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and add a TargetLowering hook for it to use to determine when this is legal (i.e. not in PIC mode, etc.) This allows instruction selection to emit folded constant offsets in more cases, such as the included testcase, eliminating the need for explicit arithmetic instructions. This eliminates the need for the C++ code in X86ISelDAGToDAG.cpp that attempted to achieve the same effect, but wasn't as effective. Also, fix handling of offsets in GlobalAddressSDNodes in several places, including changing GlobalAddressSDNode's offset from int to int64_t. The Mips, Alpha, Sparc, and CellSPU targets appear to be unaware of GlobalAddress offsets currently, so set the hook to false on those targets. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57748 91177308-0d34-0410-b5e6-96231b3b80d8
//===- README.txt - Notes for improving CellSPU-specific code gen ---------===//
This code was contributed by a team from the Computer Systems Research
Department in The Aerospace Corporation:
- Scott Michel (head bottle washer and much of the non-floating point
instructions)
- Mark Thomas (floating point instructions)
- Michael AuYeung (intrinsics)
- Chandler Carruth (LLVM expertise)
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NONINFRINGEMENT, OR
OTHERWISE. IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE FOR DAMAGES
OF ANY KIND OR NATURE WHETHER BASED IN CONTRACT, TORT, OR OTHERWISE ARISING
OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE INCLUDING, WITHOUT
LIMITATION, DAMAGES RESULTING FROM LOST OR CONTAMINATED DATA, LOST PROFITS OR
REVENUE, COMPUTER MALFUNCTION, OR FOR ANY SPECIAL, INCIDENTAL, CONSEQUENTIAL,
OR PUNITIVE DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES OR
SUCH DAMAGES ARE FORESEEABLE.
---------------------------------------------------------------------------
--WARNING--:
--WARNING--: The CellSPU work is work-in-progress and "alpha" quality code.
--WARNING--:
If you are brave enough to try this code or help to hack on it, be sure
to add 'spu' to configure's --enable-targets option, e.g.:
./configure <your_configure_flags_here> \
--enable-targets=x86,x86_64,powerpc,spu
---------------------------------------------------------------------------
TODO:
* Finish branch instructions, branch prediction
These instructions were started, but only insofar as to get llvm-gcc-4.2's
crtbegin.ll working (which doesn't.)
* Double floating point support
This was started. "What's missing?" to be filled in.
* Intrinsics
Lots of progress. "What's missing/incomplete?" to be filled in.
===-------------------------------------------------------------------------===