From 68b20c589c4890c28fbabe6e2f4636f41d47fd0b Mon Sep 17 00:00:00 2001
From: Diana Picus <diana.picus@linaro.org>
Date: Mon, 27 May 2019 10:30:33 +0000
Subject: [PATCH] [ARM GlobalISel] Cleanup CallLowering a bit

We never actually use the Offsets produced by ComputeValueVTs, so remove
them until we need them.

llvm-svn: 361755
---
 llvm/lib/Target/ARM/ARMCallLowering.cpp | 33 ++++++++++++---------------------
 llvm/lib/Target/ARM/ARMCallLowering.h   |  2 +-
 2 files changed, 13 insertions(+), 22 deletions(-)

diff --git a/llvm/lib/Target/ARM/ARMCallLowering.cpp b/llvm/lib/Target/ARM/ARMCallLowering.cpp
index 5229064..bfdf7f0 100644
--- a/llvm/lib/Target/ARM/ARMCallLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMCallLowering.cpp
@@ -192,8 +192,7 @@ void ARMCallLowering::splitToValueTypes(
   const Function &F = MF.getFunction();
 
   SmallVector<EVT, 4> SplitVTs;
-  SmallVector<uint64_t, 4> Offsets;
-  ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitVTs, &Offsets, 0);
+  ComputeValueVTs(TLI, DL, OrigArg.Ty, SplitVTs, nullptr, nullptr, 0);
 
   if (SplitVTs.size() == 1) {
     // Even if there is no splitting to do, we still want to replace the
@@ -206,7 +205,6 @@ void ARMCallLowering::splitToValueTypes(
     return;
   }
 
-  unsigned FirstRegIdx = SplitArgs.size();
   for (unsigned i = 0, e = SplitVTs.size(); i != e; ++i) {
     EVT SplitVT = SplitVTs[i];
     Type *SplitTy = SplitVT.getTypeForEVT(Ctx);
@@ -224,13 +222,11 @@ void ARMCallLowering::splitToValueTypes(
         Flags.setInConsecutiveRegsLast();
     }
 
-    SplitArgs.push_back(
-        ArgInfo{MRI.createGenericVirtualRegister(getLLTForType(*SplitTy, DL)),
-                SplitTy, Flags, OrigArg.IsFixed});
+    unsigned PartReg =
+        MRI.createGenericVirtualRegister(getLLTForType(*SplitTy, DL));
+    SplitArgs.push_back(ArgInfo{PartReg, SplitTy, Flags, OrigArg.IsFixed});
+    PerformArgSplit(PartReg);
   }
-
-  for (unsigned i = 0; i < Offsets.size(); ++i)
-    PerformArgSplit(SplitArgs[FirstRegIdx + i].Reg, Offsets[i] * 8);
 }
 
 /// Lower the return value for the already existing \p Ret. This assumes that
@@ -262,9 +258,8 @@ bool ARMCallLowering::lowerReturnVal(MachineIRBuilder &MIRBuilder,
     setArgFlags(CurArgInfo, AttributeList::ReturnIndex, DL, F);
 
     SmallVector<unsigned, 4> Regs;
-    splitToValueTypes(
-        CurArgInfo, SplitVTs, MF,
-        [&](unsigned Reg, uint64_t Offset) { Regs.push_back(Reg); });
+    splitToValueTypes(CurArgInfo, SplitVTs, MF,
+                      [&](unsigned Reg) { Regs.push_back(Reg); });
     if (Regs.size() > 1)
       MIRBuilder.buildUnmerge(Regs, VRegs[i]);
   }
@@ -466,9 +461,8 @@ bool ARMCallLowering::lowerFormalArguments(MachineIRBuilder &MIRBuilder,
 
     SplitRegs.clear();
 
-    splitToValueTypes(AInfo, ArgInfos, MF, [&](unsigned Reg, uint64_t Offset) {
-      SplitRegs.push_back(Reg);
-    });
+    splitToValueTypes(AInfo, ArgInfos, MF,
+                      [&](unsigned Reg) { SplitRegs.push_back(Reg); });
 
     if (!SplitRegs.empty())
       MIRBuilder.buildMerge(VRegs[Idx], SplitRegs);
@@ -575,9 +569,8 @@ bool ARMCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
       return false;
 
     SmallVector<unsigned, 8> Regs;
-    splitToValueTypes(Arg, ArgInfos, MF, [&](unsigned Reg, uint64_t Offset) {
-      Regs.push_back(Reg);
-    });
+    splitToValueTypes(Arg, ArgInfos, MF,
+                      [&](unsigned Reg) { Regs.push_back(Reg); });
 
     if (Regs.size() > 1)
       MIRBuilder.buildUnmerge(Regs, Arg.Reg);
@@ -598,9 +591,7 @@ bool ARMCallLowering::lowerCall(MachineIRBuilder &MIRBuilder,
     ArgInfos.clear();
     SmallVector<unsigned, 8> SplitRegs;
     splitToValueTypes(OrigRet, ArgInfos, MF,
-                      [&](unsigned Reg, uint64_t Offset) {
-                        SplitRegs.push_back(Reg);
-                      });
+                      [&](unsigned Reg) { SplitRegs.push_back(Reg); });
 
     auto RetAssignFn = TLI.CCAssignFnForReturn(CallConv, IsVarArg);
     CallReturnHandler RetHandler(MIRBuilder, MRI, MIB, RetAssignFn);
diff --git a/llvm/lib/Target/ARM/ARMCallLowering.h b/llvm/lib/Target/ARM/ARMCallLowering.h
index d395a42..63760ef 100644
--- a/llvm/lib/Target/ARM/ARMCallLowering.h
+++ b/llvm/lib/Target/ARM/ARMCallLowering.h
@@ -47,7 +47,7 @@ private:
                       ArrayRef<unsigned> VRegs,
                       MachineInstrBuilder &Ret) const;
 
-  using SplitArgTy = std::function<void(unsigned Reg, uint64_t Offset)>;
+  using SplitArgTy = std::function<void(unsigned Reg)>;
 
   /// Split an argument into one or more arguments that the CC lowering can cope
   /// with (e.g. replace pointers with integers).
-- 
2.7.4