Commit Graph

12 Commits

Author SHA1 Message Date
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
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 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
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 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 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 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 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 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 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