llvm-6502/test
Hal Finkel 2c5f9584ba [PowerPC] Loop Data Prefetching for the BG/Q
The IBM BG/Q supercomputer's A2 cores have a hardware prefetching unit, the
L1P, but it does not prefetch directly into the A2's L1 cache. Instead, it
prefetches into its own L1P buffer, and the latency to access that buffer is
significantly higher than that to the L1 cache (although smaller than the
latency to the L2 cache). As a result, especially when multiple hardware
threads are not actively busy, explicitly prefetching data into the L1 cache is
advantageous.

I've been using this pass out-of-tree for data prefetching on the BG/Q for well
over a year, and it has worked quite well. It is enabled by default only for
the BG/Q, but can be enabled for other cores as well via a command-line option.

Eventually, we might want to add some TTI interfaces and move this into
Transforms/Scalar (there is nothing particularly target dependent about it,
although only machines like the BG/Q will benefit from its simplistic
strategy).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@229966 91177308-0d34-0410-b5e6-96231b3b80d8
2015-02-20 05:08:21 +00:00
..
Analysis [LoopAccesses] Add -analyze support 2015-02-19 19:15:19 +00:00
Assembler Bitcode: Stop assuming non-null fields 2015-02-20 03:17:58 +00:00
Bindings
Bitcode
BugPoint
CodeGen [PowerPC] Loop Data Prefetching for the BG/Q 2015-02-20 05:08:21 +00:00
DebugInfo DebugInfo: Match Name and DisplayName in testcase 2015-02-19 23:48:17 +00:00
ExecutionEngine
Feature
FileCheck
Instrumentation [sanitizer] fix a test broken by r229940 2015-02-20 02:12:25 +00:00
Integer
JitListener
Linker
LTO
MC MC: Allow multiple comma-separated expressions on the .uleb128 directive. 2015-02-19 20:24:04 +00:00
Object
Other
SymbolRewriter
TableGen
tools
Transforms [InstCombine] Remove unnecessary variable indexing into single-element arrays 2015-02-20 03:05:53 +00:00
Unit
Verifier
YAMLParser
.clang-format
CMakeLists.txt
lit.cfg
lit.site.cfg.in
Makefile
Makefile.tests
TestRunner.sh