mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-10-24 21:42:54 +02:00
d972bf8fab
Summary: Before this change, AttributeLists stored a pair of index and AttributeSet. This is memory efficient if most arguments do not have attributes. However, it requires doing a search over the pairs to test an argument or function attribute. Profiling shows that this loop was 0.76% of the time in 'opt -O2' of sqlite3.c, because LLVM constantly tests values for nullability. This was worth about 2.5% of mid-level optimization cycles on the sqlite3 amalgamation. Here are the full perf results: https://reviews.llvm.org/P7995 Here are just the before and after cycle counts: ``` $ perf stat -r 5 ./opt_before -O2 sqlite3.bc -o /dev/null 13,274,181,184 cycles # 3.047 GHz ( +- 0.28% ) $ perf stat -r 5 ./opt_after -O2 sqlite3.bc -o /dev/null 12,906,927,263 cycles # 3.043 GHz ( +- 0.51% ) ``` This patch *does not* change the indices used to query attributes, as requested by reviewers. Tracking whether an index is usable for array indexing is a huge pain that affects many of the internal APIs, so it would be good to come back later and do a cleanup to remove this internal adjustment. Reviewers: pete, chandlerc Subscribers: javed.absar, llvm-commits Differential Revision: https://reviews.llvm.org/D32819 llvm-svn: 303654 |
||
---|---|---|
.. | ||
ADT | ||
Analysis | ||
AsmParser | ||
Bitcode | ||
CodeGen | ||
Config | ||
DebugInfo | ||
Demangle | ||
ExecutionEngine | ||
IR | ||
IRReader | ||
LineEditor | ||
Linker | ||
LTO | ||
MC | ||
Object | ||
ObjectYAML | ||
Option | ||
Passes | ||
ProfileData | ||
Support | ||
TableGen | ||
Target | ||
ToolDrivers/llvm-lib | ||
Transforms | ||
XRay | ||
CMakeLists.txt | ||
InitializePasses.h | ||
LinkAllIR.h | ||
LinkAllPasses.h | ||
module.modulemap | ||
module.modulemap.build | ||
Pass.h | ||
PassAnalysisSupport.h | ||
PassInfo.h | ||
PassRegistry.h | ||
PassSupport.h |