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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@322215 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320359 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318737 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@318735 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@317690 91177308-0d34-0410-b5e6-96231b3b80d8
Shiva Chen