Alexei Starovoitov 49cdd6c3d1 [bpf] Avoid extra pointer arithmetic for stack access
For the program like below
struct key_t {
  int pid;
  char name[16];
};
extern void test1(char *);
int test() {
  struct key_t key = {};
  test1(key.name);
  return 0;
}
For key.name, the llc/bpf may generate the below code:
  R1 = R10  // R10 is the frame pointer
  R1 += -24 // framepointer adjustment
  R1 |= 4   // R1 is then used as the first parameter of test1
OR operation is not recognized by in-kernel verifier.

This patch introduces an intermediate FI_ri instruction and
generates the following code that can be properly verified:
  R1 = R10
  R1 += -20

Patch by Yonghong Song <yhs@plumgrid.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@249371 91177308-0d34-0410-b5e6-96231b3b80d8
2015-10-06 04:00:53 +00:00
2015-03-12 01:25:29 +00:00

Low Level Virtual Machine (LLVM)
================================

This directory and its subdirectories contain source code for LLVM,
a toolkit for the construction of highly optimized compilers,
optimizers, and runtime environments.

LLVM is open source software. You may freely distribute it under the terms of
the license agreement found in LICENSE.txt.

Please see the documentation provided in docs/ for further
assistance with LLVM, and in particular docs/GettingStarted.rst for getting
started with LLVM and docs/README.txt for an overview of LLVM's
documentation setup.

If you're writing a package for LLVM, see docs/Packaging.rst for our
suggestions.
Description
Mirror of official llvm git repository located at http://llvm.org/git/llvm. Updated every five minutes.
Readme 473 MiB
Languages
LLVM 46.9%
C++ 42.5%
Assembly 8.9%
C 0.6%
Python 0.4%
Other 0.5%