[RISCV][GISel] Remove unneeded code from RISCVCallLowering::canLowerReturn. NFC

[topperc]

This code calculates FirstMaskArgument which used to be an argument to RISCV_CC, but was removed over a year ago.

[llvmbot]

@llvm/pr-subscribers-backend-risc-v

Author: Craig Topper (topperc)

Changes

This code calculates FirstMaskArgument which used to be an argument to RISCV_CC, but was removed over a year ago.

---

Full diff: https://github.com/llvm/llvm-project/pull/162144.diff

1 Files Affected:

• (modified) llvm/lib/Target/RISCV/GISel/RISCVCallLowering.cpp (-12)

diff --git a/llvm/lib/Target/RISCV/GISel/RISCVCallLowering.cpp b/llvm/lib/Target/RISCV/GISel/RISCVCallLowering.cpp
index 34026ed5d47a4..ecfb5febaae74 100644
--- a/llvm/lib/Target/RISCV/GISel/RISCVCallLowering.cpp
+++ b/llvm/lib/Target/RISCV/GISel/RISCVCallLowering.cpp
@@ -439,18 +439,6 @@ bool RISCVCallLowering::canLowerReturn(MachineFunction &MF,
   CCState CCInfo(CallConv, IsVarArg, MF, ArgLocs,
                  MF.getFunction().getContext());
 
-  const RISCVSubtarget &Subtarget = MF.getSubtarget<RISCVSubtarget>();
-
-  std::optional<unsigned> FirstMaskArgument = std::nullopt;
-  // Preassign the first mask argument.
-  if (Subtarget.hasVInstructions()) {
-    for (const auto &ArgIdx : enumerate(Outs)) {
-      MVT ArgVT = MVT::getVT(ArgIdx.value().Ty);
-      if (ArgVT.isVector() && ArgVT.getVectorElementType() == MVT::i1)
-        FirstMaskArgument = ArgIdx.index();
-    }
-  }
-
   for (unsigned I = 0, E = Outs.size(); I < E; ++I) {
     MVT VT = MVT::getVT(Outs[I].Ty);
     if (CC_RISCV(I, VT, VT, CCValAssign::Full, Outs[I].Flags[0], CCInfo,

[lenary]

LGTM