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* [RISCV] Add machine function pass to merge base + offsetSameer AbuAsal2018-06-271-208/+0
| | | | | | | | | | | | | | | | | | | | | | | | Summary: In r333455 we added a peephole to fix the corner cases that result from separating base + offset lowering of global address.The peephole didn't handle some of the cases because it only has a basic block view instead of a function level view. This patch replaces that logic with a machine function pass. In addition to handling the original cases it handles uses of the global address across blocks in function and folding an offset from LW\SW instruction. This pass won't run for OptNone compilation, so there will be a negative impact overall vs the old approach at O0. Reviewers: asb, apazos, mgrang Reviewed By: asb Subscribers: MartinMosbeck, brucehoult, the_o, rogfer01, mgorny, rbar, johnrusso, simoncook, niosHD, kito-cheng, shiva0217, zzheng, llvm-commits, edward-jones Differential Revision: https://reviews.llvm.org/D47857 llvm-svn: 335786
* [RISCV] Add peepholes for Global Address lowering patternsSameer AbuAsal2018-05-291-0/+208
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Summary: Base and offset are always separated when a GlobalAddress node is lowered (rL332641) as an optimization to reduce instruction count. However, this optimization is not profitable if the Global Address ends up being used in only instruction. This patch adds peephole optimizations that merge an offset of an address calculation into the LUI %%hi and ADD %lo of the lowering sequence. The peephole handles three patterns: 1) ADDI (ADDI (LUI %hi(global)) %lo(global)), offset ---> ADDI (LUI %hi(global + offset)) %lo(global + offset). This generates: lui a0, hi (global + offset) add a0, a0, lo (global + offset) Instead of lui a0, hi (global) addi a0, hi (global) addi a0, offset This pattern is for cases when the offset is small enough to fit in the immediate filed of ADDI (less than 12 bits). 2) ADD ((ADDI (LUI %hi(global)) %lo(global)), (LUI hi_offset)) ---> offset = hi_offset << 12 ADDI (LUI %hi(global + offset)) %lo(global + offset) Which generates the ASM: lui a0, hi(global + offset) addi a0, lo(global + offset) Instead of: lui a0, hi(global) addi a0, lo(global) lui a1, (offset) add a0, a0, a1 This pattern is for cases when the offset doesn't fit in an immediate field of ADDI but the lower 12 bits are all zeros. 3) ADD ((ADDI (LUI %hi(global)) %lo(global)), (ADDI lo_offset, (LUI hi_offset))) ---> offset = global + offhi20<<12 + offlo12 ADDI (LUI %hi(global + offset)) %lo(global + offset) Which generates the ASM: lui a1, %hi(global + offset) addi a1, %lo(global + offset) Instead of: lui a0, hi(global) addi a0, lo(global) lui a1, (offhi20) addi a1, (offlo12) add a0, a0, a1 This pattern is for cases when the offset doesn't fit in an immediate field of ADDI and both the lower 1 bits and high 20 bits are non zero. Reviewers: asb Reviewed By: asb Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, apazos, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang llvm-svn: 333455
* Rename DEBUG macro to LLVM_DEBUG.Nicola Zaghen2018-05-141-13/+14
| | | | | | | | | | | | | | | | 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
* Fix a bunch of places where operator-> was used directly on the return from ↵Craig Topper2018-05-051-1/+1
| | | | | | | | | | dyn_cast. Inspired by r331508, I did a grep and found these. Mostly just change from dyn_cast to cast. Some cases also showed a dyn_cast result being converted to bool, so those I changed to isa. llvm-svn: 331577
* Revert "[RISCV] implement li pseudo instruction"Alex Bradbury2018-04-181-43/+22
| | | | | | | | | Reverts rL330224, while issues with the C extension and missed common subexpression elimination opportunities are addressed. Neither of these issues are visible in current RISC-V backend unit tests, which clearly need expanding. llvm-svn: 330281
* [RISCV] implement li pseudo instructionAlex Bradbury2018-04-171-22/+43
| | | | | | | | | | | | | | The implementation follows the MIPS backend and expands the pseudo instruction directly during asm parsing. As the result, only real MC instructions are emitted to the MCStreamer. Additionally, PseudoLI instructions are emitted during codegen. The actual expansion to real instructions is performed during MI to MC lowering and is similar to the expansion performed by the GNU Assembler. Differential Revision: https://reviews.llvm.org/D41949 Patch by Mario Werner. llvm-svn: 330224
* [RISCV] Codegen support for RV32D floating point load/store, fadd.d, calling ↵Alex Bradbury2018-04-121-1/+41
| | | | | | | | | | | | | | | | conv fadd.d is required in order to force floating point registers to be used in test code, as parameters are passed in integer registers in the soft float ABI. Much of this patch is concerned with support for passing f64 on RV32D with a soft-float ABI. Similar to Mips, introduce pseudoinstructions to build an f64 out of a pair of i32 and to split an f64 to a pair of i32. BUILD_PAIR and EXTRACT_ELEMENT can't be used, as a BITCAST to i64 would be necessary, but i64 is not a legal type. llvm-svn: 329871
* [RISCV] Peephole optimisation for load/store of global values or constant ↵Alex Bradbury2018-03-191-0/+95
| | | | | | | | | | | addresses (load (add base, off), 0) -> (load base, off) (store val, (add base, off)) -> (store val, base, off) This is similar to an equivalent peephole optimisation in PPCISelDAGToDAG. llvm-svn: 327831
* [SelectionDAGISel] Add a debug print before call to Select. Adjust where ↵Craig Topper2018-01-261-3/+0
| | | | | | | | | | | | blank lines are printed during isel process to make things more sensibly grouped. Previously some targets printed their own message at the start of Select to indicate what they were selecting. For the targets that didn't, it means there was no print of the root node before any custom handling in the target executed. So if the target did something custom and never called SelectNodeCommon, no print would be made. For the targets that did print a message in Select, if they didn't custom handle a node SelectNodeCommon would reprint the root node before walking the isel table. It seems better to just print the message before the call to Select so all targets behave the same. And then remove the root node printing from SelectNodeCommon and just leave a message that says we're starting the table search. There were also some oddities in blank line behavior. Usually due to a \n after a call to SelectionDAGNode::dump which already inserted a new line. llvm-svn: 323551
* [RISCV] Add basic support for inline asm constraintsAlex Bradbury2018-01-101-0/+19
| | | | llvm-svn: 322217
* [RISCV] Support lowering FrameIndexAlex Bradbury2017-12-111-0/+20
| | | | | | | | | | | | | | | | Introduces the AddrFI "addressing mode", which is necessary simply because it's not possible to write a pattern that directly matches a frameindex. Ensure callee-saved registers are accessed relative to the stackpointer. This is necessary as callee-saved register spills are performed before the frame pointer is set. Move HexagonDAGToDAGISel::isOrEquivalentToAdd to SelectionDAGISel, so we can make use of it in the RISC-V backend. Differential Revision: https://reviews.llvm.org/D39848 llvm-svn: 320353
* [RISCV][NFC] Clean up RISCVDAGToDAGISel::SelectAlex Bradbury2017-11-211-14/+9
| | | | | | | | | | As pointed out in post-commit review of r318738, `return ReplaceNode(..)` when both ReplaceNode and the current function return void is confusing. This patch moves to using a more obvious early return, and moves to just using an if to catch the one case we currently care about. A future patch that adds further custom instruction selection can introduce a switch. llvm-svn: 318757
* [RISCV] Use register X0 (ZERO) for constant 0Alex Bradbury2017-11-211-0/+30
| | | | | | | | | | | | The obvious approach of defining a pattern like the one below actually doesn't work: `def : Pat<(i32 0), (i32 X0)>;` As was noted when Lanai made this change (https://reviews.llvm.org/rL288215), attempting to handle the constant 0 in tablegen leads to assertions due to a physical register being used where a virtual register is expected. llvm-svn: 318738
* [RISCV] Initial codegen support for ALU operationsAlex Bradbury2017-10-191-0/+63
This adds the minimum necessary to support codegen for simple ALU operations on RV32. Prolog and epilog insertion, support for memory operations etc etc follow in future patches. Leave guessInstructionProperties=1 until https://reviews.llvm.org/D37065 is reviewed and lands. Differential Revision: https://reviews.llvm.org/D29933 llvm-svn: 316188
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