llvm-project/clang/include
Hal Finkel ce0697f475 Add -freroll-loops to enable loop rerolling
This adds -freroll-loops (and -fno-reroll-loops in the usual way) to enable
loop rerolling as part of the optimization pass manager. This transformation
can enable vectorization, reduce code size (or both).

Briefly, loop rerolling can transform a loop like this:

for (int i = 0; i < 3200; i += 5) {
  a[i]     += alpha * b[i];
  a[i + 1] += alpha * b[i + 1];
  a[i + 2] += alpha * b[i + 2];
  a[i + 3] += alpha * b[i + 3];
  a[i + 4] += alpha * b[i + 4];
}

into this:

for (int i = 0; i < 3200; ++i) {
  a[i] += alpha * b[i];
}

Loop rerolling is currently disabled by default at all optimization levels.

llvm-svn: 194967
2013-11-17 16:03:29 +00:00
..
clang Add -freroll-loops to enable loop rerolling 2013-11-17 16:03:29 +00:00
clang-c Fixes a typo and changes references to the function clang_displayDiagnostic (which was removed in r96823) to clang_formatDiagnostics. 2013-11-17 09:46:45 +00:00
CMakeLists.txt
Makefile