mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2025-01-31 20:51:52 +01:00
984a615c7c
Summary: It can be useful for tools to be able to retrieve the values of variables declared via STATISTIC() directly without having to emit them and parse them back. Use cases include: * Needing to report specific statistics to a test harness * Wanting to post-process statistics. For example, to produce a percentage of functions that were fully selected by GlobalISel Make this possible by adding llvm::GetStatistics() which returns an iterator_range that can be used to inspect the statistics that have been touched during execution. When statistics are disabled (NDEBUG and not LLVM_ENABLE_STATISTICS) this method will return an empty range. This patch doesn't address the effect of multiple compilations within the same process. In such situations, the statistics will be cumulative for all compilations up to the GetStatistics() call. Reviewers: qcolombet, rtereshin, aditya_nandakumar, bogner Reviewed By: rtereshin, bogner Subscribers: llvm-commits, mgorny Differential Revision: https://reviews.llvm.org/D43901 This re-commit fixes a missing include of <vector> which it seems clang didn't mind but G++ and MSVC objected to. It seems that, clang was ok with std::vector only being forward declared at the point of use since it was fully defined eventually but G++/MSVC both rejected it at the point of use. llvm-svn: 326738
Design Of lib/System
====================
The software in this directory is designed to completely shield LLVM from any
and all operating system specific functionality. It is not intended to be a
complete operating system wrapper (such as ACE), but only to provide the
functionality necessary to support LLVM.
The software located here, of necessity, has very specific and stringent design
rules. Violation of these rules means that cracks in the shield could form and
the primary goal of the library is defeated. By consistently using this library,
LLVM becomes more easily ported to new platforms since the only thing requiring
porting is this library.
Complete documentation for the library can be found in the file:
llvm/docs/SystemLibrary.html
or at this URL:
http://llvm.org/docs/SystemLibrary.html
While we recommend that you read the more detailed documentation, for the
impatient, here's a high level summary of the library's requirements.
1. No system header files are to be exposed through the interface.
2. Std C++ and Std C header files are okay to be exposed through the interface.
3. No exposed system-specific functions.
4. No exposed system-specific data.
5. Data in lib/System classes must use only simple C++ intrinsic types.
6. Errors are handled by returning "true" and setting an optional std::string
7. Library must not throw any exceptions, period.
8. Interface functions must not have throw() specifications.
9. No duplicate function impementations are permitted within an operating
system class.
To accomplish these requirements, the library has numerous design criteria that
must be satisfied. Here's a high level summary of the library's design criteria:
1. No unused functionality (only what LLVM needs)
2. High-Level Interfaces
3. Use Opaque Classes
4. Common Implementations
5. Multiple Implementations
6. Minimize Memory Allocation
7. No Virtual Methods