Commit Graph

351 Commits

Author SHA1 Message Date
Alex Bradbury 639df9e4c0 [RISCV] Compress addiw rd, x0, simm6 to c.li rd, simm6
A pattern was present for addi rd, x0, simm6 but not addiw which is
semantically identical when the source register is x0. This patch addresses
that, and the benefit can be seen in rv64c-aliases-valid.s.

llvm-svn: 343911
2018-10-06 06:09:46 +00:00
Ana Pazos 9d6c55323f [RISCV] Support named operands for CSR instructions.
Reviewers: asb, mgrang

Reviewed By: asb

Subscribers: jocewei, mgorny, jfb, PkmX, MartinMosbeck, brucehoult, the_o, rkruppe, rogfer01, rbar, johnrusso, simoncook, jordy.potman.lists, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones

Differential Revision: https://reviews.llvm.org/D46759

llvm-svn: 343822
2018-10-04 21:50:54 +00:00
Alex Bradbury 5bf3b20e99 [RISCV] Remove overzealous is64Bit checks
lowerGlobalAddress, lowerBlockAddress, and insertIndirectBranch contain 
overzealous checks for is64Bit. These functions are all safe as-implemented 
for RV64.

llvm-svn: 343781
2018-10-04 14:30:03 +00:00
Alex Bradbury e96b7c88a3 [RISCV] Bugfix for floats passed on the stack with the ILP32 ABI on RV32F
f32 values passed on the stack would previously cause an assertion in 
unpackFromMemLoc.. This would only trigger in the presence of the F extension 
making f32 a legal type. Otherwise the f32 would be legalized.

This patch fixes that by keeping LocVT=f32 when a float is passed on the 
stack. It also adds test coverage for this case, and tests that also 
demonstrate lw/sw/flw/fsw will be selected when most profitable. i.e. there is 
no unnecessary i32<->f32 conversion in registers.

llvm-svn: 343756
2018-10-04 07:28:49 +00:00
Alex Bradbury 0e16766b76 [RISCV][NFC] Fix naming of RISCVISelLowering::{LowerRETURNADDR,LowerFRAMEADDR}
Rename to lowerRETURNADDR, lowerFRAMEADDR in order to be consistent with the 
LLVM coding style and the other functions in this file.

llvm-svn: 343752
2018-10-04 05:27:50 +00:00
Alex Bradbury 5ac0a2fc48 [RISCV] Handle redundant SplitF64+BuildPairF64 pairs in a DAGCombine
r343712 performed this optimisation during instruction selection. As Eli 
Friedman pointed out in post-commit review, implementing this as a DAGCombine 
might allow opportunities for further optimisations.

llvm-svn: 343741
2018-10-03 23:30:16 +00:00
Alex Bradbury 1dbfdeb6e5 [RISCV][NFC] Refactor LocVT<->ValVT converstion in RISCVISelLowering
There was some duplicated logic for using the LocInfo of a CCValAssign in 
order to convert from the ValVT to LocVT or vice versa. Resolve this by 
factoring out convertLocVTFromValVT from unpackFromRegLoc. Also rename 
packIntoRegLoc to the more appropriate convertValVTToLocVT and call these 
helper functions consistently.

llvm-svn: 343737
2018-10-03 22:53:25 +00:00
Alex Bradbury ce9049952f [RISCV][NFCI] Handle redundant splitf64+buildpairf64 pairs during instruction selection
Although we can't write a tablegen pattern to remove redundant 
splitf64+buildf64 pairs due to the multiple return values, we can handle it 
with some C++ selection code. This is simpler than removing them after 
instruction selection through RISCVDAGToDAGISel::PostprocessISelDAG, as was 
done previously.

llvm-svn: 343712
2018-10-03 20:12:10 +00:00
Alex Bradbury d33ffe9bb1 [RISCV][NFC] Refactor RISCVDAGToDAGISel::Select
Introduce and use a switch on the opcode.

llvm-svn: 343688
2018-10-03 13:13:13 +00:00
Alex Bradbury d934032e48 [RISCV] Gate float<->int and double<->int conversion patterns on IsRV32
The patterns as defined are correct only when XLen==32.

This is another preparatory patch for a set of patches that flesh out RV64 
codegen.

llvm-svn: 343679
2018-10-03 11:35:22 +00:00
Alex Bradbury d464ed8c2e [RISCV] Remove XLenVT==i32 assumptions from RISCVInstrInfo td
1. brcond operates on an condition.
2. atomic_fence and the pseudo AMO instructions should all take xlen immediates 

This allows the same definitions and patterns to work for RV64 (XLenVT==i64).

llvm-svn: 343678
2018-10-03 11:14:26 +00:00
Alex Bradbury a9ac5994b1 [RISCV] Gate simm32 materialisation pattern and SW pattern on IsRV32
These patterns are not correct for RV64.

llvm-svn: 343677
2018-10-03 11:04:59 +00:00
Alex Bradbury 96ed75d066 [RISCV][MC] Modify evaluateConstantImm interface to allow reuse from addExpr
This is a trivial refactoring that I'm committing now as it makes a patch I'm 
about to post for review easier to follow. There is some overlap between 
evaluateConstantImm and addExpr in RISCVAsmParser. This patch allows 
evaluateConstantImm to be reused from addExpr to remove this overlap. The 
benefit will be greater when a future patch adds extra code to allows 
immediates to be evaluated from constant symbols (e.g. `.equ CONST, 0x1234`).

No functional change intended.

llvm-svn: 342641
2018-09-20 11:40:43 +00:00
Alex Bradbury 226f3ef5a5 [RISCV][MC] Improve parsing of jal/j operands
Examples such as `jal a3`, `j a3` and `jal a3, a3` are accepted by gas 
but rejected by LLVM MC. This patch rectifies this. I introduce 
RISCVAsmParser::parseJALOffset to ensure that symbol names that coincide with 
register names can safely be parsed. This is made a somewhat fiddly due to the 
single-operand alias form (see the comment in parseJALOffset for more info).

Differential Revision: https://reviews.llvm.org/D52029

llvm-svn: 342629
2018-09-20 08:10:35 +00:00
Alex Bradbury 21aea51e71 [RISCV] Codegen for i8, i16, and i32 atomicrmw with RV32A
Introduce a new RISCVExpandPseudoInsts pass to expand atomic 
pseudo-instructions after register allocation. This is necessary in order to 
ensure that register spills aren't introduced between LL and SC, thus breaking 
the forward progress guarantee for the operation. AArch64 does something 
similar for CmpXchg (though only at O0), and Mips is moving towards this 
approach (see D31287). See also [this mailing list 
post](http://lists.llvm.org/pipermail/llvm-dev/2016-May/099490.html) from 
James Knight, which summarises the issues with lowering to ll/sc in IR or 
pre-RA.

See the [accompanying RFC 
thread](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123993.html) for an 
overview of the lowering strategy.

Differential Revision: https://reviews.llvm.org/D47882

llvm-svn: 342534
2018-09-19 10:54:22 +00:00
Alex Bradbury 68f73c1206 [RISCV][MC] Use a custom ParserMethod for the bare_symbol operand type
This allows the hard-coded shouldForceImmediate logic to be removed because 
the generated MatchOperandParserImpl makes use of the current context (i.e. 
the current mnemonic) to determine parsing behaviour, and so won't first try 
to parse a register before parsing a symbol name.

No functional change is intended. gas accepts immediate arguments for call, 
tail and lla. This patch doesn't address this discrepancy.

Differential Revision: https://reviews.llvm.org/D51733

llvm-svn: 342488
2018-09-18 15:18:16 +00:00
Alex Bradbury 7d0e18d0dd [RISCV][MC] Reject bare symbols for the simm12 operand type
addi a0, a0, foo and lw a0, foo(a0) and similar are now rejected. An explicit 
%lo and %pcrel_lo modifier is required. This matches gas behaviour.

llvm-svn: 342487
2018-09-18 15:13:29 +00:00
Alex Bradbury 74340f1805 [RISCV][MC] Tighten up checking of sybol operands to lui and auipc
Reject bare symbols and accept only %pcrel_hi(sym) for auipc and %hi(sym) for 
lui. Also test valid operand modifiers in rv32i-valid.s.

Note this is slightly stricter than gas, which will accept either %pcrel_hi or 
%hi for both lui and auipc.

Differential Revision: https://reviews.llvm.org/D51731

llvm-svn: 342486
2018-09-18 15:08:35 +00:00
Ana Pazos 065b088759 [RISCV][MC] Reject bare symbols for the simm6 and simm6nonzero operand types
Summary:
Fixed assertions due to invalid fixup when encoding compressed instructions
 (c.addi, c.addiw, c.li, c.andi) with bare symbols with/without modifiers.
  This matches GAS behavior as well.

This bug was uncovered by a LLVM MC Disassembler Protocol Buffer Fuzzer
for the RISC-V assembly language.

Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, asb

Differential Revision: https://reviews.llvm.org/D52005

llvm-svn: 342160
2018-09-13 18:37:23 +00:00
Ana Pazos b0799dda77 [RISCV] Fix decoding of invalid instruction with C extension enabled.
Summary:
The illegal instruction 0x00 0x00 is being wrongly decoded as
c.addi4spn with 0 immediate.

The invalid instruction 0x01 0x61 is being wrongly decoded as
c.addi16sp with 0 immediate.

This bug was uncovered by a LLVM MC Disassembler Protocol Buffer Fuzzer
for the RISC-V assembly language.

Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, asb

Differential Revision: https://reviews.llvm.org/D51815

llvm-svn: 342159
2018-09-13 18:21:19 +00:00
Benjamin Kramer 27c769d28a [Target] Untangle disassemblers
Disassemblers cannot depend on main target headers. The same is true for
MCTargetDesc, but there's a lot more cleanup needed for that.

llvm-svn: 341822
2018-09-10 12:53:46 +00:00
Ana Pazos b2ed11a086 [RISCV] Fix crash in decoding instruction with unknown floating point rounding mode
Summary:
Instead of crashing in printFRMArg, decode and warn about invalid instruction.

This bug was uncovered by a LLVM MC Disassembler Protocol Buffer Fuzzer
for the RISC-V assembly language.

Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, asb

Differential Revision: https://reviews.llvm.org/D51705

llvm-svn: 341691
2018-09-07 18:43:43 +00:00
Ana Pazos b97d18945b [RISCV] Fix AddressSanitizer heap-buffer-overflow in disassembling
Summary:
RISCVDisassembler should check number of bytes available before reading them.
Crash noticed when enabling -DLLVM_USE_SANITIZER=Address.

This bug was uncovered by a LLVM MC Disassembler Protocol Buffer Fuzzer for the RISC-V assembly language.

Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, asb

Differential Revision: https://reviews.llvm.org/D51708

llvm-svn: 341686
2018-09-07 18:23:19 +00:00
Ana Pazos 6b34051b33 [RISCV] Fixed SmallVector.h Assertion `idx < size()'
Summary:

RISCVAsmParser needs to handle the case the error message is of specific type, other than the generic Match_InvalidOperand, and the corresponding
operand is missing.

This bug was uncovered by a LLVM MC Assembler Protocol Buffer Fuzzer  for the RISC-V assembly language.

Reviewers: asb

Reviewed By: asb

Subscribers: llvm-commits, jocewei, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX

Differential Revision: https://reviews.llvm.org/D50790

llvm-svn: 341104
2018-08-30 19:43:19 +00:00
Roger Ferrer Ibanez fe28217048 [RISCV] atomic_store_nn have a different layout to regular store
We cannot directy reuse the patterns of StPat because for some reason the store
DAG node and the atomic_store_nn DAG nodes put the ptr and the value in
different positions. Currently we attempt to store the address to an address
formed by the value.

Differential Revision: https://reviews.llvm.org/D51217

llvm-svn: 340722
2018-08-27 07:08:18 +00:00
Ana Pazos ecc65eddec [RISCV] Fixed Assertion`Kind == Immediate && "Invalid type access!"' failed.
Summary:
Missing check for isImm() in some Immediate classes.

This bug was uncovered by a LLVM MC Assembler Protocol Buffer Fuzzer
for the RISC-V assembly language.

Reviewers: hiraditya, asb

Reviewed By: hiraditya, asb

Subscribers: llvm-commits, hiraditya, kito-cheng, shiva0217, rkruppe, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei

Differential Revision: https://reviews.llvm.org/D50797

llvm-svn: 340674
2018-08-24 23:47:49 +00:00
Ana Pazos 61b28ede75 [RISCV] Fix std::advance slowness
Summary:
It seems std::advance template is treating "-MFI.getCalleeSavedInfo().size()"
as a large unsigned value", causing slowness.

Thanks to Henrik Gustafsson for reporting the issue.

Reviewers: asb

Reviewed By: asb

Subscribers: llvm-commits, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, MartinMosbeck, brucehoult, the_o, rkruppe, PkmX, jocewei, asb

Differential Revision: https://reviews.llvm.org/D51148

llvm-svn: 340669
2018-08-24 23:13:59 +00:00
Roger Ferrer Ibanez 734a04ea33 [RISCV] Remove unused function
This function is not virtual, it is private and it is not called anywhere. No
regression is introduced by removing it.

I think we can safely remove it.

Differential Revision: https://reviews.llvm.org/D50836

llvm-svn: 340024
2018-08-17 13:40:03 +00:00
Roger Ferrer Ibanez c8f4dbbc63 [RISCV] Fix incorrect use of MCInstBuilder
This is a fix for r339314.

MCInstBuilder uses the named parameter idiom and an 'operator MCInst&' to ease
the creation of MCInsts. As the object of MCInstBuilder owns the MCInst is
manipulating, the lifetime of the MCInst is bound to that of MCInstBuilder.

In r339314 I bound a reference to the MCInst in an initializer. The
temporary of MCInstBuilder (and also its MCInst) is destroyed at the end of
the declaration leading to a dangling reference.

Fix this by using MCInstBuilder inside an argument of a function call.
Temporaries in function calls are destroyed in the enclosing full expression,
so the the reference to MCInst is still valid when emitToStreamer executes.

llvm-svn: 339654
2018-08-14 08:30:42 +00:00
Chih-Mao Chen 5d94b25ffe Test commit: fix punctuation
llvm-svn: 339652
2018-08-14 08:08:39 +00:00
Ana Pazos 10de234905 [RISC-V] Fixed alias for addi x2, x2, 0
A missing check for non-zero immediate in MCOperandPredicate
caused c.addi16sp sp, 0 to be selected which is not a valid
instruction.

llvm-svn: 339381
2018-08-09 20:51:53 +00:00
Roger Ferrer Ibanez 577a97e2b9 [RISCV] Add "lla" pseudo-instruction to assembler
This pseudo-instruction is similar to la but uses PC-relative addressing
unconditionally. This is, la is only different to lla when using -fPIC. This
pseudo-instruction seems often forgotten in several specs but it is definitely
mentioned in binutils opcodes/riscv-opc.c. The semantics are defined both in
page 37 of the "RISC-V Reader" book but also in function macro found in
gas/config/tc-riscv.c.

This is a very first step towards adding PIC support for Linux in the RISC-V
backend.

The lla pseudo-instruction expands to a sequence of auipc + addi with a couple
of pc-rel relocations where the second points to the first one. This is
described in
https://github.com/riscv/riscv-elf-psabi-doc/blob/master/riscv-elf.md#pc-relative-symbol-addresses

For now, this patch only introduces support of that pseudo instruction at the
assembler parser.

Differential Revision: https://reviews.llvm.org/D49661

llvm-svn: 339314
2018-08-09 07:08:20 +00:00
Alex Bradbury 07224dfb47 [RISCV] Add mnemonic alias: move, sbreak and scall.
Further improve compatibility with the GNU assembler.

Differential Revision: https://reviews.llvm.org/D50217
Patch by Kito Cheng.

llvm-svn: 339255
2018-08-08 14:53:45 +00:00
Alex Bradbury 7d8d87c143 [RISCV] Add InstAlias definitions for add[w], and, xor, or, sll[w], srl[w], sra[w], slt and sltu with immediate
Match the GNU assembler in supporting immediate operands for these 
instructions even when the reg-reg mnemonic is used.

Differential Revision: https://reviews.llvm.org/D50046
Patch by Kito Cheng.

llvm-svn: 339252
2018-08-08 14:45:44 +00:00
Kito Cheng dffce953bf Test commit.
llvm-svn: 338672
2018-08-02 05:38:18 +00:00
Ana Pazos 2e4106b73d [RISCV] Add support for _interrupt attribute
- Save/restore only registers that are used.
This includes Callee saved registers and Caller saved registers
(arguments and temporaries) for integer and FP registers.
- If there is a call in the interrupt handler, save/restore all
Caller saved registers (arguments and temporaries) and all FP registers.
- Emit special return instructions depending on "interrupt"
attribute type.
Based on initial patch by Zhaoshi Zheng.

Reviewers: asb

Reviewed By: asb

Subscribers: rkruppe, the_o, MartinMosbeck, brucehoult, rbar, johnrusso, simoncook, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, rogfer01, llvm-commits

Differential Revision: https://reviews.llvm.org/D48411

llvm-svn: 338047
2018-07-26 17:49:43 +00:00
Sameer AbuAsal 9b65ffb097 [RISCV] Add machine function pass to merge base + offset
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
2018-06-27 20:51:42 +00:00
Sameer AbuAsal e01e711c64 [RISCV] Tail calls don't need to save return address
Summary:
 When expanding the PseudoTail in expandFunctionCall() we were using X6
 to save the return address. Since this is a tail call the return
 address is not needed, this patch replaces it with X0 to be ignored.

 This matches the behaviour listed in the ISA V2.2 document page 110.
 tail offset -----> jalr x0, x6, offset

 GCC exhibits the same behavior.

Reviewers: apazos, asb, mgrang

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, rogfer01

Differential Revision: https://reviews.llvm.org/D48343

llvm-svn: 335239
2018-06-21 14:37:09 +00:00
Alex Bradbury fafdebcfcb [RISCV] Accept fmv.s.x and fmv.x.s as mnemonic aliases for fmv.w.x and fmv.x.w
These instructions were renamed in version 2.2 of the user-level ISA spec, but 
the old name should also be accepted by standard tools.

llvm-svn: 335154
2018-06-20 18:42:25 +00:00
Alex Bradbury 79d2b50ca8 [RISCV] Add InstAlias definitions for fgt.{s|d}, fge.{s|d}
These are produced by GCC and supported by GAS, but not currently contained in 
the pseudoinstruction listing in the RISC-V ISA manual.

llvm-svn: 335127
2018-06-20 14:03:02 +00:00
Alex Bradbury 18b9bd7d6c [RISCV] Add InstAlias definitions for sgt and sgtu
These are produced by GCC and supported by GAS, but not currently contained in 
the pseudoinstruction listing in the RISC-V ISA manual.

llvm-svn: 335120
2018-06-20 12:54:02 +00:00
Alex Bradbury 96f492d7df [RISCV] Add codegen support for atomic load/stores with RV32A
Fences are inserted according to table A.6 in the current draft of version 2.3
of the RISC-V Instruction Set Manual, which incorporates the memory model
changes and definitions contributed by the RISC-V Memory Consistency Model
task group.

Instruction selection failures will now occur for 8/16/32-bit atomicrmw and 
cmpxchg operations when targeting RV32IA until lowering for these operations 
is added in a follow-on patch.

Differential Revision: https://reviews.llvm.org/D47589

llvm-svn: 334591
2018-06-13 12:04:51 +00:00
Alex Bradbury dc790dd5d0 [RISCV] Codegen support for atomic operations on RV32I
This patch adds lowering for atomic fences and relies on AtomicExpandPass to
lower atomic loads/stores, atomic rmw, and cmpxchg to __atomic_* libcalls.

test/CodeGen/RISCV/atomic-* are modelled on the exhaustive
test/CodeGen/PPC/atomics-regression.ll, and will prove more useful once RV32A
codegen support is introduced.

Fence mappings are taken from table A.6 in the current draft of version 2.3 of
the RISC-V Instruction Set Manual, which incorporates the memory model changes
and definitions contributed by the RISC-V Memory Consistency Model task group.

Differential Revision: https://reviews.llvm.org/D47587

llvm-svn: 334590
2018-06-13 11:58:46 +00:00
Alex Bradbury ed53ca73ec [RISCV] Implement MC layer support for the fence.tso instruction
The instruction makes use of a previously ignored field in the fence
instruction. It is introduced in the version 2.3 draft of the RISC-V
specification after much work by the Memory Model Task Group.

As clarified here <https://github.com/riscv/riscv-isa-manual/issues/186>,
the fence.tso assembler mnemonic does not have operands.

llvm-svn: 334278
2018-06-08 10:39:05 +00:00
Alex Bradbury 6a4b5441e4 [RISCV] AsmParser support for the li pseudo instruction
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. The actual expansion to real instructions is 
similar to the expansion performed by the GNU Assembler.

This patch supersedes D41949.

Differential Revision: https://reviews.llvm.org/D46118
Patch by Mario Werner.

llvm-svn: 334203
2018-06-07 15:35:47 +00:00
Ilya Biryukov 3c9c10649b Fix compilation of WebAssembly and RISCV after r334078
llvm-svn: 334085
2018-06-06 10:57:50 +00:00
Amaury Sechet 8467411dad Set ADDE/ADDC/SUBE/SUBC to expand by default
Summary:
They've been deprecated in favor of UADDO/ADDCARRY or USUBO/SUBCARRY for a while.

Target that uses these opcodes are changed in order to ensure their behavior doesn't change.

Reviewers: efriedma, craig.topper, dblaikie, bkramer

Subscribers: jholewinski, arsenm, jyknight, sdardis, nemanjai, nhaehnle, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, jrtc27, zzheng, edward-jones, mgrang, atanasyan, llvm-commits

Differential Revision: https://reviews.llvm.org/D47422

llvm-svn: 333748
2018-06-01 13:21:33 +00:00
Shiva Chen c3d0e89284 [RISCV] Support resolving fixup_riscv_call and add to MCFixupKindInfo table
Resolving fixup_riscv_call by assembler when the linker relaxation diabled
and the function and callsite within the same compile unit.

And also adding static_assert after Infos array declaration
to avoid missing any new fixup in MCFixupKindInfo in the future.

Differential Revision: https://reviews.llvm.org/D47126

llvm-svn: 333487
2018-05-30 01:16:36 +00:00
Sameer AbuAsal 97684419e8 [RISCV] Add peepholes for Global Address lowering patterns
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
2018-05-29 19:34:54 +00:00
Shiva Chen 43bfe84451 [RISCV] Support linker relax function call from auipc and jalr to jal
To do this:
1. Add fixup_riscv_relax fixup types which eventually will
   transfer to R_RISCV_RELAX relocation types.

2. Insert R_RISCV_RELAX relocation types to auipc function call
   expression when linker relaxation enabled.

Differential Revision: https://reviews.llvm.org/D44886

llvm-svn: 333158
2018-05-24 06:21:23 +00:00
Mandeep Singh Grang ddcb95664e [RISCV] Lower the tail pseudoinstruction
This patch lowers the tail pseudoinstruction. This has been modeled after ARM's
tail call opt.

llvm-svn: 333137
2018-05-23 22:44:08 +00:00
Sameer AbuAsal eadce02741 [RISCV] Set CostPerUse for registers
Summary:
 Set CostPerUse higher for registers that are not used in the compressed
 instruction set. This will influence the greedy register allocator to reduce
 the use of registers that can't be encoded in 16 bit instructions. This
 affects register allocation even when compressed instruction isn't targeted,
 we see no major negative codegen impact.

Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, apazos, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang

Differential Revision: https://reviews.llvm.org/D47039

llvm-svn: 333132
2018-05-23 21:34:30 +00:00
Alex Bradbury 257d5b5639 [RISCV] Add symbol diff relocation support for RISC-V
For RISC-V it is desirable to have relaxation happen in the linker once 
addresses are known, and as such the size between two instructions/byte 
sequences in a section could change.

For most assembler expressions, this is fine, as the absolute address results 
in the expression being converted to a fixup, and finally relocations. 
However, for expressions such as .quad .L2-.L1, the assembler folds this down 
to a constant once fragments are laid out, under the assumption that the 
difference can no longer change, although in the case of linker relaxation the 
differences can change at link time, so the constant is incorrect. One place 
where this commonly appears is in debug information, where the size of a 
function expression is in a form similar to the above.

This patch extends the assembler to allow an AsmBackend to declare that it 
does not want the assembler to fold down this expression, and instead generate 
a pair of relocations that allow the linker to carry out the calculation. In 
this case, the expression is not folded, but when it comes to emitting a 
fixup, the generic FK_Data_* fixups are converted into a pair, one for the 
addition half, one for the subtraction, and this is passed to the relocation 
generating methods as usual. I have named these FK_Data_Add_* and 
FK_Data_Sub_* to indicate which half these are for.

For RISC-V, which supports this via e.g. the R_RISCV_ADD64, R_RISCV_SUB64 pair 
of relocations, these are also set to always emit relocations relative to 
local symbols rather than section offsets. This is to deal with the fact that 
if relocations were calculated on e.g. .text+8 and .text+4, the result 12 
would be stored rather than 4 as both addends are added in the linker.

Differential Revision: https://reviews.llvm.org/D45181
Patch by Simon Cook.

llvm-svn: 333079
2018-05-23 12:36:18 +00:00
Alex Bradbury 1c010d0fa4 [RISCV] Correctly report sizes for builtin fixups
This is a different approach to fixing the problem described in D46746. 
RISCVAsmBackend currently depends on the getSize helper function returning the 
number of bytes a fixup may change (note: some other backends have a similar 
helper named getFixupNumKindBytes). As noted in that review, this doesn't 
return the correct size for FK_Data_1, FK_Data_2, or FK_Data_8 meaning that 
too few bytes will be written in the case of FK_Data_8, and there's the 
potential of writing outside the Data array for the smaller fixups.

D46746 extends getSize to recognise some of the builtin fixup types. Rather 
than having a function that needs to be kept up to date as new builtin or 
target-specific fixups are added, We can calculate an appropriate bound on the 
number of bytes that might be touched using Info.TargetSize and 
Info.TargetOffset.

Differential Revision: https://reviews.llvm.org/D46965

llvm-svn: 333076
2018-05-23 10:53:56 +00:00
Peter Collingbourne dcd7d6c331 MC: Separate creating a generic object writer from creating a target object writer. NFCI.
With this we gain a little flexibility in how the generic object
writer is created.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47045

llvm-svn: 332868
2018-05-21 19:20:29 +00:00
Peter Collingbourne 571a3301ae MC: Change MCAsmBackend::writeNopData() to take a raw_ostream instead of an MCObjectWriter. NFCI.
To make this work I needed to add an endianness field to MCAsmBackend
so that writeNopData() implementations know which endianness to use.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47035

llvm-svn: 332857
2018-05-21 17:57:19 +00:00
Peter Collingbourne e3f652973e Support: Simplify endian stream interface. NFCI.
Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47032

llvm-svn: 332757
2018-05-18 19:46:24 +00:00
Shiva Chen 6e07dfb148 [RISCV] Add WasForced parameter to MCAsmBackend::fixupNeedsRelaxationAdvanced
For RISCV branch instructions, we need to preserve relocation types when linker
relaxation enabled, so then linker could modify offset when the branch offsets
changed.

We preserve relocation types by define shouldForceRelocation.
IsResolved return by evaluateFixup will always false when shouldForceRelocation
return true. It will make RISCV MC Branch Relaxation always relax 16-bit
branches to 32-bit form, even if the symbol actually could be resolved.

To avoid 16-bit branches always relax to 32-bit form when linker relaxation
enabled, we add a new parameter WasForced to indicate that the symbol actually
couldn't be resolved and not forced by shouldForceRelocation return true.

RISCVAsmBackend::fixupNeedsRelaxationAdvanced could relax branches with
unresolved symbols by (!IsResolved && !WasForced).

RISCV MC Branch Relaxation is needed because RISCV could perform 32-bit
to 16-bit transformation in MC layer.

Differential Revision: https://reviews.llvm.org/D46350

llvm-svn: 332696
2018-05-18 06:42:21 +00:00
Sameer AbuAsal 1dc0a8fb18 [RISCV] Separate base from offset in lowerGlobalAddress
Summary:
When lowering global address, lower the base as a TargetGlobal first then
 create an SDNode for the offset separately and chain it to the address calculation

 This optimization will create a DAG where the base address of a global access will
 be reused between different access. The offset can later be folded into the immediate
 part of the memory access instruction.

  With this optimization we generate:

    lui a0, %hi(s)
    addi a0, a0, %lo(s) ; shared base address.

    addi a1, zero, 20 ; 2 instructions per access.
    sw a1, 44(a0)

    addi a1, zero, 10
    sw a1, 8(a0)

    addi a1, zero, 30
    sw a1, 80(a0)

    Instead of:

    lui a0, %hi(s+44) ; 3 instructions per access.
    addi a1, zero, 20
    sw a1, %lo(s+44)(a0)

    lui a0, %hi(s+8)
    addi a1, zero, 10
    sw a1, %lo(s+8)(a0)

    lui a0, %hi(s+80)
    addi a1, zero, 30
    sw a1, %lo(s+80)(a0)

    Which will save one instruction per access.

Reviewers: asb, apazos

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, mgrang, apazos, asb, llvm-commits

Differential Revision: https://reviews.llvm.org/D46989

llvm-svn: 332641
2018-05-17 18:14:53 +00:00
Mandeep Singh Grang ef0ebf2806 [RISCV] Implement MC layer support for the tail pseudoinstruction
Summary:
This patch implements MC support for tail psuedo instruction.
A follow-up patch implements the codegen support as well as handling of the indirect tail pseudo instruction.

Reviewers: asb, apazos

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, edward-jones, llvm-commits

Differential Revision: https://reviews.llvm.org/D46221

llvm-svn: 332634
2018-05-17 17:31:27 +00:00
Alex Bradbury 6a53023b4e [RISCV] Set isReMaterializable on ADDI and LUI instructions
The isReMaterlizable flag is somewhat confusing, unlike most other instruction 
flags it is currently interpreted as a hint (mightBeRematerializable would be 
a better name). While LUI is always rematerialisable, for an instruction like 
ADDI it depends on its operands. TargetInstrInfo::isTriviallyReMaterializable 
will call TargetInstrInfo::isReallyTriviallyReMaterializable, which in turn 
calls TargetInstrInfo::isReallyTriviallyReMaterializableGeneric. We rely on 
the logic in the latter to pick out instances of ADDI that really are 
rematerializable.

The isReMaterializable flag does make a difference on a variety of test 
programs. The recently committed remat.ll test case demonstrates how stack 
usage is reduce and a unnecessary lw/sw can be removed. Stack usage in the 
Proc0 function in dhrystone reduces from 192 bytes to 112 bytes.

For the sake of completeness, this patch also implements 
RISCVRegisterInfo::isConstantPhysReg. Although this is called from a number of 
places, it doesn't seem to result in different codegen for any programs I've 
thrown at it. However, it is called in the rematerialisation codepath and it 
seems sensible to implement something correct here.

Differential Revision: https://reviews.llvm.org/D46182

llvm-svn: 332617
2018-05-17 15:51:37 +00:00
Alex Bradbury cea6db0480 [RISCV] Add support for .half, .hword, .word, .dword directives
These directives are recognised by gas. Support is added through the use of 
addAliasForDirective.

Also match RISC-V gcc in preferring .half and .word for 16-bit and 32-bit data 
directives.

llvm-svn: 332574
2018-05-17 05:58:08 +00:00
Shiva Chen 3969425081 [RISCV] Define FeatureRelax and shouldForceRelocation for RISCV linker relaxation
1. Deine FeatureRelax to enable/disable linker relaxation.

2. Define shouldForceRelocation to preserve relocation types even if the fixup
   can be resolved when linker relaxation enabled. This is necessary for
   correctness as offsets may change during relaxation.

Differential Revision: https://reviews.llvm.org/D46674

llvm-svn: 332318
2018-05-15 01:28:50 +00:00
Nicola Zaghen d34e60ca85 Rename DEBUG macro to LLVM_DEBUG.
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
2018-05-14 12:53:11 +00:00
Alex Bradbury bca0c3cdb6 [RISCV] Support .option rvc and norvc assembler directives
These directives allow the 'C' (compressed) extension to be enabled/disabled 
within a single file.

Differential Revision: https://reviews.llvm.org/D45864
Patch by Kito Cheng

llvm-svn: 332107
2018-05-11 17:30:28 +00:00
Craig Topper 781aa181ab Fix a bunch of places where operator-> was used directly on the return from 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
2018-05-05 01:57:00 +00:00
Alex Bradbury fda6037e98 [RISCV] Implement isLoadFromStackSlot and isStoreToStackSlot
This causes some slight shuffling but no meaningful codegen differences on the 
corpus I used for testing, but it has a larger impact when combined with e.g. 
rematerialisation. Regardless, it makes sense to report as accurate 
target-specific information as possible.

llvm-svn: 330949
2018-04-26 15:34:27 +00:00
Alex Bradbury 15e894baee [RISCV] Implement isZextFree
This returns true for 8-bit and 16-bit loads, allowing LBU/LHU to be selected
and avoiding unnecessary masks.

llvm-svn: 330943
2018-04-26 14:04:18 +00:00
Alex Bradbury 130b8b3f2b [RISCV] Implement isTruncateFree
Adapted from ARM's implementation introduced in r313533 and r314280.

llvm-svn: 330940
2018-04-26 13:37:00 +00:00
Alex Bradbury dcbff63c24 [RISCV] Implement isLegalICmpImmediate
I'm unable to construct a representative test case that demonstrates the 
advantage, but it seems sensible to report accurate target-specific 
information regardless.

llvm-svn: 330938
2018-04-26 13:15:17 +00:00
Alex Bradbury 5c41ecedf8 [RISCV] Implement isLegalAddImmediate
This causes a trivial improvement in the recently added lsr-legaladdimm.ll 
test case.

llvm-svn: 330937
2018-04-26 13:00:37 +00:00
Alex Bradbury 09926296df [RISCV] Implement isLegalAddressingMode for RISC-V
This has no impact on codegen for the current RISC-V unit tests or my small 
benchmark set and very minor changes in a few programs in the GCC torture 
suite. Based on this, I haven't been able to produce a representative test 
program that demonstrates a benefit from isLegalAddressingMode. I'm committing 
the patch anyway, on the basis that presenting accurate information to the 
target-independent code is preferable to relying on incorrect generic 
assumptions.

llvm-svn: 330932
2018-04-26 12:13:48 +00:00
Alex Bradbury cd8688a4c2 [RISCV] Allow call pseudoinstruction to be used to call a function name that coincides with a register name
Previously `call zero`, `call f0` etc would fail. This leads to compilation 
failures if building programs that define functions with those names and using 
-save-temps.

llvm-svn: 330846
2018-04-25 17:25:29 +00:00
Shiva Chen d58bd8dc4a [RISCV] Expand function call to "call" pseudoinstruction
To do this:
1. Change GlobalAddress SDNode to TargetGlobalAddress to avoid legalizer
   split the symbol.

2. Change ExternalSymbol SDNode to TargetExternalSymbol to avoid legalizer
   split the symbol.

3. Let PseudoCALL match direct call with target operand TargetGlobalAddress
   and TargetExternalSymbol.

Differential Revision: https://reviews.llvm.org/D44885

llvm-svn: 330827
2018-04-25 14:19:12 +00:00
Shiva Chen 98f9389f65 [RISCV] Support "call" pseudoinstruction in the MC layer
To do this:
1. Add PseudoCALLIndirct to match indirect function call.

2. Add PseudoCALL to support parsing and print pseudo `call` in assembly

3. Expand PseudoCALL to the following form with R_RISCV_CALL relocation type
   while encoding:
        auipc ra, func
        jalr ra, ra, 0

If we expand PseudoCALL before emitting assembly, we will see auipc and jalr
pair when compile with -S. It's hard for assembly parser to parsing this
pair and identify it's semantic is function call and then insert R_RISCV_CALL
relocation type. Although we could insert R_RISCV_PCREL_HI20 and
R_RISCV_PCREL_LO12_I relocation types instead of R_RISCV_CALL.
Due to RISCV relocation design, auipc and jalr pair only can relax to jal with
R_RISCV_CALL + R_RISCV_RELAX relocation types.

We expand PseudoCALL as late as encoding(RISCVMCCodeEmitter) instead of before
emitting assembly(RISCVAsmPrinter) because we want to preserve call
pseudoinstruction in assembly code. It's more readable and assembly parser
could identify call assembly and insert R_RISCV_CALL relocation type.

Differential Revision: https://reviews.llvm.org/D45859

llvm-svn: 330826
2018-04-25 14:18:55 +00:00
Alex Bradbury 3ff2022bb9 [RISCV] Introduce pattern for materialising immediates with 0 for lower 12 bits
These immediates can be materialised with just an lui, rather than an lui+addi 
pair.

llvm-svn: 330293
2018-04-18 20:34:23 +00:00
Alex Bradbury 099c720426 Revert "[RISCV] implement li pseudo instruction"
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
2018-04-18 19:02:31 +00:00
Alex Bradbury 480b7bc906 [RISCV] implement li pseudo instruction
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
2018-04-17 21:56:40 +00:00
Mandeep Singh Grang 88a8b269b4 [RISCV] Fix assert message operator
Summary:
Specifying assert message with an || operator makes the compiler interpret it
 as a bool. Changed it to &&.

Reviewers: asb, apazos

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, sabuasal, niosHD, kito-cheng, shiva0217, zzheng, llvm-commits

Differential Revision: https://reviews.llvm.org/D45660

llvm-svn: 330148
2018-04-16 18:56:10 +00:00
Sameer AbuAsal e8b7ff30e2 [RISCV] Add c.mv rs1, rs2 pattern for addi rs1, rs2, 0
Summary:
GCC compresses the pseudo instruction "mv rd, rs",  which is an alias of
"addi rd, rs, 0", to "c.mv rd, rs".

In LLVM we rely on the canonical MC instruction (MCInst) to do our compression
checks and since there is no rule to compress "addi rd, rs, 0" --> "c.mv
rd, rs" we lose this compression opportunity to gcc.

 In this patch we fix that by adding an addi to c.mv compression pattern, the
 instruction "mv rd, rs" will be compressed to "c.mv rd, rs" just like
 gcc does.

Patch by Zhaoshi Zheng (zzheng) and Sameer (sabuasal).

Reviewers: asb, apazos, zzheng, mgrang, shiva0217

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, niosHD, kito-cheng, llvm-commits

Differential Revision: https://reviews.llvm.org/D45583

llvm-svn: 329939
2018-04-12 19:22:40 +00:00
Shiva Chen b48b027d05 [RISCV] Change function alignment to 4 bytes, and 2 bytes for RVC
Summary:

According RISC-V ELF psABI specification, base RV32 and RV64 ISAs only
allow 32-bit instruction alignment, but instruction allow to be aligned
to 16-bit boundaries for C-extension.

So we just align to 4 bytes and 2 bytes for C-extension is enough.

Reviewers: asb, apazos

Differential Revision: https://reviews.llvm.org/D45560

Patch by Kito Cheng.

llvm-svn: 329899
2018-04-12 11:30:59 +00:00
Alex Bradbury 21d28fe8b8 [RISCV] Codegen support for RV32D floating point comparison operations
Also add double-prevoius-failure.ll which captures a test case that at one
point triggered a compiler crash, while developing calling convention support
for f64 on RV32D with soft-float ABI.

llvm-svn: 329877
2018-04-12 05:50:06 +00:00
Alex Bradbury 60baa2e015 [RISCV] Codegen support for RV32D floating point conversion operations
This also includes support and a test for truncating stores, which are now
possible thanks to the fpround pattern.

llvm-svn: 329876
2018-04-12 05:47:15 +00:00
Alex Bradbury 5d0dfa5e0e [RISCV] Add codegen support for RV32D floating point arithmetic operations
llvm-svn: 329874
2018-04-12 05:42:42 +00:00
Alex Bradbury 0b4175f160 [RISCV] Codegen support for RV32D floating point load/store, fadd.d, calling 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
2018-04-12 05:34:25 +00:00
Hiroshi Inoue 9ff2380ea6 [NFC] fix trivial typos in comments and error message
"is is" -> "is", "are are" -> "are"

llvm-svn: 329546
2018-04-09 04:37:53 +00:00
Sameer AbuAsal c1b0e66b58 [RISCV] Tablegen-driven Instruction Compression.
Summary:

    This patch implements a tablegen-driven Instruction Compression
    mechanism for generating RISCV compressed instructions
    (C Extension) from the expanded instruction form.

    This tablegen backend processes CompressPat declarations in a
    td file and generates all the compile-time and runtime checks
    required to validate the declarations, validate the input
    operands and generate correct instructions.

    The checks include validating register operands, immediate
    operands, fixed register operands and fixed immediate operands.

    Example:
      class CompressPat<dag input, dag output> {
        dag Input  = input;
        dag Output    = output;
        list<Predicate> Predicates = [];
      }

      let Predicates = [HasStdExtC] in {
      def : CompressPat<(ADD GPRNoX0:$rs1, GPRNoX0:$rs1, GPRNoX0:$rs2),
                        (C_ADD GPRNoX0:$rs1, GPRNoX0:$rs2)>;
      }

    The result is an auto-generated header file
    'RISCVGenCompressEmitter.inc' which exports two functions for
    compressing/uncompressing MCInst instructions, plus
    some helper functions:

      bool compressInst(MCInst& OutInst, const MCInst &MI,
                        const MCSubtargetInfo &STI,
                        MCContext &Context);

      bool uncompressInst(MCInst& OutInst, const MCInst &MI,
                          const MCRegisterInfo &MRI,
                          const MCSubtargetInfo &STI);

    The clients that include this auto-generated header file and
    invoke these functions can compress an instruction before emitting
    it, in the target-specific ASM or ELF streamer, or can uncompress
    an instruction before printing it, when the expanded instruction
    format aliases is favored.

    The following clients were added to implement compression\uncompression
    for RISCV:

    1) RISCVAsmParser::MatchAndEmitInstruction:
       Inserted a call to compressInst() to compresses instructions
       parsed by llvm-mc coming from an ASM input.
    2) RISCVAsmPrinter::EmitInstruction:
       Inserted a call to compressInst() to compress instructions that
       were lowered from Machine Instructions (MachineInstr).
    3) RVInstPrinter::printInst:
       Inserted a call to uncompressInst() to print the expanded
       version of the instruction instead of the compressed one (e.g,
       add s0, s0, a5 instead of c.add s0, a5) when -riscv-no-aliases
       is not passed.

This patch squashes D45119, D42780 and D41932. It was reviewed in  smaller patches by
asb, efriedma, apazos and mgrang.

Reviewers: asb, efriedma, apazos, llvm-commits, sabuasal

Reviewed By: sabuasal

Subscribers: mgorny, eraman, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, niosHD, kito-cheng, shiva0217, zzheng

Differential Revision: https://reviews.llvm.org/D45385

llvm-svn: 329455
2018-04-06 21:07:05 +00:00
Nico Weber 1cbd096914 Sort targetgen calls in lib/Target/*/CMakeLists.
Makes it easier to see mistakes such as the one fixed in r329178 and makes
the different target CMakeLists more consistent.

Also remove some stale-looking comments from the Nios2 target cmakefile.

No intended behavior change.

llvm-svn: 329181
2018-04-04 12:37:44 +00:00
Craig Topper 2fa1436206 [IR][CodeGen] Remove dependency on EVT from IR/Function.cpp. Move EVT to CodeGen layer.
Currently EVT is in the IR layer only because of Function.cpp needing a very small piece of the functionality of EVT::getEVTString(). The rest of EVT is used in codegen making CodeGen a better place for it.

The previous code converted a Type* to EVT and then called getEVTString. This was only expected to handle the primitive types from Type*. Since there only a few primitive types, we can just print them as strings directly.

Differential Revision: https://reviews.llvm.org/D45017

llvm-svn: 328806
2018-03-29 17:21:10 +00:00
Mandeep Singh Grang 98bc25a0f2 [RISCV] Use init_array instead of ctors for RISCV target, by default
Summary:
LLVM defaults to the newer .init_array/.fini_array scheme for static
constructors rather than the less desirable .ctors/.dtors (the UseCtors
flag defaults to false). This wasn't being respected in the RISC-V
backend because it fails to call TargetLoweringObjectFileELF::InitializeELF with the the appropriate
flag for UseInitArray.
This patch fixes this by implementing RISCVELFTargetObjectFile and overriding its Initialize method to call
InitializeELF(TM.Options.UseInitArray).

Reviewers: asb, apazos

Reviewed By: asb

Subscribers: mgorny, rbar, johnrusso, simoncook, jordy.potman.lists, sabuasal, niosHD, kito-cheng, shiva0217, llvm-commits

Differential Revision: https://reviews.llvm.org/D44750

llvm-svn: 328433
2018-03-24 18:37:19 +00:00
David Blaikie 36a0f226b1 Fix layering by moving ValueTypes.h from CodeGen to IR
ValueTypes.h is implemented in IR already.

llvm-svn: 328397
2018-03-23 23:58:31 +00:00
Alex Bradbury 65d6ea5e68 [RISCV] Codegen support for RV32F floating point comparison operations
This patch also includes extensive tests targeted at select and br+fcmp IR
inputs. A sequence of br+fcmp required support for FPR32 registers to be added
to RISCVInstrInfo::storeRegToStackSlot and
RISCVInstrInfo::loadRegFromStackSlot.

llvm-svn: 328104
2018-03-21 15:11:02 +00:00
Alex Bradbury 80c8eb7696 [RISCV] Add codegen for RV32F floating point load/store
As part of this, add support for load/store from the constant pool. This is
used to materialise f32 constants.

llvm-svn: 327979
2018-03-20 13:26:12 +00:00
Alex Bradbury 76c29ee815 [RISCV] Add codegen for RV32F arithmetic and conversion operations
Currently, only a soft floating point ABI is supported.

llvm-svn: 327976
2018-03-20 12:45:35 +00:00
Shiva Chen cbd498ac10 [RISCV] Preserve stack space for outgoing arguments when the function contain variable size objects
E.g.

bar (int x)
{
  char p[x];

  push outgoing variables for foo.
  call foo
}

We need to generate stack adjustment instructions for outgoing arguments by
eliminateCallFramePseudoInstr when the function contains variable size
objects to avoid outgoing variables corrupt the variable size object.

Default hasReservedCallFrame will return !hasFP().
We don't want to generate extra sp adjustment instructions when hasFP()
return true, So We override hasReservedCallFrame as !hasVarSizedObjects().

Differential Revision: https://reviews.llvm.org/D43752

llvm-svn: 327938
2018-03-20 01:39:17 +00:00
Alex Bradbury 0171a9f4ec [RISCV] Peephole optimisation for load/store of global values or constant 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
2018-03-19 11:54:28 +00:00
Sameer AbuAsal 2646a41e54 [RISCV] Implement MC relaxations for compressed instructions.
Summary:
     This patch implements relaxation for RISCV in the MC layer.
      The following relaxations are currently handled:
      1) Relax C_BEQZ to BEQ and C_BNEZ to BNEZ in RISCV.
      2) Relax and C_J $imm  to JAL x0, $imm  and CJAL to JAL ra, $imm.

Reviewers: asb, llvm-commits, efriedma

Reviewed By: asb

Subscribers: shiva0217

Differential Revision: https://reviews.llvm.org/D43055

llvm-svn: 326626
2018-03-02 22:04:12 +00:00
Geoff Berry f8bf2ec0a8 [MachineOperand][Target] MachineOperand::isRenamable semantics changes
Summary:
Add a target option AllowRegisterRenaming that is used to opt in to
post-register-allocation renaming of registers.  This is set to 0 by
default, which causes the hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq
fields of all opcodes to be set to 1, causing
MachineOperand::isRenamable to always return false.

Set the AllowRegisterRenaming flag to 1 for all in-tree targets that
have lit tests that were effected by enabling COPY forwarding in
MachineCopyPropagation (AArch64, AMDGPU, ARM, Hexagon, Mips, PowerPC,
RISCV, Sparc, SystemZ and X86).

Add some more comments describing the semantics of the
MachineOperand::isRenamable function and how it is set and maintained.

Change isRenamable to check the operand's opcode
hasExtraSrcRegAllocReq/hasExtraDstRegAllocReq bit directly instead of
relying on it being consistently reflected in the IsRenamable bit
setting.

Clear the IsRenamable bit when changing an operand's register value.

Remove target code that was clearing the IsRenamable bit when changing
registers/opcodes now that this is done conservatively by default.

Change setting of hasExtraSrcRegAllocReq in AMDGPU target to be done in
one place covering all opcodes that have constant pipe read limit
restrictions.

Reviewers: qcolombet, MatzeB

Subscribers: aemerson, arsenm, jyknight, mcrosier, sdardis, nhaehnle, javed.absar, tpr, arichardson, kristof.beyls, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, jordy.potman.lists, apazos, sabuasal, niosHD, escha, nemanjai, llvm-commits

Differential Revision: https://reviews.llvm.org/D43042

llvm-svn: 325931
2018-02-23 18:25:08 +00:00
Shiva Chen 7c17242b92 [RISCV] Implement c.lui immediate operand constraint
Implement c.lui immediate constraint to [1, 31] and [0xfffe0, 0xfffff].
The RISC-V ISA describes the constraint as [1, 63], with that value
being loaded in to bits 17-12 of the destination register and sign extended
from bit 17. Therefore, this 6-bit immediate can represent values in the
ranges [1, 31] and [0xfffe0, 0xfffff].

Differential Revision: https://reviews.llvm.org/D42834

llvm-svn: 325792
2018-02-22 15:02:28 +00:00
Alex Bradbury 8d8d0a733f [RISCV][NFC] Make logic in RISCVMCCodeEmitter::getImmOpValue more defensive
As pointed out by @sabuasal in a comment on D23568, the logic in  
RISCVMCCodeEmitter::getImmOpValue could be more defensive. Although with the  
current instruction definitions it is always the case that `VK_RISCV_LO` is  
always used with either an I- or S-format instruction, this may not always be  
the case in the future. Add a check to ensure we will get an assertion in  
debug builds if that changes.

llvm-svn: 325775
2018-02-22 13:24:25 +00:00
Ahmed Charles 646ab87bb4 [RISCV] Add support for %pcrel_lo.
llvm-svn: 324303
2018-02-06 00:55:23 +00:00
Shiva Chen b22c1d29bc [RISCV] Fix c.addi and c.addi16sp immediate constraints which should be non-zero
Differential Revision: https://reviews.llvm.org/D42782

llvm-svn: 324055
2018-02-02 02:43:23 +00:00
Shiva Chen bbf4c5c25e [RISCV] Define getSetCCResultType for setting vector setCC type
To avoid trigger "No default SetCC type for vectors!" Assertion

Differential Revision: https://reviews.llvm.org/D42675

llvm-svn: 324054
2018-02-02 02:43:18 +00:00
Craig Topper 8f324bb1a4 [SelectionDAGISel] Add a debug print before call to Select. Adjust where 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
2018-01-26 19:34:20 +00:00
Shiva Chen 056d835fa4 [RISCV] Encode RISCV specific ELF e_flags to RISCV Binary by RISCVTargetStreamer
llvm-svn: 323507
2018-01-26 07:53:07 +00:00
Ana Pazos 1b57c7a0f4 [RISCV] Fixed setting predicates for compressed instructions.
Summary:
Fixed setting predicates for compressed instructions.
Some instructions were being generated with C extension
enabled only, without proper checks for the other
required extensions like F, D and 32 and 64-bit target checks.
Affected instructions:
C_FLD, C_FLW, C_LD, C_FSD, C_FSW, C_SD,
C_JAL, C_ADDIW, C_SUBW, C_ADDW,
C_FLDSP, C_FLWSP, C_LDSP, C_FSDSP, C_FSWSP, C_SDSP

Reviewers: asb, shiva0217

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, sabuasal, niosHD, llvm-commits

Differential Revision: https://reviews.llvm.org/D42132

llvm-svn: 322876
2018-01-18 18:54:05 +00:00
Alex Bradbury 921383828e [RISCV] Codegen support for the standard RV32M instruction set extension
llvm-svn: 322843
2018-01-18 12:36:38 +00:00
Alex Bradbury 7d6aa1f7ae [RISCV] Implement frame pointer elimination
llvm-svn: 322839
2018-01-18 11:34:02 +00:00
Alex Bradbury d93f889d89 [RISCV] Allow RISCVAsmBackend::writeNopData to generate c.nop when supported
When the compressed instruction set is enabled, the 16-bit c.nop can be
generated if necessary.

Differential Revision: https://reviews.llvm.org/D41221
Patch by Shiva Chen.

llvm-svn: 322658
2018-01-17 14:17:12 +00:00
Ana Pazos e3d248361e [RISCV] Pass MCSubtargetInfo to print methods.
Summary:

This change allows checking for ISA extensions in print methods.

Reviewers: asb, niosHD

Reviewed By: asb, niosHD

Subscribers: llvm-commits, niosHD, asb, rbar, johnrusso, simoncook, jordy.potman.lists, sabuasal

Differential Revision: https://reviews.llvm.org/D41503

llvm-svn: 322345
2018-01-12 02:27:00 +00:00
Alex Bradbury 0715d35ed5 [RISCV] Reserve an emergency spill slot for the register scavenger when necessary
Although the register scavenger can often find a spare register, an emergency 
spill slot is needed to guarantee success. Reserve this slot in cases where 
the function is known to have a large stack (meaning the scavenger may be 
needed when forming stack addresses).

llvm-svn: 322269
2018-01-11 11:17:19 +00:00
Alex Bradbury 315cd3ace4 [RISCV] Implement support for the BranchRelaxation pass
Branch relaxation is needed to support branch displacements that overflow the
instruction's immediate field.

Differential Revision: https://reviews.llvm.org/D40830

llvm-svn: 322224
2018-01-10 21:05:07 +00:00
Alex Bradbury e027c93ac2 [RISCV] Implement branch analysis
This is a prerequisite for the branch relaxation pass, and allows a number of
optimisation passes (e.g. BranchFolding and MachineBlockPlacement) to work.

Differential Revision: https://reviews.llvm.org/D40808

llvm-svn: 322222
2018-01-10 20:47:00 +00:00
Alex Bradbury 70f137b6bf [RISCV] Add support for llvm.{frameaddress,returnaddress} intrinsics
llvm-svn: 322218
2018-01-10 20:12:00 +00:00
Alex Bradbury 9330e64485 [RISCV] Add basic support for inline asm constraints
llvm-svn: 322217
2018-01-10 20:05:09 +00:00
Alex Bradbury 9fea4881d0 [RISCV] Support stack frames and offsets up to 32-bits
Differential Revision: https://reviews.llvm.org/D40807

llvm-svn: 322216
2018-01-10 19:53:46 +00:00
Alex Bradbury c85be0de56 [RISCV] Support for varargs
Includes support for expanding va_copy. Also adds support for using 'aligned'
registers when necessary for vararg calls, and ensure the frame pointer always
points to the bottom of the vararg spill region. This is necessary to ensure
that the saved return address and stack pointer are always available at fixed
known offsets of the frame pointer.

Differential Revision: https://reviews.llvm.org/D40805

llvm-svn: 322215
2018-01-10 19:41:03 +00:00
Alex Bradbury b22f751fa7 Thread MCSubtargetInfo through Target::createMCAsmBackend
Currently it's not possible to access MCSubtargetInfo from a TgtMCAsmBackend. 
D20830 threaded an MCSubtargetInfo reference through 
MCAsmBackend::relaxInstruction, but this isn't the only function that would 
benefit from access. This patch removes the Triple and CPUString arguments 
from createMCAsmBackend and replaces them with MCSubtargetInfo.

This patch just changes the interface without making any intentional 
functional changes. Once in, several cleanups are possible:
* Get rid of the awkward MCSubtargetInfo handling in ARMAsmBackend
* Support 16-bit instructions when valid in MipsAsmBackend::writeNopData
* Get rid of the CPU string parsing in X86AsmBackend and just use a SubtargetFeature for HasNopl
* Emit 16-bit nops in RISCVAsmBackend::writeNopData if the compressed instruction set extension is enabled (see D41221)

This change initially exposed PR35686, which has since been resolved in r321026.

Differential Revision: https://reviews.llvm.org/D41349

llvm-svn: 321692
2018-01-03 08:53:05 +00:00
Alex Bradbury 8cb894b34b [RISCV] Add Defs Uses information for c.jal and c.addi4spn
Differential Revision: https://reviews.llvm.org/D41339
Patch by Shiva Chen.

llvm-svn: 321643
2018-01-02 12:09:29 +00:00
Alex Bradbury 3633d1205f [RISCV][NFC] Resolve unused variable warning in RISCVISelLowering
XLenVT in LowerFormalArguments is used only in an assert.

llvm-svn: 321642
2018-01-02 11:54:59 +00:00
Alex Bradbury 0ad4c265d7 [RISCV] Change shift amount operand of RVC shift instructions to uimmlog2xlennonzero
c.slli/c.srli/c.srai allow a 5-bit shift in RV32C and a 6-bit shift in RV64C.
This patch adds uimmlog2xlennonzero to reflect this constraint as well as
tests.

Differential Revision: https://reviews.llvm.org/D41216

Patch by Shiva Chen.

llvm-svn: 320799
2017-12-15 10:20:51 +00:00
Alex Bradbury 59136ffab1 [RISCV] Enable emission of alias instructions by default
This patch switches the default for -riscv-no-aliases to false
and updates all affected MC and CodeGen tests. As recommended in
D41071, MC tests use the canonical instructions and the CodeGen
tests use the aliases.

Additionally, for the f and d instructions with rounding mode,
the tests for the aliased versions are moved and tightened such
that they can actually detect if alias emission is enabled.
(see D40902 for context)

Differential Revision: https://reviews.llvm.org/D41225

Patch by Mario Werner.

llvm-svn: 320797
2017-12-15 09:47:01 +00:00
Alex Bradbury 845e5dce83 [RISCV] Define sfence.vma InstAliases to match the GNU RISC-V tools
Unfortunately these aren't defined explicitly in the privileged spec, but the
GNU assembler does accept `sfence.vma` and `sfence.vma rs` as well as the
usual `sfence.vma rs, rt`.

llvm-svn: 320575
2017-12-13 12:46:55 +00:00
Alex Bradbury fa7e4ec837 [RISCV] Implement floating point assembler pseudo instructions
Adds the assembler aliases for the floating point instructions
which can be mapped to a single canonical instruction. The missing
pseudo instructions (flw, fld, fsw, fsd) are marked as TODO. Other
things, like for example PCREL_LO, have to be implemented first.

This patch builds upon D40902.

Differential Revision: https://reviews.llvm.org/D41071

Patch by Mario Werner.

llvm-svn: 320569
2017-12-13 11:37:19 +00:00
Alex Bradbury 19c9314aea [RISCV][NFC] Update RISCVInstrInfoC.td to match usual instruction naming convention
When an instruction mnemonic contains a '.', we usually name the instruction
with a _ in that place. e.g. fadd.s -> FADD_S.

This patch updates RISCVInstrInfoC.td to do the same, e.g. c.nop -> C_NOP.

Also includes some minor formatting changes in RISCVInstrInfoC.td to better
align it with the formatting conventions in the rest of the backend.

llvm-svn: 320560
2017-12-13 09:57:25 +00:00
Alex Bradbury 581d6b081d [RISCV][NFC] Put isSImm6 and simm6 td definition in correct sorted position
We sort these helper functions and td definitions by bit width. simm6 was
previously out-of-order with respect to the others.

llvm-svn: 320559
2017-12-13 09:41:21 +00:00
Alex Bradbury 60714f98ba [RISCV] MC layer support for the remaining RVC instructions
Differential Revision: https://reviews.llvm.org/D40003

Patch by Shiva Chen.

llvm-svn: 320558
2017-12-13 09:32:55 +00:00
Alex Bradbury c01db1ce8f [RISCV][NFC] Formatting fix in RISCVInstrInfo.td
llvm-svn: 320491
2017-12-12 16:10:21 +00:00
Alex Bradbury 9ed84c8ae8 [RISCV] Implement assembler pseudo instructions for RV32I and RV64I
Adds the assembler pseudo instructions of RV32I and RV64I which can
be mapped to a single canonical instruction. The missing pseudo
instructions (e.g., call, tail, ...) are marked as TODO. Other
things, like for example PCREL_LO, have to be implemented first.

Currently, alias emission is disabled by default to keep the patch
minimal. Alias emission by default will be enabled in a subsequent
patch which also updates all affected tests. Note that this patch
should actually break the floating point MC tests. However, the
used FileCheck configuration is not tight enought to detect the
breakage.

Differential Revision: https://reviews.llvm.org/D40902

Patch by Mario Werner.

llvm-svn: 320487
2017-12-12 15:46:15 +00:00
Alex Bradbury 8bba6bfeef [RISCV] MC layer support for the instructions added in the privileged spec
Adds support for the instructions added in the RISC-V privileged ISA
(https://content.riscv.org/wp-content/uploads/2017/05/riscv-privileged-v1.10.pdf):
uret, sret, mret, wfi, and sfence.vma.

Note from the committer: I made very minor formatting changes prior to commit, 
which didn't seem worth creating another review round-trip for.

Differential Revision: https://reviews.llvm.org/D40383

Patch by David Craven.

llvm-svn: 320484
2017-12-12 15:17:45 +00:00
Alex Bradbury dc31c61b18 [RISCV] Add custom CC_RISCV calling convention and improved call support
The TableGen-based calling convention definitions are inflexible, while
writing a function to implement the calling convention is very
straight-forward, and allows difficult cases to be handled more easily. With
this patch adds support for:
* Passing large scalars according to the RV32I calling convention
* Byval arguments
* Passing values on the stack when the argument registers are exhausted

The custom CC_RISCV calling convention is also used for returns.

This patch also documents the ABI lowering that a language frontend is 
expected to perform. I would like to work to simplify these requirements over 
time, but this will require further discussion within the LLVM community.

We add PendingArgFlags CCState, as a companion to PendingLocs.

The PendingLocs vector is used by a number of backends to handle arguments 
that are split during legalisation. However CCValAssign doesn't keep track of 
the original argument alignment. Therefore, add a PendingArgFlags vector which 
can be used to keep track of the ISD::ArgFlagsTy for every value added to 
PendingLocs.

Differential Revision: https://reviews.llvm.org/D39898

llvm-svn: 320359
2017-12-11 12:49:02 +00:00
Alex Bradbury bfb00d4c1c [RISCV] Allow lowering of dynamic_stackalloc, stacksave, stackrestore
llvm-svn: 320358
2017-12-11 12:38:17 +00:00
Alex Bradbury b014e3de52 [RISCV] Implement prolog and epilog insertion
As frame pointer elimination isn't implemented until a later patch and we make 
extensive use of update_llc_test_checks.py, this changes touches a lot of the 
RISC-V tests.

Differential Revision: https://reviews.llvm.org/D39849

llvm-svn: 320357
2017-12-11 12:34:11 +00:00
Alex Bradbury 660bcceccf [RISCV] Support lowering FrameIndex
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
2017-12-11 11:53:54 +00:00
Alex Bradbury f8f4b90544 [RISCV] MC layer support for the jump/branch instructions of the RVC extension
Differential Revision: https://reviews.llvm.org/D40002
    
Patch by Shiva Chen.

llvm-svn: 320038
2017-12-07 13:19:57 +00:00
Alex Bradbury 9f6aec4b7a [RISCV] MC layer support for load/store instructions of the C (compressed) extension
Differential Revision: https://reviews.llvm.org/D40001
    
Patch by Shiva Chen.

llvm-svn: 320037
2017-12-07 12:50:32 +00:00
Alex Bradbury 87a54d6110 [RISCV][NFC] Use TargetRegisterClass::hasSubClassEq in storeRegToStackSlot/loadReadFromStackSlot
Simply checking for register class equality will break once additional 
register classes are added (as is done for the RVC instruction set extension).

llvm-svn: 320036
2017-12-07 12:45:05 +00:00
Alex Bradbury ee8950efd5 [RISCV] MC layer support for the standard RV64D instruction set extension
llvm-svn: 320029
2017-12-07 11:04:18 +00:00
Alex Bradbury 4dd94e0ccd [RISCV] MC layer support for the standard RV64F instruction set extension
llvm-svn: 320028
2017-12-07 11:02:55 +00:00
Alex Bradbury 48f95a655d [RISCV] MC layer support for the standard RV64A instruction set extension
llvm-svn: 320027
2017-12-07 10:59:12 +00:00
Alex Bradbury 81def7224e [RISCV] MC layer support for the standard RV64M instruction set extension
llvm-svn: 320026
2017-12-07 10:56:07 +00:00
Alex Bradbury a6e6248307 [RISCV] MC layer support for the standard RV64I instructions
llvm-svn: 320024
2017-12-07 10:53:48 +00:00
Alex Bradbury 7bc2a95bb9 [RISCV] MC layer support for the standard RV32D instruction set extension
As the FPR32 and FPR64 registers have the same names, use 
validateTargetOperandClass in RISCVAsmParser to coerce a parsed FPR32 to an 
FPR64 when necessary. The rest of this patch is very similar to the RV32F 
patch.

Differential Revision: https://reviews.llvm.org/D39895

llvm-svn: 320023
2017-12-07 10:46:23 +00:00
Alex Bradbury 0d6cf90663 [RISCV] MC layer support for the standard RV32F instruction set extension
The most interesting part of this patch is probably the handling of 
rounding mode arguments. Sadly, the RISC-V assembler handles floating point 
rounding modes as a special "argument" when it would be more consistent to 
handle them like the atomics, opcode suffixes. This patch supports parsing 
this optional parameter, using InstAlias to allow parsing these floating point 
instructions when no rounding mode is specified.

Differential Revision: https://reviews.llvm.org/D39893

llvm-svn: 320020
2017-12-07 10:26:05 +00:00
Alex Bradbury e2f664e1c6 [RISCV][NFC] Remove unnecessary {} around single statement if block
Almost too trivial to worry about, but it seems worth having consistency with
upcoming commits.

llvm-svn: 318760
2017-11-21 12:41:41 +00:00
Alex Bradbury 9caefe364a [RISCV][NFC] Clean up RISCVDAGToDAGISel::Select
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
2017-11-21 12:00:19 +00:00
Alex Bradbury 0c7b3643f7 [RISCV] Use register X0 (ZERO) for constant 0
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
2017-11-21 08:23:08 +00:00
Alex Bradbury ffc435e9c7 [RISCV] Support and tests for a variety of additional LLVM IR constructs
Previous patches primarily ensured that codegen was possible for the standard
RISC-V instructions. However, there are a number of IR inputs that wouldn't be
appropriately lowered. This patch both adds test cases and supports lowering
for a number of these cases:
* Improved sext/zext/trunc support
* Support for setcc variants that don't map directly to RISC-V instructions
* Lowering mul, and hence support for external symbols
* addc, adde, subc, sube
* mulhs, srem, mulhu, urem, udiv, sdiv
* {srl,sra,shl}_parts
* brind
* br_jt
* bswap, ctlz, cttz, ctpop
* rotl, rotr
* BlockAddress operands

Differential Revision: https://reviews.llvm.org/D29938

llvm-svn: 318737
2017-11-21 08:11:03 +00:00
Alex Bradbury 65385167fb [RISCV] Implement lowering of ISD::SELECT
Although ISD::SELECT_CC is a more natural match for RISCVISD::SELECT_CC (and
ultimately the integer RISC-V conditional branch instructions), we choose to
expand ISD::SELECT_CC and lower ISD::SELECT. The appropriate compare+branch
will be created in the case where an ISD::SELECT condition value is created by
an ISD::SETCC node, which operates on XLen types. Other datatypes such as
floating point don't have conditional branch instructions, and lowering
ISD::SELECT allows more flexibility for handling these cases.

Differential Revision: https://reviews.llvm.org/D29937

llvm-svn: 318735
2017-11-21 07:51:32 +00:00
David Blaikie b3bde2ea50 Fix a bunch more layering of CodeGen headers that are in Target
All these headers already depend on CodeGen headers so moving them into
CodeGen fixes the layering (since CodeGen depends on Target, not the
other way around).

llvm-svn: 318490
2017-11-17 01:07:10 +00:00
Mandeep Singh Grang 47fbc5911d [RISCV] Fix 64-bit data layout mismatch between backend and target description
Reviewers: asb

Reviewed By: asb

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, llvm-commits

Differential Revision: https://reviews.llvm.org/D40145

llvm-svn: 318454
2017-11-16 20:30:49 +00:00
Azharuddin Mohammed fa8420d0a1 Fix RISCV build after r318352
Reviewers: asb, apazos, mgrang

Reviewed By: mgrang

Subscribers: rbar, johnrusso, simoncook, jordy.potman.lists, llvm-commits

Differential Revision: https://reviews.llvm.org/D40139

llvm-svn: 318437
2017-11-16 18:39:31 +00:00
Mandeep Singh Grang 5f043ae2e1 [RISCV] Silence an unused variable warning in release builds [NFC]
Summary:
Also minor cleanups:
1. Avoided multiple calls to Fixup.getKind()
2. Avoided multiple calls to getFixupKindInfo()
3. Removed a redundant return.

Reviewers: asb, apazos

Reviewed By: asb

Subscribers: rbar, johnrusso, llvm-commits

Differential Revision: https://reviews.llvm.org/D39881

llvm-svn: 317908
2017-11-10 19:09:28 +00:00
Alex Bradbury 8c345c5aa9 [RISCV] MC layer support for the standard RV32A instruction set extension
llvm-svn: 317791
2017-11-09 15:00:03 +00:00
Alex Bradbury a47514ce3f [RISCV] MC layer support for the standard RV32M instruction set extension
llvm-svn: 317788
2017-11-09 14:46:30 +00:00
Alex Bradbury a337675cdb [RISCV] Initial support for function calls
Note that this is just enough for simple function call examples to generate 
working code. Support for varargs etc follows in future patches.

Differential Revision: https://reviews.llvm.org/D29936

llvm-svn: 317691
2017-11-08 13:41:21 +00:00
Alex Bradbury 74913e1c70 [RISCV] Codegen for conditional branches
A good portion of this patch is the extra functions that needed to be 
implemented to support the test case. e.g. storeRegToStackSlot, 
loadRegFromStackSlot, eliminateFrameIndex.

Setting ISD::BR_CC to Expand may appear non-obvious on an architecture with 
branch+cmp instructions. However, I found it much easier to deal with matching 
the expanded form.

I had to change simm13_lsb0 and simm21_lsb0 to inherit from the 
Operand<OtherVT> class rather than Operand<i32> in order to keep tablegen 
happy. This isn't a big deal, but it does seem a shame to lose the uniformity 
across immediate types when there's not an obvious benefit (I'm hoping a 
tablegen expert will educate me on what I'm missing here!).

Differential Revision: https://reviews.llvm.org/D29935

llvm-svn: 317690
2017-11-08 13:31:40 +00:00
Alex Bradbury ec8aa91305 [RISCV] Codegen support for memory operations on global addresses
Differential Revision: https://reviews.llvm.org/D39103

llvm-svn: 317688
2017-11-08 13:24:21 +00:00
Alex Bradbury cfa6291bb1 [RISCV] Codegen support for memory operations
This required the implementation of RISCVTargetInstrInfo::copyPhysReg. Support
for lowering global addresses follow in the next patch.

Differential Revision: https://reviews.llvm.org/D29934

llvm-svn: 317685
2017-11-08 12:20:01 +00:00
Alex Bradbury 0f0e1b54f0 [RISCV] Codegen support for materializing constants
Differential Revision: https://reviews.llvm.org/D39101

llvm-svn: 317684
2017-11-08 12:02:22 +00:00
Alex Bradbury cc988415fe [NFCI] Ensure TargetOpcode::* are compatible with guessInstructionProperties=0
rL162640 introduced CodeGenTarget::guessInstructionProperties. If a target 
sets guessInstructionProperties=0 in its FooInstrInfo, tablegen will error if 
it has to guess properties from patterns. Unfortunately, 
guessInstructionProperties=0 can't be used with current upstream LLVM as 
instructions in the TargetOpcode namespace are always included and sometimes 
have inferred properties for mayLoad, mayStore, and hasSideEffects. This patch 
provides the simplest possible fix to this problem, setting default values for 
these fields in the TargetOpcode scope. There is no intended functional 
change, as the explicitly set properties should match what was previously 
inferred. A number of the instructions had hasSideEffects=1 inferred 
unintentionally. This patch makes it explicit, while future patches (such as 
D37097) correct the property.

Differential Revision: https://reviews.llvm.org/D37065

llvm-svn: 317674
2017-11-08 09:26:06 +00:00
David Blaikie 3f833edc7c Target/TargetInstrInfo.h -> CodeGen/TargetInstrInfo.h to match layering
This header includes CodeGen headers, and is not, itself, included by
any Target headers, so move it into CodeGen to match the layering of its
implementation.

llvm-svn: 317647
2017-11-08 01:01:31 +00:00
David Blaikie 1be62f0327 Move TargetFrameLowering.h to CodeGen where it's implemented
This header already includes a CodeGen header and is implemented in
lib/CodeGen, so move the header there to match.

This fixes a link error with modular codegeneration builds - where a
header and its implementation are circularly dependent and so need to be
in the same library, not split between two like this.

llvm-svn: 317379
2017-11-03 22:32:11 +00:00
Alex Bradbury c6c4e8bd5a [RISCV] Add missing hunk from r316188
r316188 didn't set guessInstructionProperties=1 as it should have done.

llvm-svn: 316189
2017-10-19 21:43:29 +00:00
Alex Bradbury 8971842f43 [RISCV] Initial codegen support for ALU operations
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
2017-10-19 21:37:38 +00:00
Alex Bradbury 3c941e7ed9 [RISCV] RISCVAsmParser: early exit if RISCVOperand isn't immediate as expected
This is necessary to avoid an assertion in the included test case and similar 
assembler inputs.

llvm-svn: 316168
2017-10-19 16:22:51 +00:00
Alex Bradbury baa54d4ac8 [RISCV][NFC] Drop unused parameter from createImm helper in RISCVAsmParser
llvm-svn: 316167
2017-10-19 16:09:20 +00:00
Alex Bradbury ee7c7ecd03 [RISCV] Prepare for the use of variable-sized register classes
While parameterising by XLen, also take the opportunity to clean up the 
formatting of the RISCV .td files.

This commit unifies the in-tree code with my patchset at 
<https://github.com/lowrisc/riscv-llvm>.

llvm-svn: 316159
2017-10-19 14:29:03 +00:00
Alex Bradbury 13ce95b77f [RISCV] Bugfix createRISCVELFObjectWriter
r315275 set the IsLittleEndian parameter incorrectly. This patch corrects 
this, and adds a test to ensure such mistakes will be caught in the future.

llvm-svn: 316091
2017-10-18 16:11:31 +00:00
Matthias Braun bb8507e63c Revert "TargetMachine: Merge TargetMachine and LLVMTargetMachine"
Reverting to investigate layering effects of MCJIT not linking
libCodeGen but using TargetMachine::getNameWithPrefix() breaking the
lldb bots.

This reverts commit r315633.

llvm-svn: 315637
2017-10-12 22:57:28 +00:00
Matthias Braun 3a9c114b24 TargetMachine: Merge TargetMachine and LLVMTargetMachine
Merge LLVMTargetMachine into TargetMachine.

- There is no in-tree target anymore that just implements TargetMachine
  but not LLVMTargetMachine.
- It should still be possible to stub out all the various functions in
  case a target does not want to use lib/CodeGen
- This simplifies the code and avoids methods ending up in the wrong
  interface.

Differential Revision: https://reviews.llvm.org/D38489

llvm-svn: 315633
2017-10-12 22:28:54 +00:00
Alex Bradbury 5c1eef4618 [RISCV] Fix build after r315327
Differential Revision: https://reviews.llvm.org/D38779
Patch by Chih-Mao Chen.

llvm-svn: 315455
2017-10-11 12:09:06 +00:00
Oliver Stannard 4191b9eaea [Asm] Add debug tracing in table-generated assembly matcher
This adds debug tracing to the table-generated assembly instruction matcher,
enabled by the -debug-only=asm-matcher option.

The changes in the target AsmParsers are to add an MCInstrInfo reference under
a consistent name, so that we can use it from table-generated code. This was
already being used this way for targets that use deprecation warnings, but 5
targets did not have it, and Hexagon had it under a different name to the other
backends.

llvm-svn: 315445
2017-10-11 09:17:43 +00:00
Alex Bradbury 8cc99f1887 [RISCV] Fix build after r315254
createELFObjectWriter now takes a std::unique_ptr<MCELFObjectTargetWriter> 
rather than a MCELFObjectTargetWriter*.

llvm-svn: 315275
2017-10-10 07:19:18 +00:00
Alex Bradbury 9d3f12501a [RISCV] Add common fixups and relocations
%lo(), %hi(), and %pcrel_hi() are supported and test cases have been added to 
ensure the appropriate fixups and relocations are generated. I've added an 
instruction format field which is used in RISCVMCCodeEmitter to, for 
instance, tell whether it should emit a lo12_i fixup or a lo12_s fixup 
(RISC-V has two 12-bit immediate encodings depending on the instruction 
type).

Differential Revision: https://reviews.llvm.org/D23568

llvm-svn: 314389
2017-09-28 08:26:24 +00:00
Alex Bradbury 8ab4a9696a [RISCV] Add support for disassembly
This Disassembly support allows for 'round-trip' testing, and rv32i-valid.s
has been updated appropriately.

Differential Revision: https://reviews.llvm.org/D23567

llvm-svn: 313486
2017-09-17 14:36:28 +00:00
Alex Bradbury 6758ecb98c [RISCV] Add support for all RV32I instructions
This patch supports all RV32I instructions as described in the RISC-V manual.
A future patch will add support for pseudoinstructions and other instruction
expansions (e.g. 0-arg fence -> fence iorw, iorw).

Differential Revision: https://reviews.llvm.org/D23566

llvm-svn: 313485
2017-09-17 14:27:35 +00:00
Alex Bradbury 4f7f0da574 [RISCV][NFC] Fix sorting of includes in lib/Target/RISCV
llvm-svn: 312624
2017-09-06 09:21:21 +00:00
Alex Bradbury 21c8adf50b [RISCV] Trivial whitespace fix in RISCVInstPrinter
llvm-svn: 311277
2017-08-20 06:58:43 +00:00
Alex Bradbury e45186d43f [RISCV] Fix two abuses of llvm_unreachable
Replace with report_fatal_error.

llvm-svn: 311276
2017-08-20 06:57:27 +00:00
Alex Bradbury dd83484ab4 [RISCV] Set HasRelocationAddend for RISCVELFObjectWriter
llvm-svn: 311275
2017-08-20 06:55:14 +00:00
Alex Bradbury 2fee9ead7e [RISCV] Add RISCVInstPrinter and basic MC assembler tests
With the addition of RISCVInstPrinter, it is now possible to test the basic 
operation of the RISCV MC layer.

Differential Revision: https://reviews.llvm.org/D23564

llvm-svn: 310917
2017-08-15 13:08:29 +00:00
Alex Bradbury 6b34069ab7 [RISCV] Fix warning about unused getSubtargetFeatureName()
llvm-svn: 310375
2017-08-08 16:20:39 +00:00
Alex Bradbury 04f06d922f [RISCV] Add basic RISCVAsmParser (missing files)
This commit adds the files missing from rL310361. Apologies for the noise.

Differential Revision: https://reviews.llvm.org/D23563

llvm-svn: 310363
2017-08-08 14:43:36 +00:00
Alex Bradbury 1a4272914d [RISCV] Add basic RISCVAsmParser
This doesn't yet support parsing things like %pcrel_hi(foo), but will handle
basic instructions with register or immediate operands.

Differential Revision: https://reviews.llvm.org/D23563

llvm-svn: 310361
2017-08-08 14:32:35 +00:00
Rafael Espindola 79e238afee Delete Default and JITDefault code models
IMHO it is an antipattern to have a enum value that is Default.

At any given piece of code it is not clear if we have to handle
Default or if has already been mapped to a concrete value. In this
case in particular, only the target can do the mapping and it is nice
to make sure it is always done.

This deletes the two default enum values of CodeModel and uses an
explicit Optional<CodeModel> when it is possible that it is
unspecified.

llvm-svn: 309911
2017-08-03 02:16:21 +00:00
Rafael Espindola 1beb702ba2 Fully fix the movw/movt addend.
The issue is not if the value is pcrel. It is whether we have a
relocation or not.

If we have a relocation, the static linker will select the upper
bits. If we don't have a relocation, we have to do it.

llvm-svn: 307730
2017-07-11 23:18:25 +00:00
Rafael Espindola f351292141 Remove redundant argument.
llvm-svn: 306189
2017-06-24 00:26:57 +00:00
Rafael Espindola 801b42de31 ARM: move some logic from processFixupValue to applyFixup.
processFixupValue is called on every relaxation iteration. applyFixup
is only called once at the very end. applyFixup is then the correct
place to do last minute changes and value checks.

While here, do proper range checks again for fixup_arm_thumb_bl. We
used to do it, but dropped because of thumb2. We now do it again, but
use the thumb2 range.

llvm-svn: 306177
2017-06-23 22:52:36 +00:00
Rafael Espindola 88d9e37ec8 Use a MutableArrayRef. NFC.
llvm-svn: 305968
2017-06-21 23:06:53 +00:00
Chandler Carruth 6bda14b313 Sort the remaining #include lines in include/... and lib/....
I did this a long time ago with a janky python script, but now
clang-format has built-in support for this. I fed clang-format every
line with a #include and let it re-sort things according to the precise
LLVM rules for include ordering baked into clang-format these days.

I've reverted a number of files where the results of sorting includes
isn't healthy. Either places where we have legacy code relying on
particular include ordering (where possible, I'll fix these separately)
or where we have particular formatting around #include lines that
I didn't want to disturb in this patch.

This patch is *entirely* mechanical. If you get merge conflicts or
anything, just ignore the changes in this patch and run clang-format
over your #include lines in the files.

Sorry for any noise here, but it is important to keep these things
stable. I was seeing an increasing number of patches with irrelevant
re-ordering of #include lines because clang-format was used. This patch
at least isolates that churn, makes it easy to skip when resolving
conflicts, and gets us to a clean baseline (again).

llvm-svn: 304787
2017-06-06 11:49:48 +00:00
Matthias Braun 5e394c3d6f TargetPassConfig: Keep a reference to an LLVMTargetMachine; NFC
TargetPassConfig is not useful for targets that do not use the CodeGen
library, so we may just as well store a pointer to an
LLVMTargetMachine instead of just to a TargetMachine.

While at it, also change the constructor to take a reference instead of a
pointer as the TM must not be nullptr.

llvm-svn: 304247
2017-05-30 21:36:41 +00:00
Konstantin Zhuravlyov dc77b2e960 Distinguish between code pointer size and DataLayout::getPointerSize() in DWARF info generation
llvm-svn: 300463
2017-04-17 17:41:25 +00:00
Alex Bradbury 866113c2ea Add MCContext argument to MCAsmBackend::applyFixup for error reporting
A number of backends (AArch64, MIPS, ARM) have been using
MCContext::reportError to report issues such as out-of-range fixup values in
their TgtAsmBackend. This is great, but because MCContext couldn't easily be
threaded through to the adjustFixupValue helper function from its usual
callsite (applyFixup), these backends ended up adding an MCContext* argument
and adding another call to applyFixup to processFixupValue. Adding an
MCContext parameter to applyFixup makes this unnecessary, and even better -
applyFixup can take a reference to MCContext rather than a potentially null
pointer.

Differential Revision: https://reviews.llvm.org/D30264

llvm-svn: 299529
2017-04-05 10:16:14 +00:00
Alex Bradbury e4f731b813 [RISCV] Fix RV32 datalayout string and ensure initAsmInfo is called
llvm-svn: 295028
2017-02-14 05:20:20 +00:00
Alex Bradbury 6be16fbfb8 [RISCV] Pseudo instructions are isCodeGenOnly, have blank asmstr
llvm-svn: 295027
2017-02-14 05:17:23 +00:00
Alex Bradbury d36e04cb6c [RISCV] Fix unused variable in RISCVMCTargetDesc. NFC
Also, for better uniformity use TargetRegistry::RegisterMCAsmInfo rather than 
RegisterMCAsmInfoFn. Again, no functional change.

llvm-svn: 295026
2017-02-14 05:15:24 +00:00
Aaron Ballman 3ac3a7efff Removing a switch statement that contains a default label, but no case labels. Silences an MSVC warning; NFC.
llvm-svn: 285806
2016-11-02 13:58:57 +00:00
Alex Bradbury 6b2cca7f8f [RISCV] Add bare-bones RISC-V MCTargetDesc
This is enough to compile and link but doesn't yet do anything particularly 
useful. Once an ASM parser and printer are added in the next two patches, the 
whole thing can be usefully tested.

Differential Revision: https://reviews.llvm.org/D23562

llvm-svn: 285770
2016-11-01 23:47:30 +00:00
Alex Bradbury 24d9b13b36 [RISCV 4/10] Add basic RISCV{InstrFormats,InstrInfo,RegisterInfo,}.td
For now, only add instruction definitions for basic ALU operations. Our 
initial target is a working MC layer rather than codegen, so appropriate 
SelectionDAG patterns will come later.

Differential Revision: https://reviews.llvm.org/D23561

llvm-svn: 285769
2016-11-01 23:40:28 +00:00