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* [PowerPC] Remove self-copies in pre-emit peepholeNemanja Ivanovic2018-10-091-0/+24
| | | | | | | | | | | | | | | | | | There are occasionally instances where AADB rewrites registers in such a way that a reg-reg copy becomes a self-copy. Such an instruction is obviously redundant and can be removed. This patch does precisely that. Note that this will not remove various nop's that we insert (which are themselves just self-copies). The reason those are left alone is that all of them have their own opcodes (that just encode to a self-copy). What prompted this patch is the fact that these self-copies sometimes end up using registers that make the instruction a priority-setting nop, thereby having a significant effect on performance. Differential revision: https://reviews.llvm.org/D52432 llvm-svn: 344036
* [PowerPC] optimize conditional branch on CRSET/CRUNSETHiroshi Inoue2018-09-261-0/+71
| | | | | | | | | | | | | | This patch adds a check to optimize conditional branch (BC and BCn) based on a constant set by CRSET or CRUNSET. Other optimizers, such as block placement, may generate such code and hence I do this at the very end of the optimization in pre-emit peephole pass. A conditional branch based on a constant is eliminated or converted into unconditional branch. Also CRSET/CRUNSET is eliminated if the condition code register is not used by instruction other than the branch to be optimized. Differential Revision: https://reviews.llvm.org/D52345 llvm-svn: 343100
* Rename DEBUG macro to LLVM_DEBUG.Nicola Zaghen2018-05-141-4/+4
| | | | | | | | | | | | | | | | The DEBUG() macro is very generic so it might clash with other projects. The renaming was done as follows: - git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g' - git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM - Manual change to APInt - Manually chage DOCS as regex doesn't match it. In the transition period the DEBUG() macro is still present and aliased to the LLVM_DEBUG() one. Differential Revision: https://reviews.llvm.org/D43624 llvm-svn: 332240
* [PowerPC] Fix for PR35688 - handle out-of-range values for r+r to r+i conversionNemanja Ivanovic2017-12-291-1/+1
| | | | | | | | | | | | | | | Revision 320791 introduced a pass that transforms reg+reg instructions to reg+imm if they're fed by "load immediate". However, it didn't handle out-of-range shifts correctly as reported in PR35688. This patch fixes that and therefore the PR. Furthermore, there was undefined behaviour in the patch where the RHS of an initialization expression was 32 bits and constant `1` was shifted left 32 bits. This was fixed by ensuring the RHS is 64 bits just like the LHS. Differential Revision: https://reviews.llvm.org/D41369 llvm-svn: 321551
* [PPC] Also disable the pre-emit version of reg+reg to reg+imm transformation.Benjamin Kramer2017-12-181-1/+1
| | | | | | This has the same issue as the early pass disabled in r321010. llvm-svn: 321013
* MachineFunction: Return reference from getFunction(); NFCMatthias Braun2017-12-151-1/+1
| | | | | | The Function can never be nullptr so we can return a reference. llvm-svn: 320884
* [PowerPC] Convert r+r instructions to r+i (pre and post RA)Nemanja Ivanovic2017-12-151-0/+95
This patch adds the necessary infrastructure to convert instructions that take two register operands to those that take a register and immediate if the necessary operand is produced by a load-immediate. Furthermore, it uses this infrastructure to perform such conversions twice - first at MachineSSA and then pre-emit. There are a number of reasons we may end up with opportunities for this transformation, including but not limited to: - X-Form instructions chosen since the exact offset isn't available at ISEL time - Atomic instructions with constant operands (we will add patterns for this in the future) - Tail duplication may duplicate code where one block contains this redundancy - When emitting compare-free code in PPCDAGToDAGISel, we don't handle constant comparands specially Furthermore, this patch moves the initialization of PPCMIPeepholePass so that it can be used for MIR tests. llvm-svn: 320791
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