=0.000 n=12+12)
BM_SwapElements<LargeCopyableMovable>/512 1.48ns +- 2% 1.58ns +- 4% +6.62% (p=0.000 n=11+12)
BM_SwapElements<LargeCopyableMovable>/1k 1.49ns +- 2% 1.58ns +- 3% +6.05% (p=0.000 n=12+12)
BM_SwapElements<LargeCopyableMovable>/64 1.48ns +- 2% 1.57ns +- 4% +6.04% (p=0.000 n=11+12)
BM_InlinedVectorFillRange/1 4.81ns +- 0% 5.05ns +- 0% +4.83% (p=0.000 n=11+11)
BM_InlinedVectorFillString/8 79.4ns +- 1% 83.1ns +- 1% +4.64% (p=0.000 n=10+12)
BM_StdVectorFillString/1 16.3ns +- 0% 16.6ns +- 0% +2.13% (p=0.000 n=11+8)
```
PiperOrigin-RevId: 353906786
--
8e26518b3cec9c598e5e9573c46c3bd1b03a67ef by Abseil Team <absl-team@google.com>:
Internal change
PiperOrigin-RevId: 353737330
--
f206ae0983e58c9904ed8b8f05f9caf564a446be by Matt Kulukundis <kfm@google.com>:
Import of CCTZ from GitHub.
PiperOrigin-RevId: 353682256
GitOrigin-RevId: c68f1886f5e8fd90eb0c2d2e68feaf00a7cdacda
Change-Id: I5790c1036c4f543c701d1039848fabf7ae881ad8
Diffstat (limited to 'absl/strings/internal/memutil.h')
0 files changed, 0 insertions, 0 deletions